In the 4GB mode, the physical address is remapped, Here is the detailed remap relationship. CPU PA -> HW PA 0x4000_0000 0x1_4000_0000 (Add bit32) 0x8000_0000 0x1_8000_0000 ... 0xc000_0000 0x1_c000_0000 ... 0x1_0000_0000 0x1_0000_0000 (No change) The PA in the iova_to_phys that is got from v7s always is u32, But from the CPU point of view, PA should add BIT(32) when PA < 0x4000_0000. Fixes: 30e2fccf9512 ("iommu/mediatek: Enlarge the validate PA range for 4GB mode") Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx> --- drivers/iommu/mtk_iommu.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 1ddb2b7..fefc2e0 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -115,6 +115,19 @@ struct mtk_iommu_domain { static const struct iommu_ops mtk_iommu_ops; +/* + * In M4U 4GB mode, the physical address is remapped as below: + * CPU PA -> M4U HW PA + * 0x4000_0000 0x1_4000_0000 (Add bit32) + * 0x8000_0000 0x1_8000_0000 ... + * 0xc000_0000 0x1_c000_0000 ... + * 0x1_0000_0000 0x1_0000_0000 (No change) + * + * The PA in the iova_to_phys that is got from v7s always is u32, But from + * the CPU point of view, PA should add BIT(32) when PA < 0x4000_0000. + */ +#define MTK_IOMMU_4GB_MODE_REMAP_BASE 0x40000000 + static LIST_HEAD(m4ulist); /* List all the M4U HWs */ #define for_each_m4u(data) list_for_each_entry(data, &m4ulist, list) @@ -409,7 +422,7 @@ static phys_addr_t mtk_iommu_iova_to_phys(struct iommu_domain *domain, pa = dom->iop->iova_to_phys(dom->iop, iova); spin_unlock_irqrestore(&dom->pgtlock, flags); - if (data->enable_4GB) + if (data->enable_4GB && pa < MTK_IOMMU_4GB_MODE_REMAP_BASE) pa |= BIT_ULL(32); return pa; -- 1.9.1