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

commit ce4941c2d6459664761c9854701015d8e99414fb upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index cb55112d6065742af78028133ca26177c1cee109..ec28354efc1c3dd733b3c94d6d70a5fe2ac7ced5 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;
 }