Patch "drm/radeon: SDMA fix hibernation (CI GPU family)." has been added to the 3.14-stable tree

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

drm/radeon: SDMA fix hibernation (CI GPU family).

to the 3.14-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-radeon-sdma-fix-hibernation-ci-gpu-family.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= <[email protected]>
Date: Fri, 19 Jun 2015 10:32:16 -0400
Subject: drm/radeon: SDMA fix hibernation (CI GPU family).
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From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= <[email protected]>

commit 2ba8d1bb8f6b589037f7db1f01144fc80750e8f7 upstream.

In order for hibernation to reliably work we need to properly turn off the SDMA block, sadly after numerous attemps i haven't not found proper sequence for clean and full shutdown. So simply reset both SDMA block, this makes hibernation works reliably on sea island GPU family (CI)

Hibernation and suspend to ram were tested (several times) on :
Bonaire
Hawaii
Mullins
Kaveri
Kabini

---
 drivers/gpu/drm/radeon/cik_sdma.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

@@ -266,6 +266,17 @@ static void cik_sdma_gfx_stop(struct rad
 	}
 	rdev->ring[R600_RING_TYPE_DMA_INDEX].ready = false;
 	rdev->ring[CAYMAN_RING_TYPE_DMA1_INDEX].ready = false;
+
+	/* FIXME use something else than big hammer but after few days can not
+	 * seem to find good combination so reset SDMA blocks as it seems we
+	 * do not shut them down properly. This fix hibernation and does not
+	 * affect suspend to ram.
+	 */
+	WREG32(SRBM_SOFT_RESET, SOFT_RESET_SDMA | SOFT_RESET_SDMA1);
+	(void)RREG32(SRBM_SOFT_RESET);
+	udelay(50);
+	WREG32(SRBM_SOFT_RESET, 0);
+	(void)RREG32(SRBM_SOFT_RESET);
 }
 
 /**

Patches currently in stable-queue which might be from [email protected] are

queue-3.14/drm-radeon-compute-ring-fix-hibernation-ci-gpu-family-v2.patch queue-3.14/drm-radeon-sdma-fix-hibernation-ci-gpu-family.patch