[PATCH 3.4 064/172] drm/radeon: do a posting read in r100_set_irq

lizf
2015-06-16T09:24:27Z

From: Alex Deucher <alexander.deucher@amd.com>

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

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

commit f957063fee6392bb9365370db6db74dc0b2dce0a 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: Zefan Li <lizefan@huawei.com>
---
drivers/gpu/drm/radeon/r100.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index 40ed0e5..8ec5b85 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -726,6 +726,10 @@ int r100_irq_set(struct radeon_device *rdev)
tmp |= RADEON_FP2_DETECT_MASK;
}
WREG32(RADEON_GEN_INT_CNTL, tmp);
+
+ /* read back to post the write */
+ RREG32(RADEON_GEN_INT_CNTL);
+
return 0;
}

--
1.9.1