On Thu, 2026-03-12 at 17:18 +0200, Imre Deak wrote:
> On Thu, Mar 12, 2026 at 10:05:35AM +0200, Hogander, Jouni wrote:
> > On Thu, 2026-03-12 at 10:30 +0530, Animesh Manna wrote:
> > > Unused bandwidth can be used by external display agents for Panel
> > > Replay
> > > enabled DP panel during idleness with link on. This patch series
> > > enabling the same.
> >
> > Generic comment on this patch set. Maybe we should add one more
> > patch
> > with "Fixes" tag:
> >
> > Fixes: e60cff453b82 ("drm/i915/dp: Enable DP tunnel BW allocation
> > mode")
> > Cc: Imre Deak <[email protected]>
> > Cc: <[email protected]> # v6.9+
>
> Why? As I understand the Panel Replay BW optimization on a DP
> tunneled
> link is an _optional_ feature, whereby the free BW can be used by the
> Thunderbolt protocol for other purposes than for the given display
> stream for which Panel Replay is enabled. IOW, it looks to me a valid
> configuration to enable Panel Replay on a DP tunneled link without
> enabling the Panel Replay BW optimization on it.
My original comment was about DP spec:
"
The DP Source device may optionally enable PR optimization with DP
tunneling. The device
shall query the Tunneling Bridge’s PR tunneling optimization capability
by way of the
Panel_Replay_Tunneling_Optimization_Support bit in the
DP_TUNNELING_CAPABILITIES
register (DPCD E000Dh[6]), and then enable PR only when the Tunneling
Bridge is capable.
"
That sounds like PR can be enabled only when Panel Replay Tunneling
Optimization is supported?
BR,
Jouni Högander
>
> > This patch would just add:
> >
> > if (intel_dp_tunnel_bw_alloc_is_enabled(intel_dp)) {
> > drm_dbg_kms(display->drm,
> > "Panel Replay is disabled as DP tunneling
> > enabled\n");
> > return false;
> > }
> >
> > into _panel_replay_compute_config. this could be first patch in
> > your
> > set. What do you think?
> >
> > BR,
> > Jouni Högander
> >
> > >
> > > Signed-off-by: Animesh Manna <[email protected]>
> > >
> > > Animesh Manna (3):
> > > drm/i915/display: Add drm helper to check pr optimization
> > > support
> > > drm/i915/display: Panel Replay BW optimization for DP2.0
> > > tunneling
> > > drm/i915/display: Disable Panel Replay for DP-tunneling without
> > > optimization
> > >
> > > drivers/gpu/drm/display/drm_dp_tunnel.c | 17 ++++++++++
> > > .../gpu/drm/i915/display/intel_display_regs.h | 1 +
> > > .../gpu/drm/i915/display/intel_dp_tunnel.c | 14 +++++++++
> > > .../gpu/drm/i915/display/intel_dp_tunnel.h | 6 ++++
> > > drivers/gpu/drm/i915/display/intel_psr.c | 31
> > > +++++++++++++++++--
> > > include/drm/display/drm_dp_tunnel.h | 6 ++++
> > > 6 files changed, 73 insertions(+), 2 deletions(-)
> > >
> >
