drm/amd/display: Enable Freesync over PCon

[why]
Enable Freesync over PCon on Linux environment.

[how]
Adding Freesync over PCon support in amdgpu_dm
- Read DPCD for Freesync over PCon capabilitiy
- Add whitelist for compatible branch devices

Reviewed-by: Chao-kai Wang <Stylon.Wang@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Sung Joon Kim <sungkim@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index a50319fc42b1..5c733d445fe9 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -1133,3 +1133,36 @@ void dm_helpers_dp_mst_update_branch_bandwidth(
 	// TODO
 }
 
+static bool dm_is_freesync_pcon_whitelist(const uint32_t branch_dev_id)
+{
+	bool ret_val = false;
+
+	switch (branch_dev_id) {
+	case DP_BRANCH_DEVICE_ID_0060AD:
+		ret_val = true;
+		break;
+	default:
+		break;
+	}
+
+	return ret_val;
+}
+
+enum adaptive_sync_type dm_get_adaptive_sync_support_type(struct dc_link *link)
+{
+	struct dpcd_caps *dpcd_caps = &link->dpcd_caps;
+	enum adaptive_sync_type as_type = ADAPTIVE_SYNC_TYPE_NONE;
+
+	switch (dpcd_caps->dongle_type) {
+	case DISPLAY_DONGLE_DP_HDMI_CONVERTER:
+		if (dpcd_caps->adaptive_sync_caps.dp_adap_sync_caps.bits.ADAPTIVE_SYNC_SDP_SUPPORT == true &&
+			dpcd_caps->allow_invalid_MSA_timing_param == true &&
+			dm_is_freesync_pcon_whitelist(dpcd_caps->branch_dev_id))
+			as_type = FREESYNC_TYPE_PCON_IN_WHITELIST;
+		break;
+	default:
+		break;
+	}
+
+	return as_type;
+}