[PATCH] drm/xe: Restore pci state upon resume

[Lucas De Marchi]

On Thu, Sep 12, 2024 at 05:20:40PM GMT, Rodrigo Vivi wrote:
>On Thu, Sep 12, 2024 at 03:11:12PM -0500, Lucas De Marchi wrote:
>> On Thu, Sep 12, 2024 at 03:05:30PM GMT, Rodrigo Vivi wrote:
>> > The pci state was saved, but not restored. Restore
>> > right after the power state transition request like
>> > every other driver.
>> >
>> > Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
>>
>> oh, no
>>
>> > Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
>> > ---
>> > drivers/gpu/drm/xe/xe_pci.c | 2 ++
>> > 1 file changed, 2 insertions(+)
>> >
>> > diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
>> > index 5ba4ec229494..6d29ef4b396f 100644
>> > --- a/drivers/gpu/drm/xe/xe_pci.c
>> > +++ b/drivers/gpu/drm/xe/xe_pci.c
>> > @@ -949,6 +949,8 @@ static int xe_pci_resume(struct device *dev)
>> > 	if (err)
>> > 		return err;
>> >
>> > +	pci_restore_state(pdev);
>> > +
>>
>> something bad happened... I was sure this line was here before. Indeed.
>> git log -L:xe_pci_resume:drivers/gpu/drm/xe/xe_pci.c to the rescue
>>
>> See commit f6761c68c0ac ("drm/xe/display: Improve s2idle handling.")
>
>hmmm...
>Perhaps
>
>Fixes: f6761c68c0ac ("drm/xe/display: Improve s2idle handling.")
>Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>
>then?!

yes, reading that patch I don't understand why it got removed.

Lucas De Marchi

>
>The restoration shouldn't have anything to do with that case.
>and it pairs with pci_save_state(pdev) is still there...
>
>It is not in i915, but I have an i915 patch to add the restore
>there as well.
>
>Also, I might as well in a follow up bring back the
>pci_set_power_state(pdev, PCI_D3hot) to Xe.
>This is probably the right way, aligns with all other drivers
>and i915. So that shouldn't be the cause of the power drainage
>on suspend anyway, or i915 would be also draining it.
>
>>
>> Lucas De Marchi
>>
>> > 	err = pci_enable_device(pdev);
>> > 	if (err)
>> > 		return err;
>> > --
>> > 2.46.0
>> >