From: Peichen Huang <peichen.huang@xxxxxxx> commit 7c5835bcb9176df94683396f1c0e5df6bf5094b3 upstream. [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@xxxxxxx> Cc: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Acked-by: Stylon Wang <stylon.wang@xxxxxxx> Signed-off-by: Peichen Huang <peichen.huang@xxxxxxx> Reviewed-by: Mustapha Ghaddar <Mustapha.Ghaddar@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/amd/display/dc/link/link_detection.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/gpu/drm/amd/display/dc/link/link_detection.c +++ b/drivers/gpu/drm/amd/display/dc/link/link_detection.c @@ -980,6 +980,11 @@ static bool detect_link_and_local_sink(s (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; }
