From: Alex Deucher <alexander.deucher@amd.com>
Date: Tue, 3 Mar 2015 01:43:53 +0000 (-0500)
Subject: drm/radeon: do a posting read in si_set_irq
X-Git-Tag: v3.16.35~2567
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7fd688396709086144058dba4056751a830610c5;p=thirdparty%2Fkernel%2Fstable.git

drm/radeon: do a posting read in si_set_irq

commit 0586915ec10d0ae60de5cd3381ad25a704760402 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/si.c b/drivers/gpu/drm/radeon/si.c
index 23d0bbb64db57..74f41809bb42b 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -5972,6 +5972,9 @@ int si_irq_set(struct radeon_device *rdev)
 
 	WREG32(CG_THERMAL_INT, thermal_int);
 
+	/* posting read */
+	RREG32(SRBM_STATUS);
+
 	return 0;
 }