[PATCH 2/3] iommu: mediatek: Add support of unmanaged iommu domain

Alexandre Bailon abailon at baylibre.com
Mon Jan 30 02:27:21 PST 2023


Currently, the driver can allocate an unmanaged iommu domain.
But, this only works for SoC having multiple bank or multiple iova region.
This updates the driver to also support unmanaged iommu domain if
MTK_UNMANAGED_DEVICE is set in the iommu id.

Signed-off-by: Alexandre Bailon <abailon at baylibre.com>
---
 drivers/iommu/mtk_iommu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 2badd6acfb23d..5884a1ad409a0 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -858,9 +858,15 @@ static int mtk_iommu_get_group_id(struct device *dev, const struct mtk_iommu_pla
 static struct iommu_group *mtk_iommu_device_group(struct device *dev)
 {
 	struct mtk_iommu_data *c_data = dev_iommu_priv_get(dev), *data;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 	struct list_head *hw_list = c_data->hw_list;
 	struct iommu_group *group;
 	int groupid;
+	int i;
+
+	for (i = 0; i < fwspec->num_ids; i++)
+		if (MTK_M4U_UNMANAGED(fwspec->ids[i]))
+			return iommu_group_alloc();
 
 	data = mtk_iommu_get_frst_data(hw_list);
 	if (!data)
-- 
2.38.2




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