From: Alex Deucher <alexander.deucher@amd.com>
Date: Tue, 3 Mar 2015 01:42:53 +0000 (-0500)
Subject: drm/radeon: do a posting read in evergreen_set_irq
X-Git-Tag: firefly_0821_release~3679^2~670
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c1f447877ae10c0185be9823db482b324b061a9e;p=firefly-linux-kernel-4.4.55.git

drm/radeon: do a posting read in evergreen_set_irq

commit c320bb5f6dc0cb88a811cbaf839303e0a3916a92 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/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index ead08a49bec0..59ea6547306b 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -4016,6 +4016,9 @@ int evergreen_irq_set(struct radeon_device *rdev)
 	WREG32(AFMT_AUDIO_PACKET_CONTROL + EVERGREEN_CRTC4_REGISTER_OFFSET, afmt5);
 	WREG32(AFMT_AUDIO_PACKET_CONTROL + EVERGREEN_CRTC5_REGISTER_OFFSET, afmt6);
 
+	/* posting read */
+	RREG32(SRBM_STATUS);
+
 	return 0;
 }