This is a note to let you know that I've just added the patch titled
drm/i915/ddi: Fix HDMI port width programming in DDI_BUF_CTL
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-i915-ddi-fix-hdmi-port-width-programming-in-ddi_.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a63388ee5efe4f6f0a252710d904b1cdf4bbef81
Author: Imre Deak <imre.deak@xxxxxxxxx>
Date: Fri Feb 14 16:19:52 2025 +0200
drm/i915/ddi: Fix HDMI port width programming in DDI_BUF_CTL
[ Upstream commit 166ce267ae3f96e439d8ccc838e8ec4d8b4dab73 ]
Fix the port width programming in the DDI_BUF_CTL register on MTLP+,
where this had an off-by-one error.
Cc: <stable@xxxxxxxxxxxxxxx> # v6.5+
Fixes: b66a8abaa48a ("drm/i915/display/mtl: Fill port width in DDI_BUF_/TRANS_DDI_FUNC_/PORT_BUF_CTL for HDMI")
Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20250214142001.552916-3-imre.deak@xxxxxxxxx
(cherry picked from commit b2ecdabe46d23db275f94cd7c46ca414a144818b)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index 9ac9df70e713c..893ecee3949ac 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -3242,7 +3242,7 @@ static void intel_enable_ddi_hdmi(struct intel_atomic_state *state,
intel_de_rmw(dev_priv, XELPDP_PORT_BUF_CTL1(port),
XELPDP_PORT_WIDTH_MASK | XELPDP_PORT_REVERSAL, port_buf);
- buf_ctl |= DDI_PORT_WIDTH(lane_count);
+ buf_ctl |= DDI_PORT_WIDTH(crtc_state->lane_count);
if (DISPLAY_VER(dev_priv) >= 20)
buf_ctl |= XE2LPD_DDI_BUF_D2D_LINK_ENABLE;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 4e588fd1c82ed..589a10253d898 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -5737,7 +5737,7 @@ enum skl_power_gate {
#define DDI_BUF_IS_IDLE (1 << 7)
#define DDI_BUF_CTL_TC_PHY_OWNERSHIP REG_BIT(6)
#define DDI_A_4_LANES (1 << 4)
-#define DDI_PORT_WIDTH(width) (((width) - 1) << 1)
+#define DDI_PORT_WIDTH(width) (((width) == 3 ? 4 : ((width) - 1)) << 1)
#define DDI_PORT_WIDTH_MASK (7 << 1)
#define DDI_PORT_WIDTH_SHIFT 1
#define DDI_INIT_DISPLAY_DETECTED (1 << 0)
