drm/xe/display: Do not allocate into stolen for new framebuffers.

Prefer to use system memory for global framebuffers, and reserve
the space for FBC use only.

Now that multiple CRTC's can use FBC's, the simple heuristic
of using less than half of stolen is no longer sufficient.

Additionally, there are reports of system hangs when using stolen
memory, and there are also various workarounds that are avoided
by using system memory instead.

Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/work_items/7513
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patch.msgid.link/20260630135523.1775379-4-dev@lankhorst.se
Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
Acked-by: Matthew Brost <matthew.brost@intel.com> #teams

1 files changed, 6 insertions, 27 deletions

diff --git a/drivers/gpu/drm/xe/display/xe_display_bo.c b/drivers/gpu/drm/xe/display/xe_display_bo.c
index 7fbac223b097..a6b5b88de9cc 100644
--- a/drivers/gpu/drm/xe/display/xe_display_bo.c
+++ b/drivers/gpu/drm/xe/display/xe_display_bo.c
@@ -146,33 +146,12 @@ static struct drm_gem_object *xe_display_bo_fbdev_create(struct drm_device *drm,
 	struct xe_device *xe = to_xe_device(drm);
 	struct xe_bo *obj;
 
-	obj = ERR_PTR(-ENODEV);
-
-	if (xe_display_bo_fbdev_prefer_stolen(xe, size)) {
-		obj = xe_bo_create_pin_map_novm(xe, xe_device_get_root_tile(xe),
-						size,
-						ttm_bo_type_kernel,
-						XE_BO_FLAG_FORCE_WC |
-						XE_BO_FLAG_STOLEN |
-						XE_BO_FLAG_GGTT,
-						false);
-		if (!IS_ERR(obj))
-			drm_info(&xe->drm, "Allocated fbdev into stolen\n");
-		else
-			drm_info(&xe->drm, "Allocated fbdev into stolen failed: %li\n", PTR_ERR(obj));
-	} else {
-		drm_info(&xe->drm, "Allocating fbdev: Stolen memory not preferred.\n");
-	}
-
-	if (IS_ERR(obj)) {
-		obj = xe_bo_create_pin_map_novm(xe, xe_device_get_root_tile(xe), size,
-						ttm_bo_type_kernel,
-						XE_BO_FLAG_FORCE_WC |
-						XE_BO_FLAG_VRAM_IF_DGFX(xe_device_get_root_tile(xe)) |
-						XE_BO_FLAG_GGTT,
-						false);
-	}
-
+	obj = xe_bo_create_pin_map_novm(xe, xe_device_get_root_tile(xe), size,
+					ttm_bo_type_kernel,
+					XE_BO_FLAG_FORCE_WC |
+					XE_BO_FLAG_VRAM_IF_DGFX(xe_device_get_root_tile(xe)) |
+					XE_BO_FLAG_GGTT,
+					false);
 	if (IS_ERR(obj)) {
 		drm_err(&xe->drm, "failed to allocate framebuffer (%pe)\n", obj);
 		return ERR_PTR(-ENOMEM);