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-Url: http://git.mmlx.us/?a=commitdiff_plain;h=693fcdbda7ecc657abb6e83d306c7c43c4b766bc;p=linux-edison.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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index 03add5d5542..87dbbb65769 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -5778,5 +5778,8 @@ int si_set_uvd_clocks(struct radeon_device *rdev, u32 vclk, u32 dclk)
 
 	mdelay(100);
 
+	/* posting read */
+	RREG32(SRBM_STATUS);
+
 	return 0;
 }