Re: [PATCH v3 2/4] i2c: piix4: Move SB800_PIIX4_FCH_PM_ADDR definition to amd_node.h

From: Mario Limonciello
Date: Sat Apr 12 2025 - 15:51:21 EST




On 4/12/25 14:44, Ingo Molnar wrote:

* Borislav Petkov <bp@xxxxxxxxx> wrote:

On Fri, Apr 11, 2025 at 07:09:56AM -0500, Mario Limonciello wrote:
I was aiming for a header that we would conceivably use in all these places
anyway.

Can you suggest a more fitting existing header? A new one felt too heavy
for a single register define.

No, the logic is: put it in the *right* header. Not in the "whatever-works"
header.

Yeah, it's the Linux kernel equivalent of: 'if you touch it, you own it',
a.k.a. 'no good deed goes unpunished'. ;-)


Ya.

So you can easily add a

arch/x86/include/asm/platform.h

header which contains exactly platform stuff. And FCH sounds like a platform
thing to me. Or at least southbridge or whatever that thing is called now. It
certainly ain't part of the CPU so platform should be more fitting.

Unless someone has a better idea...

Yeah, so I think we can create a brand new <asm/amd_sb.h> header or so,
because it's an AMD SB800 southbridge chipset register? We already have
<asm/amd_nb.h>.

'platform' might be a bit too generic and fungible I think: often the
northbridge and the CPU is considered part of a 'platform' too.

Thanks,

Ingo

SB800 is pre-Zen stuff. It's "before my time" - I guess that's the precursor to FCH being in the SoC but has the same functionality.

So I'm thinking <asm/amd_fch.h>.