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 "../internal.h" 23 24 static int is_seg_am_mapped(unsigned int am, bool eu, int mmu_idx) 25 { 26 /* 27 * Interpret access control mode and mmu_idx. 28 * AdE? TLB? 29 * AM K S U E K S U E 30 * UK 0 0 1 1 0 0 - - 0 31 * MK 1 0 1 1 0 1 - - !eu 32 * MSK 2 0 0 1 0 1 1 - !eu 33 * MUSK 3 0 0 0 0 1 1 1 !eu 34 * MUSUK 4 0 0 0 0 0 1 1 0 35 * USK 5 0 0 1 0 0 0 - 0 36 * - 6 - - - - - - - - 37 * UUSK 7 0 0 0 0 0 0 0 0 38 */ 39 int32_t adetlb_mask; 40 41 switch (mmu_idx) { 42 case 3: /* ERL */ 43 /* If EU is set, always unmapped */ 44 if (eu) { 45 return 0; 46 } 47 /* fall through */ 48 case MIPS_HFLAG_KM: 49 /* Never AdE, TLB mapped if AM={1,2,3} */ 50 adetlb_mask = 0x70000000; 51 goto check_tlb; 52 53 case MIPS_HFLAG_SM: 54 /* AdE if AM={0,1}, TLB mapped if AM={2,3,4} */ 55 adetlb_mask = 0xc0380000; 56 goto check_ade; 57 58 case MIPS_HFLAG_UM: 59 /* AdE if AM={0,1,2,5}, TLB mapped if AM={3,4} */ 60 adetlb_mask = 0xe4180000; 61 /* fall through */ 62 check_ade: 63 /* does this AM cause AdE in current execution mode */ 64 if ((adetlb_mask << am) < 0) { 65 return TLBRET_BADADDR; 66 } 67 adetlb_mask <<= 8; 68 /* fall through */ 69 check_tlb: 70 /* is this AM mapped in current execution mode */ 71 return ((adetlb_mask << am) < 0); 72 default: 73 assert(0); 74 return TLBRET_BADADDR; 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 (mips_um_ksegs_enabled()) { 134 /* KVM T&E adds guest kernel segments in useg */ 135 if (real_address >= KVM_KSEG0_BASE) { 136 if (real_address < KVM_KSEG2_BASE) { 137 /* kseg0 */ 138 address += KSEG0_BASE - KVM_KSEG0_BASE; 139 } else if (real_address <= USEG_LIMIT) { 140 /* kseg2/3 */ 141 address += KSEG2_BASE - KVM_KSEG2_BASE; 142 } 143 } 144 } 145 146 if (address <= USEG_LIMIT) { 147 /* useg */ 148 uint16_t segctl; 149 150 if (address >= 0x40000000UL) { 151 segctl = env->CP0_SegCtl2; 152 } else { 153 segctl = env->CP0_SegCtl2 >> 16; 154 } 155 ret = get_segctl_physical_address(env, physical, prot, 156 real_address, access_type, 157 mmu_idx, segctl, 0x3FFFFFFF); 158 #if defined(TARGET_MIPS64) 159 } else if (address < 0x4000000000000000ULL) { 160 /* xuseg */ 161 if (UX && address <= (0x3FFFFFFFFFFFFFFFULL & env->SEGMask)) { 162 ret = env->tlb->map_address(env, physical, prot, 163 real_address, access_type); 164 } else { 165 ret = TLBRET_BADADDR; 166 } 167 } else if (address < 0x8000000000000000ULL) { 168 /* xsseg */ 169 if ((supervisor_mode || kernel_mode) && 170 SX && address <= (0x7FFFFFFFFFFFFFFFULL & env->SEGMask)) { 171 ret = env->tlb->map_address(env, physical, prot, 172 real_address, access_type); 173 } else { 174 ret = TLBRET_BADADDR; 175 } 176 } else if (address < 0xC000000000000000ULL) { 177 /* xkphys */ 178 if ((address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) { 179 /* KX/SX/UX bit to check for each xkphys EVA access mode */ 180 static const uint8_t am_ksux[8] = { 181 [CP0SC_AM_UK] = (1u << CP0St_KX), 182 [CP0SC_AM_MK] = (1u << CP0St_KX), 183 [CP0SC_AM_MSK] = (1u << CP0St_SX), 184 [CP0SC_AM_MUSK] = (1u << CP0St_UX), 185 [CP0SC_AM_MUSUK] = (1u << CP0St_UX), 186 [CP0SC_AM_USK] = (1u << CP0St_SX), 187 [6] = (1u << CP0St_KX), 188 [CP0SC_AM_UUSK] = (1u << CP0St_UX), 189 }; 190 unsigned int am = CP0SC_AM_UK; 191 unsigned int xr = (env->CP0_SegCtl2 & CP0SC2_XR_MASK) >> CP0SC2_XR; 192 193 if (xr & (1 << ((address >> 59) & 0x7))) { 194 am = (env->CP0_SegCtl1 & CP0SC1_XAM_MASK) >> CP0SC1_XAM; 195 } 196 /* Does CP0_Status.KX/SX/UX permit the access mode (am) */ 197 if (env->CP0_Status & am_ksux[am]) { 198 ret = get_seg_physical_address(env, physical, prot, 199 real_address, access_type, 200 mmu_idx, am, false, env->PAMask, 201 0); 202 } else { 203 ret = TLBRET_BADADDR; 204 } 205 } else { 206 ret = TLBRET_BADADDR; 207 } 208 } else if (address < 0xFFFFFFFF80000000ULL) { 209 /* xkseg */ 210 if (kernel_mode && KX && 211 address <= (0xFFFFFFFF7FFFFFFFULL & env->SEGMask)) { 212 ret = env->tlb->map_address(env, physical, prot, 213 real_address, access_type); 214 } else { 215 ret = TLBRET_BADADDR; 216 } 217 #endif 218 } else if (address < KSEG1_BASE) { 219 /* kseg0 */ 220 ret = get_segctl_physical_address(env, physical, prot, real_address, 221 access_type, mmu_idx, 222 env->CP0_SegCtl1 >> 16, 0x1FFFFFFF); 223 } else if (address < KSEG2_BASE) { 224 /* kseg1 */ 225 ret = get_segctl_physical_address(env, physical, prot, real_address, 226 access_type, mmu_idx, 227 env->CP0_SegCtl1, 0x1FFFFFFF); 228 } else if (address < KSEG3_BASE) { 229 /* sseg (kseg2) */ 230 ret = get_segctl_physical_address(env, physical, prot, real_address, 231 access_type, mmu_idx, 232 env->CP0_SegCtl0 >> 16, 0x1FFFFFFF); 233 } else { 234 /* 235 * kseg3 236 * XXX: debug segment is not emulated 237 */ 238 ret = get_segctl_physical_address(env, physical, prot, real_address, 239 access_type, mmu_idx, 240 env->CP0_SegCtl0, 0x1FFFFFFF); 241 } 242 return ret; 243 } 244 245 hwaddr mips_cpu_get_phys_page_debug(CPUState *cs, vaddr addr) 246 { 247 MIPSCPU *cpu = MIPS_CPU(cs); 248 CPUMIPSState *env = &cpu->env; 249 hwaddr phys_addr; 250 int prot; 251 252 if (get_physical_address(env, &phys_addr, &prot, addr, MMU_DATA_LOAD, 253 cpu_mmu_index(env, false)) != 0) { 254 return -1; 255 } 256 return phys_addr; 257 } 258