drm/i915/mtl: Support HBR3 rate with C10 phy and eDP in MTL

eDP specification supports HBR3 link rate since v1.4a. Moreover,
C10 phy can support HBR3 link rate for both DP and eDP. Therefore,
do not clamp the supported rates for eDP at 6.75Gbps.

Cc: <stable@vger.kernel.org>
BSpec: 70073 74224

Signed-off-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231018113622.2761997-1-chaitanya.kumar.borah@intel.com
(cherry picked from commit a3431650f30a94b179d419ef87c21213655c28cd)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 1891c0cc187d11ba06067be512ba302dc0e87e43..2c103457898407701c25a9403a4238e5a6a93d9c 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -430,7 +430,7 @@ static int mtl_max_source_rate(struct intel_dp *intel_dp)
        enum phy phy = intel_port_to_phy(i915, dig_port->base.port);
 
        if (intel_is_c10phy(i915, phy))
-               return intel_dp_is_edp(intel_dp) ? 675000 : 810000;
+               return 810000;
 
        return 2000000;
 }