[PATCH v2 1/2] drm/amdgpu: enhance amdgpu_vcn_suspend

[Leo Liu]

On 2021-05-17 11:52 a.m., James Zhu wrote:
> During vcn suspends, stop ring continue to receive new requests,
> and try to wait for all vcn jobs to finish gracefully.
>
> v2: Forced powering gate vcn hardware after few wainting retry.
>
> Signed-off-by: James Zhu <James.Zhu at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c | 22 +++++++++++++++++++++-
>   1 file changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
> index 2016459..9f3a6e7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
> @@ -275,9 +275,29 @@ int amdgpu_vcn_suspend(struct amdgpu_device *adev)
>   {
>   	unsigned size;
>   	void *ptr;
> +	int retry_max = 6;
>   	int i;
>   
> -	cancel_delayed_work_sync(&adev->vcn.idle_work);
> +	for (i = 0; i < adev->vcn.num_vcn_inst; ++i) {
> +		if (adev->vcn.harvest_config & (1 << i))
> +			continue;
> +		ring = &adev->vcn.inst[i].ring_dec;
> +		ring->sched.ready = false;
> +
> +		for (j = 0; j < adev->vcn.num_enc_rings; ++j) {
> +			ring = &adev->vcn.inst[i].ring_enc[j];
> +			ring->sched.ready = false;
> +		}
> +	}
> +
> +	while (retry_max-- && cancel_delayed_work_sync(&adev->vcn.idle_work))
> +		mdelay(5);

I think it's possible to have one pending job unprocessed with VCN when 
suspend sequence getting here, but it shouldn't be more than one, 
cancel_delayed_work_sync probably return false after the first time, so 
calling cancel_delayed_work_sync once should be enough here. we probably 
need to wait longer from:

SOC15_WAIT_ON_RREG(VCN, inst_idx, mmUVD_POWER_STATUS, 1,
         UVD_POWER_STATUS__UVD_POWER_STATUS_MASK);

to make sure the unprocessed job get done.


Regards,

Leo


> +	if (!retry_max && !amdgpu_sriov_vf(adev)) {
> +		if (RREG32_SOC15(VCN, i, mmUVD_STATUS)) {
> +			dev_warn(adev->dev, "Forced powering gate vcn hardware!");
> +			vcn_v3_0_set_powergating_state(adev, AMD_PG_STATE_GATE);
> +		}
> +	}
>   
>   	for (i = 0; i < adev->vcn.num_vcn_inst; ++i) {
>   		if (adev->vcn.harvest_config & (1 << i))