[3.16.y-ckt stable] Patch "drm/radeon: Don't drop DP 2.7 Ghz link setup on some cards." has been added to the 3.16.y-ckt tree

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    drm/radeon: Don't drop DP 2.7 Ghz link setup on some cards.

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt27.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

---8<------------------------------------------------------------

>From 3ca97ceb7f6e21133b2b0156a7a78ed15455659a Mon Sep 17 00:00:00 2001
From: Mario Kleiner <mario.kleiner.de at gmail.com>
Date: Sun, 6 Mar 2016 02:39:53 +0100
Subject: drm/radeon: Don't drop DP 2.7 Ghz link setup on some cards.

commit 459ee1c3fd097ab56ababd8ff4bb7ef6a792de33 upstream.

As observed on Apple iMac10,1, DCE-3.2, RV-730,
link rate of 2.7 Ghz is not selected, because
the args.v1.ucConfig flag setting for 2.7 Ghz
gets overwritten by a following assignment of
the transmitter to use.

Move link rate setup a few lines down to fix this.
In practice this didn't have any positive or
negative effect on display setup on the tested
iMac10,1 so i don't know if backporting to stable
makes sense or not.

Signed-off-by: Mario Kleiner <mario.kleiner.de at gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/gpu/drm/radeon/atombios_encoders.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c
index 7961b80b6a78..f74f3d59978b 100644
--- a/drivers/gpu/drm/radeon/atombios_encoders.c
+++ b/drivers/gpu/drm/radeon/atombios_encoders.c
@@ -896,8 +896,6 @@ atombios_dig_encoder_setup(struct drm_encoder *encoder, int action, int panel_mo
 			else
 				args.v1.ucLaneNum = 4;

-			if (ENCODER_MODE_IS_DP(args.v1.ucEncoderMode) && (dp_clock == 270000))
-				args.v1.ucConfig |= ATOM_ENCODER_CONFIG_DPLINKRATE_2_70GHZ;
 			switch (radeon_encoder->encoder_id) {
 			case ENCODER_OBJECT_ID_INTERNAL_UNIPHY:
 				args.v1.ucConfig = ATOM_ENCODER_CONFIG_V2_TRANSMITTER1;
@@ -914,6 +912,10 @@ atombios_dig_encoder_setup(struct drm_encoder *encoder, int action, int panel_mo
 				args.v1.ucConfig |= ATOM_ENCODER_CONFIG_LINKB;
 			else
 				args.v1.ucConfig |= ATOM_ENCODER_CONFIG_LINKA;
+
+			if (ENCODER_MODE_IS_DP(args.v1.ucEncoderMode) && (dp_clock == 270000))
+				args.v1.ucConfig |= ATOM_ENCODER_CONFIG_DPLINKRATE_2_70GHZ;
+
 			break;
 		case 2:
 		case 3: