March 20, 2025

Security Software WG Deep-Dive: Robin Randhawa

Timeline of Events (or the story thus far)

• This is the first Security SW WG Deep Dive to the RISE TSC

• This is a relatively new Working Group

  • Justification for the WG first pitched to the RISE TSC in June 2024

  • Generally unanimous support

  • Working Group created in August 2024

  • First WG Kick-off meeting in September 2024

  • Monthly meets since then

• The story arc that has evolved since the WG’s inception

  • Initially: “Security is broad: What is it that we want to do ?”

  • Then: “Let’s look at all the security specific RVIA specs that are frozen/ratified”

  • Then: “Let’s focus on security for embedded first! No! Datacenter/enterprise first!”

  • Then: “Let’s find a common feature subset between embedded and the rest”

  • Then: “Let’s focus on embedded first but choose work that enables the rest too”

  • Finally: “Here’s a break-down of the work we need to do first, let’s talk”

Current Status: OP-TEE for RISC-V Work Definition in Progress

Next Steps

• Complete OP-TEE/OpenSBI work definitions

  • Get reviews done by key stakeholders (Firmware/SecSW WGs)

  • Post review - translate to RISE WG work packages

  • Nominate work package owners

  • Produce RFPs for suitable work to rope in contractors

• Bring in focus beyond embedded

  • Undergo a similar consensus driven work identification exercise

    • Areas

      • CoVE enablement

        • Qemu, OpenSBI, CoVE RDSM

  • Build work package definitions, get them reviewed

  • Nominate owners, produce RFPs

What has worked well

• Good, gradual convergence of opinions towards common goals

• Good cross WG collaboration!

  • Credits

    • Anup Patel (VentanaMicro)

    • Sunil VL (VentanaMicro)

    • Tim Ouyang (AndesTech)

    • Alvin Chang (AndesTech)

    • Ravi Sahita (Rivos)

    • Peter Lin (SiFive)

What has not worked well

• Everyone is busy!

  • Hard to get timely responses generally speaking

  • Need to constantly push and prod folks…

• More mailing list interactions needed

  • General tendency to leave discussions until WG monthly meets

  • Will try hard to change this!

• More enthusiasm needed!

  • Not enough folks attending monthly WG meets

  • Security is a generally dry topic, yes, but it is super important!!!

Mar 13, 2025

RISE Developer Infrastructure Deep Dive- Paul Walmsley

Topics

• Developer Infrastructure WG Introduction & Vision

• Build Farm

  • Introduction

  • Value

  • 2024Q4 Review

  • 2025Q1 Review

• Board Farm

• Developer Tools

• Looking Forward to 2025Q2

• Credits

Developer Infrastructure WG Introduction

• Charter

  • The Developer Infrastructure WG focuses on software and services to support open-source RISC-V developers - both RISE members and the broader open-source community.

• Co-chairs

  • Barna Ibrahim (Rivos)

  • Paul Walmsley (SiFive)

• TSC Chair Contact

  • Nathan Egge (Google)

Developer Infrastructure WG Vision

• Three mutually-supporting projects

  • RISE Build Farm (Active)

  • RISE Board Farm (Inactive)

  • RISE Developer Tooling (Active)

• Goal

  • Provide robust development infrastructure and tools to RISC-V developers

RISE Build Farm: Introduction

• Objective

  • Cross-build and test (in simulation) RISC-V ports of key open source software

• Running in Hetzner Cloud (new!)

• Björn Töpel (Rivos) coordinating

• Brian “Redbeard” Harrington (Red Hat): co-admin

• Status

  • Eight active projects 

    • ~22 active large VM instances on Hetzner Cloud

    • Mostly acting as Github Runner performing cross-compilation/qemu-system-riscv{32,64} tests

Build Farm: Value

• Thousands of builds, and millions of tests per month on key, foundational RISC-V open source projects

  • GCC, LLVM, Linux kernel, GLIBC, Python

• > 150 toolchain bugs found via our fuzzer instances

• Jeff Law/Ventana (and upstream GCC maintainer)

  • “We don’t commit anything into gcc for RISC-V that hasn’t passed the RISE gcc CI.  Incredibly helpful!” 

Build Farm: 2024Q4 Review 

• Eight existing projects running

  • RISE GCC pre-commit CI (Patrick O'Neill, Edwin Lu)

  • RISE GCC post-commit CI (Patrick O'Neill, Edwin Lu)

  • RISE GCC fuzzer CI (Patrick O'Neill, Edwin Lu)

  • RISE GCC microcontroller CI (Patrick O'Neill, Edwin Lu)

  • RISE GLIBC pre-commit CI (Patrick O'Neill, Edwin Lu)

  • RISE LLVM fuzzer CI (Patrick O'Neill, Edwin Lu)

  • RISE Linux Kernel CI (Björn Töpel)

  • RISE Python Wheels (Mark Ryan)

• Two existing projects temporarily expanded

  • RISE GCC fuzzer CI (Patrick O'Neill, Edwin Lu)

  • RISE LLVM fuzzer CI (Patrick O'Neill, Edwin Lu)

  • Remaining GCP credits leveraged to greatly expand the number of fuzzer instances running (and thus the number of bugs we could find)

    • Thanks to Patrick, Edwin, and Björn for putting in extra work to make this possible!

• One existing project shut down

  • RISE QEMU Aarch64 test system (Paul Walmsley, Max Chou)

    • No longer needed by RP005

• Considerable volunteer time spent preparing for the Hetzner transition and monitoring LF/Hetzner progress

• Google Cloud account closed out with ~$10,000 USD of credits unused (preserved as a safety margin)

  • All credits expired December 31, 2024

    • Thanks again to Google for the donation

• Hetzner account was not set up in time to complete the server transition before the end of the year

  • RISE incurred some direct budget costs in 2025Q1

    • Discussed in following slides

• Ran on GCP throughout January as we waited for the Hetzner account to be set up

  • Toolchain fuzzer instances temporarily shut down to reduce costs (non-critical services)

  • Required direct payment from RISE budget, as GCP credits expired EOY 2024

• Migrated to new Hetzner infrastructure at the end of January

  • Fast execution saved RISE money

  • Credits

    • Björn Töpel (Rivos), Patrick O’Neill (Rivos), Edwin Lu (Rivos), Mark Ryan (Rivos)

    • Brian “Redbeard” Harrington (Red Hat)

• Some challenges with the Google Cloud->Hetzner transition

  • Hetzner account not available for our use until end of January

    • Two month latency from when we requested it

  • Unplanned 30 hour outage at the end of February

    • Caused by a billing dispute

    • Adding external monitoring to catch outages sooner

  • Hetzner account migration at the beginning of March

    • Original Hetzner account not set up to bill in Euros

    • New account had to be created and instances migrated

• No ability for RISE to directly track expenditures on Hetzner

  • Our accounts do not have these permissions

  • Going forward, these deep dives will not include budget reports

• Two existing projects temporarily paused in January

  • RISE GCC fuzzer CI (Patrick O'Neill, Edwin Lu)

  • RISE LLVM fuzzer CI (Patrick O'Neill, Edwin Lu)

• One existing project expanded (as planned)

  • RISE Linux Kernel CI (Björn Töpel)

    • Doubled the number of servers to provide additional test coverage

RISE Board Farm

• Objective

  • Provide a range of Linux-capable RISC-V boards to run functionality and performance tests on CI-generated code

  • Investigate feasibility of providing developer access to boards

• Status

  • No significant progress in 2024Q4 or 2025Q1

    • Build Farm relocation and emergency response taking up all available management bandwidth

  • Planning to ramp up in 2025Q2

  • Volunteers solicited!

RISE Developer Tools

• Objective

  • Provide a full Linux system image build, boot, and development environment for use on both simulators (QEMU) and RISC-V hardware

    • Ideally combines cross and native development environment and native system software and userspace

• Status

  • Nathan’s Gentoo build available for general use with cutting-edge software included

    • Luca Barbedo putting in a lot of effort here

  • How to productize/test?

Credits

• Barna Ibrahim (Rivos): Co-chair

• Björn Töpel (Rivos): Kernel CI Build Farm Project Admin, Build Farm Lead

• Brian ‘redbeard’ Harrington (Redhat): Build Farm Administrator

• Edwin Lu (Rivos): Toolchain Build Farm Project Admin

• Mark Ryan (Rivos): Python Build Farm Project Admin

• Nathan Egge (Google): TSC contact, Developer Tools Lead

• Patrick O’Neill (Rivos): Toolchain Build Farm Project Admin

• Paul Walmsley (SiFive): Co-chair

Mar 6, 2025

Deep Dive Language Runtimes - Ludovic HENRY

• Status Update: Java

  • Support for Vector extension: continual work

    • Support for FP16, more compiler optimizations

  • Matching RVA23:

    • Added: Zicond, Zfa, Zvkt, Zvbb

    • Only missing: Zimop, Zcmop, Zcb, and Zawrs

• Status Update: Go

  • Matching RVA23:

    • It’s a work-in-progress

    • Adding C, V, B, Zicond, Zfa, Zihintpause, Zihintntl, Zcb, Zvbb, Zawrs

  • RP001

    • Wiki is up-to-date to track work to be done

• Status Update: Python

  • RP011: Python Package Support for RISC-V

    • Signed, work is ongoing

    • Official documentation: https://riseproject.gitlab.io/python/wheel_builder/

• Status Update: Python

  • Upstream projects can distribute on RISC-V:

    • No clear date for AlmaLinux availability on RISC-V

    • RockyLinux should be available in May 2025 on RISC-V

      • Viable alternative to AlmaLinux

• Work Prioritization

  • Wiki is up-to-date

    • Java: https://wiki.riseproject.dev/display/HOME/LR_00%3A+Java

    • Python: https://wiki.riseproject.dev/display/HOME/LR_01%3A+Python

    • Go: https://wiki.riseproject.dev/display/HOME/LR_02%3A+Go

    • Javascript: https://wiki.riseproject.dev/display/HOME/LR_06%3A+Javascript

    • Rust: https://wiki.riseproject.dev/display/HOME/LR_07%3A+Rust

    • WASM: https://wiki.riseproject.dev/display/HOME/LR_08%3A+WebAssembly

• Please comment on mailing list for prioritization

  • Anything not listed you’d like to see?

  • Anything not as high on the priority list as you expected?

Deep Dive Compilers/Toolchains – Jeff Law

• Apologies for last week, customer meeting I couldn’t miss

• RP007

  • Hoping to see upstream engagement on what they’re finding/fixing 

• RP008

  • making great progress on finding real issues and either fixing them or getting them recorded for future work

• Not sure if anyone has put their name in the hopper for leading the group.  I expect my bandwidth to be limited going forward, though could probably help cover GCC if absolutely necessary

• GCC– GCC 15 release cycle in progress, ETA May 1

  • Still fixing bugs, but nothing RISC-V specific that is particularly worrisome

  • Many optimizations across scalar and vector domains

    • CRC work was finally integrated

    • Cactu optimization work

    • Vector, emphasis on x264 perf and zvl128..zvl512

    • Function multi-versioning

    • Stack-clash mitigation

• Items for 2025

  • Xz vectorization.  POC shows ~12% on spec. 

  • Another round of Zbs & extension removal improvements, 

  • Fusion work (significant fixes, new cases, discovery)

  • Uarch support for vector costing/tuning

• LLVM – LLVM 20 release imminent

  • No major RISC-V specific concerns for release according to Philip & Craig

  • Stack clash mitigations have been integrated

  • Function Multi-versioning

  • Vectorize xz search loop

• Items for 1H2025

  • Folding “addi” into loads/stores more aggressively (done)

  • Shrink wrapping development done, just working through review comments

  • Landing pads for CFI (in flight)

  • Improvements for x264 vectorization, more work to be done

Feb 20, 2025

Deep Dive Simulator Emulator- Daniel Barboza

• SE_02_004 (RP005) - QEMU RVV performance enhancements

  • Development completed, reviews ongoing in the ML. Performance enhancement up to 500% depending on vector configuration and workload

  • Link to last report 

• SE_01_021 - QEMU RVA23 profile support

  • Queued in the maintainer’s tree

  • Prerequisite of other items such as “RISC-V Server SoC Reference Board”

• E-trace items (SE_01_024, SE_01_025, SE_01_026, SE_01_027)

  • New in 2025. Implementation of RISC-V Efficient Trace spec. Owner: Daniel Barboza (Ventana Micro)

  • Development ongoing

• Other items under review in the QEMU mailing list:

  • SE_01_003 - QEMU WorldGuard support

  • SE_01_004 - QEMU IOPMP support

• SE_01_022 - RISC-V Server SoC Reference Board

• SE_01_005 - QEMU PCIe passthru on x86 hosts

• SE_01_023 - QEMU RISC-V IOMMU Enhancements

• Not yet sent for review

  • SE_01_022 - QEMU P Extension support

• Items completed

  • SE_01_017 - QEMU ACPI SPCR Support for RISC-Vc

Feb 6, 2025

Kernel and Virtualization Deepdive- Anup Patel

What’s merged for Linux-6.14 ?

• Linux-6.14-rc1 was released on 2nd February 2025

• Noteworthy stuff merged for Linux-6.14:

  • Linux RISC-V

    • T-Head vector extensions support

  • KVM RISC-V

    • Svvptc, Zabha, and Ziccrse extension support for Guest/VM

    • Virtualize SBI system suspend extension for Guest/VM

    • Trap related exit statistics as SBI PMU firmware counters for Guest/VM

RVA23 profile: Discovery updates

• HWPROBE additions in Linux-6.14

  • No updates

• KVM ONE_REG additions in Linux-6.14

  • Zabha, Svvptc, and Ziccrse

• Kernel HWPROBE (27-01-2024, wiki)

  • TBD - 7 (7.45%), NA - 47 (50%), COMPLETED - 40 (42.55%), TOTAL - 94

• KVM ONE_REG (27-01-2024, wiki)

  • TBD - 24 (25.53%), NA - 13 (13.83%), COMPLETED - 57 (60.64%), TOTAL - 94

2024-1H: Project updates

• 2024-1H: Recently upstreamed projects

  • LK_03_023 - QEMU-KVM Zawrs support

  • LK_02_025 - KVM System Suspend Virtualization

  • LK_03_008 - QEMU-KVM AIA user-space irqchip_split support

• 2024-1H: Development status (27-01-2025, wiki)

  • TBD - 2 (4.08%), ONGOING - 1 (2.04%), COMPLETED - 46 (93.88%), TOTAL - 49

• 2024-1H: Upstreaming status (27-01-2025, wiki)

  • TBD - 3 (6.12%), ONGOING - 5 (10.21%), COMPLETED - 41 (83.67%), TOTAL - 49

2024-2H: Project updates

• 2024-2H: Recently development complete projects

  • LK_01_024 - Supervisor Counter delegation (Smcdeleg and Ssccfg) based perf

  • LK_01_025 - Control Transfer Record (Smctr and Ssctr) support in perf driver

  • LK_01_044 - Firmware Feature support

  • LK_01_045 - Message Proxy support

  • LK_01_046 - RPMI Clock driver using SBI MPXY

  • LK_02_028 - KVM Firmware Feature virtualization

  • LK_03_026 - KVMTOOL Svadu support

  • LK_03_034 - KVMTOOL Smnpm and Ssnpm support

• 2024-2H: Recently upstreamed projects

  • LK_02_027 - KVM Svvptc virtualization

• 2024-2H: Development status (27-01-2025, wiki)

  • TBD - 13 (35.14%), ONGOING - 1 (2.70%), COMPLETED - 23 (62.16%), TOTAL - 37

• 2024-2H: Upstreaming status (27-01-2025, wiki)

  • TBD - 18 (48.64%), ONGOING - 13 (35.14%), COMPLETED - 6 (16.22%), TOTAL - 37

Jan 30, 2025

Distro and Integration-  Brian Harrington

The most recent discussion revolved around the development of a unified database for RISC-V processors and related tools, aiming to streamline information access and collaboration within the community. Additionally we discussed some needs/desired with regards to automated builders (specifically hosted by GitHub/GitLab). Here's a structured summary of the key points:

1. RISC-V Unified Database:

• Hosted on GitHub at https://github.com/riscv-software-src/riscv-unified-db

• Purpose: To compile comprehensive details about RISC-V processors, platforms, and associated tools, facilitating easier access for developers.

2. Related Items:

• Reminder of https://riscv.builders , building / compiling software for RISC-V, though called out that it’s still insufficient for the u-boot development desired by members.

• Nathan Egge provided a PDF about LLVM-Mingw, detailing its use for cross-compiling RISC-V applications on Windows, which is crucial for developers in Windows environments.

Jan 23, 2025

System Libraries Deep Dive- Nathan Egge

Multimedia (and other) RVI extensions

• Feedback from VideoLAN community fed into RVI proposals

  • dot prod, vector abs-diff (SAD), zip/unzip

• Continued collaboration after VDD 2024

  • Got feedback on signed variants of SAD extension proposal

  • Plan to set up meeting across RISE, RVI Vector SIG and VideoLAN / FFmpeg

  • Goal: early feedback on algorithms instructions would be used in

    • May guide instruction coding (params) and find edge cases *before* ratification 

• RISE presence at FOSDEM 2025

  • Attend RISC-V devroom (thanks Bjorn)

  • Concurrent open-media devroom for in person collaboration

• Community still asking for more diverse hardware

  • Larger VLEN, OOO cores, different IP to cross validate algorithms

Software Optimization Progress

• XNNPACK still a priority

  • Ken Unger (Microchip) patches in flight quantized kernel optimizations for RVV

• PyTorch progress

  • Philip Reams (Rivos) open to collaborating and providing public RISC-V packages

  • Build system issues discussed

• sleef build issues

  • Currently broken for cross-compilation, not an easy fix

• New project hosted on RISE gitlab for Mbed-TLS

  • https://gitlab.com/riseproject/Mbed-TLS 

Developer Images

• Luca Barbato (Gentoo) sent a ROMA II laptop for testing

  • Working to get this booting to check status of graphics stack

• clang-20 released, contains some fixes for auto-vectorization

  • Need to check if this allows zvl256b

• gcc progress made fixing issues raised by Luca, but not ready yet

  • https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115789

• Minor issues with rustc ebuild on RISC-V addressed by Luca

System Libraries Priorities - H1 2025

• High profile, in-demand projects, e.g., Tensorflow, Chromium, etc.

  • Planning to finalize this in next System Libraries meeting Dec 10, 2024

• Instructio timings for optimization guide

  • Potential to use llvm-exegesis to extract these for help with RVV optimizations

• Capture missing vector instructions from multimedia projects [1]

  • Key Idea: Collect gaps in extension opcodes preventing efficient multimedia DSP functions, e.g., no transpose op, no dotprods, missing sign-unsign mults, etc.

  • Work with multimedia developers

• Testing framework for upstream projects

  • Issues raised by vendors and OSS contributors about inconsistent benchmarking

  • Example project + source code with best practices for statistically significant data

• More guest speakers!

2025

Dec 5, 2024

System Libraries Deep Dive

System Libraries Priorities - H1 2024

• SL_00_001 bionic (Done)

• SL_00_006 chromium-zlib (Done)

• SL_01_002 dav1d (In progress)

•  

  • Landed 16bpc blend functions, presented how to contribute RVV to dav1d at VDD https://people.videolan.org/~negge/vdd24.pdf

  • Andes patch pending https://code.videolan.org/videolan/dav1d/-/merge_requests/1735 

• SL_01_003 x264 (In progress)

•  

  • Bytedance added RISC-V support to build system, patches in review
    https://code.videolan.org/videolan/x264/-/merge_requests/155 

• SL_01_004 Pixman (In progress)

•  

  • Samsung added optimized pixel format conversion and blending

• SL_00_006 DPDK (In progress)

•  

  • 14x speed up on CRC operations from Bytedance

Developer Images

• Latest image based on Bianbu 2.0 and can be found here [1]

•  

  • Boots Banana Pi BPI-F3 and possibly other k1/m1 based boards

  • Clang-19.1.2

• Past experiments results

•  

  • clang-20 snapshots fail to build [2]

  • gcc-15 still has problems, but it is reported that gcc-trunk has the alignment problems fixed.

  • The rust build system seems to fail to pick the Gentoo cross compiler put in config.toml (I'll investigate further why)

• Presented these images at the RISC-V 101 session and RVI devboard sig [3]

[1] https://dev.gentoo.org/~lu_zero/riscv/gentoo-linux-k1_dev-sdcard-2.0.img.xz 

[2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115789

[3] https://people.videolan.org/~negge/riscv101.pdf 

Proposed RVV instructions for Multimedia

• Initially discussed at RISC-V Summit EU 2024

•  

  • Key Idea: Many implementers noticed the same ISA gaps porting multimedia libraries

• Bytedance created a wiki page to track these instructions:
  https://lf-rise.atlassian.net/wiki/spaces/HOME/pages/8588516/RISCV64+new+vector+instructions+requirements+for+video+multimedia

•  

  • Vector transpose

  • Absolute difference

  • Zero-extended vmv.x.s

  • Rounded Shift Right Narrow,

  • Signed saturate and Narrow to Unsigned

• Did a call for RISC-V Multimedia Instruction Wishlist at VDD 2024:
  https://docs.google.com/presentation/d/16r4pT3YfI1UL5nX3na5SAnZ1DtHglbVPy64oPexwoN8/

•  

  • Collected 3 pages of notes, many overlap above

  • Signed to unsigned, e.g. vnclipsu

  • Changing SEW while preserving the ratio of LMUL

  • Changing rounding mode is slow on Kendryte K230 and SpacemiT K1

  • Missing integer absolute difference instruction, e.g., vabs (equiv. of vfabs)

Limited usage of register based vsetvl is OK

• Optimization guide cautions against using vsetvl

Open

• Long discussion with hardware engineers at LLVM Dev Meeting Santa Clara

•  

  • Under some circumstances it is OK to use vsetvl, e.g., as in dav1d

  • May be possible to use this in auto-vectorization loop unrolling to “fold” the tail so it shares the same code as main body, potentially reducing cost of enabling RVV

Register Pressure Example - 16bpc blend

Recall…

  vwmulu.vv v24, v8, v16

  vwmulu.vv v8, v12, v20

Section 5.2 Vector Operands

Open

System Libraries Priorities - H1 2025

• High profile, in-demand projects, e.g., Tensorflow, Chromium, etc.

•  

  • Planning to finalize this in next System Libraries meeting Dec 10, 2024

• Instruction timings for optimization guide

•  

  • Potential to use llvm-exegesis to extract these for help with RVV optimizations

• Capture missing vector instructions from multimedia projects [1]

•  

  • Key Idea: Collect gaps in extension opcodes preventing efficient multimedia DSP functions, e.g., no transpose op, no dotprods, missing sign-unsign mults, etc.

• Testing framework for upstream projects

•  

  • Issues raised by vendors and OSS contributors about inconsistent benchmarking

  • Example project + source code with best practices for statistically significant data

• More guest speakers!

Nov 7, 2024

Compilers and Toolchains Deep Dive (GCC)

• Good progress on Cactu optimization for spec.  Parts of this work will likely land upstream in the next week or two

• “Bf16” support complete & integrated

• Tons of work on saturating arithmetic done & integrated

• Various codegen adjustments in the vector space have been integrated

•  

  • Many more coming from Robin & myself

• Glibc has accepted first vector ifunc’d mem* routine.  Can adjust SiFive & Rivos implementations trivially and integrate

• CRC work – still not integrated.  Engineers chasing down one final issue before integration

• Function multi-versioning submitted, going through review

• GCC 15 feature freeze next week!

• 20242H Compilers/Toolchains projects

Compilers and Toolchains Deep Dive (LLVM)

• Full register move instructions depend on vtype

•  

  • Kernel setting v-ill at syscall points

  • Some concern that designs behave differently

  • Code generation implications, though perhaps not that bad?

• Function Multi-versioning complete & integrated

• Separate shrink wrapping ready for external review

•  

  • Moves prologue/epilogue code to lesser executed positions within a function

  • Behavior looks good, particularly on perlbench & gcc in spec

• Stack-clash – engineer busy, Craig recommends posting for review anyway

• No updates on CRC, autovect (multiple), landing pads, openmp

• 20242H Compiler/Toolchain Projects

Distro and Integration Deep Dive

• Active group discussions

  • Ubuntu will be shipping RVA23 for all forthcoming releases

  • Fedora is currently at RVA20 “due to lack of hardware” (This is being taken back to the Fedora Council for discussion)

•  

  • Baseline profile for distros

• Actively recruiting members from Alma Linux for coordination of Python packagin

Oct 31, 2024

Kernel and Virtualization Working Group Deepdive 31/10/2024

What’s merged for Linux-6.13 ?

•  

  • Linux-6.13-rc1 will be available 1st week of December 2024
    
    
    

  • Noteworthy stuff merged for Linux-6.13:

• Linux RISC-V

•  

  •  

    •  

      • RISC-V IOMMU driver using device-tree

      • Userspace pointer masking and tagged address ABI

      •  

        • Support for Smnpm, Ssnpm, and Supm extensions

      • Support for Svade and Svadu extensions

• KVM RISC-V

•  

  •  

    • Host nested acceleration using SBI NACL

    • Perf support to collect KVM guest statistics

    • Virtualize Smnpm and Ssnpm extensions

    • Virtualize Svade and Svadu extensions

RVA23 profile: Discovery updates

• HWPROBE additions in Linux-6.13

•  

  • Supm

• KVM ONE_REG additions in Linux-6.13

•  

  • Smnpm, Ssnpm, Svade, and Svadu

• Kernel HWPROBE (31-10-2024, wiki)

•  

  • NA - 47 (50%), TBD - 7 (7.45%), COMPLETED - 40 (42.55%), TOTAL - 94

• KVM ONE_REG (31-10-2024, wiki)

•  

  • NA - 17 (18.08%), TBD - 23 (24.47%), COMPLETED - 54 (57.45%), TOTAL - 94

2023-2H: Project updates

• 2023-2H: Recently upstreamed projects

• LK_01_007 - IOMMU driver with DT support

• 2023-2H: Development status (31-10-2024, wiki)

• COMPLETED - 25 (100%), TOTAL - 25

• 2023-2H: Upstreaming status (31-10-2024, wiki)

•  

  • TBD - 1 (4%), COMPLETED - 24 (96%), TOTAL - 25

2024-1H: Recently development completed projects

• LK_02_025 - KVM System Suspend virtualization

• LK_03_008 - QEMU-KVM AIA userspace irqchip_split support

• LK_03_032 - KVMTOOL System Suspend support

• LK_03_033 - QEMU-KVM System Suspend support

2024-1H: Recently upstreamed projects

• LK_02_008 - KVM Nested acceleration

•  

  • LK_03_022 - KVMTOOL Zawrs support

• 2024-1H: Development status (31-10-2024, wiki)

  • TBD - 2 (4.08%), ONGOING - 1 (2.04%), COMPLETED - 46 (93.88%), TOTAL - 49

• 2024-1H: Upstreaming status (31-10-2024, wiki)

•  

  • TBD - 3 (6.12%), ONGOING - 8 (16.33%), COMPLETED - 38 (77.55%), TOTAL - 49

2024-2H: Project updates

• 2024-2H: Recently upstreamed projects

• LK_01_021 - Svadu support in kernel

•  

  • LK_01_037 - Userspace Pointer Masking and tagged address ABI

  • LK_01_042 - Optimize memory fences using Svvptc extension

  • LK_02_017 - KVM Svadu virtualization

  • LK_02_026 - KVM Pointer Masking virtualization

• 2024-2H: Development status (31-10-2024, wiki)

  • TBD - 21 (58.33%), ONGOING - 2 (5.55%), COMPLETED - 13 (36.12%), TOTAL - 36

• 2024-2H: Upstreaming status (31-10-2024, wiki)

  • TBD - 29 (80.56%), ONGOING - 2 (5.55%), COMPLETED - 5 (13.89%), TOTAL - 36

Oct 17, 2024

Firmware Deep Dive

• 8 Projects in 2024 2H.

  • SECFW_00_01 - Reference RPMI implementation librpmi

  • SBI_00_06 - OpenSBI RPMI support

  • SBI_00_07 - OpenSBI MPXY support

•  

  • 5 Projects moved from 2024 1H due to spec dependencies

  • 3 new MPXY/RPMI related projects added.

• OP-TEE repos created under RISE gitlab.

•  

  • Discussion with security WG to move overall charter to it.

• RP010 - EFI IOMMU DXE Driver for RISC-V EDK2

•  

  • Bidding closed.

• Challenges:

•  

  • Spec dependencies to upstream

  • Project pipelin

Oct 10, 2024

Debug and Profiling Deep Dive

• Valgrind

• ISCAS start working on B-ext supportRVV upstreaming requires a unified scalable vector IR design, accommodating both ARM SVE and RVV, POC planned

• Long-term goal is to enable RVA23 and used in OpenEuler riscv port

• GDB

• GDB support for new data types (vector, FP16, BF16), dev is done, upstreaming not started

• LLDB

• Support for optional FP reg dump is merged, used in target CPU such as: RV64IMA

• DynamoRIO

• Support for 2 tracing features get (drcachesim, drcov) merged

• DynamoRIO test & doc enhancement for riscv, merged

• DynamoRIO RVV mem tracing support (dev WIP)

• Perf profiling

• Add perf counter for control transfer record (RFC patch sent)

• Open/Challenges

• lack of active patch review on the RFC patches for advanced PMU features

RISE Developer Infrastructure Update For the October 2024 TSC Deep Dive  October 10, 2024

Topics

• Developer Infrastructure WG Introduction & Vision

• Build Farm

•  

  • 2024Q3 Review

  • Kernel CI Brief Review

  • 2024Q4 Projection

  • Hosting Provider Migration

• Board Farm

• Developer Tools

Developer Infrastructure WG Introduction

• Charter

•  

  • The Developer Infrastructure WG focuses on software and services to support open-source RISC-V developers - both RISE members and the broader open-source community.

• Co-chairs

•  

  • Barna Ibrahim (Rivos)

  • Paul Walmsley (SiFive)

• TSC Contact

•  

  • Nathan Egge (Google)

Developer Infrastructure WG Vision

• Three mutually-supporting projects

•  

  • RISE Build Farm (Active)

  • RISE Board Farm (Inactive)

  • RISE Developer Tooling (Active)

• Goal

•  

  • Provide robust development infrastructure and tools to RISC-V developers

RISE Build Farm: Introduction

•  

  • Objective

  •  

    • Cross-build and test (in simulation) RISC-V ports of key open source software

  • Running in Google Cloud

  • Björn Töpel (Rivos) coordinating

  • Brian “Redbeard” Harrington (Red Hat): co-admin

  • Status

• Nine active projects 

•  

  •  

    • ~18 active large VM instances on GCP

    • Mostly acting as Github Runner performing cross-compilation/qemu-system-riscv{32,64} tests

Build Farm: 2024Q3 Review (1 of 2)

• Eight existing projects running

•  

  • RISE GCC pre-commit CI (Patrick O'Neill, Edwin Lu)

  • RISE GCC post-commit CI (Patrick O'Neill, Edwin Lu)

  • RISE GCC fuzzer CI (Patrick O'Neill, Edwin Lu)

  • RISE GCC microcontroller CI (Patrick O'Neill, Edwin Lu)

  • RISE GLIBC pre-commit CI (Patrick O'Neill, Edwin Lu)

  • RISE LLVM fuzzer CI (Patrick O'Neill, Edwin Lu)

  • RISE Linux Kernel CI (Björn Töpel)

  • RISE Python Wheels (Mark Ryan)

Build Farm: 2024Q3 Review (2 of 2)

• One existing project shut down

  • Caused by technical issues that no one had the time to debug

•  

  • RISE GLIBC post-commit runner (Edwin Lu, Patrick O’Neill)

• One new project added

•  

  • RISE QEMU Aarch64 test system (Paul Walmsley, Max Chou)

Build Farm: Value

• Thousands of builds, and millions of tests per month on key, foundational RISC-V open source projects

•  

  • GCC, LLVM, Linux kernel, GLIBC, Python

• > 150 toolchain bugs found via our fuzzer instances

Build Farm: Linux Kernel CI

• https://github.com/linux-riscv/

• Managed by Björn Töpel

• Two flavors

•  

  • Pre-commit (patchwork/mailing lists)

  • Post-commit (important branches, build/boot/test multiple configurations)

• More configurations added: ACPI

• More tests added: LTP, kselftest

RISE Board Farm

• Objective

  • Many use cases: OpenJDK, Linux distributions, kernel, Go(?) …

•  

  • Provide a range of Linux-capable RISC-V boards to run functionality and performance tests on CI-generated code

  • Investigate future feasibility of providing developer access to boards

• Status

•  

  • No significant progress in 2024Q3

  • Build Farm efficiency work and relocation planning taking up all available management bandwidth

  • Volunteers solicited!

RISE Developer Tools

• Objective

  • Ideally combines cross and native development environment and native system software and userspace

•  

  • Provide a full Linux system image build, boot, and development environment for use on both simulators (QEMU) and RISC-V hardware

• Status

  • Luca Barbedo putting in a lot of effort here

•  

  • Nathan’s Gentoo build available for general use with cutting-edge software included

  • How to productize/test?

Credits

• Barna Ibrahim (Rivos): Co-chair

• Björn Töpel (Rivos): Kernel CI Build Farm Project Admin, Build Farm Lead

• Brian ‘redbeard’ Harrington (Red Hat): Build Farm Administrator

• Edwin Lu (Rivos): Toolchain Build Farm Project Admin

• Nathan Egge (Google): TSC contact, Developer Tools Lead

• Patrick O’Neill (Rivos): Toolchain Build Farm Project Admin

• Paul Walmsley (SiFive): Co-chai

Sep 26, 2024

System Libraries Priorities - H1 2024

• SL_00_001 bionic (Done)

• SL_00_006 chromium-zlib (Done)

• SL_01_002 dav1d (In progress)

•  

  • GSoC student optimized 115 functions w/ RVV 1.0 - 17% reduction in decode time

  • Fixed several RISC-V specific checkasm issues

• SL_01_003 x264 (In progress)

•  

  • Bytedance added RISC-V support to build system, optimizations in progress

• SL_01_004 Pixman (In progress)

•  

  • Samsung added optimized pixel format conversion and blending

• SL_00_006 DPDK (In progress)

•  

  • 14x speed up on CRC operations from Bytedance

• SL_00_004 BoringSSL (In progress)

•  

  • Google developer working on porting OpenSSL routines to BoringSSL

RFP Update

• RP002 - Optimize H.264 Decoding in FFmpeg

  • Commit fa5a605 avcodec/riscv: add h264 dc idct rvv

  • Commit 8280ec7 lavu/riscv: fall back on clock_gettime()

  • Commit e758b24 checkasm: add wildcompares for test & functions

•  

  • Landed iDCT functions using RVV (8-, 9-, 10-, 12- and 14-bit)

  • Landed improvements to checkasm framework

• RP005 - Add QEMU TCG support for V and Zvk

  • Have micro benchmarks and analyzing via profiler on qemu x86_64 binary

  • Patches in flight 

  • https://lists.gnu.org/archive/html/qemu-devel/2024-09/msg03570.html

  • AOSP boot time now in line with scalar, enables vector code in CI / CD

•  

  • Focused on RISC-V Vector v ARM SVE comparison for mem* and str* operations

  • Separately, Max Chou (SiFive) posted updated v6 QEMU patch to the mailing list

Unmodified QEMU, scalar: ~10 minutes

Unmodified QEMU, vector: ~20 minutes

Modified QEMU, scalar: ~10 minutes

Modified QEMU, vector: ~10 minutes

Gentoo Developer Images

• Abstract to RISC-V NA Summit rejected [1]

•  

  • Presented at Bay Area RISC-V Meetup on Aug-15 [2]

• Key Idea: Automate developer image building

•  

  • Now takes only ~300 minutes (!) to cross compile bootable image

  • U-Boot + Kernel + ~330 software packages

  • Bespoke CFLAGS possible, testing surfaced several gcc autovector issues [3]

• Partnered with Luca Barbato, RISC-V Gentoo developer

•  

  • Fixed multiple issues unblocking full cross compilation <-- no other distro has this

  • Luca presented this work at the Sept-17 System Libraries WG meeting [4]

  • Joint blog post in-progress to post on RISE website

[1] https://people.videolan.org/~negge/rvi2024na.pdf 

[2] https://people.videolan.org/~negge/riscv_meetup.pdf 

[3] GCC Bug 116242 - [meta-bug] Tracker for zvl issues in RISC-V

[4] RISC-V Developer Images

System Libraries Priorities - H2 2024

• SL_03_002 Tensorflow

•  

  • Bytedance fixed RISC-V build issues using bazel, effort to optimize more routines

• Instruction timings for optimization guide

•  

  • Potential to use llvm-exegesis to extract these for help with RVV optimizations

• Capture missing vector instructions from multimedia projects [1]

•  

  • Key Idea: Collect gaps in extension opcodes preventing efficient multimedia DSP functions, e.g., no transpose op, no dotprods, missing sign-unsign mults, etc.

• Testing framework for upstream projects

•  

  • Issues raised by vendors and OSS contributors about inconsistent benchmarking

  • Example project + source code with best practices for statistically significant data

• More guest speakers!

[1] https://wiki.riseproject.dev/spaces/HOME/pages/8588516/
RISCV64+new+vector+instructions+requirements+for+video+multimedia

Sep 19, 2024

Attendees:

• Michelle Martineau, The Linux Foundation

• Terje Bergstrom, NVIDIA

• Kumar Sankaran, Ventana

• Alexey Bataev, SiFive

• Jian Xiong, Alibaba

• David Weaver, Akeana

• Robin Randhawa, SiFive

• Brian Harrington, RedHat

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Gordan Markus, Cannonical

• Ming-yu Hung, Mediatek

• Ludovic Henry, Rivos

• Robin Randhawa, SiFiive

• Tim Ouyang, Andes

Agenda:

Language Runtimes Deep Dive led by Ludovic Henry

• Status Update: Java

  • Java 17, 21, 22, 23, and tip are available

  • Java 11 still doesn’t pass public CI yet

  • More and more vectorized intrinsics: base64, crc32, chacha20, adler32 

  • Better code lowering: rounding, reverse bytes, rotate left/right, unsigned comparisons, shift left/right, vector-scalar/vector-immediate bitwise logic, count leading/trailing zeros, popcount, casting

•  

  • LR_00_007: Distribute Java 11 + 17 + 21 in Adoptium

  • LR_00_001: Improve support for Vector extension in OpenJDK

  • LR_00_027: Implement aes encode/decode intrinsics - WIP

  • LR_00_030: Implement Base64 intrinsics - Done

• Status Update: Go

  • Depends on availability of RVV 1.0 hardware on Scaleway

•  

  • LR_02_007: Accelerate crypto/sha256 and crypto/sha512 with hand-written assembly [RFP001] - Done

  • LR_02_024: Use Bitmanip instruction in compiler where optimal [RFP001] - Done

  • LR_02_005: Accelerate math/big with hand-written assembly [RFP001] - 95% Done

  • LR_02_002: Support for Vector extension in Go Assembler [RFP001] - WIP

  • LR_02_027: Support for Vector Crypto extensions in Go Assembler [RFP001] - WIP

  • LR_02_0029: Add RISC-V boards to Go upstream CI

• Status Update: Python

  • pandas, ninja, numpy, scipy, MarkupSafe, optree, psutil, msgpack, cibuildwheel, auditwheel, cmake, PyYAML, pillow, maturin, lintrunner, tlparse, nh3, lxml, cffi, cryptography

  • Registry: https://gitlab.com/groups/riseproject/python/-/packages

  • Based on Ubuntu 22.04

  • Working with them to provide AlmaLinux 10 in RISC-V

•  

  • Distributing packages for RISC-V

  • Dependency on AlmaLinux

• Status Update: Javascript

•  

  • No changes since last update

• Status Update: Rust

  • Bring Linux-RISC-V to tier1 platform

•  

  • Newly supported since last update

  • LR_07_001: Gap Analysis - WIP

• Status Update: WebAssembly

  • WASM SIMD: VLS (128bits vectors)

  • WASM Flexible Vector: VLA, largely inspired by RVV/SVE

•  

  • Newly supported since last update

  • LR_08_001: Support for WASM SIMD

• Work Prioritization

  • Java: https://wiki.riseproject.dev/display/HOME/LR_00%3A+Java

  • Python: https://wiki.riseproject.dev/display/HOME/LR_01%3A+Python

  • Go: https://wiki.riseproject.dev/display/HOME/LR_02%3A+Go

  • Javascript: https://wiki.riseproject.dev/display/HOME/LR_06%3A+Javascript

  • Rust: https://wiki.riseproject.dev/display/HOME/LR_07%3A+Rust

  • WASM: https://wiki.riseproject.dev/display/HOME/LR_08%3A+WebAssembly

•  

  • Wiki is up-to-date

• Please comment on mailing list for prioritization

•  

  • Anything not listed you’d like to see?

  • Anything not as high on the priority list as you expected?

• Scaleway Board Farm

  • Adoptium/Java: 14

  • Go: 1 (waiting on RVV 1.0 hardware)

  • RockyLinux: 5

  • AlmaLinux: 1 (working with RVI for their own boards)

  • Rust: 2

  • WASM: 1

•  

  • 24 machines allocated:

  • Eagerly waiting for RVV 1.0 hardware

• RFP011 - Python packaging

•  

  • Discussed in previous TSC; next steps?

Sep 5, 2024

Attendees:

• Michelle Martineau, The Linux Foundation

• Terje Bergstrom, NVIDIA

• Anup Patel, Ventana

• Alexey Bataev, SiFive

• Jian Xiong, Alibaba

• Mark Zhuang, Spacemt

• Paul Walmsley, SiFive

• Daniel Barboza, Ventana

• David Weaver, Akeana

• Robin Randhawa, SiFive

• Brian Harrington, RedHat

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Gotdan Markus, Cannonical

• Nathan Egge, Google

• Ming-yu Hung, Mediatek

• Zhu Yuan, Bytedance

• Tim Ouyang, Andes

Agenda:

Overall status

2024 projects - not yet sent for review

2024 projects - upstream process ongoing

2024 projects - upstream completed

Projects not sent yet for review:

• SE_01_018 - QEMU ACPI PPTT support for RISC-V

• Community project (Starfive)

• SE_02_004 - QEMU RVV performance enhancements (Vendor patches)

•  

  • RP005 RISE wiki page,  weekly status: github link

  • Latest version from Max Chou: RFCv5

• SE_01_003 - QEMU WorldGuard support

•  

  • Latest version: v1

• SE_01_004 - QEMU IOPMP support

•  

  • Latest version:  v8

• SE_01_015 - QEMU RISC-V IOMMU support

•  

  • Latest version: v7

• SE_01_017 - QEMU ACPI SPCR support for RISC-V (no change)

•  

  • Latest version: v2

  • Community project (Starfive)

• SE_01_021 - QEMU RVA23 profile support (no change)

•  

  • List of missing extensions: sig-qemu message

  • Some of them already landed for review

• SE_01_022 - RISC-V Server SoC Reference Board (no change)

•  

  • New project

  • Latest version: v2

• SE_01_005 - QEMU PCIe passthru on x86 hosts  (no change)

•  

  • Latest version:  v1

• SE_01_019 - QEMU ACPI SRAT/SLIT(NUMA) support for RISC-V

•  

  • Available in QEMU 9.0

• SE_01_020 - QEMU SMBIOS support for RISC-V

•  

  • Available in QEMU 9.0

Aug 22, 2024

Attendance

• Alexey Bataev, SiFive

• Evan Harrison, The Linux Foundation

• Nathan Egge, Google

• Anup Patel, Ventana

• Brian Harrington (Redbeard), Redhat

• Daniel Barboza, Ventana

• David Weaver, Akeana

• Erich Hanke, AMD

• Gordon Markus,

• Jian Xiong, Alibaba

• Kumar Sankaran, Ventana

• Ludovic Henry, Rivos

• Mark Zhuang, SpaceMIT

• Ming-Yu, MTK

• Paul Walmsley, SiFive

• Simon Harvey, Img Tech

• Sunil V L, Ventana

• Tim Ouyang, Andes

• Tomas Evensen, AMD

• Zhu Yuan, Bytedance

• Victor Costan, Google

Agenda

• Kernel and Virtualization Deep Dive led by Anup Patel

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Kernel and Virtualization Deep Dive

Latest Linux release updates

•  

  • Linux-6.11-rc4 available this week on kernel.org and final Linux-6.11 will be available in September 2024
    
    
    

  • Noteworthy stuff already merged for Linux-6.11:

• Linux RISC-V

•  

  •  

    •  

      • Memory Hot(Un)plug

      • ACPI SMBIOS/DMI, SPCR, PPTT, and NUMA support

      • Performance improvements and cleanups for text patching

      • Support Zve32[xf] and Zve64[xfd] Vector sub-extensions

      • Use Zawrs for spinlocks when available

      • HWPROBE support for time CSR frequency

      • HWPROBE support for highest user-space virtual address

      • HWPROBE support for Zimop, Zcmop, Zca, Zcf, Zcd, Zcb, and Zawrs extensions
        
        
        

• KVM RISC-V

•  

  •  

    • AIA IMSIC HW guest file support

    • Perf KVM stat support

    • Virtualize Zawrs for guest

    • ONE_REG support for Zimop, Zcmop, Zca, Zcf, Zcd, Zcb, and Zawrs extensions

RVA23 profile: Discovery updates

• HWPROBE additions in Linux-6.11

•  

  • Zimop, Zcmop, Zcb, Zawrs

  • Highest virtual address for user-space

• KVM ONE_REG additions in Linux-6.11

•  

  • Zimop, Zcmop, Zcb, Zawrs

• Kernel HWPROBE (22-08-2024, wiki)

•  

  • NA - 33 (39.76%), TBD - 7 (8.43%), COMPLETED - 43 (51.81%), TOTAL - 83

• KVM ONE_REG (22-08-2024, wiki)

•  

  • NA - 10 (12.05%), TBD - 20 (24.10%), COMPLETED - 53 (63.85%), TOTAL - 83

2023-2H: Project updates

• 2023-2H: Projects moved to 2024-2H due to SBI v3.0 dependency

• LK_01_005 - Native/hosted debug support

• LK_02_011  - KVM Native/hosted debug virtualization
  
  

• 2023-2H: Recently upstreamed projects

• LK_00_005 - Memory Hot(Un)plug

•  

  •  

    • LK_02_003 - KVM AIA IMSIC guest file support
      
      

• 2023-2H: Development status (22-08-2024, wiki)

• COMPLETED - 25 (100%), TOTAL - 25

• 2023-2H: Upstreaming status (22-08-2024, wiki)

•  

  • TBD - 1 (4%), ONGOING - 3 (12%), COMPLETED - 21 (84%), TOTAL - 25

2024-1H: Project updates

• 2024-1H: Recently upstreamed projects

• LK_01_015  - PMU snapshot support

• LK_01_019  - Zawrs support

• LK_01_029 - ACPI NUMA support

• LK_01_030 - ACPI PPTT support

• LK_01_035 - ACPI SPCR support

• LK_01_036 - ACPI SMBIOS support

• LK_01_040 - CRC API optimization using Zbc extension

• LK_02_010 - KVM PMU snapshot virtualization

• LK_02_015 - KVM Zawrs virtualization

• LK_02_022 - KVM Perf sampling support for guest

• LK_03_009 - QEMU-KVM debug console support

• LK_03_028 - KVMTOOL Zacas support

• LK_03_029 - QEMU-KVM Zacas support

• 2024-1H: Development status (22-08-2024, wiki)

  • TBD - 4 (8.7%), ONGOING - 1 (2.17%), COMPLETED - 41 (89.13%), TOTAL - 46
    
    

• 2024-1H: Upstreaming status (22-08-2024, wiki

  • TBD - 6 (13.04%), ONGOING - 4 (8.7%), COMPLETED - 36 (78.26%), TOTAL - 46

2024-2H: Priorities

• Kernel

•  

  • ISA Extensions

  •  

    • Supervisor Counter delegation (Ssccfg) based perf driver

    • Control Transfer Record (Ssctr) support in perf driver

    • Pointer Masking (Ssnpm) support

    • Quality of Service (CBQRI and Ssqosid) support

  • ACPI improvements

  •  

    • ACPI RISC-V IOMMU Table (RIMT) support

    • ACPI support for IOMMU driver

    • ACPI RAS support (incl. APEI and SBI SSE notifications)

  • SBI v3.0

  •  

    • Firmware feature (FWFT) support

    • Supervisor software events (SSE) support

    • Debug Triggers (DBTR) (aka native/hosted debug) support

    • Message Proxy (MPXY) support

    • Perf event discovery using SBI PMU extension

• KVM

•  

  • ISA Extensions

  •  

    • Virtualize Control Transfer Record (Ssctr) for Guest

    • Virtualize Pointer Masking (Ssnpm) for Guest

    • Virtualize Quality of Service (CBQRI and Ssqosid) for Guest

  • Nested virtualization (trap-n-emulate H-extension)

  • Virtualize SBI v3.0

  •  

    • Firmware feature (FWFT) support for Guest

    • Supervisor software events (SSE) support for Guest

    • Debug Triggers (DBTR) (aka native/hosted debug) support for Guest

    • Message Proxy (MPXY) support for Guest

    • Virtualize perf event discovery using SBI PMU extension for Guest

Aug 1, 2024

Attendees:

• Michelle Martineau, The Linux Foundation

• Terje Bergstrom, NVIDIA

• Alexey Bataev, SiFive

• Keeran Rothenfusser, Rivos

• Barna Ibrahim, Rivos

• Kumar Sankaran, Ventana

• Tim Ouyang, Andes

• Zhu Yuan, Bytedance

• Paul Walmsley, SiFive

• Brian Herrington, Red Hat

• Victor Costan, Google

Agenda:

• System Libraries Deep Dive led by Nathan Egge

• Developer Infrastructure Deep Dive led by Paul Walmsley

• WG Opens 

• RFPs

• Future topics: WG Opens/challenges

• AIs from last week

System Libraries Deep Dive- Keeran RothenFusser

System Libraries WG Charter

• Accelerate adoption of RISC-V in open source system libraries by focusing on high-leverage initiatives that unblock upstream projects and bring RISC-V to the same level of functionality and performance as the rest of the OSS ecosystem.

• In scope:

•  

  • Open source tooling

  • Best practice guides

  • Case studies

  • Writing software optimizations

  • Performance benchmarking

  • Dependency analysis

• System Libraries contain potentially 1000’s of OSS projects

•  

  • RISE cannot write all the code to enable entire ecosystem

System Libraries Priorities

• SL_00_004 BoringSSL (In progress)

•  

  • Google developer working on porting OpenSSL routines to BoringSSL

• SL_01_001 libflac (In Progress)

•  

  • Pull request got a nudge, now that more hardware available 

• SL_01_002 dav1d (In progress)

•  

  • GSoC student currently adding more RVV 1.0 optimizations

• SL_01_003 x264 (In progress)

•  

  • Bytedance working on adding RVV 1.0 optimized routines

• SL_03_001 XNNPACK (In progress) 

•  

  • Imagination working on adding RVV 1.0 optimized routines

• Trial run the upstream developer story

  • Examples include

  •  

    • Regression: GCC emitting illegal unaligned loads

  • Check that vendor kernels support needed tooling

  •  

    • Backported perf for K230

    • SpacemiT missing PMU counters

•  

  • Assume the role of early adopter and find issues before they hit community

  • Continue to test hardware when it comes out for suitability

• Run experiments verify software optimizations working as intended

•  

  • Mailing list seen discussion on performance of in-register data movements

• Produce artifacts usable for upstream development

  • https://github.com/negge/bespokeOS/tree/master 

  • Rebuild everything from source for RISC-V (issues encountered)

•  

  • Bootable system images with up-to-date toolchains

  • Performance testing and CI tooling

RFP Update

• RP002 - Optimize H.264 Decoding in FFmpeg

  • https://git.ffmpeg.org/gitweb/ffmpeg.git/commit/8280ec7 

•  

  • Using K230 and Gentoo developer image for development / testing

  • Wrote prediction and iDCT functions using RVV (8-, 9-, 10-, 12- and 14-bit)

  • Patches up for review https://code.videolan.org/jdek/ffmpeg/-/merge_requests/2 

  • Updated ffmpeg checkasm to use clock_gettime()  over RDTIME instruction 

  • Meeting with vendor on Friday and hope to get a full report of implemented functions

• RP005 - Add QEMU TCG support for V and Zvk

  • https://github.com/embecosm/rise-rvv-tcg-qemu-reports/blob/main/20240731.md 

  • https://patchew.org/QEMU/20240717133936.713642-1-max.chou@sifive.com/ 

•  

  • Weekly reporting on progress

  • Work is progressing, 60x improvement based on patch set v5 by Max Chou (SiFive)

Benchmarking improvements to QEMU

• RP005 Add QEMU TCG support for V and Zvk started May 1st 2024

•  

  • Weekly progress reports https://github.com/embecosm/rise-rvv-tcg-qemu-reports

• Can we (this body) verify these changes?

•  

  • Booting AOSP 4 weeks ago with Max Chou patchset v4 [1] showed no improvement
    [1] https://lore.kernel.org/all/20240613175122.1299212-1-max.chou@sifive.com/ 

Guest Speaker Series

Invite experts to present RISC-V SW ecosystem challenges and successes. Had a good turnout, and also lots of guest speakers in May and June. Since last deep-dive

• March 19th: Nick Brown - Edinburgh Parallel Computing Centre

•  

  • RISC-V and HPC, What do we need from the software ecosystem?

• May 14th: Adenilson Cavalcanti - Intel / Chromium

•  

  • RVV Optimizations for Chromium zlib

• May 28th: Chris Taylor - Tactical Computing Labs

•  

  • An Introduction HPX an Asynchronous Many-Task Runtime System

• June 25th: Yuan Zhu - Bytedance

•  

  • Optimizing x264 encoder for RISC-V

• July 23rd: Filip Wasil - Samsung

•  

  • Updates on RVV efforts 

  • Contributions to upstream projects

  • Questions around benchmarking and performance analysis as more hardware becomes available

RVI EU Summit

• Nathan Egge received the RVI ‘Software Leadership Award’

• Apart from the RISE presentation, got enough mentions in other presentations

• Some of the work from dav1d as part of SL_01_002 presented by Nathan

• Good opportunity for system libraries members to meet up with each other, and to reach out beyond RISE

• Got hands on hardware - e.g. ROMA-II from DeepComputing, BananaPi3 for individual members to hack around on

SL_01_002 - Adding RVV assembly to dav1d

• Diversity of hardware with RVV 1.0!

•  

  • K230 has VLEN=128, SpacmiT K1 has VLEN=256

  • What does this mean for writing vector optimizations?

• Diversity of hardware with RVV 1.0!

•  

  • K230 has VLEN=128, SpacmiT K1 has VLEN=256

  • What does this mean for writing vector optimizations?

• Algorithms that use *less* than a full VLEN are essentially tail only

• The blend_w4 routine operates on blocks 4-wide and N-tall

•  

  • Optimal throughput needs appropriately set LMUL

function blend_8bpc_rvv, ext=v

    li t0, 4

    beq a3, t0, 4f

    li t0, 8

    beq a3, t0, 8f

    li t0, 16

    beq a3, t0, 16f

32: vsetvli zero, a3, e8, m2, ta, ma

    j L(blend_epilog)

16: vsetvli zero, a3, e8, m1, ta, ma

    j L(blend_epilog)

8:  vsetvli zero, a3, e8, mf2, ta, ma

    j L(blend_epilog)

4:  vsetvli zero, a3, e8, mf4, ta, ma

L(blend_epilog):

• Algorithms that use *less* than a full VLEN are essentially tail only

• The blend_w4 routine operates on blocks 4-wide and N-tall

•  

  • Optimal throughput needs appropriately set LMUL

function blend_8bpc_rvv, ext=v

    li t0, 4

    beq a3, t0, 4f

    li t0, 8

    beq a3, t0, 8f

    li t0, 16

    beq a3, t0, 16f

32: vsetvli zero, a3, e8, m2, ta, ma

    j L(blend_epilog)

16: vsetvli zero, a3, e8, m1, ta, ma

    j L(blend_epilog)

8:  vsetvli zero, a3, e8, mf2, ta, ma

    j L(blend_epilog)

4:  vsetvli zero, a3, e8, mf4, ta, ma

L(blend_epilog):

function blend_vl256_8bpc_rvv, ext=v

    li t0, 4

    beq a3, t0, 4f

    li t0, 8

    beq a3, t0, 8f

    li t0, 16

    beq a3, t0, 16f

32: vsetvli zero, a3, e8, m1, ta, ma

    j L(blend_epilog)

16: vsetvli zero, a3, e8, mf2, ta, ma

    j L(blend_epilog)

8:  vsetvli zero, a3, e8, mf4, ta, ma

    j L(blend_epilog)

4:  vsetvli zero, a3, e8, mf8, ta, ma

    j L(blend_epilog)

• With vector length specific (VLS) implementations specialized on VLEN

Kendryte K230

blend_w4_8bpc_c:   204.5 ( 1.00x)

blend_w4_8bpc_rvv:    56.4 ( 3.62x)

blend_w8_8bpc_c:   608.6 ( 1.00x)

blend_w8_8bpc_rvv:    87.3 ( 6.97x)

blend_w16_8bpc_c: 2363.8 ( 1.00x)

blend_w16_8bpc_rvv: 225.1 (10.50x)

blend_w32_8bpc_c: 5990.3 ( 1.00x)

blend_w32_8bpc_rvv: 518.8 (11.55x)

SpacemiT K1

blend_w4_8bpc_c:   201.6 ( 1.00x)

blend_w4_8bpc_rvv:    58.0 ( 3.48x)

blend_w8_8bpc_c:   595.1 ( 1.00x)

blend_w8_8bpc_rvv:    82.1 ( 7.25x)

blend_w16_8bpc_c: 2308.8 ( 1.00x)

blend_w16_8bpc_rvv: 189.0 (12.22x)

blend_w32_8bpc_c: 5853.1 ( 1.00x)

blend_w32_8bpc_rvv: 339.5 (17.24x)

DevInfra WG Collaboration

• Goal: Provide weekly drops of SD images that “just work” on currently available dev board hardware (RVV 1.0 only): K230, BPI-F3, ROMA II

  • Potential to build with exact CFLAGS matching hardware, e.g.,
    -march=rv64gcv --riscv-v-vector-bits-min=256

  • This would produce optimized builds for all packages

•  

  • Use vendor provided image (u-boot, opensbi, kernel)

  • Replace rootfs with gentoo image

  • Future work, could rebuild kernel using more optimizations

• Potential to build with other options

•  

  • Gentoo supports glibc and musl, OpenRC and systemd

  • Can provide a head (Desktop Environment) for ROMA II laptop images

Developer Infrastructure Deep Dive- Paul Walmsley

Developer Infrastructure WG Introduction

• Charter

•  

  • The Developer Infrastructure WG focuses on software and services to support open-source RISC-V developers - both RISE members and the broader open-source community.

• Co-chairs

•  

  • Barna Ibrahim (Rivos)

  • Paul Walmsley (SiFive)

• TSC Contact

•  

  • Nathan Egge (Google)

Developer Infrastructure WG Vision

• Three mutually-supporting projects

•  

  • RISE Build Farm (Active)

  • RISE Board Farm (Active)

  • RISE Developer Tooling (In planning)

• Goal

•  

  • Provide robust development infrastructure and tools to RISC-V developers

RISE Build Farm: Introduction

• Objective

•  

  • Cross-build and test (in simulation) RISC-V ports of key open source software

• Running in Google Cloud

• Björn Töpel (Rivos) coordinating

• Brian “Redbeard” Harrington (Red Hat) doing much of the work

• Status

9 active projects 2 since last quarter

•  

  • Thousands of builds, and millions of tests per month

  • ~100 toolchain bugs found via our fuzzer instances

Build Farm: 2024Q2 Review

• Seven existing projects still running

•  

  • GCC pre-commit CI expanded: Patrick O’Neill & Edwin Lu (Rivos)

• Two new projects added

•  

  • Glibc pre-merge CI: Edwin Lu & Patrick O’Neill (Rivos)

  • GCC microcontroller CI: Patrick O’Neill & Edwin Lu (Rivos)

• New Jenkins infrastructure available for projects to use

RISE Board Farm: Introduction

• Objective

  • Many use cases: OpenJDK, Linux distributions, kernel, Go(?) …

•  

  • Provide a range of Linux-capable RISC-V boards to run functionality and performance tests on CI-generated code

  • Investigate future feasibility of providing developer access to boards

• Curtis Galloway (Google) coordinating

RISE Board Farm: Status

• No significant progress in 2024Q2

• Build Farm efficiency work and relocation planning taking up all of the available management bandwidth

RISE Developer Tools: Introduction

• Objective

  • Ideally combines cross and native development environment and native system software and userspace

•  

  • Provide a full Linux system image build, boot, and development environment for use on both simulators (QEMU) and RISC-V hardware

• Will start with Nathan’s Gentoo build

• No one yet coordinating

•  

  • Some discussion taking place between Nathan and Redbeard on paths forward

Credits

• Barna Ibrahim (Rivos): Co-chair

• Björn Töpel (Rivos): Kernel CI Build Farm Project Admin, Build Farm Lead

• Brian ‘redbeard’ Harrington (Redhat): Build Farm Administrator

• Curtis Galloway (Google): Board Farm Lead

• Edwin Lu (Rivos): Toolchain Build Farm Project Admin

• Ludovic Henry (Rivos): Language Runtimes Build Farm Project Admin

• Patrick O’Neill (Rivos): Toolchain Build Farm Project Admin

• Paul Walmsley (SiFive): Co-chair

Jun 27, 2024

Attendees:

• Michelle Martineau, The Linux Foundation

• Erich Hanke, AMD

• Alexey Bataev, SiFive

• Robin Randhawa, SiFive

• Sunil Vl, Ventana

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Ludovic Henry, Rivos

• Jian Xiong, Alibaba

• Barna Ibrahim, Rivos

• David Weaver, Akean

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Victor Costan, Google

• Nathan Egge, Google

• Ming-yu Hung, Mediatek

•  Jian Zhang, BOSC

Agenda: 

• Updates

•  

  • Website/blog

  • TSC Accomplishments 1H2024

  • 2 FTE Reporting

  • Security Software Working Group TL Election

• Simulator Emulator Deep Dive led by Daniel Barboza

• WG Opens 

• Future topics: WG Opens/challenges

Simulator Emulator Deep Dive led by Daniel Barboza

• Overall status

•  

  • 2024 projects - not yet sent for review

  • 2024 projects - upstream process ongoing

  • 2024 projects - upstream completed

• Projects not sent yet for review:

  • Project RP005 Add QEMU TCG support for V and Zvk

  • Weekly status: github link

  • Community project (Starfive)

•  

  • SE_02_004 - QEMU RVV performance enhancements (Vendor patches)

  • SE_01_018 - QEMU ACPI PPTT support for RISC-V

• Projects under review:

  • Latest version: v1

  • Latest version:  v7

  • Latest version:  v1

  • Project has dependencies on UBOOT and GRUB

  • Latest version: v4

•  

  • SE_01_003 - QEMU WorldGuard support

  • SE_01_004 - QEMU IOPMP support

  • SE_01_005 - QEMU PCIe passthru on x86 hosts

  • SE_01_015 - QEMU RISC-V IOMMU support

• Projects under review

  • Latest version: v2

  • Community project (Starfive)

  • List of missing extensions: sig-qemu message

  • Some of them already landed for review

  • Latest version: v2

  • Latest version (from Max Chou): RFCv4

•  

  • SE_01_017 - QEMU ACPI SPCR support for RISC-V

  • SE_01_021 - QEMU RVA23 profile support

  • SE_01_022 - RISC-V Server SoC Reference Board

  • SE_02_004 - QEMU RVV performance enhancements

• Projects already merged

  • Available in QEMU 9.0

  • Available in QEMU 9.0

•  

  • SE_01_019 - QEMU ACPI SRAT/SLIT(NUMA) support for RISC-V

  • SE_01_020 - QEMU SMBIOS support for RISC-V

Security Software Working Group Election

The Security Software Technical Lead role will open for election July 1st. The nomination period is open for one week followed by a one week voting period. You may nominate yourself or another member of the RISE TSC (Limit 1 candidate per RISE Sponsor Organization). If you are nominating someone else please confirm their interest prior to nominating them.

Commitment:

1hr/ Month-  Lead Security Software Working Group Meetings 

1hr/Month- Governing Board or TSC Deep Dive Meeting

8hrs/Month- Working Group Leadership

Election Cycle:

• July 1 Nominations start

• July 15 Nominations end

• July 16 Voting starts

• July 23 Voting ends

• July 24 Winner announced

Term: July 24, 2024- July 24, 2025

Jun 20, 2024

Attendees:

• Michelle Martineau, The Linux Foundation

• Andrei Warkentin, Intel

• Daniel Barboza, Ventana

• Barna Ibrahim, Rivos

• Jeff Law, Ventana

• Andrew Del Los Reyes, Rivos

• Kumar Sankaran, Ventana

• Brian Harrington, RedHat

• Nathan Egge, Google

• Tim Ouyang, Andes

• Victor Constan, Google

• Zhu Yuan, Bytedance

Agenda: 

• Distro and Integration Deep Dive led by Redbeard

• Updates

•  

  • Website/blog

  • RVI Summit Lounge

  • TSC Accomplishments 1H2024

  • 2 FTE Reporting

  • Security Software Working Group TL Election

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Distro and Integration Deep Dive

• The distro integration group hosts open discussions about the software needs common to all major Linux distros, Android, and bespoke distros used on embedded devices.  

  1. General discussions and questions about viability of builds with low RAM that aren’t capable of updating packages etc. Not something RISE should dictate. 

  2. In General RISE is contributing to the Open Source Projects and there will not be any requirements/mandates by RISE. any requirements are left it up to the companies and their product offerings.  

•  

  • “Why is it you’re all insistent on having ACPI support?”

  • “What is the minimum amount of RAM a board should have?”

• This group makes its meetings  open to the public (the meeting link is on the groups wiki page).

•  

  • Ensures open collaboration modeled after other libre software projects (Debian, Osmocom, etc). 

  • The community sees the “total cost” of design decisions, not just the hardware ones.

• Recently this has driven two major areas of discussion: 

•  

  • Ensure a consistent boot flow (installation portability across distros)

  • Responsibility for code updates below the OS (e.g. Who is on the hook for security bugs in OpenSBI?)

Website and Blog Update

• HAPPY ANNIVERSARY RISE PROJECT!

• Website updated, now with a blog, events page, separated topic pages, dedicated join page

• Bug reports and comments welcome.

 Security Software Technical Lead Election 

The Security Software Technical Lead role will open for election July 1st. The nomination period is open for one week followed by a one week voting period. You may nominate yourself or another member of the RISE TSC (Limit 1 candidate per RISE Sponsor Organization). If you are nominating someone else please confirm their interest prior to nominating them.

Commitment:

• 1hr/ Month-  Lead Security Software Working Group Meetings 

• 1hr/Month- Governing Board or TSC Deep Dive Meeting

• 8hrs/Month- Working Group Leadership

Election Cycle:

• July 1 Nominations start

• July 15 Nominations end

• July 16 Voting starts

• July 23 Voting ends

• July 24 Winner announced

Term: July 24, 2024- July 24, 2025

May 30, 2024

Attendees:

• Erich Hanke, AMD

• Tomas Evensen, AMD

• Robin Randhawa, SiFive

• Terje Bergstrom, NVIDIA

• Anup Patel, Ventana

• Robin Randhawa, SiFive

• Sunil Vl, Ventana

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Jeff Law, Ventana

• David Weaver, Akean

• Kumar Sankaran, Ventana

• Brian Harrington, RedHat

• Paul Walmsley, SiFive

• Nathan Egge, Google

• Tim Ouyang, Andes

• Ming-yu Hung, Mediatek

•  Jian Zhang, BOSC

Agenda:

• Elected: Debug and Profiling Technical Lead

• Firmware Deep Dive led by Sunil V L

• Proposal for Security Working Group Formation

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Elected: Debug and Profiling Technical Lead

Welcome Xaio Wang! Senior System Software Engineer, Intel and Our new Technical Lead for the Debug and Profiling Working Group. Xiao has worked on different domains of system software, including high performance networking, device virtualization, cross-ISA SW migration, binary translation and compatibility, ISA based SW optimization. Xiao has interest in a wide range of technical topics. Recently Xiao is working on enabling RISCV ISA optimization in the Linux kernel.

Firmware Deep Dive led by Sunil V L

• 12 projects in 2024 1H

• Upstreaming complete projects

•  

  • EDK2_00_16 - Svpbmt support (2023 2H project)

  • SBI_00_04 - Domain Context Switch Support

  • SBI_00_03 - Native/hosted debug support

  • COREBOOT_00_01 - coreboot for SiFive Unmatched

• Development complete, Upstreaming in progress

•  

  • EDK2_00_14 - DynamicTablesPkg support

  • EDK2_00_18 - RISC-V QEMU Server Reference Platform

  • EDK2_00_03 - FdtBusDxe support (Need to host under RISE gitlab)

• Upstreaming not started due to spec dependencies

  • CI support for RISC-V targets in place

  • Roadmap items identified (IOPMP, AIA, SmMTT, FF-A Like ABI etc)

  • IOPMP support in progress by Andes

  • Moving to RISE hosted gitlab

•  

  • EDK2_00_15 - StandaloneMmPkg RPMI MM support

  • OPTEE_00_01 - OP-TEE support

  • SBI_00_05 - OpenSBI RPMI MM Support

  • SBI_00_02 - Firmware-first RAS handling Support

  • EDK2_00_10 - UefiPayloadPkg For RISC-V

• Development in progress

•  

  • COREBOOT_00_02 - coreboot for StarFive VisionFive2

• 2024 2H projects under discussion

•  

  • EDK2_00_04 - Build Size Reduction

  • EDK2_00_05 - Back Trace support

  • EDK2_00_13 - libgcc and libatomic libs

  • SCP like reference FW implementation (based on RPMI/MPXY spec)

• Challenges

•  

  • Spec dependencies.

  • Less number of new project proposals.

09 May 2024 

• Evan Harrison, The Linux Foundation

• Alexey Bataev, SiFive

• Barna Ibrahim, Rivos

• Brian Harrington (Redbeard), Redhat

• Drew Fustini, Tenstorrent

• Jeff Law, Ventana 

• Kumar Sankaran, Ventana

• Mason Li, MedieTek

• Nathan Egge, Google

• Paul Walmsley, SiFive

• Terje Bergstrom, Nvidia

• Tim Ouyang, Andes

• Victor Constan, Google

Agenda

• WG Opens/challenges 

• Future topics

• AIs from last week

Appendix

• 2024 Deep Dive Schedule

•  

  • Please review and inform Evan of any changes needed

• Meeting recording access instructions

• RFP Guide for Technical Leads 

•  

  • Please read if you are a TL for a project.

Working Groups Opens / Challenges

• Tensorflow for RISC-V (email sent to libraries-runtimes WG)

• If yes, what is the latest status? 

• Questions regarding the availability of Tensorflow on RISC-V

• Tried to compile Tensorflow within Ventana and things fail due to missing support for Bazel

• Is anyone from RISE or any upstream company working on Tensorflow?

• x264 for RISC-V discussion

• Bytedance team started work on x264 porting and optimization with RVV1.0

• Repo located here https://code.videolan.org/yintong.ustc/x-264-bd-ventana

• Is anyone from RISE or upstream working on x264? Bytedance would like to collaborate with other work if any

• Working Groups Opens / Challenges

02 May 2024 

• Michelle Martineau, The Linux Foundation

• Erich Hanke, AMD

• Tomas Evensen, AMD

• Anup Patel, Ventana

• Heinrich Schuchardt, Canonical

• Robin Randhawa, SiFive

• Gordan Markus, Canonical

• Sunil Vl, Ventana

• Myungjoo Ham, Samsung

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• David Weaver, Akean

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Victor Costan, Google

• Alexey Bataev, SiFive

• Nathan Egge, Google

• Ludovic Henry, Rivos

• Ming-yu Hung, Mediatek

•  Jian Zhang, BOSC

Agenda

• Language Runtimes Deep Dive led by Ludovic Henry 

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Language Runtimes Deep Dive led by Ludovic Henry 

• Status Update

  • Java

  • LR_00_007: Distribute Java 11 + 17 + 21 in Adoptium

    • Java 21, 22, and tip are available since April

    • Java 17 is close, Java 11 doesn’t pass public CI yet

  • LR_00_001: Improve support for Vector extension in OpenJDK

    • Many improvements to code lowering; casting, rounding, multiply reduction, compare, and other vector intrinsics

•  

  • LR_01_013: Enable pip on riscv64

    • Necessary to run pip install on riscv64; released with 24.0

  • LR_01_015: Enable cibuildwheel on riscv64
    LR_01_017: Package and distribute numpy wheel
    LR_01_020: Package and distribute ninja wheel
    LR_01_008: Package and distribute Scikit-Learn wheel
    LR_01_022: Package and distribute markupsafe wheel
    LR_01_024: Package and distribute psutil wheel
    LR_01_027: Package and distribute Pillow wheel

    • Effort to package and distribute Python packages on RISC-V

    • Can’t be done by upstream project (discussed in previous TSC meetings)

  • Approach approved with LFEU Legal on licensing
    
    Go

  • LR_02_0015: Support for Bitmanip extensions in assembler

  • LR_02_024: Use Bitmanip instruction in compiler where optimal

  • LR_02_002: Support for Vector extension in Go Assembler

  • LR_02_0029: Add RISC-V boards to Go upstream CI

• Work

  • Wiki is up-to-date

    • Java: https://lf-rise.atlassian.net/wiki/display/HOME/LR_00%3A+Java

    • Python: https://lf-rise.atlassian.net/wiki/display/HOME/LR_01%3A+Python

    • Go: https://lf-rise.atlassian.net/wiki/display/HOME/LR_02%3A+Go

    • Javascript: https://lf-rise.atlassian.net/wiki/display/HOME/LR_06%3A+Javascript

    • Anything not listed you’d like to see?

    • Anything not as high on the priority list as you expected?

• Python packaging

  • https://gitlab.com/groups/riseproject/python/-/packages

    • Available: ninja, numpy, scipy, pillow, psutil, PyYAML, optree, MarkupSafe, cmake, ninja

    • Next: scikit-learn

    • https://lf-rise.atlassian.net/wiki/display/HOME/LR_01%3A+Python
      
      
      

  • Python has a JIT now

    • It’s doesn’t support RISC-V

Not a blocker as simply disabled for now

Java releases

• Nothing has changed since last update

  • V8 fully supports Linux-RISC-V and Android-RISC-V

  • SpiderMonkey support Linux-RISC-V

  • Node.JS is still an unknown; anyone wants to check it out and document?

OpenMP

• Interest from Tenstorrent, MicroChip

•  

  • https://github.com/llvm/llvm-project/issues/87026
    
    
    

• More appropriate for Compilers and Toolchains WG?

•  

  • Whoever has the time and resources

HPX

• https://github.com/STEllAR-GROUP/hpx/

• Interest from Tenstorrent

• They have CI for ARM, we should check to add RISC-V

•  

  • Need to figure out if it builds and runs OOTB on RISC-V
    
    
    

• More appropriate for System Libraries WG?

•  

  • Whoever has the time and resources

25 Apr 2024 

• Evan Harrison, The Linux Foundation

• Drew Fustini, Tenstorrent

• Andrew de los reyes (Adlr), RIVOS

• Jeff Law, 

• Victor Constant, Google

• Tomas Evensen, AMD

• Alexey Bataev, SiFive

• Terje Bergstrom, NVIDIA

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akean

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Nathan Egge, Google

• Agenda

• Developer Infrastructure Deep Dive led by Paul Walmsely 

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Developer Infrastructure WG Introduction & Vision

• Build Farm

• 2024Q1 Review

• Next Steps

• Board Farm

• Developer Tools

• Challenges

Developer Infrastructure WG Introduction

Charter

• The Developer Infrastructure WG focuses on software and services to support open-source RISC-V developers - both RISE members and the broader open-source community.

• Co-chairs

• Barna Ibrahim (Rivos)

• Paul Walmsley (SiFive)

• TSC Contact

• Nathan Egge (Google)

Developer Infrastructure WG Vision

• Three mutually-supporting projects

• RISE Build Farm (Active)

• RISE Board Farm (Active)

• RISE Developer Tooling (In planning)

• Goal

• Provide robust development infrastructure and tools to RISC-V developers

RISE Build Farm: Introduction

Objective

• Cross-build and test (in simulation) RISC-V ports of key open source software

• Running in Google Cloud

• Björn Töpel (Rivos) coordinating

Status

• 7 active projects

• Thousands of builds, and millions of tests per month.

• Build Farm: 2024Q1 Review

• Broadened the administration base

• Brian “Redbeard” Harrington (Red Hat) now helping out with general admin tasks

• Björn Töpel now leading the Build Farm

• Four existing projects still running

• Two new projects added

• GCC fuzzer: 

• LLVM fuzzer: 

• Credits currently set to expire on September 12, 2024

• Expiration date just discovered mid-April

• Will discuss with Amber and Lars to see if this can be extended

Build Farm: Looking Forward

• CI/CD Based Controller + Job system

• Projects can include a JenkinsFile in their repo which defines the job requirements.  Makes the jobs portable across Jenkins instances as well  

• Webhook + status integration across GitHub, GitLab, and publishing via host names in the subdomain “di.riseproject.dev”.

• Will make this easy to add more Build Farm projects with greater flexibility

• Members will coordinate with other working groups to solicit other projects and support their onboarding

• Compared to Kubernetes it is much simpler to understand and deploy. 

• Biggest challenges: sheep shearing (setting up credential vaults for API access into secret material, authentication proxies, configuring back end roles & policies to allow for the correct, limited, API calls from Jenkins into GCP using the proper service accounts, ensuring build systems “fail” and recover property upon crashing, that services all recover correctly, etc)

• We Need More Build Farm Projects

• Build farm project growth rate is leveling off

• Let’s get more build farm projects going for future payoffs in better RISC-V ecosystem support for all of us

• Please contact us if you have project ideas - we can help

RISE Board Farm: Introduction

Objective

• Many use cases: OpenJDK, Linux distributions, kernel, Go(?) …

• Provide a range of Linux-capable RISC-V boards to run functionality and performance tests on CI-generated code

• Investigate future feasibility of providing developer access to boards

• Curtis Galloway (Google) coordinating

RISE Board Farm: Status

• Hardware prototype running, based on Kendryte K230

• Software infrastructure in progress

• Target is to remotely load as much of the software on the board as possible 

• Hosting at OSUOSL

• Goal: contract agreed in May (new one needed since RISE hosted by LF EU)

RISE Developer Tools: Introduction

Objective

• Ideally combines cross and native development environment and native system software and userspace

• Provide a full Linux system image build, boot, and development environment for use on both simulators (QEMU) and RISC-V hardware

• Will start with Nathan’s Gentoo build

• No one yet coordinating

18 Apr 2024 

• Michelle Martineau, The Linux Foundation

• Drew Fustini, Tenstorrent

• Erich Hanke, AMD

• Tomas Evensen, AMD

• Anup Patel, Ventana

• Mark Zhuang, SpacemIT

• Heinrich Schuchardt, Canonical

• Terje Bergstrom, NVIDIA

• Gordan Markus, Canonical

• Sunil Vl, Ventana

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akeana

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Victor Costan, Google

• Alexey Bataev, SiFive

• Nathan Egge, Google

• Steve Wanless, RedHat

• Paul Walmsley, SiFive

• Olof Johansson, 

• Jefro, Redhat

• Mason Li, MediaTek

Agenda

• Simulator Emulator Deep Dive led by Daniel Barboza

• WG Chairs: Propose setting a minimum of one live meeting per month for each WG

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Simulator Emulator Deep Dive led by Daniel Barboza

2024 projects - not yet started

• SE_01_003 - QEMU WorldGuard support

• SE_01_021 - QEMU RVA23 profile support

• SE_02_004 - QEMU RVV performance enhancements

2024 projects - in progress, not sent for review

• SE_01_017 - QEMU ACPI SPCR support for RISC-V

• Community project (Starfive)

• SE_01_018 - QEMU ACPI PPTT support for RISC-V

• Community project (Starfive)

• 2024 projects - upstream process ongoing

• SE_01_005 - QEMU PCIe passthru on x86 hosts

• Latest version:  v1

• Project has dependencies on UBOOT and GRUB

• SE_01_004 - QEMU IOPMP support (no change)

• Latest version:  v5

• SE_01_015 - QEMU RISC-V IOMMU support

• Latest version: v2

• Goal: merge it for QEMU 9.1 (July 2024 code freeze)

• SE_01_022 - RISC-V Server SoC Reference Board

• New project

• Latest version: v2

2024 projects - upstream completed

• SE_01_019 - QEMU ACPI SRAT/SLIT(NUMA) support for RISC-V

• SE_01_020 - QEMU SMBIOS support for RISC-V

WG Chairs: Propose setting a minimum of one live meeting per month for each WG

• Propose establishing a one-live-meeting-per-month minimum for all WGs (pjw)

• Even if no topics, would be good to do a status review

• Discussed a few weeks ago at the TSC in the afternoon time slot

• All commenters agreed

• Wanted to bring it up in the morning TSC slot for any additional discussion

11 Apr 2024 

• Evan Harrison, The Linux Foundation

• Drew Fustini, Tenstorrent

• Erich Hanke, AMD

• Tomas Evensen, AMD

• Anup Patel, Ventana

• Mark Zhuang, SpacemIT

• Heinrich Schuchardt, Canonical

• Terje Bergstrom, NVIDIA

• Gordan Markus, Canonical

• Sunil Vl, Ventana

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akean

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Victor Costan, Google

• Alexey Bataev, SiFive

• Nathan Egge, Google

• Steve Wanless, RedHat

• Paul Walmsley, SiFive

• Olof Johansson, 

• Jefro, 

• Mason Li, MediaTek

• Tim O,

Agenda

• Distro and Integration Deep Dive led by Redbeard

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

• Updated Deep Dive Schedule- SEE APPENDIX

Distro and Integration Deep Dive

• Dev Infra WG Opens

• Dev Infra: would like to get Jeff’s signoff as Toolchain & Compiler WG chair for the GCC microcontroller Build Farm proposal

• FYI: RISE build farm infrastructure to build riscv64 python binary wheels. Proposal here. 

• Dev Infra: Björn Töpel (Rivos) & Brian Harrington (Red Hat) taking the lead on RISE Build Farm management (thanks!)

• Open Discussion

Dev Infra & Language Runtimes WG Enabling RISC-V Boards Request

• RISE Scaleway Boards for Language Runtimes WG Proposal 

• Scaleaway:  RISC-V servers in the cloud.

Projects to be first enabled:

• Java/Adoptium: 15 boards to build and test Java 11, 17, 21, and 22. It runs for 2000 hours/week of building and testing

• Go: 5 boards, used exclusively for CI

• AlmaLinux/RockyLinux: 5 boards each, used to build their distributions on RISC-V

Next Steps

• TSC and WG are there other needs?

• Report back to Board in 3 months on usage progress

04 Apr 2024 

• Michelle Martineau, The Linux Foundation

• Drew Fustini, Tenstorrent

• Erich Hanke, AMD

• Tomas Evensen, AMD

• Anup Patel, Ventana

• Mark Zhuang, SpacemIT

• Heinrich Schuchardt, Canonical

• Terje Bergstrom, NVIDIA

• Gordan Markus, Canonical

• Sunil Vl, Ventana

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akean

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Victor Costan, Google

• Alexey Bataev, SiFive

• Nathan Egge, Google

• Steve Wanless, RedHat

Agenda

• Kernel and Virtualization Deep Dive led by Anup Patel

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

• Updated Deep Dive Schedule- SEE APENDIX

Kernel and Virtualization Deep Dive led by Anup Patel

Latest Linux release updates

• Linux-6.8 was released on 10th March 2024 and Linux-6.9 merge window concluded on 25th March 2024

Noteworthy updates:

• RVA23 profile extensions

Updates on discovery

• List of RVA23 profile extensions on wiki in-sync with latest spec

• https://lf-rise.atlassian.net/wiki/display/HOME/RVA23+Profile 

• HWPROBE additions

No updates

• KVM ONE_REG additions

• Ztso and Zacas

Overall status

• Total 83 extensions (04-04-2024, wiki

• Kernel HWPROBE (04-04-2024)

•  

  • NA - 36 (43.37%)

  • TBD - 16 (19.28%)

  • COMPLETED - 31 (37.35%)

• KVM ONE_REG (04-04-2024)

•  

  • NA - 10 (12.05%)

  • TBD - 26 (31.32%)

  • COMPLETED - 47 (56.63%)

2023-2H

Updates on projects

• LK_01_003 - AIA drivers with DT support

•  

  • Development: Completed, Upstreaming: Completed

  • First 8 patches merged in Linux-6.9 and remaining 8 in Linux-6.10

• LK_01_005 - Native/hosted debug support (aka HW breakpoint)

•  

  • Development: Completed, Upstreaming: OnGoing

• LK_02_011 - KVM native/hosted debug virtualization

•  

  • Development: Completed, Upstreaming: TBD

• LK_03_018 - QEMU-KVM vector crypto support

•  

  • Development: Completed, Upstreaming: Completed

• LK_03_019 - QEMU-KVM bitmanip support

•  

  • Development: Completed, Upstreaming: Completed

  • Overall status

Total 27 projects (04-04-2024, wiki)

• Development (04-04-2024)COMPLETED / NOTNEEDED - 27 (100%)

• Upstreaming (04-04-2024)

• TBD - 3 (11.11%)

• ONGOING - 7 (25.93%)

• COMPLETED / NOTNEEDED - 17 (62.96%)

2024-1H

• Updates on priorities

  • HWPROBE discovery for Z* and S* extensions included in RVA23 profile

•  

  • Kernel

  • ISA Extensions

• ACPI improvements

•  

  • ACPI LPI support

  • ACPI CPPC support

  • ACPI PPTT support

  • ACPI NUMA support

  • ACPI SPCR support

• SBI v2.0

•  

  • Steal time support

  • System suspend support

  • Debug console support

  • PMU snapshot support

• KVM

•  

  • KVM selftests

  • KVM unit tests

  • Host nested acceleration (Defined by SBI v2.0)

  • ISA extensions

• ONE_REG discovery for Z* and S* extensions included in RVA23 profile

• Virtualize SBI v2.0 support

•  

  • Steat time support for Guest (incl. KVMTOOL and QEMU-KVM)

  • System suspend support for Guest (incl. KVMTOOL and QEMU-KVM)

  • Debug console support for Guest (incl. KVMTOOL and QEMU-KVM)

  • PMU snapshot support for Guest (incl. KVMTOOL and QEMU-KVM)

• Xen

•  

  • Shared memory and event channel

  • IOMMU driver

  • Updates on projects

• LK_01_011 - ACPI LPI support

•  

  • Development: Completed, Upstreaming: Completed

• LK_01_012 - ACPI CPPC support

•  

  • Development: Completed, Upstreaming: Completed

• LK_01_018 - Optimize bitops using Zb* extensions

•  

  • Development: Completed, Upstreaming: Completed

• LK_02_015 - KVM Zawrs virtualization

•  

  • Development: Completed, Upstreaming: Ongoing

• LK_02_020 - KVM Zacas virtualization

•  

  • Development: Completed, Upstreaming: Completed

• LK_03_003 - KVMTOOL Debug console support

•  

  • Development: Completed, Upstreaming: Completed

• LK_03_012 - KVM selftests improvements

•  

  • arch_timer, demand_paging_test, dirty_log_test, get-reg-list, guest_print_test, kvm_binary_stats_test, kvm_create_max_vcpus, kvm_page_table_test, set_memory_region_test, and steal_time

  • Development: Completed, Upstreaming: Completed

Lists of tests

• LK_03_013 - KVM unit tests RISC-V port

•  

  • Development: Completed, Upstreaming: Completed

• LK_03_020 - KVMTOOL Smstateen support

•  

  • Development: Completed, Upstreaming: Completed

• LK_03_021 - QEMU-KVM Smstateen support

•  

  • Development: Completed, Upstreaming: Completed

• LK_03_022 - KVMTOOL Zawrs support

•  

  • Development: Completed, Upstreaming: TBD

• LK_03_025 - QEMU-KVM Svnapot support

•  

  • Development: Completed, Upstreaming: Completed

• LK_03_028 - KVMTOOL Zacas support

•  

  • Development: Completed, Upstreaming: TBD

Overall status

• Total 43 projects (04-04-2024, wiki)

Development (04-04-2024)

• TBD - 8 (18.60%)

• ONGOING - 2 (4.65%)

• COMPLETED - 33 (76.75%)

Upstreaming (04-04-2024)

• TBD - 13 (30.23%)

• ONGOING - 10 (23.26%)

• COMPLETED - 20 (46.51%)

• Eclipse Temurin 21 and 22 Available on RISC-V

RISE and Adoptium Collaboration

• Significant advancement in the Java ecosystem: the availability of Eclipse Temurin 21 on RISC-V.

• Adoptium Blog: Eclipse Temurin 21 and 22 Available on RISC-V

• RVI Blog: Java 21 and 22 Now Available on RISC-V: A Collaboration Between RISE and Eclipse Adoptium

• RISE Linkedin Post (Working to create a blog page)

GCC Microcontroller CI Proposal

• RISE Build Farm: GCC Microcontroller Target CI proposal from the RISE DevInfra team.

• Add support for testing microcontroller architectures that don’t support all the g extensions. Some possible extensions to test would be:

•  

  • Rv32imac-ilp32

  • Rv64imac-lp64

  • Rv32imc-ilp32

  • Rv64imc-lp64

  • Rv32imc_zicsr_zifencei-ilp32

  • rv64imc_zicsr_zifencei-lp64

Additional combinations with various bitmanip extensions can also be tested.

Projects need these boards are:

• Java/Adoptium: 15 boards to build and test Java 11, 17, 21, and 22. It runs for 2000 hours/week of building and testing

• Go: 5 boards, used exclusively for CI

• AlmaLinux/RockyLinux: 5 boards each, used to build their distributions on RISC-V

• The boards available on Scaleway are likely small to productize it, but they can allow to bootstrap the process.  

28 Mar 2024 

• Michelle Martineau, The Linux Foundation

• Erich Hanke, AMD

• Ming-Yu Hung (MTK)

• Sunil V L, Ventana

• Mark Zhuang, SpacemIT

• Andrei Warkentin, Intel

• Heinrich Schuchardt, Canonical

• Terje Bergstrom, NVIDIA

• Gordan Markus, Canonical

• Ludovic Henry, Rivos

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akeana

• Jian Zhang, BOSC

• Fei Wu, intel

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Victor Costan, Google

• Alexey Bataev, SiFive

• Nathan Egge, Google

• Tim Ouyang, Andes

Agenda

• Welcome New Member: Tenstorrent

• Compilers and Toolchains Deep Dive led by Jeff Law 

• RFP Quick Glance & RP008 update

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Compilers and Toolchains Deep Dive – RP008

• Rivos has identified cases where icounts for spec2017 on RISC-V are at least 10% higher than on AArch64

• Contractor to evaluate those cases for phase 1

• Identify issues driven by ISA differences

• Identify cases where compiler could be doing better along with broad approach to fixing – for phase 2 work

Compilers and Toolchains Deep Dive – GCC Status

• GCC-14 release likely in May

• Initial release with vector support

• Many other code generation improvements, extension support, etc

• Many things already queued up for gcc-15

• Leads to same problem we had last year – a year delay between code going into the tree and the actual release

• Likely resulting in a optimization coordination branch again

• 20 projects identified for 1H2024

• 10 are already at development completion, 8 in progress, 1 under investigation, 1 not started

• 6 already upstreamed (ie, in gcc-14), rest are on hold waiting for development window to reopen

Compilers and Toolchains Deep Dive – LLVM Status

• LLVM 18 release earlier this month

• New cores supported (primarily from SiFive)

• RV32E/RV64E support

• Register pressure sensitive scheduling

• Some TLSDESC support landing, early support for pointer masking

• Arch string ordering constraints relaxed!

• TypePromotion pass enable for RISC-V

• Several extensions moved out of experimental state

• Usual ongoing performance improvements

• Compilers and Toolchains Deep Dive – LLVM Status

• LLVM Projects identified for 1H2024 – only 6, like more that should be added to the page.

• CRC – looks like Joe Faulls (Imagination Technologies) has picked this up from Mikhail.  MR filed and is undergoing review.

• X264 if-conversion.  2 of 3 blockers resolved.  Still hashing through one notable issue in the generic if-conversion code

• Stack Clash – Just getting started, engineer’s 1st LLVM project

• Shrink Wrapping – Just getting started.

• Overly aggressive if-conversion in some cases?

Compilers and Toolchains Deep Dive – MISC

• Should we make LLVM and GCC distinct projects under the RISE umbrella, with Craig or someone else tied into the LLVM community as the leader for the LLVM effort going forward?

• We’ve generally avoided regularly scheduled meetings in this WG per requests from various developers – would a one-a-month “office hours” be useful for RISE members?

21 Mar 2024 

• Michelle Martineau, The Linux Foundation

• Erich Hanke, AMD

• Ming-Yu Hung (MTK)

• Sunil V L, Ventana

• Mark Zhuang, SpacemIT

• Andrei Warkentin, Intel

• Heinrich Schuchardt, Canonical

• Terje Bergstrom, NVIDIA

• Gordan Markus, Canonical

• Ludovic Henry, Rivos

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akeana

• Jian Zhang, BOSC

• Fei Wu, intel

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Victor Costan, Google

• Alexey Bataev, SiFive

• Nathan Egge, Google

• Tim Ouyang, Andes

Agenda

• Firmware Deep Dive led by Sunil V L

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Firmware Deep Dive led by Sunil V L

• 2024 Project Status update

Upstreaming complete.

• PoC available from Andes

• Andes hosting and maintaining github

• Dependency on RVI specs (MPXY/RPMI) to upstream.

• More work required to enable features

• AIA, Smmtt etc

• PoC available.

Dependency on frozen spec to upstream.

• SBI_00_04 - Domain Context Switch Support

• OPTEE_00_01 - OP-TEE support

• SBI_00_05 - OpenSBI RPMI MM Support

• EDK2_00_15 - StandaloneMmPkg RPMI MM support

• 2024 Project Status update Cont.

• Upstreaming complete.

PoC available from Andes

• Andes hosting and maintaining github

• Dependency on RVI specs (MPXY/RPMI) to upstream.

• More work required to enable features

• AIA, Smmtt etc

• PoC available.

Dependency on frozen spec to upstream.

• SBI_00_04 - Domain Context Switch Support

• OPTEE_00_01 - OP-TEE support

• SBI_00_05 - OpenSBI RPMI MM Support

• EDK2_00_15 - StandaloneMmPkg RPMI MM support

2024 Project Status update Cont.

• Helps vendors to support ACPI easily.

• RFC patches sent.

• Major refactoring of DynamicTablesPkg required to support other architectures.

• Maintainers started new staging branch to refactor.

• Upstreaming RISC-V support - probably late 2024 or 2025.

• In progress.

Dependency on UPL specification

• First version of the patch series sent

• EDK2_00_14 - DynamicTablesPkg support

• EDK2_00_10 - UefiPayloadPkg For RISC-V

• EDK2_00_18 - RISC-V QEMU Server Reference Platform

2024 Project Status update Cont.

• Showcased this RISE effort in UEFI DevCon & Plugfest

• https://www.youtube.com/watch?v=2w9iQE8jA1w

• PoC available at https://github.com/intel/FdtBusPkg

• https://www.youtube.com/watch?v=9RqKq4wGYZI

• EDK2_00_03 - FdtBusDxe support

Opens/Challenges

• Significant organization overhead to maintain in member’s github.

• There may not be any upstream repo at all. 

• Ex: MultiArchUefiPkg.

• Getting requests from members for RISE github

• Need TSC help to clearly document the RISE policy for github repo.

14 Mar 2024 

• Evan Harrison, The Linux Foundation

• Andrew de los reyes (Adlr), Rivos

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• Daniel Barboza, Ventana

• Erich Hanke, AMD

• Jeff Law, Ventana

• Jian ZHANG, Beijing Institute of Open Source Chip 

• Kumar Sankaran, Ventana

• Mason Li, MediaTek

• Nathan Egge, Google

• Paul Walmsley, SiFive

• Terje Bergstrom Nvidia

• Tim Ouyang, Andes

• Victor Costan, Google

Agenda

• Reminder: No deep dive for this week

• RFP Status Update

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

• RFP contract Progress

• Contract vendors send Tech Leads & RFP Reporting mailing Biweekly reports

• Please request this cadence when you start engaging with your contractor

• Tech Leads provide Monthly updates to TSC (Report)

• Working group updates to the board will include the RFP updates

Working Groups Opens / Challenge

• Not a distro-integration problem, in the RVI profiles discussion, there has been a lot of effort put into the idea of vertical profiles. There hasn't been a lot of discusssions about horizontal profiles. What happens when we get to the place where I have purchased my motherboard and I have to choose between chips from intel, ventana, etc... This is a discussion that needs to happen, there isn't a concrete answer right now.

• The platform spec - there should be one single distro image for all platforms, this is the high level answer currently.

07 Mar 2024 

• MichelleMartineau, The Linux Foundation

• Tomas Evensen, AMD

• Ming-Yu Hung (MTK)

• Anup Patel, Ventana

• Heinrich Schuchardt, Canonical

• Gordan Markus, Canonical

• Ludovic Henry, Rivos

• Daniel Barboza, Ventana

• Simon Harvey, Imagination

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akeana

• Jian Xiong, Alibaba

• Fei Wu, intel

• Kumar Sankaran, Ventana

• Paul Walmsley, SiFive

• Victor Costan, Google

• Nathan Egge, Google

• Tim Ouyang, Andes

• Andrew de los reyes (Adlr), Rivos

• Jeff Law

• Ruinland, Andes 

Agenda

• New Member Application in Progress- Bytedance

• Distro and Integration Deep Dive- Brian (RedBeard) Harrington

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Distro and Integration Deep Dive- Brian (RedBeard) Harrington

Charter:

• Work is focused on two kinds of projects.

• The champion identifies the directions/projects

• The WG works to prioritize, unravel dependencies on other WGs or file projects in other WGs

• Issues common to multiple Linux distros (e.g. bugs/features in common packages)

• Enabling a specific Linux distro, provided the Linux distro has a champion/vendor.

Ongoing work / requests:

• Establish a new kernel + old glibc baseline for use in Python packaging

•  

  • Ludovic (Rivos) has successfully made inroads with contributors to Alma Linux

  • Unfortunately, due to the packaging policies on many RPM derived distros physical systems are needed for distributable packages.

• Establish support for SecureBoot on RISC-V

•  

  • Heinrich (Canonical) created a patch set in 2021 which Red Hat has failed to merge.  Recently Redbeard updated the patch set and has increased the pressure internal to Red Hat to force feedback. 

Upcoming work / requests:

• As chair for the WG I have been approached by a number of individual contributors and community members who are seeking a free/libre/open source FPGA toolchain which can be used in continuous integration systems.  This is related to the prior citation about the need for physical systems. 

• I have encouraged those reaching out to engage both the relevant mailing lists as well as attend the WG meeting so that I am not a critical mutex on all discussions.

Challenges:

• As with other groups, problems with attendees getting access to the mailing list and calendar invites.

WG Opens 

• Ensuring WG leads have administrator access to their WG mailing lists

29 Feb 2024 

• Evan Harrison, The Linux Foundation

• Erich Hanke, AMD

• Daniel Barboza, Ventana

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akeana

• Paul Walmsley, SiFive

• Terje Bergstrom, Nvidia

• Victor Costan, Google

• Sunil VL, Ventana

• Nathan Egge, Google

• Tim Ouyang, Andes

• Andrew de los reyes (Adlr), Rivos

• Jeff Law

Agenda

• System Libraries Deep Dive led by Nathan Egge

• GCC SPEC analysis work

• RFP Updates

• WG Opens 

• Future topics: AIs from this week

• AIs from last week

System Libraries Deep Dive 2024-February-29

• Toolchain performance plan?

  • Can be fixed quickly by RISE member company

  • Otherwise, can add to RFP for toolchain wor

•  

  • Assign owner for each gap

  • Quickly triage problem

  • Identify fixes into two categories:

  • How anyone run these by Greg? - Paul

  • Jeff to triage these issues that him and his team runs into. Adlr will assist with this effort after Jeff has triaged.

GCC compiler gaps

• GCC riscv64 vs GCC aarch64-SVE

• GCC riscv64 vs LLVM riscv64

•  

  • Note: Some LLVM tests don’t run

• ImageMagick was -30%, but fixed with Zfa

LLVM compiler gaps

• riscv64 LLVM vs riscv64 GCC

• Note: some LLVM tests didn’t run

• Generally see scalar code is behind

22 Feb 2024 

• Michelle Martineau, The Linux Foundation

• Heinrich Schuchatdt, Canonical

• Erich Hanke, AMD

• Daniel Barboza, Ventana

• Barna Ibrahim, Rivos

• Mark Zhuang, Smacemit

• Brian 'redbeard' Harrington, Redhat

• David Weaver, Akeana

• Paul Walmsley, SiFive

• Terje Bergstrom, Nvidia

• Victor Costan, Google

• Gordan Markus, Canonical

• Fei Wu, Intel

• MyungJoo Ham, Samsung

• Sunil VL, Ventana

• Kumar Sankaran, Ventana

• Steve Wanless, Redhat

• Robin Randhawa, SiFive

• Anup Patel, Ventana

• Nathan Egge, Google

• Andrei Warkentin, Intel

• Simon Harvey, Imagination

• Ludovic Henry, Rivos

• Tim Ouyang, Andes

Agenda

• Language Runtimes Deep Dive led by Ludovic Henry

• RFP -  Process; Status Update

• Requiring RVWMO minimum target for development projects

• Xen interest?

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Language Runtimes Deep Dive led by Ludovic Henry

• Optimization Guide is Live!

•  

  • https://gitlab.com/riseproject/riscv-optimization-guide

  • Please contribute!

Next steps

• Get better address than

• https://riscv-optimization-guide-riseproject-c94355ae3e6872252baa952524.gitlab.io/

•  

  • Working with Michelle on that

• RFP: Go Runtime

•  

  • Contract is still in process of being signed

• Ongoing contributions:

•  

  • Assembler and compiler

  • Rotation, atomics, intrinsics, and more

  • Support for Bitmanip

• Compiler optimizations

•  

  • Board farm

  • Need for Adoptium, Go Runtime, AlmaLinux/RockyLinux (for Python)

  • LicheePi/VF2 enough for some workloads, not enough for others

  • Eager to see MILK-V Oasis in action

  • In discussions with AlmaLinux and RockyLinux to understand what they would need (sizing, access)

  • Need to sync up with Distribution WG

• Python packaging

  • It’s being done internally at Rivos for nowWill push to RISE in the coming weeksAll based on GitLab

•  

  • We need to package and distribute Python packages

  • Upstream projects can’t package on RISC-V today

  • Limitation of Python packaging tools

  • We have a WIP to get it based on Ubuntu 22.04

• Java 11 backport

•  

  • Landed yesterday with openjdk/riscv-port-jdk11u:309291f1

  • Going to setup Adoptium CI for that

  • Goal is to get it packaged and tested on public CI by end of month

• Java 17, 21 release

•  

  • Adoptium is very eager to get it done

  • Approved by PMC and Steering Comittee

  • Stuck on having HW for running TCK

  • VF2 board on a desk is not an option at the moment…Working with Eclipse Foundation to make sure they have the resources and know-how to set it upBoard farm would be ideal here; Need for 7-10 LicheePi/VF2 for public + TCK CI

  • Order of priority: 21, 17, 11

V8 & Android

• ISCAS has done the work to port V8 to Android RISC-V

• https://chromium-review.googlesource.com/c/v8/v8/+/5309945 - Approved and merged

• Next: android_toolchain NDK to support RISCV64

• Talking to Nathan about that

15 Feb 2024 

• Evan Harrison, The Linux Foundation

• Erich Hanke, AMD

• Heinrich Schuchatdt, Canonical

• Brian 'redbeard' Harrington, Redhat

• Daniel Barboza, Ventana

• David Weaver, Akeana

• Paul Walmsley, SiFive

• Terje Bergstrom, Nvidia

• Victor Costan, Google

• Kumar Sankaran, Ventana

• Steve Wanless, Redhat

• Andrew de los Reyes (Adlr), Rivos

• Jeff Law, Ventana

• Jeffrey Osier-Mixon (Jefro), Red Hat

• Mason Li, MediaTek

• Nathan Egge, Google

• Tim Ouyang, Andes

• Trilok Soni, Qualcomm

Agenda

• Developer Infrastructure Deep Dive led by Paul Walmsley 

• Association Collaborations - how to organize and discuss

• Adoptium, AGL, Yocto, ?

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Developer Infrastructure WG Introduction & Vision

• Build Farm

• 2023Q4 Review

• 2024Q1 Midpoint Update

• Next Steps

• Board Farm

• Developer Tools

• Challenges

Developer Infrastructure WG Introduction

Charter

• The Developer Infrastructure WG focuses on software and services to support open-source RISC-V developers - both RISE members and the broader open-source community.

Co-chairs

• Barna Ibrahim (Rivos)

• Paul Walmsley (SiFive)

• TSC Contact

• Nathan Egge (Google)

Developer Infrastructure WG Vision

• Three mutually-supporting projects

•  

  • RISE Build Farm (Active)

  • RISE Board Farm (In planning)

  • RISE Developer Tooling (In planning)

• Integration of set of software and user space tools that are necessary to cross build or test.

Goal

• Provide robust development infrastructure and tools to RISC-V developers

RISE Build Farm: Introduction

Objective

• Cross-build and test (in simulation) RISC-V ports of key open source software

• Running in Google Cloud

Status

• Build Farm growing quickly…

• Four active projects spanning three RISE work groups

• 100% growth from 2023Q3

• … but need to grow faster!

Build Farm: 2023Q4 Review

• Broadened the administration base

• Björn Töpel (Rivos) now helping out with general admin tasks

• Two existing projects from 2023Q3 still running

• Linux kernel and gcc post-commit CI 

• Two new projects added in December 2023

• Patrick O’Neill & Edwin Lu (Rivos)

• Ludovic Henry (Rivos)

gcc pre-commit CI

OpenJDK post-commit CI 

Improved policies and administration documentation

• Example: Project Proposal Form

Build Farm: 2024Q1 Midpoint Update (1 of 2)

• Kernel CI instances converted to use GKE - Björn Töpel (Rivos)

• Dealing with technical issues (to be discussed with Google)

• Costly, but well-integrated with Github Runners and offers easier scaling

• Still experimental and under review

Kernel CI doing more work

• New projects in progress

• Patrick O’Neill & Edwin Lu (Rivos)

• GCC/LLVM toolchain fuzzing

Build Farm: 2024Q1 Midpoint Update (2 of 2)

• Broadening the administration base

• Brian “redbeard” Harrington (Red Hat) has expressed interest in helping

• Instance power control now available

• Should reduce spend for intermittent workloads (e.g. OpenJDK CI)

• Discussions in progress with LF IT on support options

• GKE support questions

• Build farm management assistance 

Build Farm Next Steps for rest of 2024Q1

• Add more Build Farm projects 

• Attend other WG meetings to solicit other projects

•  

  • Continue to improve operations

  • Continue improving policies & procedures

  • Continue improving documentation (wiki & internal)

  • Continue investigating external IT assistance

  • Continue recruiting more Build Farm Leads

• Enable webhook-driven builds

• Start tracking our admin service metrics

• Get cloud credit details from LF IT/Google Cloud

• Drive greater efficiency

• Review GKE value

• Implement power control on lightly-used instances

• Investigate spot instances

RISE Board Farm: Introduction

Objective

• Many use cases: OpenJDK, Linux distributions, kernel, Go(?) …

• Provide a range of Linux-capable RISC-V boards to run functionality and performance tests on CI-generated code

• Investigate future feasibility of providing developer access to boards

• Curtis Galloway (Google) coordinating

• Status: Still very early days

• Discussions underway with RVIA, OSUOSL

RISE Developer Tools: Introduction

Objective

• Ideally combines cross and native development environment and native system software and userspace

• Provide a full Linux system image build, boot, and development environment for use on both simulators (QEMU) and RISC-V hardware

• Discussed options so far: Nathan’s Gentoo build and OpenEmbedded

• No one yet coordinating

Challenges

• Improve administration turnaround time for creating new instances, etc.

• Better administrator attendance at our WG meetings

• Drive more activity on the Board Farm and Developer Tools projects

• Looking for help to drive the Developer Tools effort forward

• Need more build projects and project owners!

• Please help

Credits

• Barna Ibrahim (Rivos): Co-chair

• Björn Töpel (Rivos): Kernel CI Build Farm Project Admin, Build Farm Lead, Build Farm Administrator

• Curtis Galloway (Google): Board Farm Lead

• Edwin Lu (Rivos): Toolchain Build Farm Project Admin

• Ludovic Henry (Rivos): Language Runtimes Build Farm Project Admin

• Patrick O’Neill (Rivos): Toolchain Build Farm Project Admin

• Paul Walmsley (SiFive): Co-chair

Language Runtime WG Adoptium Membership Proposal

• Adoptium Introduction

• Only fully Open Source Java vendor - Alignment with RISE Goals

• OSS test suite used by Ubuntu and Redhat JDK

• RISE Adoptium Sponsorship Benefits

• Deeper engagement and visibility with Java Community

• Adoptium is one of the most used Java distribution

• Provide machines to Adoptium (Build farm, Board farm)

Association Collaborations

• Adoptium Introduction

• Only fully Open Source Java vendor - Alignment with RISE Goals

• OSS test suite used by Ubuntu and Redhat JDK

• Board approved supporting via CI services and perhaps get RISE logo listed

• Discussions around Adoptium, AGL, Yocto

How should we propose and track these?

• Any RISE spend should ensure value for money

• ACTION: Discuss with Yocto if they want to become a member: Jefro is happy to support the discussion with Yocto

08 Feb 2024 

• Gordan Markus, Canonical

• Michelle Martineau, The Linux Foundation

• Erich Hanke, AMD

• Heinrich Schuchatdt, Canonical

• Tomas Evensen, AMD

• Jian Xiong, Alibaba

• Barna Ibrahim, Rivos

• Fei Wu, Intel

• Brian 'redbeard' Harrington, Redhat

• Daniel Barboza, Ventana

• David Weaver, Akeana

• Paul Walmsley, SiFive

• Terje Bergstrom, Nvidia

• Simon Harvey, Imagination

• Robin Randhawa,SiFive

• Mark Zhuang, SpacemIT

• Ludovic Henry, Rivos

• Victor Costan, Google

• Kumar Sankaran, Ventana

• Steve Wanless, Redhat

• Anup Patel, Ventana

Agenda

• Simulator Emulator Deep Dive led by Daniel Barboza

• Debug & Profiling Deep Dive Led By Fei Wu 

• RISC-V Optimization Guide Publication

• RFP:  RP004 Review and Status

• WG Opens/challenges

• Firmware: OP-TEE WG Opens 

• AIs from last week

Simulator Emulator Deep Dive led by Daniel Barboza

• WG 2023 wrap-up

• WG 2024 item status

• Projects not yet started

• Projects in progress, not yet sent for review

• Projects under review

2023 wrap-up:

• SE_01_001 - QEMU linux-user riscv_hwprobe syscall support

• SE_01_002 - QEMU Virtual IRQ and IRQ filtering support

• SE_01_014 - QEMU query-cpu-model-expansion API

• SE_02_001 - QEMU Vector crypto support

• SE_01_009 - QEMU ACPI support for AIA

• SE_01_010 - QEMU ACPI support for PLIC

• SE_01_011 - QEMU RVA22 profiles support

• SE_01_005 - QEMU PCIe passthru on x86 host

• Projects completed and available in QEMU 8.0 (launched Dec 2023):

• Projects completed and available in QEMU 9.0 (to be released April 2024):

• Projects not completed in time and pushed to 2024:

2024 projects - not yet started

• Tracker project

• Project RP005 Add QEMU TCG support for V and Zvk

• Bidding ends Feb 2nd

• RISE contacts: Max Chou (Si-Five) and Daniel Barboza (Ventana)

• SE_01_003 - QEMU WorldGuard support

• SE_01_016 - QEMU linux-user hwprobe kernel parity

• SE_01_021 - QEMU RVA23 profile support

• SE_02_004 - QEMU RVV performance enhancements

2024 projects - in progress, not sent for review

• Community project (Starfive)

• Community project (Starfive)

• SE_01_017 - QEMU ACPI SPCR support for RISC-V

• SE_01_018 - QEMU ACPI PPTT support for RISC-V

• SE_01_019 - QEMU ACPI SRAT/SLIT(NUMA) support for RISC-V

• SE_01_020 - QEMU SMBIOS support for RISC-V

2024 projects - upstream progress ongoing

• Last version:  v1

• Project has dependencies on UBOOT and GRUB

• Last version:  v5

• Last version: v1

• Development done by Rivos, Ventana will help with the upstreaming

• SE_01_005 - QEMU PCIe passthru on x86 hosts

• SE_01_004 - QEMU IOPMP support

• SE_01_015 - QEMU RISC-V IOMMU support

Debug & Profiling Deep Dive Led By Fei Wu 

2023 projects

• Code ready for running integer part of RVV instructions, but in slow review process

• v7 patch submitted, hoping get pushed soon

• Technical ready, but rv32 on llvm is inactive, not only asan

• DP_04_001 - Userspace Cycle/Instret access (Done)

• DP_01_002 - Evaluate GDB status on RISC-V (Done)

• DP_02_002 - Evaluate LLDB status on RISC-V (Done)

• DP_00_001 - Valgrind vector support

• DP_01_003 - GDB Simulator - Add Zc support

• DP_05_001 - Address Sanitizer

2024H1 new projects

• DP_04_002 - Perf event discovery/encoding from json file (Dev Done)

• DP_04_003 - Perf CTR (equivalent of x86 LBR) support (Dev Done)

• DP_04_004 - Perf CTR call stack mode support (WIP)

• DP_07_003 - DynamoRIO drcachesim & drcov support (WIP)

• DP_07_004 - DynamoRIO V extension support

• DP_07_005 - DynamoRIO enable remaining tests that are also supported by AArch64

• DP_07_006 - DynamoRIO RISC-V specific documentation

Software performance regression CI Infrastructure (Discussion)

• Currently, many software optimizations on RISC-V are performed on QEMU or non-representative hardware with limited resources. These optimizations are based on the developer's interpretation of the features, which may not align with the actual hardware or may vary across different hardware.

• Software performance regressions are a common occurrence and it's crucial that we identify and fix them at the earliest possible stage.

• Problem to solve

• Linaro extends LKFT (Linaro Kernel Functional Test) functionalities to include automatic detection and reporting of performance regressions in 2021

• Test on real hardware and focus on key software, easy to scale to other software

• RFP?

RISC-V Optimization Guide Publication

• TSC Optimization Guide discussion; Agreement on dropping the vendor languages for the release - Merged.

• This is a living document and will continued to be updated 

• Publish the Optimization Guide 02/09/2024

• Follow up with RVI leadership on the published link. 

Firmware: OP-TEE WG Opens 

Rationale

Risk of fragmentation

• Multiple orgs are already working on OP-TEE ports to RV64

• 5 known so far, probably more exist

• The fragmentation scope is likely to increase over time

• Especially as ‘new’ security architecture features gain traction

• Eg WorldGuard, SMMTT et al

Technical challenges

• OP-TEE presents some technical challenges for RISC-V

• These need structured debate, design and development

• Eg OP-TEE’s pre-emption model is tricky for RISC-V

• OP-TEE will probably have M-Mode dependencies

Strategic issues

• Upstream OP-TEE does not have a RISC-V maintainer

• OP-TEE is fundamentally an Arm led initiative

• A fragmented upstreaming effort will benefit no one

Logistical challenges

• A public platform is needed

• That supports relevant security features

• Qemu virt is a natural default option

• But similar risks apply here as well

• Alignment needed on the nature of qemu support

• Such alignment needs a RISC-V specific forum

RISE as a convergence point will mitigate these problems

Collaboration model outline

• Key elements

•  

  • An OP-TEE focus group within the Firmware WG

  • A public OP-TEE staging repository within RISE

  • A RISE hosted OP-TEE specific blog (or similar)

• Workflow

•  

  • Work definition and delegation

  • The focus group collaborates on work definition, delegation

  • Establishing dependencies on other WGs or projects, if any

  • Outputs are published externally on the blog

  • Promotes wider community awareness

  • Reduces the potential for any redundant work etc

• Code contribution

•  

  • Code contributions are ‘collected’ in the staging repository

  • From both RISE members and non-members

  • The focus group resolves any ‘impedance mismatches’

  • Between work in this repository, the OP-TEE upstream, etc

• Upstream pull requests

•  

  • Code contributions are suitably reviewed and processed

  • Upstream PRs are raised by relevant work owners

  • Upstream review

  • The focus group helps resolve upstream queries etc

  • Through to upstream inclusion of code

OP-TEE focus group

• Is there precedent for such a thing ?

• Why can’t we just engage directly with upstream instead ?

• What is the structure of such a focus group ?

• What is the impact on other FW WG work ?

OP-TEE staging public code repository

• Is there precedent for such a thing ?

• We don’t want to create another upstream

• Such a repository needs ownership and maintenance

• Also a branching regime etc

OP-TEE public blog

• Is there precedent for such a thing ?

• This needs ownership and maintenance

• Info on this blog needs to be ‘well formed’ - needs thought

Miscellaneous

• The existing OP-TEE RFP may be used to kickstart work

• Nuclei’s publicly available work can help too

01 Feb 2024 

• Jeff Law, Ventana

• Evan Harrison, The Linux Foundation

• Erich Hanke, AMD

• Tomas Evensen, AMD

• Barna Ibrahim, Rivos

• Larry Wikelius, Qualcomm

• Brian 'redbeard' Harrington, Redhat

• Daniel Barboza, Ventana

• David Weaver, Akeana

• Paul Walmsley, SiFive

• Terje Bergstrom, Nvidia

• Jian Zhang, BOSC

• Ludovic Henry, Rivos

• Victor Costan, Google

• Adlr (Andrew de los Reyes), Rivos

• Jefro (Jeffrey Osier-Mixon), Redhat

• Kumar Sankaran, Ventana

• Mason Li, Mediatek

• Steve Wanless, Redha

Agenda

• Board Representative Larry Wikelius (Qualcomm)

• RISE Optimization Guide

• RFP Prioritization Approvals

• WG Opens

• Future topics: WG Opens/challenges

• AIs from last week

25 Jan 2024 

Attendees

• Jeff Law, Ventana

• Michelle Martineau, The Linux Foundation

• Erich Hanke, AMD

• Tomas Evensen, AMD

• Nathan Egge, Google

• Barna Ibrahim, Rivos

• Larry Wikelius, Qualcomm

• Brian 'redbeard' Harrington, Redhat

• Daniel Barboza, Ventana

• David Weaver, Akeana

• Paul Walmsley, SiFive

• Terje Bergstrom, Nvidia

• Simon Harvey, Imagination

• Anup Patel, Ventana

• Heinrich Schuchardt, Canonical

• Jian Xiong, Alibaba

• Jian Zhang, BOSC

• Robin Ranhawa, SiFive

• Ludovic Henry, Rivos

• Ming-Yu hung, MediaTek

• Victor Costan, Google

Agenda

• Board Representative Larry Wikelius (Qualcomm)

• Contractor project payments 

• Kernel and Virtualization Deep Dive led by Anup Patel 

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Kernel and Virtualization Deep Dive led by Anup Patel 

AGENDA:

• RVA23 profile extensions

• Updates on discovery

• Overall status

• 2023-2H

• Updates on projects

• Status on priorities

• Overall status

• 2024-1H

• Final priorities

• Overall status

RVA23 updates on Discovery

• List of RVA23 profile extensions on wiki in-sync with latest spec

• https://lf-rise.atlassian.net/wiki/display/HOME/RVA23+Profile 

• HWPROBE additions (in past 3 months)

• Zicboz, Zfhmin, Zkt, Zvfhmin, Zvbb, Zvkt

• Zvkned, Zvknhb, Zvkb, Zvkt, Zvkg, Zvksed, Zvksh, Zvkb, Zvbc

• Zihintntl, Zicond, Zacas, Zfa, Zfh, Zbc, Zvfh

• KVM ONE_REG additions (in past 3 months)

• Zfhmin, Zkt, Zvfhmin, Zvbb, Zvkt

• Zvkned, Zvknhb, Zvkb, Zvkt, Zvkg, Zvksed, Zvksh, Zvkb, Zvbc

• Zihintntl, Zicond, Zfa, Zfh, Zbc, Zvfh

RVA23 Extensions overall profile status

• Total 83 extensions (25-01-2024, wiki)

• Kernel HWPROBE (25-01-2024)

•  

  • NA - 36 (43.37%)

  • TBD - 16 (19.28%)

  • COMPLETED - 31 (37.35%)

• KVM ONE_REG (25-01-2024)

•  

  • NA - 10 (12.05%)

  • TBD - 27 (32.53%)

  • COMPLETED - 46 (55.42%)

• 2023 2H Project Updates

• LK_01_020 - Vector crypto extensions discovery using HWPROBE

•  

  • Development: Completed, Upstreaming: Completed

• LK_01_033 - Bitmanip extensions discovery using HWPROBE

•  

  • Development: Completed, Upstreaming: Completed

• LK_02_004 - KVM AIA irqbypass

•  

  • Development: Completed, Upstreaming: TBD

• LK_02_019 - KVM vector crypto extensions virtualization

•  

  • Development: Completed, Upstreaming: Completed

Kernel

• STILL NO ACTIVITY from RISE member

• New kernel irqchip maintainer has requested few changes in the AIA DT drivers

AIA ACPI support upstreaming blocked on DT drivers

• Being done along with AIA ACPI support

• STILL NO ACTIVITY from RISE member

Sdtrig spec is frozen but the SBI DBTR spec will be part of SBI v3.0

• Memory Hot(Un)plug

• KASAN support

Basic ACPI support

• AIA support (DT, ACPI)

• PLIC support (ACPI)

• IOMMU (DT)

Vector extension support

• Vector crypto extension discovery using HWPROBE

• Native/hosted debug support (aka HW breakpoints)

• Bitmanip extension discovery using HWPROBE

KVM

• Patches on LKML blocked on AIA DT driver upstreaming

• Work being done in a fork since it depends on AIA DT driver and IOMMU upstreaming

• Sdtrig spec is frozen but the SBI DBTR spec will be part of SBI v3.0

Vector extension virtualization

• AIA irqchip (incl. kvmtool and qemu support)

• AIA IMSIC guest file support

• AIA irq-bypass (aka Device MSI virtualization, incl. kvmtool and qemu)

• KVM vector crypto extension virtualization (incl. kvmtool and qemu)

• KVM Native/hosted debug virtualization

• KVM bitmanip extension virtualization (incl. kvmtool and qemu support)

Overall Status:

• Total 27 projects (25-01-2024, wiki)

• Development (25-01-2024)

• TBD - 2 (7.41%)

• PROTOTYPE - 2 (7.4%)

Native/hosted debug blocked on specifications

• ONGOING - 0 (0%)

• COMPLETED / NOTNEEDED - 23 (85.19%)

• Upstreaming (25-01-2024)

• TBD - 6 (22.22%)

• ONGOING - 7 (25.93%)

• COMPLETED / NOTNEEDED - 14 (51.85%)

2024-1H: Final priorities

Kernel

• HWPROBE discovery for for Z* and S* extensions included in RVA23 profile

• ACPI LPI support

• ACPI CPPC support

• ACPI PPTT support

• ACPI NUMA support

• ACPI SPCR support

Steal time support

• System suspend support

• Debug console support

• PMU snapshot support

• ISA Extensions

• ACPI improvements

• SBI v2.0

KVM

• KVM selftests

• Host nested acceleration (Defined by SBI v2.0)

• ISA extensions

• ONE_REG discovery for Z* and S* extensions included in RVA23 profile

Virtualize SBI v2.0 support

• Steat time support for Guest (incl. KVMTOOL and QEMU-KVM)

• System suspend support for Guest (incl. KVMTOOL and QEMU-KVM)

• Debug console support for Guest (incl. KVMTOOL and QEMU-KVM)

• PMU snapshot support for Guest (incl. KVMTOOL and QEMU-KVM)

Xen

• Shared memory and event channel

• IOMMU driver

2024-1H: Overall status

• Total 43 projects (25-01-2024, wiki)

• Unassigned - 6 (13.95%)

Development (25-01-2024)

• TBD - 13 (30.23%)

• ONGOING - 4 (9.30%)

• COMPLETED - 26 (60.47%)

Upstreaming (25-01-2024)

• TBD - 20 (46.51%)

• ONGOING - 13 (30.23%)

• COMPLETED - 10 (23.26%)

Follow up: Compilers and Toolchains Deep Dive (1/18/24) 

• Effort just starting to evaluate LLVM & GCC against each other to help drive improvements in both

• Initial focus on Spec2017 (int and fp) on rv64gcv+bitmanip

• Dynamic instruction counts rather than uarch/cycle metrics for now

• GCC/LLVM Vector Investigations  Internal to RISE right now

• Goal is help both compilers know where to focus improvement efforts going forward, not to promote one compiler over the other or one design over another

18 Jan 2024 

Attendees

• Jeff Law, Ventana

• Tim Ouyang, Andes

• Evan Harrison, The Linux Foundation

• Erich Hanke, AMD

• Tomas Evensen, AMD

• Nathan Egge, Google

• Barna Ibrahim, Rivos

• Gorden Markus, Canonical

• Brian 'redbeard' Harrington, Redhat

• Daniel Barboza, Ventana

• David Weaver, Akeana

• Paul Walmsley, SiFive

• Terje Bergstrom, Nvidia

• Victor Costan, Google

Agenda

• Compilers and Toolchains Deep Dive led by Jeff Law

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Compilers and Toolchains Deep Dive

• Effort just starting to evaluate LLVM & GCC against each other to help drive improvements in both

• Initial focus on Spec2017 (int and fp) on rv64gcv

• Dynamic instruction counts rather than uarch/cycle metrics for now

• Goal is help both compilers know where to focus improvement efforts going forward, not to promote one compiler over the other or one design over another

Compilers and Toolchains Deep Dive – GCC

CRC optimization

• Detect and optimize CRC loop to table lookup or clmul

• 10-20% on Coremark depending on clmul/memory latency

• Works on more than just Coremark

• Implementation done.  Upstreaming effort to start shortly

• Autovectorization focus expanding to include specfp

• Wrf (70%), roms (35%), cam4 (17%), fotonik (12%), bwaves (5%), cactuBSSN (5%) parest (5%)

• Initial evaluation starting with instruction counts

• Expecting to see results similar to x86_64 and aarch64

• Additional mem* and str* vector optimizations

• Inline expansion when source/destination may overlap

• glibc ifunc based implementations of key routines as well

Compilers and Toolchains Deep Dive – GCC

Other FP optimizations

• Use rsqrt estimator to improve key (unvectorizable) loop in nab  - not 100% sure it’s profitable, will need testing

• Use dual fmacs and recip estimator to improve atan2 which is heavily used by WRF benchmark

• Increase lookahead in scheduler – becomes more important as we start seeing dual FPU designs

• Stack Clash Mitigations

• Naive implementation limping along already

• Good implementation (reduce explicit probing) underway

• Closest to AArch64 implementation, needs PSABI verbage

Compilers and Toolchains Deep Dive – LLVM

• Big thanks to Craig Topper (SiFive) for covering LLVM

• Split register allocator, vector first, then scalar registers

• Allows for vsetvl insertion between phases so vector registers can be partially spilled

• Stop considering conditional branches as “expensive”

• Prefers multiple branches over logicals to combine several branches into one

• LTO vs -march/-mcpu issues in crosshairs

• Core-V support (xcvmem, xcvelw)

• Intrinsic and assembler support for various new extensions

• Global Dynamic TLSDESC

• ULEB128 relocation support for DWARF V5 & C++ exceptions

• Vector calling conventions merged.  Proposal for passing fixed length vectors in vector registers under review

• The RFP is in the pipeline right now and should close in February. This could also start as a Compiler email thread, and if needed this can be further discussion inside the Compiler's meeting.

Dev Infra: Board Farm Update

• RISC-V International Effort overview

• Dev Boards program enabling developers with hardware.  

• Labs Cloud Access - CI enablement; No common interfaces, or common operational standards (yet).

Considerations for next steps are 

• RISE can propose/sponsor a Program and leverage the existing RVI infrastructure to enable hardware with developers.  

• Longer Term: How best to enable CI jobs that require RISC-V Hardware. Utilize labs such as OSU-Open Source lab etc. 

11 Jan 2024 

• Anup Patel, Ventana

• Barna Ibrahim, Rivos

• Brian 'redbeard' Harrington

• Daniel Barboza, Ventana

• David Weaver, Akeana

• Evan Harrison, Linux Foundation

• Fei Wu, Intel

• Heinrich Schuchardt, Canonical

• Jian Zhang, BOSC

• Ludovic Henry, Rivos

• Ming Yu-Hung, Mediatek

• Nathan Egge, Google

• Paul Walmsley, SiFive

• Ruinland Tsai,

• Simon Harvey, Imagination

• Sunil L, Ventana

• Tim Ouyan, Andes

• Tomas Evensen, AMD

• Victor Costan, Google

Agenda

• Firmware Deep Dive led by Sunil V L

• Optimization Guide Status

• WG Opens 

• Future topics: WG Opens/challenges

• AIs from last week

Firmware Deep Dive

New projects added.

• 2H 2023 Project Status

• 1H 2024 Projects (Draft)

• Discussion Topics

FW WG - New projects added

• EDK2

• EDK2_00_18 - RISC-V QEMU Server Reference Platform - 1H 2024

• COREBOOT

• COREBOOT_00_01 - coreboot for SiFive Unmatched - 1H 2024?

• COREBOOT_00_02 - coreboot for StarFive VisionFive2 - 1H 2024?

• COREBOOT_00_03 - LinuxBoot for coreboot on RISC-V - 2H 2024

• COREBOOT_00_04 - TianoCore for coreboot on RISC-V - 2H 2024

• HPC (?)

• HPC_00_01 - Minimal functional SBI definition for HPC (placeholder)

• OP-TEE

• OPTEE_00_01 - OP-TEE support for RISC-V - 2H 2024

FW WG - 2H 2023 - Projects Status

FW WG - 1H 2024 - Projects (DRAFT)

FW WG - Discussion Topics

• Projects discovering spec gaps. Spec freeze may take time.

• Large projects are difficult to break down initially and then can spill over into next half.

• Projects being done by non-RISE members. How to update wiki page?

• RISE specific gitlab/github.

RISC-V Optimization Guide Discussion

• Leads Ludovic and Simon

• Licencing The various RVI specs are distributed under the CC-BY-SA-4.0 license (Ex. RISC-V ISA Manual ).

• Moved to Git invite only within RISE team members. 

Time lines: 

• 11/06/2023 - 01/15/2023 Seeking feedback from RISE 

• 01/15/2023 Inform RVI and give access to the document. 

• Week of Jan 31st, 2024 

• Open up to RISC-V ecosystem - public, git repo, PDF/website/other

• Publish on RISE Social Media

• How many people can we add to the repo, question for Michelle

• Adjust the timelines until people can get access to gitlab

• Is it possible to get accss to the repo before, Michelle has sent information for DCMA to github. Nathan has to look into this information.

• When we get more contributors, Ludovic will send out an email and this will kickoff the two weeks date for feedback from RISE.

14 Dec 2023 

Attendees:

• David Weaver, Akeana

• Nathan Egg, Google 

• Victor Costan, Andes

• Barna Ibrahim, Rivos

• Tim Ouyang, Andes 

• Kumar Sankaran, Ventana 

• Daniel Barboza, Ventana 

• Brian (Redbeard) Harrington, Red Hat 

• Terje Bergstrom, NVIDIA 

• Evan Harrison, The Linux Foundation

• Jeff Law, Ventana

• Erich Hanke, Canonical

• Tomas Evensen, AMD

• Ammone Chapackdee, Ventana

• Andrew de los reyes (Adlr), Rivos

• Ludovic Henry, Rivos

• Trilok Soni, ISCAS

Agend

• RISC-V Optimization Guide

• Valgrind RISC-V Porting discussion follow up  

• WG Opens 

• LLVM CI RFP Status

• Future topics: WG Opens/challenges

• AIs from last week

• 2FTE Reporting Best Practices

• Meeting on January 4th

RISC-V Optimization Guide Discussion

• Leads Ludovic and Simone

• Added Intended Audience and Vendor Neutrality language

• Licencing The various RVI specs are distributed under the CC-BY-SA-4.0 license (Ex. RISC-V ISA Manual ).

• What is the specific use case for this? The question from the team is, who is this directed towards?

• The team has decided to continue work on this document before it is published.

• ACTION:

•  

  • Decision: Move to Gitlab only with RISE team members

Time lines: 

• 11/06/2023 - 12/15/2023 Seeking feedback from RISE 

• 12/15/2023 Inform RVI and give access to the document. Can we resolve the comments inputs?  

• We pushing this back to the week of 1/8/24

• ACTION: Check in with team after the holidays to see if they are ready to present to RVI

• Week of Jan 8th, 2024 

• Open up to RISC-V ecosystem - public, git repo, PDF/website/other

• Publish on RISE Social Media

Debug & Profiling: Valgrind Porting to RISC-V

• No RISC-V support on Valgrind

• Valgrind ownership? 

• Valgrind-riscv64; poc-rvv

• There needs to be a further discussion on this topic: Barna and Jeff will take this offline to further schedule. To be picked up in Jan.

 Working Group Opens

• Python Packaging Challenge

•  

  • TL;DR: building python packages depends on AlmaLinux 8 which doesn’t support RISC-V

  • The two, non-exclusive, and complementing proposals are:

  • GCC Auto Vectorization

  • Autovec in GCC is new and there is a need to push to improve codegen.

  • Other architectures have honed autovec with years of work and dozens of engineers working. This is one step in evening the field.

  • Have RISE to explore what it takes and then determine next steps.

07 Dec 2023 

Attendees:

• David Weaver, Akeana

• Nathan Egg, Google 

• Victor Costan, Andes

• Barna Ibrahim, Rivos 

• Fei Wu, Intel 

• Tim Ouyang, Andes 

• Kumar Sankaran, Ventana 

• Daniel Barboza, Ventana 

• Brian (Redbeard) Harrington, Red Hat 

• Terje Bergstrom, NVIDIA 

• Paul Walmsley, SiFive 

• Robin Randhawa, SiFive

• Michelle Martineau, The Linux Foundation

• Jeff Law, Ventana

• Anup Patel, Ventana

• Erich Hanke, Canonical

• Jian Xiong, Alibaba

• Ken Unger, Microchip

• MyungJoo Ham, Samsung

• Ming-Yu Hung, MediaTek

• Simon Harvey, Imagination

• Tomas Evensen, AMD

• Gordan Markus, Canonical

Agenda

• System Libraries Deep Dive Q&A  (Nathan) (10mins)

• Distro Integration Deep Dive

• Debug & Profiling Projects 2024 (Ammone/Fei) (10 mins)

• RISC-V Optimization Guide Discussion and Inputs (10 mins)

• RFP LLVM CI Announcement Draft

• AIs from last week

• WG Updates/Challenges & Future Topics

System Libraries Deep Dive Q&A  (Nathan) (10mins)

Guide for Optimizing RISC-V Assembly

• RISC-V Optimization Guide [1]

•  

  • Document started by Rivos, now with many contributors from other companies

  • Key idea: Best practices guide with recommendations for assembly optimizations

• Target application processors

•  

  • smartphone, laptop, desktop, server; OoO; rv64gv*

  • Example code illustrative of how “strip mining” routines should be written

• Want everyone’s input. It should be vendor-agnostic.

•  

  • It’s about optimizing RISC-V software, similar to Intel and ARM guides

• Moving to GitLab project so we can take contributions from outside

•  

  • Text diffs, PDF generation, discoverable, etc.

[1] https://docs.google.com/document/d/1dp6JtXIE3ucCl71_Vr711tX24Kd3JSS2x0Y3urh8k1U

Case Study: Adding RVV 1.0 to dav1d [1]

• dav1d is an AV1 decoder

•  

  • Goals: fastest software decoder, cross-platform, small binary size

• Achieves this through a *LOT* of handwritten assembly!

Totals grouped by language (dominant language first):

asm:         208824 (84.23%)

ansic:        38956 (15.71%)

sh:             153 (0.06%)

• Essentially a C orchestrator around specialized DSP functions

•  

  • C ABI conformance matters, assembly functions can do weird things

• Good place to test RISC-V Vector assembly routines

•  

  • Excellent testing framework with performance evaluation built-in

[1] https://code.videolan.org/videolan/dav1d/-/merge_requests/1463

dav1d Correctness Testing

• Unit tests:

• Driven by checkasm test harness

  • For each DSP function

  •  

    • Generate random input data with padding

    • Call C function

    • Call ASM function        <-- more on this later

    • Compare output data

    • Check padding not overwritten

•  

  • For each CPU configuration (e.g., SSE2, SSSE3, SSE4.1, AVX2, AVX-512)

• Integration tests:

  • Decode 772 test videos and compare md5sum

  • Run previously found configurations from fuzzing bugs

•  

  • Driven by dav1d command line decoder

Adding RISC-V Vector Specific Functions

• Implemented a single DSP function for 2D 4x4 transform

•  

  • Used HWCAP for feature detection, showed how to integrate code at runtime

  • Hand-written RVV 1.0 assembly, ~200 instructions

• Added C code for new architecture, RISC-V

•  

  • Some boiler-plate code, but good example for other projects to follow

  • Hooks into existing testing infrastructure

• This is enough to test DSP function for correctness

Updating checkasm for RISC-V C ABI

• Want to ensure ASM functions don’t have side effects

•  

  • Check that callee-saved registers s0 to s11 and fs0 to fs11 are preserved

  • Check that unallocatable registers gp and tp are preserved

  • Check that the call frame registers ra and sp are preserved

• Prevent dependencies on uninitialized values

•  

  • Load callee-saved registers s0 to s11 and fs0 to fs11 with random values

  • Load temporary registers t0 to s6 and ft0 to ft11 with random values

  • Fill stack space below sp with random values

• Add stack canary above last parameter to detect stack smashing

dav1d Performance Testing

• Built-in performance measurement tool

  • Run C code in a loop N times

  • Run ASM code in a loop N times

  • Compute speed-up

•  

  • Driven by checkasm test harness

• Allows for easily repeatable performance measurements

•  

  • Across different RISC-V devices

  • Over-time to ensure no regressions are introduced

  • Potentially compare same functions to *other* ISAs

• Easy to run, just add --bench to previous checkasm command 

• Performance benefit is not clear

•  

  • Still no access to RISC-V Vector 1.0 hardware

  • Under QEMU, emulated RVV running predictability *slower* than scalar!

Testing Multiple Vector Lengths

• In .gitlab-ci.yml

test-debian-riscv64:

extends:

     - .debian-amd64-common

     - .test-common

needs: [ "build-debian-riscv64" ]

script:

     - meson setup build --buildtype release

                         -Dtestdata_tests=true

                         -Dlogging=false

                         -Dtrim_dsp=false

                         --cross-file package/crossfiles/riscv64-linux.meson

     - ninja -C build

     - cd build && time meson test -v --timeout-multiplier 2

parallel:

     matrix:

     - QEMU_CPU: [ "rv64,v=true,vext_spec=v1.0,vlen=128,elen=64",

                   "rv64,v=true,vext_spec=v1.0,vlen=256,elen=64",

                   "rv64,v=true,vext_spec=v1.0,vlen=512,elen=64",

                   "rv64,v=true,vext_spec=v1.0,vlen=1024,elen=64" ]

Compliant RVV 1.0 Hardware Arrives!

• Ported Gentoo VM Developer Environment to K230 hardware

•  

  • Modern developer tooling (clang-17.0.3, gcc-13.2.1, rust-1.73, etc)

  • Images can be made available to anyone with same hardware

[1] https://github.com/kendryte/k230_sdk/issues/37 

Runs 7.4x faster than C on RVV hardware!

Roughly comparable to other architectures

Kendryte K230 “good enough” for testing?

Pros:

• Board contains spec compliant RVV 1.0

• Shows speed-up compared to C code

•  

  • Unblocks upstream projects who want numbers

Cons:

• May not represent RISC-V devices that ship

at volume

• Hard to get access to, currently sold out

Online now! Email ssh key to negge@google.com

RP002 - Optimize H.264 Decoding in FFmpeg

Accelerate H.264 decoding in FFmpeg by adding  RISC-V optimizations. Specifically,

1. Implement specialized RISC-V DSP routines for the identified functions in H.264 DSP functions

2.  

   1. Using hardware feature detection so specialized functions are enabled at runtime

   2. Only ratified extensions to RISC-V can be used, for example V + Zb{a,b,c,s}

   3. Implementations should work on vector lengths 128b and greater

3. Develop a test harness to verify correctness against the pure C implementation

4.  

   1. Randomized input verified against C for each specialized DSP function

   2. Update testing infrastructure to run full correctness test harness (2a) in CI

5. Develop a test harness to measure performance against the pure C implementation

6.  

   1. Unit tests to benchmark specialized DSP functions, see https://code.videolan.org/videolan/dav1d/-/merge_requests/1463

   2. Integration tests that measure H.264 decoding speed for set of real-world videos

7. Produce a performance report based on (3) that compares the pure C to optimized code

8.  

   1. DSP function speed-up on RISC-V hardware v C implementation

   2. Table of video sequence decode speeds (in FPS) before and after optimization

   3. Roughly equivalent data on alternate ISAs (for reference only)

9. Testing shall be done on any conformant RISC-V hardware that contains RVV 1.0 extension, for example:

10.  

    1. Kendryte K230 - https://www.canaan.io/product/k230

11. Software shall be licensed MIT/BSD or similar so it is available to other projects

Low Lights

• QEMU executes RVV optimizations *slower* than scalar code

•  

  • This is a bigger problem than initially expected

  • Impact on developer productivity: slow execution time, drag on emulated systems

  • Gets worse the *more* RVV code you have!

• Needed to disable RVV in bionic under QEMU as mitigation [1]

•  

  • "Android boots 2x faster on qemu if you disable V"

• RP005 - Add QEMU TCG support for V and Zvk   <--  this will help! 

[1] https://android.googlesource.com/platform/bionic/+/refs/heads/main/libc/arch-riscv64/dynamic_function_dispatch.cpp#47 

ILP32 on RV64

• Guo Ren (Alibaba) present slides from Linux Plumbers Conf [1]

•  

  • Idea is to use 32-bit pointers with 64-bit instructions

  • Saves ~25% memory (measured in pages) in the Linux Kernel

  • Requires a separate ABI

• Conclusion from SL WG was this is not a RISE priority

•  

  • High cost to support multiple ISA’s foisted on the OSS and developer ecosystem

  • Long-term burden on compatibility for minimal gain

[1] https://lpc.events/event/17/contributions/1475/ 

Distro Integration Deep Dive

Purpose: To provide direction and feedback around the integration of the software components needed to comprise an entire operating system

Near term goals: Alignment of packages needed for new development (HEAD versions of gcc, qemu, et al)

Long term goals: Establish a communication channel between operating system developers and the groups building foundational components incorporated into operating systems.

• Inaugural meeting held - Dec 5th

• Over 10 attendees

• Reinforced the process of working on the mailing list

• Permissions on documents is a challenge

• e.g. Creating a spreadsheet where users can collaborate requires a lot of manual “Grant access to…” management (if keeping documents within RISE)

• The discussion of compressed instructions has continued in the WG, but the TSC has made it clear this is a decided issue.

Debug and Profiling Projects 2024

RISC-V Optimization Guide Discussion and Inputs (10 mins)

30 Nov 2023 

Attendees:

• Ammone Chapackdee, Rivos 

• Nathan Egg, Google 

• Barna Ibrahim, Rivos 

• Andrei Warkentin, Intel 

• Ludovic Henry Rivos 

• Tim Ouyang, Andes 

• Kumar Sankaran, Ventana 

• Daniel Barboza, Ventana 

• David Weaver, Akeana 

• Brian (Redbeard) Harrington, Red Hat 

• Terje Bergstrom, NVIDIA 

• Paul Walmsley, SiFive 

• Andrew (Adlr), Rivos 

• Heinrich Schuchrdt, Canonical 

• Mason Li, Meditek 

• Trilok Soni, 

• Wei Wu, ISCAS 

• Evan Harrison