drm/radeon: do a posting read in si_set_irq

[ Upstream commit 0586915ec10d0ae60de5cd3381ad25a704760402 ]

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
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index 7d5083dc4acbad7d333766195586c3b5562a5f58..35ce05c78c4d6229ee6fb400eb794fe31377702d 100644 (file)
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -6192,6 +6192,9 @@ int si_irq_set(struct radeon_device *rdev)
 
        WREG32(CG_THERMAL_INT, thermal_int);
 
+       /* posting read */
+       RREG32(SRBM_STATUS);
+
        return 0;
 }