Re: [PATCH v4 4/5] platform/x86/amd: pmc: use FCH_PM_BASE definition

[Ingo Molnar <mingo@kernel.org>]

* Yazen Ghannam <yazen.ghannam@amd.com> wrote:

> On Mon, Apr 14, 2025 at 07:26:57PM -0500, Mario Limonciello wrote:
> > From: Mario Limonciello <mario.limonciello@amd.com>
> > 
> > The s2idle mmio quirk uses a scratch register in the FCH.
> > Adjust the code to clarify that.
> > 
> > Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> > ---
> > v4:
> >  * Use fch.h instead
> > ---
> >  arch/x86/include/asm/amd/fch.h            | 1 +
> >  drivers/platform/x86/amd/pmc/pmc-quirks.c | 3 ++-
> >  2 files changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/x86/include/asm/amd/fch.h b/arch/x86/include/asm/amd/fch.h
> > index a5fd91ff92df3..9b32e8a03193e 100644
> > --- a/arch/x86/include/asm/amd/fch.h
> > +++ b/arch/x86/include/asm/amd/fch.h
> > @@ -8,5 +8,6 @@
> >  /* register offsets from PM base */
> >  #define FCH_PM_DECODEEN			0x00
> >  #define FCH_PM_DECODEEN_SMBUS0SEL	GENMASK(20, 19)
> > +#define FCH_PM_SCRATCH			0x80
> >  
> >  #endif
> > diff --git a/drivers/platform/x86/amd/pmc/pmc-quirks.c b/drivers/platform/x86/amd/pmc/pmc-quirks.c
> > index b4f49720c87f6..3c680d2029f62 100644
> > --- a/drivers/platform/x86/amd/pmc/pmc-quirks.c
> > +++ b/drivers/platform/x86/amd/pmc/pmc-quirks.c
> > @@ -8,6 +8,7 @@
> >   * Author: Mario Limonciello <mario.limonciello@amd.com>
> >   */
> >  
> > +#include <asm/amd/fch.h>
> 
> Arch headers should go after linux headers, I think.

That's true, but it's a mostly stylistic requirement these days.

> So that arch stuff can override generic stuff.

Arch headers that override generic stuff are very much supposed to be 
able to build stand-alone and in pretty much any order with other 
headers, with very few exceptions. Ordering dependencies are very much 
frowned upon, because if they don't trigger build failures they can 
result in subtle breakages.

Thanks,

	Ingo