[PATCH v6 29/33] iommu/mediatek: Add iova reserved function

Yong Wu
2021-01-11T11:24:47Z

For multiple iommu_domains, we need to reserve some iova regions. Take a
example, If the default iova region is 0 ~ 4G, but the 0x4000_0000 ~
0x43ff_ffff is only for the special CCU0 domain. Thus we should exclude
this region for the default iova region.

Signed-off-by: Anan sun <anan.sun@mediatek.com>
Signed-off-by: Chao Hao <chao.hao@mediatek.com>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
---
drivers/iommu/mtk_iommu.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index b42fd2535b77..764dc0b93477 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -626,6 +626,35 @@ static int mtk_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
return iommu_fwspec_add_ids(dev, args->args, 1);
}

+static void mtk_iommu_get_resv_regions(struct device *dev,
+ struct list_head *head)
+{
+ struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
+ unsigned int domid = mtk_iommu_get_domain_id(dev, data->plat_data), i;
+ const struct mtk_iommu_iova_region *resv, *curdom;
+ struct iommu_resv_region *region;
+ int prot = IOMMU_WRITE | IOMMU_READ;
+
+ if (domid < 0)
+ return;
+ curdom = data->plat_data->iova_region + domid;
+ for (i = 0; i < data->plat_data->iova_region_nr; i++) {
+ resv = data->plat_data->iova_region + i;
+
+ /* Only reserve when the region is inside the current domain */
+ if (resv->iova_base <= curdom->iova_base ||
+ resv->iova_base + resv->size >= curdom->iova_base + curdom->size)
+ continue;
+
+ region = iommu_alloc_resv_region(resv->iova_base, resv->size,
+ prot, IOMMU_RESV_RESERVED);
+ if (!region)
+ return;
+
+ list_add_tail(&region->list, head);
+ }
+}
+
static const struct iommu_ops mtk_iommu_ops = {
.domain_alloc = mtk_iommu_domain_alloc,
.domain_free = mtk_iommu_domain_free,
@@ -641,6 +670,8 @@ static const struct iommu_ops mtk_iommu_ops = {
.release_device = mtk_iommu_release_device,
.device_group = mtk_iommu_device_group,
.of_xlate = mtk_iommu_of_xlate,
+ .get_resv_regions = mtk_iommu_get_resv_regions,
+ .put_resv_regions = generic_iommu_put_resv_regions,
.pgsize_bitmap = SZ_4K | SZ_64K | SZ_1M | SZ_16M,
};

--
2.18.0