--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * LoongArch CPU helpers for qemu
+ *
+ * Copyright (c) 2024 Loongson Technology Corporation Limited
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "internals.h"
+#include "cpu-csr.h"
+
+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);
+ if (is_la64(env)) {
+ tlb_ppn = FIELD_EX64(tlb_entry, TLBENTRY_64, PPN);
+ tlb_nx = FIELD_EX64(tlb_entry, TLBENTRY_64, NX);
+ tlb_nr = FIELD_EX64(tlb_entry, TLBENTRY_64, NR);
+ tlb_rplv = FIELD_EX64(tlb_entry, TLBENTRY_64, RPLV);
+ } else {
+ tlb_ppn = FIELD_EX64(tlb_entry, TLBENTRY_32, PPN);
+ tlb_nx = 0;
+ tlb_nr = 0;
+ tlb_rplv = 0;
+ }
+
+ /* Remove sw bit between bit12 -- bit PS*/
+ tlb_ppn = tlb_ppn & ~(((0x1UL << (tlb_ps - 12)) -1));
+
+ /* 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;
+ }
+
+ *physical = (tlb_ppn << R_TLBENTRY_64_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]
+ */
+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 hwaddr dmw_va2pa(CPULoongArchState *env, target_ulong va,
+ target_ulong dmw)
+{
+ if (is_la64(env)) {
+ return va & TARGET_VIRT_MASK;
+ } else {
+ uint32_t pseg = FIELD_EX32(dmw, CSR_DMW_32, PSEG);
+ return (va & MAKE_64BIT_MASK(0, R_CSR_DMW_32_VSEG_SHIFT)) | \
+ (pseg << R_CSR_DMW_32_VSEG_SHIFT);
+ }
+}
+
+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_IDX_USER;
+ int kernel_mode = mmu_idx == MMU_IDX_KERNEL;
+ 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);
+ if (is_la64(env)) {
+ base_v = address >> R_CSR_DMW_64_VSEG_SHIFT;
+ } else {
+ base_v = address >> R_CSR_DMW_32_VSEG_SHIFT;
+ }
+ /* Check direct map window */
+ for (int i = 0; i < 4; i++) {
+ if (is_la64(env)) {
+ base_c = FIELD_EX64(env->CSR_DMW[i], CSR_DMW_64, VSEG);
+ } else {
+ base_c = FIELD_EX64(env->CSR_DMW[i], CSR_DMW_32, VSEG);
+ }
+ if ((plv & env->CSR_DMW[i]) && (base_c == base_v)) {
+ *physical = dmw_va2pa(env, address, env->CSR_DMW[i]);
+ *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;
+}