If DRM begin to probe before SMI probe done. It will hang:
[ 7.832359] Call trace:
[ 7.834778] [<ffffffc000764424>] mtk_smi_larb_get+0x24/0xa8
[ 7.840300] [<ffffffc0005a1390>] mtk_drm_crtc_enable+0x6c/0x450
Use the new interface(mtk_smi_larb_is_ready) to wait for IOMMU and
SMI probe done.
Signed-off-by: Yong Wu <yong...@mediatek.com>
---
drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
index 3970fcf..3ef3124 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
@@ -21,6 +21,7 @@
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <drm/drmP.h>
+#include <soc/mediatek/smi.h>
#include "mtk_drm_drv.h"
#include "mtk_drm_plane.h"
#include "mtk_drm_ddp_comp.h"
@@ -201,6 +202,10 @@ int mtk_ddp_comp_init(struct device *dev, struct
device_node *node,
}
of_node_put(larb_node);
+ /* Wait until MTK IOMMU and SMI probe done.*/
+ if (!mtk_smi_larb_is_ready(&larb_pdev->dev))
+ return -EPROBE_DEFER;
+
comp->larb_dev = &larb_pdev->dev;
return 0;
--
1.8.1.1.dirty
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
