[PATCH 1/2] iommu: Report domain nesting info for arm-smmu-v3

From: Vivek Gautam
Date: Fri Feb 12 2021 - 06:01:36 EST


Add a vendor specific structure for domain nesting info for
arm smmu-v3, and necessary info fields required to populate
stage1 page tables.

Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxx>
---
include/uapi/linux/iommu.h | 31 +++++++++++++++++++++++++------
1 file changed, 25 insertions(+), 6 deletions(-)

diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
index 4d3d988fa353..5f059bcf7720 100644
--- a/include/uapi/linux/iommu.h
+++ b/include/uapi/linux/iommu.h
@@ -323,7 +323,8 @@ struct iommu_gpasid_bind_data {
#define IOMMU_GPASID_BIND_VERSION_1 1
__u32 version;
#define IOMMU_PASID_FORMAT_INTEL_VTD 1
-#define IOMMU_PASID_FORMAT_LAST 2
+#define IOMMU_PASID_FORMAT_ARM_SMMU_V3 2
+#define IOMMU_PASID_FORMAT_LAST 3
__u32 format;
__u32 addr_width;
#define IOMMU_SVA_GPASID_VAL (1 << 0) /* guest PASID valid */
@@ -409,6 +410,21 @@ struct iommu_nesting_info_vtd {
__u64 ecap_reg;
};

+/*
+ * struct iommu_nesting_info_arm_smmuv3 - Arm SMMU-v3 nesting info.
+ */
+struct iommu_nesting_info_arm_smmuv3 {
+ __u32 flags;
+ __u16 asid_bits;
+
+ /* Arm LPAE page table format as per kernel */
+#define ARM_PGTBL_32_LPAE_S1 (0x0)
+#define ARM_PGTBL_64_LPAE_S1 (0x2)
+ __u8 pgtbl_fmt;
+
+ __u8 padding[9];
+};
+
/*
* struct iommu_nesting_info - Information for nesting-capable IOMMU.
* userspace should check it before using
@@ -445,11 +461,13 @@ struct iommu_nesting_info_vtd {
* +---------------+------------------------------------------------------+
*
* data struct types defined for @format:
- * +================================+=====================================+
- * | @format | data struct |
- * +================================+=====================================+
- * | IOMMU_PASID_FORMAT_INTEL_VTD | struct iommu_nesting_info_vtd |
- * +--------------------------------+-------------------------------------+
+ * +================================+======================================+
+ * | @format | data struct |
+ * +================================+======================================+
+ * | IOMMU_PASID_FORMAT_INTEL_VTD | struct iommu_nesting_info_vtd |
+ * +---------------+-------------------------------------------------------+
+ * | IOMMU_PASID_FORMAT_ARM_SMMU_V3 | struct iommu_nesting_info_arm_smmuv3 |
+ * +--------------------------------+--------------------------------------+
*
*/
struct iommu_nesting_info {
@@ -466,6 +484,7 @@ struct iommu_nesting_info {
/* Vendor specific data */
union {
struct iommu_nesting_info_vtd vtd;
+ struct iommu_nesting_info_arm_smmuv3 smmuv3;
} vendor;
};

--
2.17.1