From: Alex Deucher <alexander.deucher@amd.com>
Date: Tue, 3 Mar 2015 01:41:31 +0000 (-0500)
Subject: drm/radeon: do a posting read in r600_set_irq
X-Git-Tag: android-x86-4.4-r3~201^2~3^2~5
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=9d1393f23d5656cdd5f368efd60694d4aeed81d3;p=android-x86%2Fkernel.git

drm/radeon: do a posting read in r600_set_irq

To make sure the writes go through the pci bridge.

bug:
https://bugzilla.kernel.org/show_bug.cgi?id=90741

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
---

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 07a71a2488c9..2fcad344492f 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -3784,6 +3784,9 @@ int r600_irq_set(struct radeon_device *rdev)
 		WREG32(RV770_CG_THERMAL_INT, thermal_int);
 	}
 
+	/* posting read */
+	RREG32(R_000E50_SRBM_STATUS);
+
 	return 0;
 }