diff options
Diffstat (limited to 'target/loongarch/tlb_helper.c')
| -rw-r--r-- | target/loongarch/tlb_helper.c | 315 |
1 files changed, 315 insertions, 0 deletions
diff --git a/target/loongarch/tlb_helper.c b/target/loongarch/tlb_helper.c new file mode 100644 index 0000000000..fad8bc7746 --- /dev/null +++ b/target/loongarch/tlb_helper.c @@ -0,0 +1,315 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * QEMU LoongArch TLB helpers + * + * Copyright (c) 2021 Loongson Technology Corporation Limited + * + */ + +#include "qemu/osdep.h" + +#include "cpu.h" +#include "internals.h" +#include "exec/exec-all.h" +#include "exec/cpu_ldst.h" +#include "exec/log.h" +#include "cpu-csr.h" + +enum { + TLBRET_MATCH = 0, + TLBRET_BADADDR = 1, + TLBRET_NOMATCH = 2, + TLBRET_INVALID = 3, + TLBRET_DIRTY = 4, + TLBRET_RI = 5, + TLBRET_XI = 6, + TLBRET_PE = 7, +}; + +static int loongarch_map_tlb_entry(CPULoongArchState *env, hwaddr *physical, + int *prot, target_ulong address, + int access_type, int index, int mmu_idx) +{ + LoongArchTLB *tlb = &env->tlb[index]; + uint64_t plv = mmu_idx; + uint64_t tlb_entry, tlb_ppn; + uint8_t tlb_ps, n, tlb_v, tlb_d, tlb_plv, tlb_nx, tlb_nr, tlb_rplv; + + if (index >= LOONGARCH_STLB) { + tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS); + } else { + tlb_ps = FIELD_EX64(env->CSR_STLBPS, CSR_STLBPS, PS); + } + n = (address >> tlb_ps) & 0x1;/* Odd or even */ + + tlb_entry = n ? tlb->tlb_entry1 : tlb->tlb_entry0; + tlb_v = FIELD_EX64(tlb_entry, TLBENTRY, V); + tlb_d = FIELD_EX64(tlb_entry, TLBENTRY, D); + tlb_plv = FIELD_EX64(tlb_entry, TLBENTRY, PLV); + tlb_ppn = FIELD_EX64(tlb_entry, TLBENTRY, PPN); + tlb_nx = FIELD_EX64(tlb_entry, TLBENTRY, NX); + tlb_nr = FIELD_EX64(tlb_entry, TLBENTRY, NR); + tlb_rplv = FIELD_EX64(tlb_entry, TLBENTRY, RPLV); + + /* Check access rights */ + if (!tlb_v) { + return TLBRET_INVALID; + } + + if (access_type == MMU_INST_FETCH && tlb_nx) { + return TLBRET_XI; + } + + if (access_type == MMU_DATA_LOAD && tlb_nr) { + return TLBRET_RI; + } + + if (((tlb_rplv == 0) && (plv > tlb_plv)) || + ((tlb_rplv == 1) && (plv != tlb_plv))) { + return TLBRET_PE; + } + + if ((access_type == MMU_DATA_STORE) && !tlb_d) { + return TLBRET_DIRTY; + } + + /* + * tlb_entry contains ppn[47:12] while 16KiB ppn is [47:15] + * need adjust. + */ + *physical = (tlb_ppn << R_TLBENTRY_PPN_SHIFT) | + (address & MAKE_64BIT_MASK(0, tlb_ps)); + *prot = PAGE_READ; + if (tlb_d) { + *prot |= PAGE_WRITE; + } + if (!tlb_nx) { + *prot |= PAGE_EXEC; + } + return TLBRET_MATCH; +} + +/* + * One tlb entry holds an adjacent odd/even pair, the vpn is the + * content of the virtual page number divided by 2. So the + * compare vpn is bit[47:15] for 16KiB page. while the vppn + * field in tlb entry contains bit[47:13], so need adjust. + * virt_vpn = vaddr[47:13] + */ +static bool loongarch_tlb_search(CPULoongArchState *env, target_ulong vaddr, + int *index) +{ + LoongArchTLB *tlb; + uint16_t csr_asid, tlb_asid, stlb_idx; + uint8_t tlb_e, tlb_ps, tlb_g, stlb_ps; + int i, compare_shift; + uint64_t vpn, tlb_vppn; + + csr_asid = FIELD_EX64(env->CSR_ASID, CSR_ASID, ASID); + stlb_ps = FIELD_EX64(env->CSR_STLBPS, CSR_STLBPS, PS); + vpn = (vaddr & TARGET_VIRT_MASK) >> (stlb_ps + 1); + stlb_idx = vpn & 0xff; /* VA[25:15] <==> TLBIDX.index for 16KiB Page */ + compare_shift = stlb_ps + 1 - R_TLB_MISC_VPPN_SHIFT; + + /* Search STLB */ + for (i = 0; i < 8; ++i) { + tlb = &env->tlb[i * 256 + stlb_idx]; + tlb_e = FIELD_EX64(tlb->tlb_misc, TLB_MISC, E); + if (tlb_e) { + tlb_vppn = FIELD_EX64(tlb->tlb_misc, TLB_MISC, VPPN); + tlb_asid = FIELD_EX64(tlb->tlb_misc, TLB_MISC, ASID); + tlb_g = FIELD_EX64(tlb->tlb_entry0, TLBENTRY, G); + + if ((tlb_g == 1 || tlb_asid == csr_asid) && + (vpn == (tlb_vppn >> compare_shift))) { + *index = i * 256 + stlb_idx; + return true; + } + } + } + + /* Search MTLB */ + for (i = LOONGARCH_STLB; i < LOONGARCH_TLB_MAX; ++i) { + tlb = &env->tlb[i]; + tlb_e = FIELD_EX64(tlb->tlb_misc, TLB_MISC, E); + if (tlb_e) { + tlb_vppn = FIELD_EX64(tlb->tlb_misc, TLB_MISC, VPPN); + tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS); + tlb_asid = FIELD_EX64(tlb->tlb_misc, TLB_MISC, ASID); + tlb_g = FIELD_EX64(tlb->tlb_entry0, TLBENTRY, G); + compare_shift = tlb_ps + 1 - R_TLB_MISC_VPPN_SHIFT; + vpn = (vaddr & TARGET_VIRT_MASK) >> (tlb_ps + 1); + if ((tlb_g == 1 || tlb_asid == csr_asid) && + (vpn == (tlb_vppn >> compare_shift))) { + *index = i; + return true; + } + } + } + return false; +} + +static int loongarch_map_address(CPULoongArchState *env, hwaddr *physical, + int *prot, target_ulong address, + MMUAccessType access_type, int mmu_idx) +{ + int index, match; + + match = loongarch_tlb_search(env, address, &index); + if (match) { + return loongarch_map_tlb_entry(env, physical, prot, + address, access_type, index, mmu_idx); + } + + return TLBRET_NOMATCH; +} + +static int get_physical_address(CPULoongArchState *env, hwaddr *physical, + int *prot, target_ulong address, + MMUAccessType access_type, int mmu_idx) +{ + int user_mode = mmu_idx == MMU_USER_IDX; + int kernel_mode = mmu_idx == MMU_KERNEL_IDX; + uint32_t plv, base_c, base_v; + int64_t addr_high; + uint8_t da = FIELD_EX64(env->CSR_CRMD, CSR_CRMD, DA); + uint8_t pg = FIELD_EX64(env->CSR_CRMD, CSR_CRMD, PG); + + /* Check PG and DA */ + if (da & !pg) { + *physical = address & TARGET_PHYS_MASK; + *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; + return TLBRET_MATCH; + } + + plv = kernel_mode | (user_mode << R_CSR_DMW_PLV3_SHIFT); + base_v = address >> TARGET_VIRT_ADDR_SPACE_BITS; + /* Check direct map window */ + for (int i = 0; i < 4; i++) { + base_c = env->CSR_DMW[i] >> TARGET_VIRT_ADDR_SPACE_BITS; + if ((plv & env->CSR_DMW[i]) && (base_c == base_v)) { + *physical = dmw_va2pa(address); + *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; + return TLBRET_MATCH; + } + } + + /* Check valid extension */ + addr_high = sextract64(address, TARGET_VIRT_ADDR_SPACE_BITS, 16); + if (!(addr_high == 0 || addr_high == -1)) { + return TLBRET_BADADDR; + } + + /* Mapped address */ + return loongarch_map_address(env, physical, prot, address, + access_type, mmu_idx); +} + +hwaddr loongarch_cpu_get_phys_page_debug(CPUState *cs, vaddr addr) +{ + LoongArchCPU *cpu = LOONGARCH_CPU(cs); + CPULoongArchState *env = &cpu->env; + hwaddr phys_addr; + int prot; + + if (get_physical_address(env, &phys_addr, &prot, addr, MMU_DATA_LOAD, + cpu_mmu_index(env, false)) != 0) { + return -1; + } + return phys_addr; +} + +static void raise_mmu_exception(CPULoongArchState *env, target_ulong address, + MMUAccessType access_type, int tlb_error) +{ + CPUState *cs = env_cpu(env); + + switch (tlb_error) { + default: + case TLBRET_BADADDR: + cs->exception_index = EXCCODE_ADEM; + break; + case TLBRET_NOMATCH: + /* No TLB match for a mapped address */ + if (access_type == MMU_DATA_LOAD) { + cs->exception_index = EXCCODE_PIL; + } else if (access_type == MMU_DATA_STORE) { + cs->exception_index = EXCCODE_PIS; + } else if (access_type == MMU_INST_FETCH) { + cs->exception_index = EXCCODE_PIF; + } + env->CSR_TLBRERA = FIELD_DP64(env->CSR_TLBRERA, CSR_TLBRERA, ISTLBR, 1); + break; + case TLBRET_INVALID: + /* TLB match with no valid bit */ + if (access_type == MMU_DATA_LOAD) { + cs->exception_index = EXCCODE_PIL; + } else if (access_type == MMU_DATA_STORE) { + cs->exception_index = EXCCODE_PIS; + } else if (access_type == MMU_INST_FETCH) { + cs->exception_index = EXCCODE_PIF; + } + break; + case TLBRET_DIRTY: + /* TLB match but 'D' bit is cleared */ + cs->exception_index = EXCCODE_PME; + break; + case TLBRET_XI: + /* Execute-Inhibit Exception */ + cs->exception_index = EXCCODE_PNX; + break; + case TLBRET_RI: + /* Read-Inhibit Exception */ + cs->exception_index = EXCCODE_PNR; + break; + case TLBRET_PE: + /* Privileged Exception */ + cs->exception_index = EXCCODE_PPI; + break; + } + + if (tlb_error == TLBRET_NOMATCH) { + env->CSR_TLBRBADV = address; + env->CSR_TLBREHI = FIELD_DP64(env->CSR_TLBREHI, CSR_TLBREHI, VPPN, + extract64(address, 13, 35)); + } else { + if (!FIELD_EX64(env->CSR_DBG, CSR_DBG, DST)) { + env->CSR_BADV = address; + } + env->CSR_TLBEHI = address & (TARGET_PAGE_MASK << 1); + } +} + +bool loongarch_cpu_tlb_fill(CPUState *cs, vaddr address, int size, + MMUAccessType access_type, int mmu_idx, + bool probe, uintptr_t retaddr) +{ + LoongArchCPU *cpu = LOONGARCH_CPU(cs); + CPULoongArchState *env = &cpu->env; + hwaddr physical; + int prot; + int ret = TLBRET_BADADDR; + + /* Data access */ + ret = get_physical_address(env, &physical, &prot, address, + access_type, mmu_idx); + + if (ret == TLBRET_MATCH) { + tlb_set_page(cs, address & TARGET_PAGE_MASK, + physical & TARGET_PAGE_MASK, prot, + mmu_idx, TARGET_PAGE_SIZE); + qemu_log_mask(CPU_LOG_MMU, + "%s address=%" VADDR_PRIx " physical " TARGET_FMT_plx + " prot %d\n", __func__, address, physical, prot); + return true; + } else { + qemu_log_mask(CPU_LOG_MMU, + "%s address=%" VADDR_PRIx " ret %d\n", __func__, address, + ret); + } + if (probe) { + return false; + } + raise_mmu_exception(env, address, access_type, ret); + cpu_loop_exit_restore(cs, retaddr); +} |