Patch "drm/amdgpu: Fix max_vblank_count value for current display engines" has been added to the 4.2-stable tree

Patch "drm/amdgpu: Fix max_vblank_count value for current display engines" has been added to the 4.2-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    drm/amdgpu: Fix max_vblank_count value for current display engines

to the 4.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-amdgpu-fix-max_vblank_count-value-for-current-display-engines.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 5a6adfa20b622a273205e33b20c12332aa7eb724 Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher@amd.com>
Date: Tue, 22 Sep 2015 10:06:45 -0400
Subject: drm/amdgpu: Fix max_vblank_count value for current display engines
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Alex Deucher <alexander.deucher@amd.com>

commit 5a6adfa20b622a273205e33b20c12332aa7eb724 upstream.

The value was much too low, which could cause the userspace visible
vblank counter to move backwards when the hardware counter wrapped
around.

Ported from radeon commit:
b0b9bb4dd51f396dcf843831905f729e74b0c8c0

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c
@@ -140,7 +140,7 @@ void amdgpu_irq_preinstall(struct drm_de
  */
 int amdgpu_irq_postinstall(struct drm_device *dev)
 {
-	dev->max_vblank_count = 0x001fffff;
+	dev->max_vblank_count = 0x00ffffff;
 	return 0;
 }
 


Patches currently in stable-queue which might be from alexander.deucher@amd.com are

queue-4.2/drm-amdgpu-restore-lcd-backlight-level-on-resume.patch
queue-4.2/drm-amdgpu-fix-max_vblank_count-value-for-current-display-engines.patch