[PATCH v1 1/1] platform/x86: p2sb: Don't fail if unknown CPU is found

[PATCH v1 1/1] platform/x86: p2sb: Don't fail if unknown CPU is found

[Andy Shevchenko]

We have accessing P2SB from a very few places for quite known hardware.

When a new SoC appears in intel-family.h it's not obvious that it needs
to be added to p2sb.c as well. Instead, provide default BDF and refactor
p2sb_get_devfn() to always succeed. If in the future we would need to
exclude something, we may add a list of unsupported IDs.

Without this change the iTCO on Intel Commet Lake SoCs became unavailable:

  i801_smbus 0000:00:1f.4: failed to create iTCO device

Fixes: 5c7b9167ddf8 ("i2c: i801: convert to use common P2SB accessor")
Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/platform/x86/p2sb.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/platform/x86/p2sb.c b/drivers/platform/x86/p2sb.c
index 384d0962ae93..1cf2471d54dd 100644
--- a/drivers/platform/x86/p2sb.c
+++ b/drivers/platform/x86/p2sb.c
@@ -19,26 +19,23 @@
 #define P2SBC			0xe0
 #define P2SBC_HIDE		BIT(8)
 
+#define P2SB_DEVFN_DEFAULT	PCI_DEVFN(31, 1)
+
 static const struct x86_cpu_id p2sb_cpu_ids[] = {
 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT,	PCI_DEVFN(13, 0)),
-	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D,	PCI_DEVFN(31, 1)),
-	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_D,	PCI_DEVFN(31, 1)),
-	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE,		PCI_DEVFN(31, 1)),
-	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L,		PCI_DEVFN(31, 1)),
-	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE,		PCI_DEVFN(31, 1)),
-	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L,		PCI_DEVFN(31, 1)),
 	{}
 };
 
 static int p2sb_get_devfn(unsigned int *devfn)
 {
+	unsigned int fn = P2SB_DEVFN_DEFAULT;
 	const struct x86_cpu_id *id;
 
 	id = x86_match_cpu(p2sb_cpu_ids);
-	if (!id)
-		return -ENODEV;
+	if (id)
+		fn = (unsigned int)id->driver_data;
 
-	*devfn = (unsigned int)id->driver_data;
+	*devfn = fn;
 	return 0;
 }
 
-- 
2.35.1

RE: [PATCH v1 1/1] platform/x86: p2sb: Don't fail if unknown CPU is found

[Limonciello, Mario]

[Public]

> -----Original Message-----
> From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Sent: Friday, November 4, 2022 10:49
> To: Hans de Goede <hdegoede@redhat.com>; Andy Shevchenko
> <andriy.shevchenko@linux.intel.com>; platform-driver-
> x86@vger.kernel.org; linux-kernel@vger.kernel.org
> Cc: Mark Gross <markgross@kernel.org>; Jarkko Nikula
> <jarkko.nikula@linux.intel.com>
> Subject: [PATCH v1 1/1] platform/x86: p2sb: Don't fail if unknown CPU is
> found
> 
> We have accessing P2SB from a very few places for quite known hardware.
> 
> When a new SoC appears in intel-family.h it's not obvious that it needs
> to be added to p2sb.c as well. Instead, provide default BDF and refactor
> p2sb_get_devfn() to always succeed. If in the future we would need to
> exclude something, we may add a list of unsupported IDs.
> 
> Without this change the iTCO on Intel Commet Lake SoCs became

Isn't it "Comet Lake"?

> unavailable:
> 
>   i801_smbus 0000:00:1f.4: failed to create iTCO device
> 
> Fixes: 5c7b9167ddf8 ("i2c: i801: convert to use common P2SB accessor")
> Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  drivers/platform/x86/p2sb.c | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/platform/x86/p2sb.c b/drivers/platform/x86/p2sb.c
> index 384d0962ae93..1cf2471d54dd 100644
> --- a/drivers/platform/x86/p2sb.c
> +++ b/drivers/platform/x86/p2sb.c
> @@ -19,26 +19,23 @@
>  #define P2SBC			0xe0
>  #define P2SBC_HIDE		BIT(8)
> 
> +#define P2SB_DEVFN_DEFAULT	PCI_DEVFN(31, 1)
> +
>  static const struct x86_cpu_id p2sb_cpu_ids[] = {
>  	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT,
> 	PCI_DEVFN(13, 0)),
> -	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D,
> 	PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_D,
> 	PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE,
> 	PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L,
> 	PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE,
> 	PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L,
> 	PCI_DEVFN(31, 1)),
>  	{}
>  };
> 
>  static int p2sb_get_devfn(unsigned int *devfn)
>  {
> +	unsigned int fn = P2SB_DEVFN_DEFAULT;
>  	const struct x86_cpu_id *id;
> 
>  	id = x86_match_cpu(p2sb_cpu_ids);
> -	if (!id)
> -		return -ENODEV;
> +	if (id)
> +		fn = (unsigned int)id->driver_data;
> 
> -	*devfn = (unsigned int)id->driver_data;
> +	*devfn = fn;
>  	return 0;
>  }
> 
> --
> 2.35.1

Re: [PATCH v1 1/1] platform/x86: p2sb: Don't fail if unknown CPU is found

[Andy Shevchenko]

On Fri, Nov 04, 2022 at 03:58:22PM +0000, Limonciello, Mario wrote:
> > -----Original Message-----
> > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > Sent: Friday, November 4, 2022 10:49

...

> > We have accessing P2SB from a very few places for quite known hardware.
> > 
> > When a new SoC appears in intel-family.h it's not obvious that it needs
> > to be added to p2sb.c as well. Instead, provide default BDF and refactor
> > p2sb_get_devfn() to always succeed. If in the future we would need to
> > exclude something, we may add a list of unsupported IDs.
> > 
> > Without this change the iTCO on Intel Commet Lake SoCs became
> 
> Isn't it "Comet Lake"?

Right, thanks!

In any case I would like to have Jarkko's Tested-by before proceeding with
this. Hence v2 is warranted to appear.

> > unavailable:
> > 
> >   i801_smbus 0000:00:1f.4: failed to create iTCO device

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v1 1/1] platform/x86: p2sb: Don't fail if unknown CPU is found

[Jarkko Nikula]

Hi

On 11/4/22 19:22, Andy Shevchenko wrote:
> On Fri, Nov 04, 2022 at 03:58:22PM +0000, Limonciello, Mario wrote:
>> Isn't it "Comet Lake"?
> 
> Right, thanks!
> 
> In any case I would like to have Jarkko's Tested-by before proceeding with
> this. Hence v2 is warranted to appear.
> 
Yes, iTCO registration works again with this patch and is functioning, 
i.e. able to reset the machine.

Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>

Re: [PATCH v1 1/1] platform/x86: p2sb: Don't fail if unknown CPU is found

[Hans de Goede]

Hi,

On 11/4/22 16:49, Andy Shevchenko wrote:
> We have accessing P2SB from a very few places for quite known hardware.
> 
> When a new SoC appears in intel-family.h it's not obvious that it needs
> to be added to p2sb.c as well. Instead, provide default BDF and refactor
> p2sb_get_devfn() to always succeed. If in the future we would need to
> exclude something, we may add a list of unsupported IDs.
> 
> Without this change the iTCO on Intel Commet Lake SoCs became unavailable:
> 
>   i801_smbus 0000:00:1f.4: failed to create iTCO device
> 
> Fixes: 5c7b9167ddf8 ("i2c: i801: convert to use common P2SB accessor")
> Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Thanks. I've merged this now, with the Commet Lake spelling error
fixed and with Jarko's Tested-by added.

I'll include this in my upcoming fixes pull-req to Linus.

Regards,

Hans




> ---
>  drivers/platform/x86/p2sb.c | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/platform/x86/p2sb.c b/drivers/platform/x86/p2sb.c
> index 384d0962ae93..1cf2471d54dd 100644
> --- a/drivers/platform/x86/p2sb.c
> +++ b/drivers/platform/x86/p2sb.c
> @@ -19,26 +19,23 @@
>  #define P2SBC			0xe0
>  #define P2SBC_HIDE		BIT(8)
>  
> +#define P2SB_DEVFN_DEFAULT	PCI_DEVFN(31, 1)
> +
>  static const struct x86_cpu_id p2sb_cpu_ids[] = {
>  	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT,	PCI_DEVFN(13, 0)),
> -	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D,	PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_D,	PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE,		PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L,		PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE,		PCI_DEVFN(31, 1)),
> -	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L,		PCI_DEVFN(31, 1)),
>  	{}
>  };
>  
>  static int p2sb_get_devfn(unsigned int *devfn)
>  {
> +	unsigned int fn = P2SB_DEVFN_DEFAULT;
>  	const struct x86_cpu_id *id;
>  
>  	id = x86_match_cpu(p2sb_cpu_ids);
> -	if (!id)
> -		return -ENODEV;
> +	if (id)
> +		fn = (unsigned int)id->driver_data;
>  
> -	*devfn = (unsigned int)id->driver_data;
> +	*devfn = fn;
>  	return 0;
>  }
>