Re: [PATCH V2 3/3] platform/x86/intel/pmc/arl: Put GNA device in D3

[Kuppuswamy Sathyanarayanan]

On 2/27/24 11:01 AM, David E. Box wrote:
> As is the case on Meteor Lake, the Gaussian & Neural Accelerator (GNA)
> device is powered by BIOS to D0 by default. If no driver is loaded, this
> will cause the Package C state to be limited to PC2, leading to
> significant power consumption and decrease in batter life.  Put the GNA
> device in D3 by default if no driver is loaded for it.

Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>

>
> Fixes: 83f168a1a437 ("platform/x86/intel/pmc: Add Arrow Lake S support to intel_pmc_core driver")
> Signed-off-by: David E. Box <david.e.box@xxxxxxxxxxxxxxx>
> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> ---
>
> V2 - Better explain the issue in the changelog and spell out GNA.
>
>  drivers/platform/x86/intel/pmc/arl.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/platform/x86/intel/pmc/arl.c b/drivers/platform/x86/intel/pmc/arl.c
> index 683ae828276b..34b4cd23bfe5 100644
> --- a/drivers/platform/x86/intel/pmc/arl.c
> +++ b/drivers/platform/x86/intel/pmc/arl.c
> @@ -673,6 +673,7 @@ static struct pmc_info arl_pmc_info_list[] = {
>  };
>  
>  #define ARL_NPU_PCI_DEV			0xad1d
> +#define ARL_GNA_PCI_DEV			0xae4c
>  /*
>   * Set power state of select devices that do not have drivers to D3
>   * so that they do not block Package C entry.
> @@ -680,6 +681,7 @@ static struct pmc_info arl_pmc_info_list[] = {
>  static void arl_d3_fixup(void)
>  {
>  	pmc_core_set_device_d3(ARL_NPU_PCI_DEV);
> +	pmc_core_set_device_d3(ARL_GNA_PCI_DEV);
>  }
>  
>  static int arl_resume(struct pmc_dev *pmcdev)

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer