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: v3.16.35~2566
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=ed9becce235215bd152156c1ba2e126d115061c0;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: Luis Henriques <luis.henriques@canonical.com>
---

diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index f898ed31cffb3..574d1f4ec7e51 100644
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -7185,6 +7185,9 @@ 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;
 }