From: Fangyu Yu Add support for Sv39x4/Sv48x4/Sv57x4 Second-stage page tables used by the RISC-V IOMMU iohgatp register. The x4 root page table is 16 KiB instead of the usual 4 KiB, covering 2 extra GPA bits (hw_max_vasz_lg2 = 41/50/59). Signed-off-by: Fangyu Yu --- drivers/iommu/generic_pt/fmt/riscv.h | 61 +++++++++++++++++++++++++--- include/linux/generic_pt/common.h | 5 ++- include/linux/generic_pt/iommu.h | 17 +++++++- 3 files changed, 76 insertions(+), 7 deletions(-) diff --git a/drivers/iommu/generic_pt/fmt/riscv.h b/drivers/iommu/generic_pt/fmt/riscv.h index a7fef6266a36..777887335696 100644 --- a/drivers/iommu/generic_pt/fmt/riscv.h +++ b/drivers/iommu/generic_pt/fmt/riscv.h @@ -37,7 +37,16 @@ enum { PT_MAX_OUTPUT_ADDRESS_LG2 = 34, PT_MAX_TOP_LEVEL = 1, #else - PT_MAX_VA_ADDRESS_LG2 = 57, + /* + * PT_MAX_VA_ADDRESS_LG2 is the upper bound accepted by the generic + * pt_iommu_init() range check. It must cover both first-stage and + * second-stage (G-stage) modes: + * + * First-stage (fsc/iosatp): Sv39=39, Sv48=48, Sv57=57 + * Second-stage (iohgatp): Sv39x4=41, Sv48x4=50, Sv57x4=59 + * + */ + PT_MAX_VA_ADDRESS_LG2 = 59, PT_MAX_OUTPUT_ADDRESS_LG2 = 56, PT_MAX_TOP_LEVEL = 4, #endif @@ -124,6 +133,14 @@ riscvpt_entry_num_contig_lg2(const struct pt_state *pts) static inline unsigned int riscvpt_num_items_lg2(const struct pt_state *pts) { + /* + * Second-stage (iohgatp) root page tables have 4x the usual number of + * entries (2048 = 2^11 instead of 512 = 2^9) to cover the 2 extra GPA + * bits in Sv39x4/Sv48x4/Sv57x4. Only the root (top) level is + * enlarged; all other levels remain at the standard 9-bit index width. + */ + if (pts_feature(pts, PT_FEAT_RISCV_S2) && pts->level == pts->range->top_level) + return PT_TABLEMEM_LG2SZ - ilog2(sizeof(u64)) + 2; return PT_TABLEMEM_LG2SZ - ilog2(sizeof(u64)); } #define pt_num_items_lg2 riscvpt_num_items_lg2 @@ -254,6 +271,7 @@ riscvpt_iommu_fmt_init(struct pt_iommu_riscv_64 *iommu_table, struct pt_riscv *table = &iommu_table->riscv_64pt; switch (cfg->common.hw_max_vasz_lg2) { + /* First-stage (fsc/iosatp): Sv39 / Sv48 / Sv57 */ case 39: pt_top_set_level(&table->common, 2); break; @@ -263,6 +281,19 @@ riscvpt_iommu_fmt_init(struct pt_iommu_riscv_64 *iommu_table, case 57: pt_top_set_level(&table->common, 4); break; + /* + * Second-stage (iohgatp): Sv39x4 / Sv48x4 / Sv57x4. + * The top level is the same as for the first-stage counterpart. + */ + case 41: + pt_top_set_level(&table->common, 2); + break; + case 50: + pt_top_set_level(&table->common, 3); + break; + case 59: + pt_top_set_level(&table->common, 4); + break; default: return -EINVAL; } @@ -283,10 +314,17 @@ riscvpt_iommu_fmt_hw_info(struct pt_iommu_riscv_64 *table, PT_WARN_ON(top_phys & ~PT_TOP_PHYS_MASK); /* - * See Table 3. Encodings of iosatp.MODE field" for DC.tx.SXL = 0: - * 8 = Sv39 = top level 2 - * 9 = Sv38 = top level 3 - * 10 = Sv57 = top level 4 + * Both first-stage (fsc/iosatp) and second-stage (iohgatp) share the + * same MODE numeric values for a given top level: + * top_level 2 -> MODE 8 (Sv39 / Sv39x4) + * top_level 3 -> MODE 9 (Sv48 / Sv48x4) + * top_level 4 -> MODE 10 (Sv57 / Sv57x4) + * + * The union members fsc_iosatp_mode and iohgatp_mode occupy the same + * byte; the caller selects the appropriate name based on domain type. + * + * See "Table 3. Encodings of iosatp.MODE field" (DC.tc.SXL = 0) and + * "Table 2. Encoding of iohgatp.MODE field" in the RISC-V IOMMU spec. */ info->fsc_iosatp_mode = top_range->top_level + 6; } @@ -294,6 +332,7 @@ riscvpt_iommu_fmt_hw_info(struct pt_iommu_riscv_64 *table, #if defined(GENERIC_PT_KUNIT) static const struct pt_iommu_riscv_64_cfg riscv_64_kunit_fmt_cfgs[] = { + /* First-stage (fsc/iosatp): Sv39 / Sv48 / Sv57 */ [0] = { .common.features = BIT(PT_FEAT_RISCV_SVNAPOT_64K), .common.hw_max_oasz_lg2 = 56, .common.hw_max_vasz_lg2 = 39 }, @@ -303,6 +342,18 @@ static const struct pt_iommu_riscv_64_cfg riscv_64_kunit_fmt_cfgs[] = { [2] = { .common.features = BIT(PT_FEAT_RISCV_SVNAPOT_64K), .common.hw_max_oasz_lg2 = 56, .common.hw_max_vasz_lg2 = 57 }, + /* + * Second-stage (iohgatp): Sv39x4 / Sv48x4 / Sv57x4. + */ + [3] = { .common.features = BIT(PT_FEAT_RISCV_SVNAPOT_64K), + .common.hw_max_oasz_lg2 = 56, + .common.hw_max_vasz_lg2 = 41 }, + [4] = { .common.features = 0, + .common.hw_max_oasz_lg2 = 56, + .common.hw_max_vasz_lg2 = 50 }, + [5] = { .common.features = BIT(PT_FEAT_RISCV_SVNAPOT_64K), + .common.hw_max_oasz_lg2 = 56, + .common.hw_max_vasz_lg2 = 59 }, }; #define kunit_fmt_cfgs riscv_64_kunit_fmt_cfgs enum { diff --git a/include/linux/generic_pt/common.h b/include/linux/generic_pt/common.h index fc5d0b5edadc..59448125159e 100644 --- a/include/linux/generic_pt/common.h +++ b/include/linux/generic_pt/common.h @@ -188,7 +188,10 @@ enum { * Support the 64k contiguous page size following the Svnapot extension. */ PT_FEAT_RISCV_SVNAPOT_64K = PT_FEAT_FMT_START, - + /* + * Using second-stage / iohgatp address translation. + */ + PT_FEAT_RISCV_S2, }; struct pt_x86_64 { diff --git a/include/linux/generic_pt/iommu.h b/include/linux/generic_pt/iommu.h index dd0edd02a48a..f27d229ff318 100644 --- a/include/linux/generic_pt/iommu.h +++ b/include/linux/generic_pt/iommu.h @@ -328,7 +328,22 @@ struct pt_iommu_riscv_64_cfg { struct pt_iommu_riscv_64_hw_info { u64 ppn; - u8 fsc_iosatp_mode; + union { + /* + * First-stage (fsc/iosatp) MODE encoding: + * 8 = Sv39, 9 = Sv48, 10 = Sv57 + * Used to program DC.fsc.iosatp.MODE. + */ + u8 fsc_iosatp_mode; + /* + * Second-stage (iohgatp) MODE encoding: + * 8 = Sv39x4, 9 = Sv48x4, 10 = Sv57x4 + * Used to program DC.iohgatp.MODE. + * The numeric values are identical to fsc_iosatp_mode; + * the caller selects the interpretation based on domain type. + */ + u8 iohgatp_mode; + }; }; IOMMU_FORMAT(riscv_64, riscv_64pt); -- 2.50.1