[PATCH v3 2/7] RISC-V: Add a syscall for HW probing

[Conor Dooley]

On Tue, Feb 21, 2023 at 11:08:53AM -0800, Evan Green wrote:
> We don't have enough space for these all in ELF_HWCAP{,2} and there's no
> system call that quite does this, so let's just provide an arch-specific
> one to probe for hardware capabilities.  This currently just provides
> m{arch,imp,vendor}id, but with the key-value pairs we can pass more in
> the future.
> 
> Co-developed-by: Palmer Dabbelt <palmer at rivosinc.com>
> Signed-off-by: Palmer Dabbelt <palmer at rivosinc.com>
> Signed-off-by: Evan Green <evan at rivosinc.com>

> +static
> +int do_riscv_hwprobe(struct riscv_hwprobe __user *pairs, long pair_count,
> +		      long cpu_count, unsigned long __user *cpus_user,
> +		      unsigned long flags)

I almost feel bad commenting this, but this is now the only function
split like this w/ the static on its own line.

With the same caveat about ignorance about glibc's desires & lingering
doubt as to whether this interface is the right way to go, this looks
good to me now.
I'm reluctant to give an R-b for the latter reason, but assuming the
Higher Power deem this approach acceptable:
Reviewed-by: Conor Dooley <conor.dooley at microchip.com>

Cheers,
Conor.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 228 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-riscv/attachments/20230227/b7f54ee3/attachment.sig>