> -----Original Message----- > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Sent: Thursday, February 22, 2024 2:55 AM > To: Vivi, Rodrigo <rodrigo.vivi@xxxxxxxxx> > Cc: Manna, Animesh <animesh.manna@xxxxxxxxx>; intel- > gfx@xxxxxxxxxxxxxxxxxxxxx; Hogander, Jouni <jouni.hogander@xxxxxxxxx>; > Murthy, Arun R <arun.r.murthy@xxxxxxxxx> > Subject: Re: [PATCH v3] drm/i915/panelreplay: Panel replay workaround with > VRR > > On Wed, Feb 21, 2024 at 11:08:18PM +0200, Ville Syrjälä wrote: > > On Wed, Feb 21, 2024 at 03:58:48PM -0500, Rodrigo Vivi wrote: > > > On Wed, Feb 21, 2024 at 08:19:35PM +0000, Manna, Animesh wrote: > > > > > > > > > > > > > -----Original Message----- > > > > > From: Vivi, Rodrigo <rodrigo.vivi@xxxxxxxxx> > > > > > Sent: Tuesday, February 20, 2024 11:12 PM > > > > > To: Manna, Animesh <animesh.manna@xxxxxxxxx> > > > > > Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx; > > > > > ville.syrjala@xxxxxxxxxxxxxxx; Hogander, Jouni > > > > > <jouni.hogander@xxxxxxxxx>; Murthy, Arun R > > > > > <arun.r.murthy@xxxxxxxxx> > > > > > Subject: Re: [PATCH v3] drm/i915/panelreplay: Panel replay > > > > > workaround with VRR > > > > > > > > > > On Tue, Feb 20, 2024 at 07:49:19PM +0530, Animesh Manna wrote: > > > > > > Panel Replay VSC SDP not getting sent when VRR is enabled and > > > > > > W1 and > > > > > > W2 are 0. So Program Set Context Latency in > > > > > TRANS_SET_CONTEXT_LATENCY > > > > > > register to at least a value of 1. > > > > > > > > > > > > HSD: 14015406119 > > > > > > > > > > Unnecessary mark since the wa_name already is a pointer to the HSD. > > > > > > > > > > > > > > > > > v1: Initial version. > > > > > > v2: Update timings stored in adjusted_mode struct. [Ville] > > > > > > v3: Add WA in compute_config(). [Ville] > > > > > > > > > > > > Signed-off-by: Animesh Manna <animesh.manna@xxxxxxxxx> > > > > > > --- > > > > > > drivers/gpu/drm/i915/display/intel_dp.c | 12 ++++++++++++ > > > > > > 1 file changed, 12 insertions(+) > > > > > > > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c > > > > > > b/drivers/gpu/drm/i915/display/intel_dp.c > > > > > > index 217196196e50..eb0fa513cd0f 100644 > > > > > > --- a/drivers/gpu/drm/i915/display/intel_dp.c > > > > > > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > > > > > > @@ -2948,6 +2948,18 @@ intel_dp_compute_config(struct > > > > > > intel_encoder > > > > > *encoder, > > > > > > intel_dp_compute_vsc_sdp(intel_dp, pipe_config, > conn_state); > > > > > > intel_dp_compute_hdr_metadata_infoframe_sdp(intel_dp, > > > > > pipe_config, > > > > > > conn_state); > > > > > > > > > > > > + /* > > > > > > + * WA: HSD-14015406119 > > > > > > > > > > this is not the right one. You should use the lineage one and > > > > > then mark the platforms. > > > > > > > > > > /* wa_14015401596: xe_lpd, xe_hpd */ > > > > > > > > > > or perhaps > > > > > > > > > > /* wa_14015401596: display versions: 13, 14 */ > > > > > > > > > > and also add a check for the display version with it. > > > > > > > > Sure. > > > > > > > > > > > > > > > + * Program Set Context Latency in > TRANS_SET_CONTEXT_LATENCY > > > > > register > > > > > > + * to at least a value of 1 when Panel Replay is enabled with > VRR. > > > > > > + * Value for TRANS_SET_CONTEXT_LATENCY is calculated by > > > > > substracting > > > > > > + * crtc_vdisplay from crtc_vblank_start, so incrementing > > > > > crtc_vblank_start > > > > > > + * by 1 if both are equal. > > > > > > + */ > > > > > > + if (pipe_config->vrr.enable && pipe_config- > >has_panel_replay && > > > > > > + adjusted_mode->crtc_vblank_start == adjusted_mode- > > > > > >crtc_vdisplay) > > > > > > + adjusted_mode->crtc_vblank_start += 1; > > > > > > > > > > why to mess with the vblank start instead of going to > > > > > intel_set_transcoder_timings() and change directly what is > > > > > getting written to the register when the register gets written? > > > > > > > > I have done in previous version of this patch. But as per review > feedback, added now here. > > > > https://patchwork.freedesktop.org/series/129632/#rev1 > > > > https://patchwork.freedesktop.org/series/129632/#rev2 > > > > > > > > > > > > > > In case the answer is becasue by then we don't have the > > > > > vrr.enable or something like that, then we should consider move > > > > > around when we set that register? > > > > > > > > This was not acceptable in earlier versions. As per feedback instead of > atomic-commit need to add in compute-config phase. > > > > > > > > > > > > > > or perhaps create a specific flag? one extra variable, 3 less comment > lines... > > > > > > > > The above comment is not clear to me, can you please elaborate more > here. > > > > > > something like: > > > > > > @intel_dp_compute_config() > > > > > > +if (pipe_config->vrr.enable && pipe_config->has_panel_replay && > > > + adjusted_mode->crtc_vblank_start == adjusted_mode-crtc_vdisplay) > > > + pipe_config->mode_flags = > > > +I915_MODE_FLAG_MIN_TRANS_CONTEXT_LATENCY_1 > > > > > > then > > > @intel_set_transcoder_timings() > > > +u32 context_latency; > > > > > > +if (crtc_state->mode_flags & > I915_MODE_FLAG_MIN_TRANS_CONTEXT_LATENCY_1) > > > + context_latency = 1; > > > +else > > > + crtc_vblank_start - crtc_vdisplay; > > > > > > -crtc_vblank_start - crtc_vdisplay); > > > +context_latency); > > > > > > Ville, thoughts? > > > > I think what we need is a intel_crtc_vblank_delay() or somesuch thing > > that accounts for all the things (eg. this w/a, dsb execution latency > > when we start to use dsb for double buffered registers, etc). > > And it should probably be called from some central place so that it > > works for all output types. intel_crtc_compute_config() comes to mind, > > but I guess we need to first ponder whether there are bits of code > > being executed prior to that that would need to know the actual > > vblank_start... > > PSR2 itself might have a chicken vs. egg issue here. Wehether we can enable > it not depends on the length of the vblank. Whether that means the full > vblank or the pipe's shrunken vblank I don't know. Someone needs to figure > that out. Added a centralized intel_crtc_vblank_delay() in v4 but as this WA is specific for panel replay which will be supported by DP/EDP so called from encoder-compute-config() instead of crtc-compute-config. Regards, Animesh > > -- > Ville Syrjälä > Intel
