[3.5.y.z extended stable] Patch "drm/radeon: Fix sideport problems on certain RS690 boards" has been added to staging queue

[Luis Henriques]

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

    drm/radeon: Fix sideport problems on certain RS690 boards

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

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

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
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 63df6cdd545dd5a597c97e15cf808b669255d51d Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher at amd.com>
Date: Mon, 2 Dec 2013 18:15:51 -0500
Subject: drm/radeon: Fix sideport problems on certain RS690 boards

commit 8333f0fe133be420ce3fcddfd568c3a559ab274e upstream.

Some RS690 boards with 64MB of sideport memory show up as
having 128MB sideport + 256MB of UMA.  In this case,
just skip the sideport memory and use UMA.  This fixes
rendering corruption and should improve performance.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=35457

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
[ luis: backported to 3.5: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/gpu/drm/radeon/rs690.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/radeon/rs690.c b/drivers/gpu/drm/radeon/rs690.c
index bcfb0a3..024ceeb 100644
--- a/drivers/gpu/drm/radeon/rs690.c
+++ b/drivers/gpu/drm/radeon/rs690.c
@@ -160,6 +160,17 @@ void rs690_mc_init(struct radeon_device *rdev)
 	base = RREG32_MC(R_000100_MCCFG_FB_LOCATION);
 	base = G_000100_MC_FB_START(base) << 16;
 	rdev->mc.igp_sideport_enabled = radeon_atombios_sideport_present(rdev);
+	/* Some boards seem to be configured for 128MB of sideport memory,
+	 * but really only have 64MB.  Just skip the sideport and use
+	 * UMA memory.
+	 */
+	if (rdev->mc.igp_sideport_enabled &&
+	    (rdev->mc.real_vram_size == (384 * 1024 * 1024))) {
+		base += 128 * 1024 * 1024;
+		rdev->mc.real_vram_size -= 128 * 1024 * 1024;
+		rdev->mc.mc_vram_size = rdev->mc.real_vram_size;
+	}
+
 	rs690_pm_info(rdev);
 	radeon_vram_location(rdev, &rdev->mc, base);
 	rdev->mc.gtt_base_align = rdev->mc.gtt_size - 1;
--
1.8.3.2