drm/radeon: disable MSI on RV515

BugLink: http://bugs.launchpad.net/bugs/987337

commit 16a5e32b83fd946312b9b13590c75d20c95c5202 upstream.

My rv515 card is very flaky with msi enabled. Every so often it loses a rearm
and never comes back, manually banging the rearm brings it back.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/drivers/gpu/drm/radeon/radeon_irq_kms.c b/drivers/gpu/drm/radeon/radeon_irq_kms.c
index e7ddb49..baa019e 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_irq_kms.c
+++ b/drivers/gpu/drm/radeon/radeon_irq_kms.c
@@ -143,6 +143,12 @@ static bool radeon_msi_ok(struct radeon_device *rdev)
            (rdev->pdev->subsystem_device == 0x01fd))
                return true;
 
+       /* RV515 seems to have MSI issues where it loses
+        * MSI rearms occasionally. This leads to lockups and freezes.
+        * disable it by default.
+        */
+       if (rdev->family == CHIP_RV515)
+               return false;
        if (rdev->flags & RADEON_IS_IGP) {
                /* APUs work fine with MSIs */
                if (rdev->family >= CHIP_PALM)