[PATCH v3 18/33] iommu/mediatek: Adjust device link when it is sub-common

From: Yong Wu
Date: Thu Sep 23 2021 - 08:02:10 EST


For MM IOMMU, We always add device link between smi-common and IOMMU HW.
In mt8195, we add smi-sub-common. Thus, if the node is sub-common, we still
need find again to get smi-common, then do device link.

Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
---
drivers/iommu/mtk_iommu.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 2ebbb3412cb9..faea4a0d922f 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -786,9 +786,9 @@ 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 platform_device *plarbdev;
struct device_link *link;
- struct device_node *larbnode, *smicomm_node;
int i, larb_nr, ret;

larb_nr = of_count_phandle_with_args(dev->of_node, "mediatek,larbs", NULL);
@@ -822,11 +822,21 @@ static int mtk_iommu_mm_dts_parse(struct device *dev,
compare_of, larbnode);
}

- /* Get smi-common dev from the last larb. */
- smicomm_node = of_parse_phandle(larbnode, "mediatek,smi", 0);
- if (!smicomm_node)
+ /* 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;

+ /*
+ * It may have two level smi-common. the node is smi-sub-common if it
+ * has a new mediatek,smi property. otherwise it is smi-commmon.
+ */
+ smicomm_node = of_parse_phandle(smi_subcomm_node, "mediatek,smi", 0);
+ if (smicomm_node)
+ of_node_put(smi_subcomm_node);
+ else
+ smicomm_node = smi_subcomm_node;
+
plarbdev = of_find_device_by_node(smicomm_node);
of_node_put(smicomm_node);
data->smicomm_dev = &plarbdev->dev;
--
2.18.0