Re: [PATCH 1/2] CPUFREQ: Enable acpi-cpufreq driver for VIA/Centaur CPUs

Harald Welte
2009-06-09T02:20:26Z

On Mon, Jun 08, 2009 at 11:35:12AM -0700, Linus Torvalds wrote:
> Hmm. This all really should be just
>
> static int check_est_cpu(unsigned int cpuid)
> {
> struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
> return cpu_has(cpu, X86_FEATURE_EST);
> }
>
> I suspect, with no vendor tests. That's the whole _point_ of CPU features,
> after all.

That's what I was thinking, too. If there was no such vendor test, it would
have worked ever since the code was written (the C7 is by far not a new
component, it's around for years).

> If some vendor claims EST but doesn't actually support the EST interfaces,
> we should just have fixups to clear the bit in the per-vendor cpuinfo
> code, not in some random driver.

agreed.

> The only thing that makes me nervous about this is how close to 2.6.30 we
> are. I'd be happier if this was resolved by doing this as a patch
> post-2.6.30, and then adding 'stable@kernel.org' as a Cc: tag, and
> backporting it to 2.6.30.1 if no problems appear.
>
> It's not like this is a regression, I think.
>
> Does that sound like a reasonable plan?

Sounds fine with me. But what I would definitely suggest merging before 2.6.30
is the marking e_powersaver EXPERIMENTAL + DANGEROUS patch.

Regards,
--
- Harald Welte <HaraldWelte@viatech.com> http://linux.via.com.tw/
============================================================================
VIA Free and Open Source Software Liaison