On 2026-06-17 00:35, Matthew Schwartz wrote:
> On 6/16/26 1:18 PM, [email protected] wrote:
>
> [...]
>
>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
>> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
>> index c9916ed0ddc14..8a6b732cf80c8 100644
>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
>> @@ -281,7 +281,14 @@ static inline int amdgpu_dm_crtc_set_vblank(struct
>> drm_crtc *crtc, bool enable)
>> drm_crtc_vblank_restore(crtc);
>> }
>>
>> - if (dc_supports_vrr(dm->dc->ctx->dce_version)) {
>> + /*
>> + * On DCN, VUPDATE_NO_LOCK is the single OTG interrupt used to deliver
>> + * vblank and pageflip completion events, so enable it whenever vblank
>> + * is enabled. On DCE, vupdate is only needed in VRR mode.
>> + */
>> + if (amdgpu_ip_version(adev, DCE_HWIP, 0) != 0) {
>> + rc = amdgpu_dm_crtc_set_vupdate_irq(crtc, enable);
>> + } else if (dc_supports_vrr(dm->dc->ctx->dce_version)) {
>
> Hi Leo (dropping Stable),
>
> This arms VUPDATE_NO_LOCK on all of DCN, but
> amdgpu_dm_handle_vrr_transition() still disables it when switching from VRR
> active -> inactive. This causes a new flip_done timed out event when a
> compositor like gamescope disables VRR while it's already active.
Good catch, I wonder why the kms_vrr IGT tests did not catch this...
I'll roll your fix into v2 with your signed-off-by and co-authored-by.
Thanks,
Leo
>
> I had to fix it up with something like:
>
> 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 e09c0eb9f865..ee337ca816cf 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -10085,8 +10085,16 @@ static void amdgpu_dm_handle_vrr_transition(struct
> amdgpu_display_manager *dm,
> struct dm_crtc_state *old_state,
> struct dm_crtc_state *new_state)
> {
> + struct amdgpu_device *adev = dm->adev;
> bool old_vrr_active = amdgpu_dm_crtc_vrr_active(old_state);
> bool new_vrr_active = amdgpu_dm_crtc_vrr_active(new_state);
> + /*
> + * On DCN, VUPDATE_NO_LOCK is the sole vblank and pageflip completion
> + * source and amdgpu_dm_crtc_set_vblank() keeps it armed whenever
> + * vblank is enabled, so it must not be toggled with the VRR state.
> + * Only DCE gates vupdate on VRR.
> + */
> + bool vrr_gates_vupdate = amdgpu_ip_version(adev, DCE_HWIP, 0) == 0;
>
> if (!old_vrr_active && new_vrr_active) {
> /* Transition VRR inactive -> active:
> @@ -10097,7 +10105,8 @@ static void amdgpu_dm_handle_vrr_transition(struct
> amdgpu_display_manager *dm,
> * We also need vupdate irq for the actual core vblank handling
> * at end of vblank.
> */
> - WARN_ON(amdgpu_dm_crtc_set_vupdate_irq(new_state->base.crtc,
> true) != 0);
> + if (vrr_gates_vupdate)
> +
> WARN_ON(amdgpu_dm_crtc_set_vupdate_irq(new_state->base.crtc, true) != 0);
> WARN_ON(drm_crtc_vblank_get(new_state->base.crtc) != 0);
> drm_dbg_driver(new_state->base.crtc->dev, "%s: crtc=%u VRR
> off->on: Get vblank ref\n",
> __func__, new_state->base.crtc->base.id);
> @@ -10113,7 +10122,8 @@ static void amdgpu_dm_handle_vrr_transition(struct
> amdgpu_display_manager *dm,
> /* Transition VRR active -> inactive:
> * Allow vblank irq disable again for fixed refresh rate.
> */
> - WARN_ON(amdgpu_dm_crtc_set_vupdate_irq(new_state->base.crtc,
> false) != 0);
> + if (vrr_gates_vupdate)
> +
> WARN_ON(amdgpu_dm_crtc_set_vupdate_irq(new_state->base.crtc, false) != 0);
> drm_crtc_vblank_put(new_state->base.crtc);
> drm_dbg_driver(new_state->base.crtc->dev, "%s: crtc=%u VRR
> on->off: Drop vblank ref\n",
> __func__, new_state->base.crtc->base.id);
>
> Feel free to fold some version of this into the next version if it makes
> sense, or pick it up with my s-o-b.
>
> Thanks,
> Matthew
>
