[v4,0/6] Add some validation for vector, vector crypto and fp stuff

Message

Conor Dooley March 12, 2025, 1:11 p.m. UTC

From: Conor Dooley <[e-mail]>

Yo,

This series is partly leveraging Clement's work adding a validate
callback in the extension detection code so that things like checking
for whether a vector crypto extension is usable can be done like:
	has_extension(<vector crypto>)
rather than
	has_vector() && has_extension(<vector crypto>)
which Eric pointed out was a poor design some months ago.

The rest of this is adding some requirements to the bindings that
prevent combinations of extensions disallowed by the ISA.

There's a bunch of over-long lines in here, but I thought that the
over-long lines were clearer than breaking them up.

Cheers,
Conor.

(I've been unintentionally sitting on this for a month, hope I
haven't omitted anything as a result)

v4:
- Zvbb -> vector_crypto_validate()
- remove copy-pasta section of commit messages
- Add commentary justifying !EPROBE_DEFER cases
- EPROBE_DEFER where possible (one instance, zve32x check)

v3:
- rebase on v6.14-rc1
- split vector crypto validation patch into vector validation and vector
  crypto validation
- fix zve64x requiring extension list to match Eric's PR

v2:
- Fix an inverted clause Clément pointed out
- Add Zvbb validation, that I had missed accidentally
- Drop the todo about checking the number of validation rounds,
  I tried in w/ qemu's max cpu and things looked right

CC: Eric Biggers <[e-mail]>
CC: Conor Dooley <[e-mail]>
CC: Rob Herring <[e-mail]>
CC: Krzysztof Kozlowski <[e-mail]>
CC: Paul Walmsley <[e-mail]>
CC: Palmer Dabbelt <[e-mail]>
CC: "Clément Léger" <[e-mail]>
CC: Andy Chiu <[e-mail]>
CC: [e-mail]
CC: [e-mail]
CC: [e-mail]

Conor Dooley (6):
  RISC-V: add vector extension validation checks
  RISC-V: add vector crypto extension validation checks
  RISC-V: add f & d extension validation checks
  dt-bindings: riscv: d requires f
  dt-bindings: riscv: add vector sub-extension dependencies
  dt-bindings: riscv: document vector crypto requirements

 .../devicetree/bindings/riscv/extensions.yaml |  85 +++++++++++
 arch/riscv/include/asm/cpufeature.h           |   3 +
 arch/riscv/kernel/cpufeature.c                | 140 +++++++++++++-----
 3 files changed, 190 insertions(+), 38 deletions(-)