From 50dae5bab56e25458a53b4869434789e29517034 Mon Sep 17 00:00:00 2001 From: Ankit Nautiyal Date: Tue, 15 Sep 2026 22:16:47 +0530 Subject: [PATCH] drm/i915/dip: Store and use AS SDP transmission line from crtc state The driver currently computes the Adaptive Sync SDP transmission line directly at programming time. Instead, compute and store the AS SDP transmission line in the crtc state and use it when programming the EMP_AS_SDP_TL register. We get the clear picture about the SDPs and guardband only in intel_dp_sdp_compute_config_late() therefore we must configure the AS SDP transmission line at this point when AS SDP is enabled in crtc_state. This prepares the ground for supporting programmable transmission lines for additional DP SDPs. While moving the helper into intel_dip.c, drop the intel_crtc_has_dp_encoder() check instead of relocating it. It was needed in the old VRR write path shared by other encoderes as well, but intel_dip_sdp_tl_compute_config_late() is only reached via DP, so HDMI never sets crtc_state->dip.emp_as_sdp_tl and it stays 0 by default. v2: - Move the helper into intel_dip.c and drop the intel_crtc_has_dp_encoder() check. - Drop the redundant checks. (Suraj) Signed-off-by: Ankit Nautiyal Reviewed-by: Suraj Kandpal Link: https://patch.msgid.link/20260915164657.3429075-7-ankit.k.nautiyal@intel.com --- drivers/gpu/drm/i915/display/intel_ddi.c | 2 ++ drivers/gpu/drm/i915/display/intel_dip.c | 20 +++++++++++--------- drivers/gpu/drm/i915/display/intel_dip.h | 3 +++ drivers/gpu/drm/i915/display/intel_dp.c | 3 +++ 4 files changed, 19 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c index 9b3b526e5e55..dacb4b7588a0 100644 --- a/drivers/gpu/drm/i915/display/intel_ddi.c +++ b/drivers/gpu/drm/i915/display/intel_ddi.c @@ -49,6 +49,7 @@ #include "intel_ddi.h" #include "intel_ddi_buf_trans.h" #include "intel_de.h" +#include "intel_dip.h" #include "intel_display_power.h" #include "intel_display_regs.h" #include "intel_display_types.h" @@ -4235,6 +4236,7 @@ static void intel_ddi_get_config(struct intel_encoder *encoder, intel_read_dp_sdp(encoder, pipe_config, HDMI_PACKET_TYPE_GAMUT_METADATA); intel_read_dp_sdp(encoder, pipe_config, DP_SDP_VSC); intel_read_dp_sdp(encoder, pipe_config, DP_SDP_ADAPTIVE_SYNC); + intel_dip_sdp_transmission_line_get_config(pipe_config); intel_audio_codec_get_config(encoder, pipe_config); } diff --git a/drivers/gpu/drm/i915/display/intel_dip.c b/drivers/gpu/drm/i915/display/intel_dip.c index 0277b15e1c82..d1acc7eb5a39 100644 --- a/drivers/gpu/drm/i915/display/intel_dip.c +++ b/drivers/gpu/drm/i915/display/intel_dip.c @@ -43,19 +43,21 @@ void intel_dip_write_emp_as_sdp_tl(const struct intel_crtc_state *crtc_state) { struct intel_display *display = to_intel_display(crtc_state); enum transcoder cpu_transcoder = crtc_state->cpu_transcoder; - u32 transmission_line = 0; if (!HAS_EMP_AS_SDP_TL(display)) return; - /* - * Since we currently support VRR only for DP/eDP, program the register - * for Adaptive Sync SDP using vsync start. For non-DP encoders, - * the register is reset to 0. - */ - if (intel_crtc_has_dp_encoder(crtc_state)) - transmission_line = intel_dip_get_as_sdp_transmission_line(crtc_state); intel_de_write(display, EMP_AS_SDP_TL(display, cpu_transcoder), - EMP_AS_SDP_DB_TL(transmission_line)); + EMP_AS_SDP_DB_TL(crtc_state->dip.emp_as_sdp_tl)); +} + +void intel_dip_sdp_tl_compute_config_late(struct intel_crtc_state *crtc_state) +{ + crtc_state->dip.emp_as_sdp_tl = intel_dip_get_as_sdp_transmission_line(crtc_state); +} + +void intel_dip_sdp_transmission_line_get_config(struct intel_crtc_state *crtc_state) +{ + crtc_state->dip.emp_as_sdp_tl = intel_dip_read_emp_as_sdp_tl(crtc_state); } diff --git a/drivers/gpu/drm/i915/display/intel_dip.h b/drivers/gpu/drm/i915/display/intel_dip.h index 25bae4a04d6b..20f9aeb85c39 100644 --- a/drivers/gpu/drm/i915/display/intel_dip.h +++ b/drivers/gpu/drm/i915/display/intel_dip.h @@ -35,4 +35,7 @@ struct intel_crtc_state; u16 intel_dip_read_emp_as_sdp_tl(const struct intel_crtc_state *crtc_state); void intel_dip_write_emp_as_sdp_tl(const struct intel_crtc_state *crtc_state); +void intel_dip_sdp_tl_compute_config_late(struct intel_crtc_state *crtc_state); +void intel_dip_sdp_transmission_line_get_config(struct intel_crtc_state *crtc_state); + #endif /* __INTEL_DIP_H__ */ diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index c44d584cc07a..f55ae30bebf8 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -61,6 +61,7 @@ #include "intel_cx0_phy.h" #include "intel_ddi.h" #include "intel_de.h" +#include "intel_dip.h" #include "intel_display_driver.h" #include "intel_display_jiffies.h" #include "intel_display_utils.h" @@ -7362,6 +7363,8 @@ int intel_dp_sdp_compute_config_late(struct intel_crtc_state *crtc_state) return -EINVAL; } + intel_dip_sdp_tl_compute_config_late(crtc_state); + return 0; }