[PATCH] drm/xe/d3cold: Set power state to D3Cold during s2idle/s3

[Nilawar, Badal]

On 27-03-2025 21:49, Badal Nilawar wrote:
Hi Rodrigo,

> According to pci core guidelines, pci_save_config is recommended when the
> driver explicitly needs to set the pci power state. As of now xe kmd is
> only doing pci_save_config while entering to s2idle/s3 state, which makes
> pci core think that device driver has already applied required pci power
> state. This leads to GPU remain in D0 state. To fix the issue setting
> the pci power state to D3Cold.
>
> Fixes:dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
> Cc: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Signed-off-by: Badal Nilawar <badal.nilawar at intel.com>
> Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
> ---
>   drivers/gpu/drm/xe/xe_pci.c | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
> index 7046e7e9a6c7..3317d475be79 100644
> --- a/drivers/gpu/drm/xe/xe_pci.c
> +++ b/drivers/gpu/drm/xe/xe_pci.c
> @@ -932,6 +932,7 @@ static int xe_pci_suspend(struct device *dev)
>   
>   	pci_save_state(pdev);
>   	pci_disable_device(pdev);
> +	pci_set_power_state(pdev, PCI_D3cold);

Another approach to avoid calling pci_save_state and 
pci_set_power_state, allowing the PCI core to manage this.
Currently, the above change aligns with the Xe RPM suspend flow.

Regards,
Badal

>   
>   	return 0;
>   }