From: Alex Deucher <alexander.deucher@amd.com>
Date: Tue, 3 Mar 2015 01:45:24 +0000 (-0500)
Subject: drm/radeon: do a posting read in cik_set_irq
X-Git-Tag: v3.12.40~127
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4ca1ac7997dbc13b8de4448f9e7e7b6d07cac3fa;p=thirdparty%2Fkernel%2Fstable.git

drm/radeon: do a posting read in cik_set_irq

commit cffefd9bb31cd35ab745d3b49005d10616d25bdc upstream.

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>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---

diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index 6e2e4a859047d..bb4c6573a525f 100644
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -6352,6 +6352,9 @@ int cik_irq_set(struct radeon_device *rdev)
 	WREG32(DC_HPD5_INT_CONTROL, hpd5);
 	WREG32(DC_HPD6_INT_CONTROL, hpd6);
 
+	/* posting read */
+	RREG32(SRBM_STATUS);
+
 	return 0;
 }