drm/radeon/kms: clean up gart dummy page handling

As per Konrad's original patch, the dummy page used
by the gart code and allocated in radeon_gart_init()
was not freed properly in radeon_gart_fini().

At the same time r6xx and newer allocated and freed the
dummy page on their own.  So to do Konrad's patch one
better, just remove the allocation and freeing of the
dummy page in the r6xx, 7xx, evergreen, and ni code and
allocate and free in the gart_init/fini() functions for
all asics.

Cc: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/evergreen.c

@@ -3036,9 +3036,6 @@ int evergreen_init(struct radeon_device *rdev)
 {
 	int r;
 
-	r = radeon_dummy_page_init(rdev);
-	if (r)
-		return r;
 	/* This don't do much */
 	r = radeon_gem_init(rdev);
 	if (r)
@@ -3150,7 +3147,6 @@ void evergreen_fini(struct radeon_device *rdev)
 	radeon_atombios_fini(rdev);
 	kfree(rdev->bios);
 	rdev->bios = NULL;
-	radeon_dummy_page_fini(rdev);
 }
 
 static void evergreen_pcie_gen2_enable(struct radeon_device *rdev)

drivers/gpu/drm/radeon/r600.c

@@ -2509,9 +2509,6 @@ int r600_init(struct radeon_device *rdev)
 {
 	int r;
 
-	r = radeon_dummy_page_init(rdev);
-	if (r)
-		return r;
 	if (r600_debugfs_mc_info_init(rdev)) {
 		DRM_ERROR("Failed to register debugfs file for mc !\n");
 	}
@@ -2625,7 +2622,6 @@ void r600_fini(struct radeon_device *rdev)
 	radeon_atombios_fini(rdev);
 	kfree(rdev->bios);
 	rdev->bios = NULL;
-	radeon_dummy_page_fini(rdev);
 }
 
 

drivers/gpu/drm/radeon/radeon_gart.c

@@ -285,4 +285,6 @@ void radeon_gart_fini(struct radeon_device *rdev)
 	rdev->gart.pages = NULL;
 	rdev->gart.pages_addr = NULL;
 	rdev->gart.ttm_alloced = NULL;
+
+	radeon_dummy_page_fini(rdev);
 }

drivers/gpu/drm/radeon/rv770.c

@@ -1255,9 +1255,6 @@ int rv770_init(struct radeon_device *rdev)
 {
 	int r;
 
-	r = radeon_dummy_page_init(rdev);
-	if (r)
-		return r;
 	/* This don't do much */
 	r = radeon_gem_init(rdev);
 	if (r)
@@ -1372,7 +1369,6 @@ void rv770_fini(struct radeon_device *rdev)
 	radeon_atombios_fini(rdev);
 	kfree(rdev->bios);
 	rdev->bios = NULL;
-	radeon_dummy_page_fini(rdev);
 }
 
 static void rv770_pcie_gen2_enable(struct radeon_device *rdev)