blob: 0cc01a0ca47ecead8a00ea420ea18053f3ff3b0e [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 "system/tcg.h"
#include "cpu.h"
#include "accel/tcg/cpu-mmu-index.h"
#include "exec/target_page.h"
#include "internals.h"
#include "cpu-csr.h"
#include "cpu-mmu.h"
#include "tcg/tcg_loongarch.h"
void get_dir_base_width(CPULoongArchState *env, uint64_t *dir_base,
uint64_t *dir_width, target_ulong level)
{
switch (level) {
case 1:
*dir_base = FIELD_EX64(env->CSR_PWCL, CSR_PWCL, DIR1_BASE);
*dir_width = FIELD_EX64(env->CSR_PWCL, CSR_PWCL, DIR1_WIDTH);
break;
case 2:
*dir_base = FIELD_EX64(env->CSR_PWCL, CSR_PWCL, DIR2_BASE);
*dir_width = FIELD_EX64(env->CSR_PWCL, CSR_PWCL, DIR2_WIDTH);
break;
case 3:
*dir_base = FIELD_EX64(env->CSR_PWCH, CSR_PWCH, DIR3_BASE);
*dir_width = FIELD_EX64(env->CSR_PWCH, CSR_PWCH, DIR3_WIDTH);
break;
case 4:
*dir_base = FIELD_EX64(env->CSR_PWCH, CSR_PWCH, DIR4_BASE);
*dir_width = FIELD_EX64(env->CSR_PWCH, CSR_PWCH, DIR4_WIDTH);
break;
default:
/* level may be zero for ldpte */
*dir_base = FIELD_EX64(env->CSR_PWCL, CSR_PWCL, PTBASE);
*dir_width = FIELD_EX64(env->CSR_PWCL, CSR_PWCL, PTWIDTH);
break;
}
}
TLBRet loongarch_check_pte(CPULoongArchState *env, MMUContext *context,
MMUAccessType access_type, int mmu_idx)
{
uint64_t plv = mmu_idx;
uint64_t tlb_entry, tlb_ppn;
uint8_t tlb_ps, tlb_v, tlb_d, tlb_plv, tlb_nx, tlb_nr, tlb_rplv;
tlb_entry = context->pte;
tlb_ps = context->ps;
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;
}
context->physical = (tlb_ppn << R_TLBENTRY_64_PPN_SHIFT) |
(context->addr & MAKE_64BIT_MASK(0, tlb_ps));
context->prot = PAGE_READ;
if (tlb_d) {
context->prot |= PAGE_WRITE;
}
if (!tlb_nx) {
context->prot |= PAGE_EXEC;
}
return TLBRET_MATCH;
}
static TLBRet loongarch_page_table_walker(CPULoongArchState *env,
MMUContext *context,
int access_type, int mmu_idx)
{
CPUState *cs = env_cpu(env);
target_ulong index, phys;
uint64_t dir_base, dir_width;
uint64_t base;
int level;
vaddr address;
address = context->addr;
if ((address >> 63) & 0x1) {
base = env->CSR_PGDH;
} else {
base = env->CSR_PGDL;
}
base &= TARGET_PHYS_MASK;
for (level = 4; level > 0; level--) {
get_dir_base_width(env, &dir_base, &dir_width, level);
if (dir_width == 0) {
continue;
}
/* get next level page directory */
index = (address >> dir_base) & ((1 << dir_width) - 1);
phys = base | index << 3;
base = ldq_phys(cs->as, phys) & TARGET_PHYS_MASK;
if (FIELD_EX64(base, TLBENTRY, HUGE)) {
/* base is a huge pte */
break;
}
}
/* pte */
if (FIELD_EX64(base, TLBENTRY, HUGE)) {
/* Huge Page. base is pte */
base = FIELD_DP64(base, TLBENTRY, LEVEL, 0);
base = FIELD_DP64(base, TLBENTRY, HUGE, 0);
if (FIELD_EX64(base, TLBENTRY, HGLOBAL)) {
base = FIELD_DP64(base, TLBENTRY, HGLOBAL, 0);
base = FIELD_DP64(base, TLBENTRY, G, 1);
}
} else {
/* Normal Page. base points to pte */
get_dir_base_width(env, &dir_base, &dir_width, 0);
index = (address >> dir_base) & ((1 << dir_width) - 1);
phys = base | index << 3;
base = ldq_phys(cs->as, phys);
}
context->ps = dir_base;
context->pte = base;
return loongarch_check_pte(env, context, access_type, mmu_idx);
}
static TLBRet loongarch_map_address(CPULoongArchState *env, hwaddr *physical,
int *prot, vaddr address,
MMUAccessType access_type, int mmu_idx,
int is_debug)
{
TLBRet ret;
MMUContext context;
context.addr = address;
if (tcg_enabled()) {
ret = loongarch_get_addr_from_tlb(env, &context, access_type, mmu_idx);
if (ret != TLBRET_NOMATCH) {
if (ret == TLBRET_MATCH) {
*physical = context.physical;
*prot = context.prot;
}
return ret;
}
}
if (is_debug) {
/*
* For debugger memory access, we want to do the map when there is a
* legal mapping, even if the mapping is not yet in TLB. return 0 if
* there is a valid map, else none zero.
*/
ret = loongarch_page_table_walker(env, &context, access_type, mmu_idx);
if (ret == TLBRET_MATCH) {
*physical = context.physical;
*prot = context.prot;
}
return ret;
}
return TLBRET_NOMATCH;
}
static hwaddr dmw_va2pa(CPULoongArchState *env, vaddr 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);
}
}
TLBRet get_physical_address(CPULoongArchState *env, hwaddr *physical,
int *prot, vaddr address,
MMUAccessType access_type, int mmu_idx,
int is_debug)
{
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 = (int64_t)address >> (TARGET_VIRT_ADDR_SPACE_BITS - 1);
if (!(addr_high == 0 || addr_high == -1ULL)) {
return TLBRET_BADADDR;
}
/* Mapped address */
return loongarch_map_address(env, physical, prot, address,
access_type, mmu_idx, is_debug);
}
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), 1) != TLBRET_MATCH) {
return -1;
}
return phys_addr;
}