Commit 6cde583d authored by Yong Wu's avatar Yong Wu Committed by Joerg Roedel
Browse files

iommu/mediatek: Improve safety for mediatek,smi property in larb nodes 



No functional change. Just improve safety from dts.

All the larbs that connect to one IOMMU must connect with the same
smi-common. This patch checks all the mediatek,smi property for each
larb, If their mediatek,smi are different, it will return fails.
Also avoid there is no available smi-larb nodes.

Suggested-by: default avatarGuenter Roeck <groeck@chromium.org>
Signed-off-by: default avatarYong Wu <yong.wu@mediatek.com>
Reviewed-by: default avatarAngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: default avatarMatthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20221018024258.19073-6-yong.wu@mediatek.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent ef693a84

drivers/iommu/mtk_iommu.c

+37 −16
Original line number Diff line number Diff line
@@ -1054,7 +1054,7 @@ static const struct component_master_ops mtk_iommu_com_ops = { 
static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **match,

				  struct mtk_iommu_data *data)

{

	struct device_node *larbnode, *smicomm_node, *smi_subcomm_node;

	struct device_node *larbnode, *frst_avail_smicomm_node = NULL;

	struct platform_device *plarbdev, *pcommdev;

	struct device_link *link;

	int i, larb_nr, ret;
@@ -1066,6 +1066,7 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m 
		return -EINVAL;



	for (i = 0; i < larb_nr; i++) {

		struct device_node *smicomm_node, *smi_subcomm_node;

		u32 id;



		larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i);
@@ -1106,14 +1107,12 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m 
			goto err_larbdev_put;

		}



		component_match_add(dev, match, component_compare_dev, &plarbdev->dev);

		platform_device_put(plarbdev);

	}



		/* Get smi-(sub)-common dev from the last larb. */

		smi_subcomm_node = of_parse_phandle(larbnode, "mediatek,smi", 0);

	if (!smi_subcomm_node)

		return -EINVAL;

		if (!smi_subcomm_node) {

			ret = -EINVAL;

			goto err_larbdev_put;

		}



		/*

		 * It may have two level smi-common. the node is smi-sub-common if it
@@ -1125,8 +1124,30 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m 
		else

			smicomm_node = smi_subcomm_node;



	pcommdev = of_find_device_by_node(smicomm_node);

		/*

		 * All the larbs that connect to one IOMMU must connect with the same

		 * smi-common.

		 */

		if (!frst_avail_smicomm_node) {

			frst_avail_smicomm_node = smicomm_node;

		} else if (frst_avail_smicomm_node != smicomm_node) {

			dev_err(dev, "mediatek,smi property is not right @larb%d.", id);

			of_node_put(smicomm_node);

			ret = -EINVAL;

			goto err_larbdev_put;

		} else {

			of_node_put(smicomm_node);

		}



		component_match_add(dev, match, component_compare_dev, &plarbdev->dev);

		platform_device_put(plarbdev);

	}



	if (!frst_avail_smicomm_node)

		return -EINVAL;



	pcommdev = of_find_device_by_node(frst_avail_smicomm_node);

	of_node_put(frst_avail_smicomm_node);

	if (!pcommdev)

		return -ENODEV;

	data->smicomm_dev = &pcommdev->dev;