[PATCH] drm/amdgpu: resolve s3 hang for r7340

[Paul Menzel]

Dear Zhenneng,


Thank you for your patch.

Am 28.03.22 um 06:05 schrieb Zhenneng Li:
> This is a workaround for s3 hang for r7340(amdgpu).

Is it hanging when resuming from S3? Maybe also use the line below for 
the commit message summary:

drm/amdgpu: Add 1 ms delay to init handler to fix s3 resume hang

Also, please add a space before the ( in “r7340(amdgpu)”.

> When we test s3 with r7340 on arm64 platform, graphics card will hang up,
> the error message are as follows:
> Mar  4 01:14:11 greatwall-GW-XXXXXX-XXX kernel: [    1.599374][ 7] [  T291] amdgpu 0000:02:00.0: fb0: amdgpudrmfb frame buffer device
> Mar  4 01:14:11 greatwall-GW-XXXXXX-XXX kernel: [    1.612869][ 7] [  T291] [drm:amdgpu_device_ip_late_init [amdgpu]] *ERROR* late_init of IP block <si_dpm> failed -22
> Mar  4 01:14:11 greatwall-GW-XXXXXX-XXX kernel: [    1.623392][ 7] [  T291] amdgpu 0000:02:00.0: amdgpu_device_ip_late_init failed
> Mar  4 01:14:11 greatwall-GW-XXXXXX-XXX kernel: [    1.630696][ 7] [  T291] amdgpu 0000:02:00.0: Fatal error during GPU init
> Mar  4 01:14:11 greatwall-GW-XXXXXX-XXX kernel: [    1.637477][ 7] [  T291] [drm] amdgpu: finishing device.

The prefix in the beginning is not really needed. Only the stuff after 
`kernel: `.

Maybe also add the output of `lspci -nn -s …` for that r7340 device.

> Change-Id: I5048b3894c0ca9faf2f4847ddab61f9eb17b4823

Without the Gerrit instance this belongs to, the Change-Id is of no use 
in the public.

> Signed-off-by: Zhenneng Li <lizhenneng at kylinos.cn>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 3987ecb24ef4..1eced991b5b2 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -2903,6 +2903,8 @@ static void amdgpu_device_delayed_init_work_handler(struct work_struct *work)
>   		container_of(work, struct amdgpu_device, delayed_init_work.work);
>   	int r;
>   
> +	mdelay(1);
> +

Wow, I wonder how long it took you to find that workaround.

>   	r = amdgpu_ib_ring_tests(adev);
>   	if (r)
>   		DRM_ERROR("ib ring test failed (%d).\n", r);


Kind regards,

Paul