1 /* 2 * MIPS TLB (Translation lookaside buffer) helpers. 3 * 4 * Copyright (c) 2004-2005 Jocelyn Mayer 5 * 6 * This library is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Lesser General Public 8 * License as published by the Free Software Foundation; either 9 * version 2.1 of the License, or (at your option) any later version. 10 * 11 * This library is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with this library; if not, see <http://www.gnu.org/licenses/>. 18 */ 19 #include "qemu/osdep.h" 20 #include "cpu.h" 21 #include "exec/exec-all.h" 22 #include "exec/page-protection.h" 23 #include "../internal.h" 24 25 static int is_seg_am_mapped(unsigned int am, bool eu, int mmu_idx) 26 { 27 /* 28 * Interpret access control mode and mmu_idx. 29 * AdE? TLB? 30 * AM K S U E K S U E 31 * UK 0 0 1 1 0 0 - - 0 32 * MK 1 0 1 1 0 1 - - !eu 33 * MSK 2 0 0 1 0 1 1 - !eu 34 * MUSK 3 0 0 0 0 1 1 1 !eu 35 * MUSUK 4 0 0 0 0 0 1 1 0 36 * USK 5 0 0 1 0 0 0 - 0 37 * - 6 - - - - - - - - 38 * UUSK 7 0 0 0 0 0 0 0 0 39 */ 40 int32_t adetlb_mask; 41 42 switch (mmu_idx) { 43 case 3: /* ERL */ 44 /* If EU is set, always unmapped */ 45 if (eu) { 46 return 0; 47 } 48 /* fall through */ 49 case MIPS_HFLAG_KM: 50 /* Never AdE, TLB mapped if AM={1,2,3} */ 51 adetlb_mask = 0x70000000; 52 goto check_tlb; 53 54 case MIPS_HFLAG_SM: 55 /* AdE if AM={0,1}, TLB mapped if AM={2,3,4} */ 56 adetlb_mask = 0xc0380000; 57 goto check_ade; 58 59 case MIPS_HFLAG_UM: 60 /* AdE if AM={0,1,2,5}, TLB mapped if AM={3,4} */ 61 adetlb_mask = 0xe4180000; 62 /* fall through */ 63 check_ade: 64 /* does this AM cause AdE in current execution mode */ 65 if ((adetlb_mask << am) < 0) { 66 return TLBRET_BADADDR; 67 } 68 adetlb_mask <<= 8; 69 /* fall through */ 70 check_tlb: 71 /* is this AM mapped in current execution mode */ 72 return ((adetlb_mask << am) < 0); 73 default: 74 g_assert_not_reached(); 75 }; 76 } 77 78 static int get_seg_physical_address(CPUMIPSState *env, hwaddr *physical, 79 int *prot, target_ulong real_address, 80 MMUAccessType access_type, int mmu_idx, 81 unsigned int am, bool eu, 82 target_ulong segmask, 83 hwaddr physical_base) 84 { 85 int mapped = is_seg_am_mapped(am, eu, mmu_idx); 86 87 if (mapped < 0) { 88 /* is_seg_am_mapped can report TLBRET_BADADDR */ 89 return mapped; 90 } else if (mapped) { 91 /* The segment is TLB mapped */ 92 return env->tlb->map_address(env, physical, prot, real_address, 93 access_type); 94 } else { 95 /* The segment is unmapped */ 96 *physical = physical_base | (real_address & segmask); 97 *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; 98 return TLBRET_MATCH; 99 } 100 } 101 102 static int get_segctl_physical_address(CPUMIPSState *env, hwaddr *physical, 103 int *prot, target_ulong real_address, 104 MMUAccessType access_type, int mmu_idx, 105 uint16_t segctl, target_ulong segmask) 106 { 107 unsigned int am = (segctl & CP0SC_AM_MASK) >> CP0SC_AM; 108 bool eu = (segctl >> CP0SC_EU) & 1; 109 hwaddr pa = ((hwaddr)segctl & CP0SC_PA_MASK) << 20; 110 111 return get_seg_physical_address(env, physical, prot, real_address, 112 access_type, mmu_idx, am, eu, segmask, 113 pa & ~(hwaddr)segmask); 114 } 115 116 int get_physical_address(CPUMIPSState *env, hwaddr *physical, 117 int *prot, target_ulong real_address, 118 MMUAccessType access_type, int mmu_idx) 119 { 120 /* User mode can only access useg/xuseg */ 121 #if defined(TARGET_MIPS64) 122 int user_mode = mmu_idx == MIPS_HFLAG_UM; 123 int supervisor_mode = mmu_idx == MIPS_HFLAG_SM; 124 int kernel_mode = !user_mode && !supervisor_mode; 125 int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0; 126 int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0; 127 int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0; 128 #endif 129 int ret = TLBRET_MATCH; 130 /* effective address (modified for KVM T&E kernel segments) */ 131 target_ulong address = real_address; 132 133 if (address <= USEG_LIMIT) { 134 /* useg */ 135 uint16_t segctl; 136 137 if (address >= 0x40000000UL) { 138 segctl = env->CP0_SegCtl2; 139 } else { 140 segctl = env->CP0_SegCtl2 >> 16; 141 } 142 ret = get_segctl_physical_address(env, physical, prot, 143 real_address, access_type, 144 mmu_idx, segctl, 0x3FFFFFFF); 145 #if defined(TARGET_MIPS64) 146 } else if (address < 0x4000000000000000ULL) { 147 /* xuseg */ 148 if (UX && address <= (0x3FFFFFFFFFFFFFFFULL & env->SEGMask)) { 149 ret = env->tlb->map_address(env, physical, prot, 150 real_address, access_type); 151 } else { 152 ret = TLBRET_BADADDR; 153 } 154 } else if (address < 0x8000000000000000ULL) { 155 /* xsseg */ 156 if ((supervisor_mode || kernel_mode) && 157 SX && address <= (0x7FFFFFFFFFFFFFFFULL & env->SEGMask)) { 158 ret = env->tlb->map_address(env, physical, prot, 159 real_address, access_type); 160 } else { 161 ret = TLBRET_BADADDR; 162 } 163 } else if (address < 0xC000000000000000ULL) { 164 /* xkphys */ 165 if ((address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) { 166 /* KX/SX/UX bit to check for each xkphys EVA access mode */ 167 static const uint8_t am_ksux[8] = { 168 [CP0SC_AM_UK] = (1u << CP0St_KX), 169 [CP0SC_AM_MK] = (1u << CP0St_KX), 170 [CP0SC_AM_MSK] = (1u << CP0St_SX), 171 [CP0SC_AM_MUSK] = (1u << CP0St_UX), 172 [CP0SC_AM_MUSUK] = (1u << CP0St_UX), 173 [CP0SC_AM_USK] = (1u << CP0St_SX), 174 [6] = (1u << CP0St_KX), 175 [CP0SC_AM_UUSK] = (1u << CP0St_UX), 176 }; 177 unsigned int am = CP0SC_AM_UK; 178 unsigned int xr = (env->CP0_SegCtl2 & CP0SC2_XR_MASK) >> CP0SC2_XR; 179 180 if (xr & (1 << ((address >> 59) & 0x7))) { 181 am = (env->CP0_SegCtl1 & CP0SC1_XAM_MASK) >> CP0SC1_XAM; 182 } 183 /* Does CP0_Status.KX/SX/UX permit the access mode (am) */ 184 if (env->CP0_Status & am_ksux[am]) { 185 ret = get_seg_physical_address(env, physical, prot, 186 real_address, access_type, 187 mmu_idx, am, false, env->PAMask, 188 0); 189 } else { 190 ret = TLBRET_BADADDR; 191 } 192 } else { 193 ret = TLBRET_BADADDR; 194 } 195 } else if (address < 0xFFFFFFFF80000000ULL) { 196 /* xkseg */ 197 if (kernel_mode && KX && 198 address <= (0xFFFFFFFF7FFFFFFFULL & env->SEGMask)) { 199 ret = env->tlb->map_address(env, physical, prot, 200 real_address, access_type); 201 } else { 202 ret = TLBRET_BADADDR; 203 } 204 #endif 205 } else if (address < KSEG1_BASE) { 206 /* kseg0 */ 207 ret = get_segctl_physical_address(env, physical, prot, real_address, 208 access_type, mmu_idx, 209 env->CP0_SegCtl1 >> 16, 0x1FFFFFFF); 210 } else if (address < KSEG2_BASE) { 211 /* kseg1 */ 212 ret = get_segctl_physical_address(env, physical, prot, real_address, 213 access_type, mmu_idx, 214 env->CP0_SegCtl1, 0x1FFFFFFF); 215 } else if (address < KSEG3_BASE) { 216 /* sseg (kseg2) */ 217 ret = get_segctl_physical_address(env, physical, prot, real_address, 218 access_type, mmu_idx, 219 env->CP0_SegCtl0 >> 16, 0x1FFFFFFF); 220 } else { 221 /* 222 * kseg3 223 * XXX: debug segment is not emulated 224 */ 225 ret = get_segctl_physical_address(env, physical, prot, real_address, 226 access_type, mmu_idx, 227 env->CP0_SegCtl0, 0x1FFFFFFF); 228 } 229 return ret; 230 } 231 232 hwaddr mips_cpu_get_phys_page_debug(CPUState *cs, vaddr addr) 233 { 234 CPUMIPSState *env = cpu_env(cs); 235 hwaddr phys_addr; 236 int prot; 237 238 if (get_physical_address(env, &phys_addr, &prot, addr, MMU_DATA_LOAD, 239 mips_env_mmu_index(env)) != 0) { 240 return -1; 241 } 242 return phys_addr; 243 } 244