drm/radeon/kms/atom: fix duallink on some early DCE3.2 cards

Certain revisions of the vbios on DCE3.2 cards have a bug in the transmitter control table which prevents duallink from being enabled properly on some cards. The action switch statement jumps to the wrong offset for the OUTPUT_ENABLE action. The fix is to use the ENABLE action rather than the OUTPUT_ENABLE action on the affected cards. In fixed version of the vbios, both actions jump to the same offset, so the change should be safe. Reported-and-tested-by: Dave Airlie <[email protected]> Signed-off-by: Alex Deucher <[email protected]> Cc: [email protected] Signed-off-by: Dave Airlie <[email protected]>
mna · Jun 19, 2011 · 8323fa6 · 8323fa6
1 parent de505e7
commit 8323fa6
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/drivers/gpu/drm/radeon/radeon_encoders.c b/drivers/gpu/drm/radeon/radeon_encoders.c
@@ -1431,7 +1431,11 @@ radeon_atom_encoder_dpms(struct drm_encoder *encoder, int mode)
 	if (is_dig) {
 		switch (mode) {
 		case DRM_MODE_DPMS_ON:
-			atombios_dig_transmitter_setup(encoder, ATOM_TRANSMITTER_ACTION_ENABLE_OUTPUT, 0, 0);
+			/* some early dce3.2 boards have a bug in their transmitter control table */
+			if ((rdev->family == CHIP_RV710) || (rdev->family == CHIP_RV730))
+				atombios_dig_transmitter_setup(encoder, ATOM_TRANSMITTER_ACTION_ENABLE, 0, 0);
+			else
+				atombios_dig_transmitter_setup(encoder, ATOM_TRANSMITTER_ACTION_ENABLE_OUTPUT, 0, 0);
 			if (atombios_get_encoder_mode(encoder) == ATOM_ENCODER_MODE_DP) {
 				struct drm_connector *connector = radeon_get_connector_for_encoder(encoder);