6.12-stable review patch. If anyone has any objections, please let me know.
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From: Imre Deak imre.deak@intel.com
commit 166ce267ae3f96e439d8ccc838e8ec4d8b4dab73 upstream.
Fix the port width programming in the DDI_BUF_CTL register on MTLP+, where this had an off-by-one error.
Cc: stable@vger.kernel.org # 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@intel.com Signed-off-by: Imre Deak imre.deak@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20250214142001.552916-3-imre.d... (cherry picked from commit b2ecdabe46d23db275f94cd7c46ca414a144818b) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/display/intel_ddi.c | 2 +- drivers/gpu/drm/i915/i915_reg.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/i915/display/intel_ddi.c +++ b/drivers/gpu/drm/i915/display/intel_ddi.c @@ -3363,7 +3363,7 @@ static void intel_enable_ddi_hdmi(struct intel_de_rmw(dev_priv, XELPDP_PORT_BUF_CTL1(dev_priv, 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; --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -3869,7 +3869,7 @@ 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)