From: Mario Limonciello (AMD) Date: Mon, 3 Nov 2025 18:11:31 +0000 (-0600) Subject: drm/amd/display: Increase DPCD read retries X-Git-Tag: v6.18-rc7~18^2~1^2~9 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8612badc331bcab2068baefa69e1458085ed89e3;p=thirdparty%2Flinux.git drm/amd/display: Increase DPCD read retries [Why] Empirical measurement of some monitors that fail to read EDID while booting shows that the number of retries with a 30ms delay between tries is as high as 16. [How] Increase number of retries to 20. Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4672 Reviewed-by: Alex Hung Signed-off-by: Mario Limonciello (AMD) Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit ad1c59ad7cf74ec06e32fe2c330ac1e957222288) Cc: stable@vger.kernel.org --- diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c index 4d0079b44de1..eb262ce42e2d 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c @@ -1691,7 +1691,7 @@ static bool retrieve_link_cap(struct dc_link *link) union edp_configuration_cap edp_config_cap; union dp_downstream_port_present ds_port = { 0 }; enum dc_status status = DC_ERROR_UNEXPECTED; - uint32_t read_dpcd_retry_cnt = 3; + uint32_t read_dpcd_retry_cnt = 20; int i; struct dp_sink_hw_fw_revision dp_hw_fw_revision; const uint32_t post_oui_delay = 30; // 30ms