blob: 580362ac3e9ffbe6c8523cf57902dcda018ceed5 [file] [log] [blame]
/* 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"
#ifdef CONFIG_TCG
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;
}
#else
static int loongarch_map_address(CPULoongArchState *env, hwaddr *physical,
int *prot, target_ulong address,
MMUAccessType access_type, int mmu_idx)
{
return TLBRET_NOMATCH;
}
#endif
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_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);
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)
{
CPULoongArchState *env = cpu_env(cs);
hwaddr phys_addr;
int prot;
if (get_physical_address(env, &phys_addr, &prot, addr, MMU_DATA_LOAD,
cpu_mmu_index(cs, false)) != 0) {
return -1;
}
return phys_addr;
}