[PATCH] drm/amdgpu: fix vblank_time when displays are off

[Michel Dänzer]

On 30/06/17 05:16 AM, Alex Deucher wrote:
> If the displays are off, set the vblank time to max to make
> sure mclk switching is enabled.  Avoid mclk getting set
> to high when no displays are attached.
> 
> bug: https://bugs.freedesktop.org/show_bug.cgi?id=101528
> fixes: 09be4a5219 (drm/amd/powerplay/smu7: add vblank check for mclk switching (v2))
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> Cc: stable at vger.kernel.org
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c
> index c6dba1e..8b8eda7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c
> @@ -838,6 +838,9 @@ static int amdgpu_cgs_get_active_displays_info(struct cgs_device *cgs_device,
>  		return -EINVAL;
>  
>  	mode_info = info->mode_info;
> +	if (mode_info)
> +		/* if the displays are off, vblank time is max */
> +		mode_info->vblank_time_us = 0xffffffff;
>  
>  	if (adev->mode_info.num_crtc && adev->mode_info.mode_config_initialized) {
>  		list_for_each_entry(crtc,
> 

Reviewed-by: Michel Dänzer <michel.daenzer at amd.com>


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer