[Intel-gfx] [PATCH v2 13/21] drm/i915/mtl: For DP2.0 10G and 20G rates use MPLLA

[Mika Kahola <mika.kahola@intel.com>]

Use MPLLA for DP2.0 rates 20G and 20G, when ssc is enabled.

Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221014124740.774835-14-mika.kahola@intel.com
---
 drivers/gpu/drm/i915/display/intel_cx0_phy.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_cx0_phy.c b/drivers/gpu/drm/i915/display/intel_cx0_phy.c
index 7520f50d4ffc..67e8889aec29 100644
--- a/drivers/gpu/drm/i915/display/intel_cx0_phy.c
+++ b/drivers/gpu/drm/i915/display/intel_cx0_phy.c
@@ -2128,8 +2128,12 @@ static void intel_program_port_clock_ctl(struct intel_encoder *encoder,
 		if (!intel_panel_use_ssc(i915))
 			ssc_enabled = false;
 
-		/* TODO: DP2.0 10G and 20G rates enable MPLLA*/
-		val |= ssc_enabled ? XELPDP_SSC_ENABLE_PLLB : 0;
+		/* DP2.0 10G and 20G rates enable MPLLA*/
+		if (crtc_state->port_clock == 1000000 || crtc_state->port_clock == 2000000) {
+			val |= ssc_enabled ? XELPDP_SSC_ENABLE_PLLA : 0;
+		} else {
+			val |= ssc_enabled ? XELPDP_SSC_ENABLE_PLLB : 0;
+		}
 	}
 
 	intel_de_rmw(i915, XELPDP_PORT_CLOCK_CTL(encoder->port),
-- 
2.34.1