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: v5.15~16202^2~3^2~4
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c320bb5f6dc0cb88a811cbaf839303e0a3916a92;p=platform%2Fkernel%2Flinux-starfive.git

drm/radeon: do a posting read in evergreen_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/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index 4c0e24b..973df06 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -4593,6 +4593,9 @@ 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;
 }