From: Alex Deucher alexander.deucher@amd.com
commit 5c458585c0141754cdcbf25feebb547dd671b559 upstream.
Commit 098214999c8f added fetching of the AUX_DPHY register values from the vbios, but it also changed the default values in the case when there are no values in the vbios. This causes problems with displays with high refresh rates. To fix this, switch back to the original default value for AUX_DPHY_TX_CONTROL.
Fixes: 098214999c8f ("drm/amd/display: Read VBIOS Golden Settings Tbl") Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1426 Reviewed-by: Harry Wentland harry.wentland@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: Igor Kravchenko Igor.Kravchenko@amd.com Cc: Aric Cyr Aric.Cyr@amd.com Cc: Aurabindo Pillai aurabindo.pillai@amd.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/dc/dcn20/dcn20_link_encoder.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_link_encoder.c +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_link_encoder.c @@ -341,8 +341,7 @@ void enc2_hw_init(struct link_encoder *e } else { AUX_REG_WRITE(AUX_DPHY_RX_CONTROL0, 0x103d1110);
- AUX_REG_WRITE(AUX_DPHY_TX_CONTROL, 0x21c4d); - + AUX_REG_WRITE(AUX_DPHY_TX_CONTROL, 0x21c7a); }
//AUX_DPHY_TX_REF_CONTROL'AUX_TX_REF_DIV HW default is 0x32;