[v2,00/19] riscv: report more ISA extensions through hwprobe

Message

Clément Léger Oct. 17, 2023, 1:14 p.m. UTC

In order to be able to gather more information about the supported ISA
extensions from userspace using the hwprobe syscall, add more ISA extensions
report. This series adds the following ISA extensions parsing support:

- Zfh[min]
- Zvfh[min]
- Zihintntl
- Zbc
- Zvbb
- Zvbc
- Zvkb
- Zvkg
- Zvkned
- Zvknh[ab]
- Zvksed
- Zvksh
- Zvkn
- Zvknc
- Zvkng
- Zvks
- Zvksc
- Zvksg
- Zvkt
- Zfa
- Zbkb
- Zbkc
- Zbkx
- Zknd
- Zkne
- Zknh
- Zkr
- Zksed
- Zksh
- Zkt

Some of these extensions are actually shorthands for other "sub"
extensions. This series includes a patch from Conor/Evan that adds a way
to specify such "bundled" extensions. When exposing these bundled
extensions to userspace through hwprobe, only the "sub" extensions are
exposed.

In order to test it, one can use qemu and the small hwprobe utility
provided[1]. Run qemu by specifying additional ISA extensions, for
instance:

$ qemu-system-riscv64 -cpu rv64,v=true,zk=true,zvksh=true,zvkned=true
  <whatever options you want>

Then, run hwprobe_dump:

$ ./hwprobe_dump
Base system ISA:
 - IMA_FD
 - C
 - V
Supported extensions:
 - Zba
 - Zbb
 - Zbs
 - Zbc
 - Zbkb
 - Zbkc
 - Zbkx
 - Zknd
 - Zkne
 - Zknh
 - Zkt
 - Zvkned
 - Zvksh
 - Zihintntl
 - Zfa

Link: https://github.com/clementleger/hwprobe_dump [1]

---

Changes in V2:
 - Fix typo in first commit title (fatorize->factorize)
 - Add Zfa support
 - Fix missing uppercase for Zvkt naming in dt-bindings
 - Add Conor Acked-by on dt-bindings commits
 - Add scalar crypto support from Conor/Evan.
 - Use reporting of bunbled extensions for vector crypto

Clément Léger (18):
  riscv: hwprobe: factorize hwprobe ISA extension reporting
  riscv: hwprobe: add support for scalar crypto ISA extensions
  dt-bindings: riscv: add scalar crypto ISA extensions description
  riscv: add ISA extension parsing for vector crypto extensions
  riscv: hwprobe: export vector crypto ISA extensions
  dt-bindings: riscv: add vector crypto ISA extensions description
  riscv: add ISA extension parsing for Zfh/Zfhmin
  riscv: hwprobe: export Zfh/Zfhmin ISA extensions
  dt-bindings: riscv: add Zfh[min] ISA extensions description
  riscv: add ISA extension parsing for Zihintntl
  riscv: hwprobe: export Zhintntl ISA extension
  dt-bindings: riscv: add Zihintntl ISA extension description
  riscv: add ISA extension parsing for Zvfh[min]
  riscv: hwprobe: export Zvfh[min] ISA extensions
  dt-bindings: riscv: add Zvfh[min] ISA extension description
  riscv: add ISA extension parsing for Zfa
  riscv: hwprobe: export Zfa ISA extension
  dt-bindings: riscv: add Zfa ISA extension description

Evan Green (1):
  riscv: add ISA extension parsing for scalar crypto

 .../devicetree/bindings/riscv/extensions.yaml | 210 ++++++++++++++++++
 Documentation/riscv/hwprobe.rst               |  81 +++++++
 arch/riscv/include/asm/hwcap.h                |  33 ++-
 arch/riscv/include/uapi/asm/hwprobe.h         |  26 +++
 arch/riscv/kernel/cpufeature.c                | 165 ++++++++++++--
 arch/riscv/kernel/sys_riscv.c                 |  64 ++++--
 6 files changed, 543 insertions(+), 36 deletions(-)