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

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

[gregkh]

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 <stable@vger.kernel.org> know about it.


>From 2ba8d1bb8f6b589037f7db1f01144fc80750e8f7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= <jglisse@redhat.com>
Date: Fri, 19 Jun 2015 10:32:16 -0400
Subject: drm/radeon: SDMA fix hibernation (CI GPU family).
MIME-Version: 1.0
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From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= <jglisse@redhat.com>

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

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

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

--- a/drivers/gpu/drm/radeon/cik_sdma.c
+++ b/drivers/gpu/drm/radeon/cik_sdma.c
@@ -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 jglisse@redhat.com 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