[PATCH 6.1.y] drm/amd/display: limit DPIA link rate to HBR3

[Mario Limonciello <mario.limonciello@amd.com>]

From: Peichen Huang <peichen.huang@amd.com>

[Why]
DPIA doesn't support UHBR, driver should not enable UHBR
for dp tunneling

[How]
limit DPIA link rate to HBR3

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Acked-by: Stylon Wang <stylon.wang@amd.com>
Signed-off-by: Peichen Huang <peichen.huang@amd.com>
Reviewed-by: Mustapha Ghaddar <Mustapha.Ghaddar@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 0e69ef6ea82e8eece7d2b2b45a0da9670eaaefff)
This was CC to stable, but failed to apply because the file was
renamed in 6.3-rc1 as part of
54618888d1ea ("drm/amd/display: break down dc_link.c")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index 5d53e54ebe90..63daf6ecbda7 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -1141,6 +1141,11 @@ static bool detect_link_and_local_sink(struct dc_link *link,
 					(link->dpcd_caps.dongle_type !=
 							DISPLAY_DONGLE_DP_HDMI_CONVERTER))
 				converter_disable_audio = true;
+
+			/* limited link rate to HBR3 for DPIA until we implement USB4 V2 */
+			if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA &&
+					link->reported_link_cap.link_rate > LINK_RATE_HIGH3)
+				link->reported_link_cap.link_rate = LINK_RATE_HIGH3;
 			break;
 		}
 
-- 
2.34.1