drm/i915/xe2hpd: Set maximum DP rate to UHBR13.5

Max supported speed by xe2hpd is UHBR13.5. Limit the max DP source rate
to it.

Bspec: 67066
Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Reviewed-by: Shekhar Chauhan <shekhar.chauhan@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240430172850.1881525-16-radhakrishna.sripada@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index e05e25cd4a9400f915131f05d31b43b41330e357..486361eb007054c5fda7f366835d3bb58379a02c 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -477,6 +477,9 @@ static int mtl_max_source_rate(struct intel_dp *intel_dp)
        if (intel_encoder_is_c10phy(encoder))
                return 810000;
 
+       if (DISPLAY_VER_FULL(to_i915(encoder->base.dev)) == IP_VER(14, 1))
+               return 1350000;
+
        return 2000000;
 }