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: firefly_0821_release~176^2~2198^2~3^2~3
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0586915ec10d0ae60de5cd3381ad25a704760402;p=firefly-linux-kernel-4.4.55.git

drm/radeon: do a posting read in si_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/si.c b/drivers/gpu/drm/radeon/si.c
index bcf516a8a2f1..e088e5558da0 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -6203,6 +6203,9 @@ int si_irq_set(struct radeon_device *rdev)
 
 	WREG32(CG_THERMAL_INT, thermal_int);
 
+	/* posting read */
+	RREG32(SRBM_STATUS);
+
 	return 0;
 }