As the removed property in the vcodec dt-binding, the property is: dma-ranges = <0x1 0x0 0x0 0x40000000 0x0 0xfff00000>; The length is 0xfff0_0000 rather than 0x1_0000_0000, this means it requires 1M as a gap. This is because the end address for some vcodec HW is (address + size). If the size is 4G, the end address may be 0x2_0000_0000, and the width for vcodec register only is 32, then the HW may get the ZERO address. Currently the consumer's dma-ranges property doesn't work, IOMMU has to consider this case. Add a bigger gap(8M) for all the regions to avoid it. Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> --- Hi AngeloGioacchino, I define a new macro for this, I think it is a small change, thus keep you R-b. Thanks. --- drivers/iommu/mtk_iommu.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index fbfc5e4e56a8..e0264d5f1c9a 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -332,8 +332,10 @@ static LIST_HEAD(m4ulist); /* List all the M4U HWs */ #define for_each_m4u(data, head) list_for_each_entry(data, head, list) +#define MTK_IOMMU_IOVA_SZ_4G (SZ_4G - SZ_8M) /* 8M as gap */ + static const struct mtk_iommu_iova_region single_domain[] = { - {.iova_base = 0, .size = SZ_4G}, + {.iova_base = 0, .size = MTK_IOMMU_IOVA_SZ_4G}, }; #define MT8192_MULTI_REGION_NR_MAX 6 @@ -342,11 +344,11 @@ static const struct mtk_iommu_iova_region single_domain[] = { MT8192_MULTI_REGION_NR_MAX : 1) static const struct mtk_iommu_iova_region mt8192_multi_dom[MT8192_MULTI_REGION_NR] = { - { .iova_base = 0x0, .size = SZ_4G}, /* 0 ~ 4G */ + { .iova_base = 0x0, .size = MTK_IOMMU_IOVA_SZ_4G}, /* 0 ~ 4G, */ #if IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT) - { .iova_base = SZ_4G, .size = SZ_4G}, /* 4G ~ 8G */ - { .iova_base = SZ_4G * 2, .size = SZ_4G}, /* 8G ~ 12G */ - { .iova_base = SZ_4G * 3, .size = SZ_4G}, /* 12G ~ 16G */ + { .iova_base = SZ_4G, .size = MTK_IOMMU_IOVA_SZ_4G}, /* 4G ~ 8G */ + { .iova_base = SZ_4G * 2, .size = MTK_IOMMU_IOVA_SZ_4G}, /* 8G ~ 12G */ + { .iova_base = SZ_4G * 3, .size = MTK_IOMMU_IOVA_SZ_4G}, /* 12G ~ 16G */ { .iova_base = 0x240000000ULL, .size = 0x4000000}, /* CCU0 */ { .iova_base = 0x244000000ULL, .size = 0x4000000}, /* CCU1 */ -- 2.18.0