Re: [PATCH v2 0/2] ARM: implement cacheinfo support (for v7/v7m)

From: Dmitry Baryshkov
Date: Thu Nov 07 2024 - 09:35:13 EST


On Thu, Nov 07, 2024 at 02:55:55PM +0100, Linus Walleij wrote:
> Hi Dmitry,
>
> On Mon, Oct 14, 2024 at 3:55 PM Dmitry Baryshkov
> <dmitry.baryshkov@xxxxxxxxxx> wrote:
>
> > Follow the ARM64 platform and implement simple cache information driver.
> > As it reads data from CTR (ARMv6+) and CLIDR (ARMv7+) registers, it is
> > limited to the ARMv7 / ARMv7M, providing simple fallback or just
> > returning -EOPNOTSUPP in case of older platforms.
> >
> > In theory we should be able to skip CLIDR reading and assume that Dcache
> > and Icache (or unified L1 cache) always exist if CTR is supported and
> > returns sensible value. However I think this better be handled by the
> > maintainers of corresponding platforms.
> >
> > Other than just providing information to the userspace, this patchset is
> > required in order to implement L2 cache driver (and in the end CPU
> > frequency scaling) on ARMv7-based Qualcomm devices.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
>
> I added my review tags to the v2 patches, can you put them
> into Russell's patch tracker?

Done, 9432/1 and 9433/1, thank you!

--
With best wishes
Dmitry