From 68c31ce38baddfc69d4301f71edd02618c882aba Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michel=20D=C3=A4nzer?= <michel.daenzer@amd.com>
Date: Fri, 3 Jul 2015 10:02:27 +0900
Subject: [PATCH] drm/radeon: Don't flush the GART TLB if rdev->gart.ptr ==
NULL
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commit 233709d2cd6bbaaeda0aeb8d11f6ca7f98563b39 upstream.
This can be the case when the GPU is powered off, e.g. via vgaswitcheroo
or runpm. When the GPU is powered up again, radeon_gart_table_vram_pin
flushes the TLB after setting rdev->gart.ptr to non-NULL.
Fixes panic on powering off R7xx GPUs.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61529
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/radeon/radeon_gart.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/radeon/radeon_gart.c b/drivers/gpu/drm/radeon/radeon_gart.c
index a8f9b463bf2a..e60972290be6 100644
--- a/drivers/gpu/drm/radeon/radeon_gart.c
+++ b/drivers/gpu/drm/radeon/radeon_gart.c
@@ -251,8 +251,10 @@ void radeon_gart_unbind(struct radeon_device *rdev, unsigned offset,
}
}
}
- mb();
- radeon_gart_tlb_flush(rdev);
+ if (rdev->gart.ptr) {
+ mb();
+ radeon_gart_tlb_flush(rdev);
+ }
}
/**
@@ -294,8 +296,10 @@ int radeon_gart_bind(struct radeon_device *rdev, unsigned offset,
}
}
}
- mb();
- radeon_gart_tlb_flush(rdev);
+ if (rdev->gart.ptr) {
+ mb();
+ radeon_gart_tlb_flush(rdev);
+ }
return 0;
}
--
2.30.9