[ 3.5.y.z extended stable ] Patch "drm/radeon/evergreen+: wait for the MC to settle after MC" has been added to staging queue

Herton Ronaldo Krzesinski herton.krzesinski at canonical.com
Tue Feb 12 21:18:32 UTC 2013

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

    drm/radeon/evergreen+: wait for the MC to settle after MC

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:


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

For more information about the 3.5.y.z tree, see



>From 93fe7ed2644e75056a2a6d9ffaab2ddba3ddfd26 Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher at amd.com>
Date: Thu, 31 Jan 2013 09:00:52 -0500
Subject: [PATCH] drm/radeon/evergreen+: wait for the MC to settle after MC

commit ed39fadd6df01095378e499fac3674883f16b853 upstream.

Some chips seem to need a little delay after blacking out
the MC before the requests actually stop.

May fix:

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
 drivers/gpu/drm/radeon/evergreen.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index 4170e1e..ccac010 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -1183,6 +1183,8 @@ void evergreen_mc_stop(struct radeon_device *rdev, struct evergreen_mc_save *sav
 		blackout &= ~BLACKOUT_MODE_MASK;
 		WREG32(MC_SHARED_BLACKOUT_CNTL, blackout | 1);
+	/* wait for the MC to settle */
+	udelay(100);

 void evergreen_mc_resume(struct radeon_device *rdev, struct evergreen_mc_save *save)

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