From: Jouni Högander <jouni.hogander@intel.com>
Date: Thu, 23 Oct 2025 04:31:40 +0000 (+0300)
Subject: drm/i915/display: Take into account AS SDP in intel_dp_sdp_min_guardband
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=e69b7a6bd4ea813282956873b63f8215f73ed966;p=thirdparty%2Fkernel%2Flinux.git

drm/i915/display: Take into account AS SDP in intel_dp_sdp_min_guardband

We started seeing "[drm] *ERROR* Timed out waiting PSR idle state" after
taking optimized guardband into use. These are seen because VSC SDPs are
sent on same line as AS SDPs when AS SDP is enabled. AS SDP is sent on line
configured in EMP_AS_SDP_TL register. We are configuring
crtc_state->vrr.vsync_start into that register.

Fix this by ensuring AS SDP is sent on line which is within
guardband. From the bspec:

EMP_AS_SDP_TL < SCL + Guardband

v2: check HAS_AS_SDP

Bspec: 71197
Fixes: 52ecd48b8d3f ("drm/i915/dp: Add helper to get min sdp guardband")
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://lore.kernel.org/r/20251023043140.961104-1-jouni.hogander@intel.com
---

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 475518b4048b7..a3391b17571cf 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -7023,7 +7023,7 @@ int intel_dp_compute_config_late(struct intel_encoder *encoder,
 }
 
 static
-int intel_dp_get_lines_for_sdp(u32 type)
+int intel_dp_get_lines_for_sdp(const struct intel_crtc_state *crtc_state, u32 type)
 {
 	switch (type) {
 	case DP_SDP_VSC_EXT_VESA:
@@ -7033,6 +7033,8 @@ int intel_dp_get_lines_for_sdp(u32 type)
 		return 8;
 	case DP_SDP_PPS:
 		return 7;
+	case DP_SDP_ADAPTIVE_SYNC:
+		return crtc_state->vrr.vsync_start + 1;
 	default:
 		break;
 	}
@@ -7043,17 +7045,25 @@ int intel_dp_get_lines_for_sdp(u32 type)
 int intel_dp_sdp_min_guardband(const struct intel_crtc_state *crtc_state,
 			       bool assume_all_enabled)
 {
+	struct intel_display *display = to_intel_display(crtc_state);
 	int sdp_guardband = 0;
 
 	if (assume_all_enabled ||
 	    crtc_state->infoframes.enable &
 	    intel_hdmi_infoframe_enable(HDMI_PACKET_TYPE_GAMUT_METADATA))
 		sdp_guardband = max(sdp_guardband,
-				    intel_dp_get_lines_for_sdp(HDMI_PACKET_TYPE_GAMUT_METADATA));
+				    intel_dp_get_lines_for_sdp(crtc_state,
+							       HDMI_PACKET_TYPE_GAMUT_METADATA));
 
 	if (assume_all_enabled ||
 	    crtc_state->dsc.compression_enable)
-		sdp_guardband = max(sdp_guardband, intel_dp_get_lines_for_sdp(DP_SDP_PPS));
+		sdp_guardband = max(sdp_guardband,
+				    intel_dp_get_lines_for_sdp(crtc_state, DP_SDP_PPS));
+
+	if ((assume_all_enabled && HAS_AS_SDP(display)) ||
+	    crtc_state->infoframes.enable & intel_hdmi_infoframe_enable(DP_SDP_ADAPTIVE_SYNC))
+		sdp_guardband = max(sdp_guardband,
+				    intel_dp_get_lines_for_sdp(crtc_state, DP_SDP_ADAPTIVE_SYNC));
 
 	return sdp_guardband;
 }