Re: [PATCH] drm/amd/display: Restore 5s vbl offdelay for NV3x+ DGPUs

[Mario Limonciello <mario.limonciello@amd.com>]

On 4/22/26 11:29, sunpeng.li@amd.com wrote:
> From: Leo Li <sunpeng.li@amd.com>
> 
> [Why]
> 
> Rapid vblank off is causing flip-done timeouts for NV3x and newer
> family of GPUs that support more idle optimization features.
> 
> A proper fix requires further investigation. In lieu of it, let's
> workaround it for now.
> 
> [How]
> 
> For NV3x and newer family of DGPUs, restore the old 5s vblank off timer.

Why would it be dGPU only though?  I thought we have various reports of 
flip_done timeouts for APUs too.

Is your theory they're different root causes?

> 
> Fixes: 9b47278cec98 ("drm/amd/display: temp w/a for dGPU to enter idle optimizations")
> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3787
> Link: https://lore.kernel.org/amd-gfx/20260217191632.1243826-1-sysdadmin@m1k.cloud/
> Signed-off-by: Leo Li <sunpeng.li@amd.com>
> Tested-by: Michele Palazzi <sysdadmin@m1k.cloud>
> ---
>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c  | 18 +++++++++++++++---
>   1 file changed, 15 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 3fa4dbda4517c..ce5063928413c 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -9511,9 +9511,21 @@ static void manage_dm_interrupts(struct amdgpu_device *adev,
>   	if (acrtc_state) {
>   		timing = &acrtc_state->stream->timing;
>   
> -		if (amdgpu_ip_version(adev, DCE_HWIP, 0) <
> -			   IP_VERSION(3, 5, 0) ||
> -			   !(adev->flags & AMD_IS_APU)) {
> +		if (amdgpu_ip_version(adev, DCE_HWIP, 0) >=
> +		      IP_VERSION(3, 2, 0) &&
> +		      !(adev->flags & AMD_IS_APU)) {
> +			/*
> +			 * DGPUs NV3x and newer that support idle optimizations
> +			 * experience intermittent flip-done timeouts on cursor
> +			 * updates. Restore 5s offdelay behavior for now.
> +			 *
> +			 * Discussion on the issue:
> +			 * https://lore.kernel.org/amd-gfx/20260217191632.1243826-1-sysdadmin@m1k.cloud/
> +			 */
> +			config.offdelay_ms = 5000;
> +			config.disable_immediate = false;
> +		} else if (amdgpu_ip_version(adev, DCE_HWIP, 0) <
> +			     IP_VERSION(3, 5, 0)) {
>   			/*
>   			 * Older HW and DGPU have issues with instant off;
>   			 * use a 2 frame offdelay.