[PATCH 3.4 066/172] drm/radeon: do a posting read in r600_set_irq

From: lizf
Date: Tue Jun 16 2015 - 05:24:17 EST


From: Alex Deucher <alexander.deucher@xxxxxxx>

3.4.108-rc1 review patch. If anyone has any objections, please let me know.

------------------


commit 9d1393f23d5656cdd5f368efd60694d4aeed81d3 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@xxxxxxx>
Signed-off-by: Zefan Li <lizefan@xxxxxxxxxx>
---
drivers/gpu/drm/radeon/r600.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 1555cd6..9c7062d 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -3184,6 +3184,9 @@ int r600_irq_set(struct radeon_device *rdev)
WREG32(DC_HOT_PLUG_DETECT3_INT_CONTROL, hpd3);
}

+ /* posting read */
+ RREG32(R_000E50_SRBM_STATUS);
+
return 0;
}

--
1.9.1

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