On Thu, 29 Oct 2026, Dmytro Malovanyi <[email protected]> wrote: > nv50_sor_dp_watermark_sst() checks DP_ENHANCED_FRAME_CAP for the > watermark calculation, but the actual enhanced framing enable is > decided in nvkm, in nvkm_dp_train(), nvkm_uoutp_mthd_dp_sst() and > r535_dp_train_target(), with its own copy of the check. Convert all of > them so they keep agreeing with each other. > > dispnv50 uses drm_dp_enhanced_frame_cap(). nvkm does not include the > drm helpers, so add nvkm_dp_enhanced_frame_cap() with the same rule.
Seems reasonable to me, but up to the nouveau maintainers. Reviewed-by: Jani Nikula <[email protected]> > Compile tested only, I don't have nvidia hardware. > > Signed-off-by: Dmytro Malovanyi <[email protected]> > --- > drivers/gpu/drm/nouveau/dispnv50/disp.c | 2 +- > drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c | 2 +- > drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h | 11 +++++++++++ > drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c | 2 +- > .../gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/disp.c | 2 +- > 5 files changed, 15 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c > b/drivers/gpu/drm/nouveau/dispnv50/disp.c > index e91130f93..f965d4811 100644 > --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c > +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c > @@ -1607,7 +1607,7 @@ static bool > nv50_sor_dp_watermark_sst(struct nouveau_encoder *outp, > struct nv50_head *head, struct nv50_head_atom *asyh) > { > - bool enhancedFraming = outp->dp.dpcd[DP_MAX_LANE_COUNT] & > DP_ENHANCED_FRAME_CAP; > + bool enhancedFraming = drm_dp_enhanced_frame_cap(outp->dp.dpcd); > u64 minRate = outp->dp.link_bw * 1000; > unsigned tuSize = 64; > unsigned waterMark; > diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c > b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c > index a109348bd..fbd9935f4 100644 > --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c > +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c > @@ -509,7 +509,7 @@ nvkm_dp_train(struct nvkm_outp *outp, bool retrain) > OUTP_DBG(outp, "training"); > > ior->dp.mst = outp->dp.lt.mst; > - ior->dp.ef = outp->dp.dpcd[DPCD_RC02] & DPCD_RC02_ENHANCED_FRAME_CAP; > + ior->dp.ef = nvkm_dp_enhanced_frame_cap(outp->dp.dpcd); > ior->dp.bw = outp->dp.lt.bw; > ior->dp.nr = outp->dp.lt.nr; > > diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h > b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h > index 9a6be4391..e56acc162 100644 > --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h > +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h > @@ -23,6 +23,17 @@ void nvkm_dp_enable(struct nvkm_outp *, bool auxpwr); > #define DPCD_RC10_SUPPORTED_LINK_RATES(i) > 0x00010 > #define DPCD_RC10_SUPPORTED_LINK_RATES__SIZE > 16 > > +/* Same rule as drm_dp_enhanced_frame_cap() */ > +static inline bool > +nvkm_dp_enhanced_frame_cap(const u8 *dpcd) > +{ > + if (dpcd[DPCD_RC00_DPCD_REV] >= 0x12) > + return true; > + > + return dpcd[DPCD_RC00_DPCD_REV] >= 0x11 && > + (dpcd[DPCD_RC02] & DPCD_RC02_ENHANCED_FRAME_CAP); > +} > + > /* DPCD Link Configuration */ > #define DPCD_LC00_LINK_BW_SET > 0x00100 > #define DPCD_LC01 > 0x00101 > diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c > b/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c > index 377d0e0ce..b0158fc30 100644 > --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c > +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c > @@ -87,7 +87,7 @@ nvkm_uoutp_mthd_dp_sst(struct nvkm_outp *outp, void *argv, > u32 argc) > return 0; > > return ior->func->dp->sst(ior, args->v0.head, > - outp->dp.dpcd[DPCD_RC02] & > DPCD_RC02_ENHANCED_FRAME_CAP, > + nvkm_dp_enhanced_frame_cap(outp->dp.dpcd), > args->v0.watermark, args->v0.hblanksym, > args->v0.vblanksym); > } > > diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/disp.c > b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/disp.c > index f5f22173f..c62900320 100644 > --- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/disp.c > +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/disp.c > @@ -972,7 +972,7 @@ r535_dp_train_target(struct nvkm_outp *outp, u8 target, > bool mst, u8 link_nr, u8 > if (mst) > cmd |= NVDEF(NV0073_CTRL, DP_CMD, SET_FORMAT_MODE, > MULTI_STREAM); > > - if (outp->dp.dpcd[DPCD_RC02] & DPCD_RC02_ENHANCED_FRAME_CAP) > + if (nvkm_dp_enhanced_frame_cap(outp->dp.dpcd)) > cmd |= NVDEF(NV0073_CTRL, DP_CMD, SET_ENHANCED_FRAMING, TRUE); > > if (target == 0 && -- Jani Nikula, Intel
