drm/radeon/kms: Fix R600 write back buffer

This split write back buffer handling into 3 functions,
wb_fini for cleanup, wb_enable/wb_disable for enabling/disabling
write back used for suspend/resume. This should fix
potential issue of letting the write back active before
suspending. We need to allocate memory in wb_enable because
we can only allocate once GART is running.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 33 insertions, 34 deletions

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 17fff7b6e591..11fa801a2c52 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -1350,32 +1350,47 @@ int r600_ring_test(struct radeon_device *rdev)
         return r;
 }
 
-/*
- * Writeback
- */
-int r600_wb_init(struct radeon_device *rdev)
+void r600_wb_disable(struct radeon_device *rdev)
+{
+        WREG32(SCRATCH_UMSK, 0);
+        if (rdev->wb.wb_obj) {
+                radeon_object_kunmap(rdev->wb.wb_obj);
+                radeon_object_unpin(rdev->wb.wb_obj);
+        }
+}
+
+void r600_wb_fini(struct radeon_device *rdev)
+{
+        r600_wb_disable(rdev);
+        if (rdev->wb.wb_obj) {
+                radeon_object_unref(&rdev->wb.wb_obj);
+                rdev->wb.wb = NULL;
+                rdev->wb.wb_obj = NULL;
+        }
+}
+
+int r600_wb_enable(struct radeon_device *rdev)
 {
         int r;
 
         if (rdev->wb.wb_obj == NULL) {
-                r = radeon_object_create(rdev, NULL, 4096,
-                                         true,
-                                         RADEON_GEM_DOMAIN_GTT,
-                                         false, &rdev->wb.wb_obj);
+                r = radeon_object_create(rdev, NULL, 4096, true,
+                                RADEON_GEM_DOMAIN_GTT, false, &rdev->wb.wb_obj);
                 if (r) {
-                        DRM_ERROR("radeon: failed to create WB buffer (%d).\n", r);
+                        dev_warn(rdev->dev, "failed to create WB buffer (%d).\n", r);
                         return r;
                 }
-                r = radeon_object_pin(rdev->wb.wb_obj,
-                                      RADEON_GEM_DOMAIN_GTT,
-                                      &rdev->wb.gpu_addr);
+                r = radeon_object_pin(rdev->wb.wb_obj, RADEON_GEM_DOMAIN_GTT,
+                                &rdev->wb.gpu_addr);
                 if (r) {
-                        DRM_ERROR("radeon: failed to pin WB buffer (%d).\n", r);
+                        dev_warn(rdev->dev, "failed to pin WB buffer (%d).\n", r);
+                        r600_wb_fini(rdev);
                         return r;
                 }
                 r = radeon_object_kmap(rdev->wb.wb_obj, (void **)&rdev->wb.wb);
                 if (r) {
-                        DRM_ERROR("radeon: failed to map WB buffer (%d).\n", r);
+                        dev_warn(rdev->dev, "failed to map WB buffer (%d).\n", r);
+                        r600_wb_fini(rdev);
                         return r;
                 }
         }
@@ -1386,21 +1401,6 @@ int r600_wb_init(struct radeon_device *rdev)
         return 0;
 }
 
-void r600_wb_fini(struct radeon_device *rdev)
-{
-        if (rdev->wb.wb_obj) {
-                radeon_object_kunmap(rdev->wb.wb_obj);
-                radeon_object_unpin(rdev->wb.wb_obj);
-                radeon_object_unref(&rdev->wb.wb_obj);
-                rdev->wb.wb = NULL;
-                rdev->wb.wb_obj = NULL;
-        }
-}
-
-
-/*
- * CS
- */
 void r600_fence_ring_emit(struct radeon_device *rdev,
                           struct radeon_fence *fence)
 {
@@ -1500,9 +1500,8 @@ int r600_startup(struct radeon_device *rdev)
         r = r600_cp_resume(rdev);
         if (r)
                 return r;
-        r = r600_wb_init(rdev);
-        if (r)
-                return r;
+        /* write back buffer are not vital so don't worry about failure */
+        r600_wb_enable(rdev);
         return 0;
 }
 
@@ -1539,13 +1538,12 @@ int r600_resume(struct radeon_device *rdev)
         return r;
 }
 
-
 int r600_suspend(struct radeon_device *rdev)
 {
         /* FIXME: we should wait for ring to be empty */
         r600_cp_stop(rdev);
         rdev->cp.ready = false;
-
+        r600_wb_disable(rdev);
         r600_pcie_gart_disable(rdev);
         /* unpin shaders bo */
         radeon_object_unpin(rdev->r600_blit.shader_obj);
@@ -1668,6 +1666,7 @@ void r600_fini(struct radeon_device *rdev)
 
         r600_blit_fini(rdev);
         radeon_ring_fini(rdev);
+        r600_wb_fini(rdev);
         r600_pcie_gart_fini(rdev);
         radeon_gem_fini(rdev);
         radeon_fence_driver_fini(rdev);