1 /* 2 * PowerPC Radix MMU mulation helpers for QEMU. 3 * 4 * Copyright (c) 2016 Suraj Jitindar Singh, IBM Corporation 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 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 20 #include "qemu/osdep.h" 21 #include "cpu.h" 22 #include "exec/exec-all.h" 23 #include "exec/helper-proto.h" 24 #include "qemu/error-report.h" 25 #include "sysemu/kvm.h" 26 #include "kvm_ppc.h" 27 #include "exec/log.h" 28 #include "mmu-radix64.h" 29 #include "mmu-book3s-v3.h" 30 31 static bool ppc_radix64_get_fully_qualified_addr(CPUPPCState *env, vaddr eaddr, 32 uint64_t *lpid, uint64_t *pid) 33 { 34 if (msr_hv) { /* MSR[HV] -> Hypervisor/bare metal */ 35 switch (eaddr & R_EADDR_QUADRANT) { 36 case R_EADDR_QUADRANT0: 37 *lpid = 0; 38 *pid = env->spr[SPR_BOOKS_PID]; 39 break; 40 case R_EADDR_QUADRANT1: 41 *lpid = env->spr[SPR_LPIDR]; 42 *pid = env->spr[SPR_BOOKS_PID]; 43 break; 44 case R_EADDR_QUADRANT2: 45 *lpid = env->spr[SPR_LPIDR]; 46 *pid = 0; 47 break; 48 case R_EADDR_QUADRANT3: 49 *lpid = 0; 50 *pid = 0; 51 break; 52 } 53 } else { /* !MSR[HV] -> Guest */ 54 switch (eaddr & R_EADDR_QUADRANT) { 55 case R_EADDR_QUADRANT0: /* Guest application */ 56 *lpid = env->spr[SPR_LPIDR]; 57 *pid = env->spr[SPR_BOOKS_PID]; 58 break; 59 case R_EADDR_QUADRANT1: /* Illegal */ 60 case R_EADDR_QUADRANT2: 61 return false; 62 case R_EADDR_QUADRANT3: /* Guest OS */ 63 *lpid = env->spr[SPR_LPIDR]; 64 *pid = 0; /* pid set to 0 -> addresses guest operating system */ 65 break; 66 } 67 } 68 69 return true; 70 } 71 72 static void ppc_radix64_raise_segi(PowerPCCPU *cpu, int rwx, vaddr eaddr) 73 { 74 CPUState *cs = CPU(cpu); 75 CPUPPCState *env = &cpu->env; 76 77 if (rwx == 2) { /* Instruction Segment Interrupt */ 78 cs->exception_index = POWERPC_EXCP_ISEG; 79 } else { /* Data Segment Interrupt */ 80 cs->exception_index = POWERPC_EXCP_DSEG; 81 env->spr[SPR_DAR] = eaddr; 82 } 83 env->error_code = 0; 84 } 85 86 static void ppc_radix64_raise_si(PowerPCCPU *cpu, int rwx, vaddr eaddr, 87 uint32_t cause) 88 { 89 CPUState *cs = CPU(cpu); 90 CPUPPCState *env = &cpu->env; 91 92 if (rwx == 2) { /* Instruction Storage Interrupt */ 93 cs->exception_index = POWERPC_EXCP_ISI; 94 env->error_code = cause; 95 } else { /* Data Storage Interrupt */ 96 cs->exception_index = POWERPC_EXCP_DSI; 97 if (rwx == 1) { /* Write -> Store */ 98 cause |= DSISR_ISSTORE; 99 } 100 env->spr[SPR_DSISR] = cause; 101 env->spr[SPR_DAR] = eaddr; 102 env->error_code = 0; 103 } 104 } 105 106 107 static bool ppc_radix64_check_prot(PowerPCCPU *cpu, int rwx, uint64_t pte, 108 int *fault_cause, int *prot) 109 { 110 CPUPPCState *env = &cpu->env; 111 const int need_prot[] = { PAGE_READ, PAGE_WRITE, PAGE_EXEC }; 112 113 /* Check Page Attributes (pte58:59) */ 114 if (((pte & R_PTE_ATT) == R_PTE_ATT_NI_IO) && (rwx == 2)) { 115 /* 116 * Radix PTE entries with the non-idempotent I/O attribute are treated 117 * as guarded storage 118 */ 119 *fault_cause |= SRR1_NOEXEC_GUARD; 120 return true; 121 } 122 123 /* Determine permissions allowed by Encoded Access Authority */ 124 if ((pte & R_PTE_EAA_PRIV) && msr_pr) { /* Insufficient Privilege */ 125 *prot = 0; 126 } else if (msr_pr || (pte & R_PTE_EAA_PRIV)) { 127 *prot = ppc_radix64_get_prot_eaa(pte); 128 } else { /* !msr_pr && !(pte & R_PTE_EAA_PRIV) */ 129 *prot = ppc_radix64_get_prot_eaa(pte); 130 *prot &= ppc_radix64_get_prot_amr(cpu); /* Least combined permissions */ 131 } 132 133 /* Check if requested access type is allowed */ 134 if (need_prot[rwx] & ~(*prot)) { /* Page Protected for that Access */ 135 *fault_cause |= DSISR_PROTFAULT; 136 return true; 137 } 138 139 return false; 140 } 141 142 static void ppc_radix64_set_rc(PowerPCCPU *cpu, int rwx, uint64_t pte, 143 hwaddr pte_addr, int *prot) 144 { 145 CPUState *cs = CPU(cpu); 146 uint64_t npte; 147 148 npte = pte | R_PTE_R; /* Always set reference bit */ 149 150 if (rwx == 1) { /* Store/Write */ 151 npte |= R_PTE_C; /* Set change bit */ 152 } else { 153 /* 154 * Treat the page as read-only for now, so that a later write 155 * will pass through this function again to set the C bit. 156 */ 157 *prot &= ~PAGE_WRITE; 158 } 159 160 if (pte ^ npte) { /* If pte has changed then write it back */ 161 stq_phys(cs->as, pte_addr, npte); 162 } 163 } 164 165 static uint64_t ppc_radix64_walk_tree(PowerPCCPU *cpu, vaddr eaddr, 166 uint64_t base_addr, uint64_t nls, 167 hwaddr *raddr, int *psize, 168 int *fault_cause, hwaddr *pte_addr) 169 { 170 CPUState *cs = CPU(cpu); 171 uint64_t index, pde; 172 173 if (nls < 5) { /* Directory maps less than 2**5 entries */ 174 *fault_cause |= DSISR_R_BADCONFIG; 175 return 0; 176 } 177 178 /* Read page <directory/table> entry from guest address space */ 179 index = eaddr >> (*psize - nls); /* Shift */ 180 index &= ((1UL << nls) - 1); /* Mask */ 181 pde = ldq_phys(cs->as, base_addr + (index * sizeof(pde))); 182 if (!(pde & R_PTE_VALID)) { /* Invalid Entry */ 183 *fault_cause |= DSISR_NOPTE; 184 return 0; 185 } 186 187 *psize -= nls; 188 189 /* Check if Leaf Entry -> Page Table Entry -> Stop the Search */ 190 if (pde & R_PTE_LEAF) { 191 uint64_t rpn = pde & R_PTE_RPN; 192 uint64_t mask = (1UL << *psize) - 1; 193 194 /* Or high bits of rpn and low bits to ea to form whole real addr */ 195 *raddr = (rpn & ~mask) | (eaddr & mask); 196 *pte_addr = base_addr + (index * sizeof(pde)); 197 return pde; 198 } 199 200 /* Next Level of Radix Tree */ 201 return ppc_radix64_walk_tree(cpu, eaddr, pde & R_PDE_NLB, pde & R_PDE_NLS, 202 raddr, psize, fault_cause, pte_addr); 203 } 204 205 static bool validate_pate(PowerPCCPU *cpu, uint64_t lpid, ppc_v3_pate_t *pate) 206 { 207 CPUPPCState *env = &cpu->env; 208 209 if (!(pate->dw0 & PATE0_HR)) { 210 return false; 211 } 212 if (lpid == 0 && !msr_hv) { 213 return false; 214 } 215 /* More checks ... */ 216 return true; 217 } 218 219 int ppc_radix64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr, int rwx, 220 int mmu_idx) 221 { 222 CPUState *cs = CPU(cpu); 223 CPUPPCState *env = &cpu->env; 224 PPCVirtualHypervisorClass *vhc; 225 hwaddr raddr, pte_addr; 226 uint64_t lpid = 0, pid = 0, offset, size, prtbe0, pte; 227 int page_size, prot, fault_cause = 0; 228 ppc_v3_pate_t pate; 229 230 assert((rwx == 0) || (rwx == 1) || (rwx == 2)); 231 assert(ppc64_use_proc_tbl(cpu)); 232 233 /* Real Mode Access */ 234 if (((rwx == 2) && (msr_ir == 0)) || ((rwx != 2) && (msr_dr == 0))) { 235 /* In real mode top 4 effective addr bits (mostly) ignored */ 236 raddr = eaddr & 0x0FFFFFFFFFFFFFFFULL; 237 238 tlb_set_page(cs, eaddr & TARGET_PAGE_MASK, raddr & TARGET_PAGE_MASK, 239 PAGE_READ | PAGE_WRITE | PAGE_EXEC, mmu_idx, 240 TARGET_PAGE_SIZE); 241 return 0; 242 } 243 244 /* Virtual Mode Access - get the fully qualified address */ 245 if (!ppc_radix64_get_fully_qualified_addr(env, eaddr, &lpid, &pid)) { 246 ppc_radix64_raise_segi(cpu, rwx, eaddr); 247 return 1; 248 } 249 250 /* Get Process Table */ 251 if (cpu->vhyp) { 252 vhc = PPC_VIRTUAL_HYPERVISOR_GET_CLASS(cpu->vhyp); 253 vhc->get_pate(cpu->vhyp, &pate); 254 } else { 255 if (!ppc64_v3_get_pate(cpu, lpid, &pate)) { 256 ppc_radix64_raise_si(cpu, rwx, eaddr, DSISR_NOPTE); 257 return 1; 258 } 259 if (!validate_pate(cpu, lpid, &pate)) { 260 ppc_radix64_raise_si(cpu, rwx, eaddr, DSISR_R_BADCONFIG); 261 } 262 /* We don't support guest mode yet */ 263 if (lpid != 0) { 264 error_report("PowerNV guest support Unimplemented"); 265 exit(1); 266 } 267 } 268 269 /* Index Process Table by PID to Find Corresponding Process Table Entry */ 270 offset = pid * sizeof(struct prtb_entry); 271 size = 1ULL << ((pate.dw1 & PATE1_R_PRTS) + 12); 272 if (offset >= size) { 273 /* offset exceeds size of the process table */ 274 ppc_radix64_raise_si(cpu, rwx, eaddr, DSISR_NOPTE); 275 return 1; 276 } 277 prtbe0 = ldq_phys(cs->as, (pate.dw1 & PATE1_R_PRTB) + offset); 278 279 /* Walk Radix Tree from Process Table Entry to Convert EA to RA */ 280 page_size = PRTBE_R_GET_RTS(prtbe0); 281 pte = ppc_radix64_walk_tree(cpu, eaddr & R_EADDR_MASK, 282 prtbe0 & PRTBE_R_RPDB, prtbe0 & PRTBE_R_RPDS, 283 &raddr, &page_size, &fault_cause, &pte_addr); 284 if (!pte || ppc_radix64_check_prot(cpu, rwx, pte, &fault_cause, &prot)) { 285 /* Couldn't get pte or access denied due to protection */ 286 ppc_radix64_raise_si(cpu, rwx, eaddr, fault_cause); 287 return 1; 288 } 289 290 /* Update Reference and Change Bits */ 291 ppc_radix64_set_rc(cpu, rwx, pte, pte_addr, &prot); 292 293 tlb_set_page(cs, eaddr & TARGET_PAGE_MASK, raddr & TARGET_PAGE_MASK, 294 prot, mmu_idx, 1UL << page_size); 295 return 0; 296 } 297 298 hwaddr ppc_radix64_get_phys_page_debug(PowerPCCPU *cpu, target_ulong eaddr) 299 { 300 CPUState *cs = CPU(cpu); 301 CPUPPCState *env = &cpu->env; 302 PPCVirtualHypervisorClass *vhc; 303 hwaddr raddr, pte_addr; 304 uint64_t lpid = 0, pid = 0, offset, size, prtbe0, pte; 305 int page_size, fault_cause = 0; 306 ppc_v3_pate_t pate; 307 308 /* Handle Real Mode */ 309 if (msr_dr == 0) { 310 /* In real mode top 4 effective addr bits (mostly) ignored */ 311 return eaddr & 0x0FFFFFFFFFFFFFFFULL; 312 } 313 314 /* Virtual Mode Access - get the fully qualified address */ 315 if (!ppc_radix64_get_fully_qualified_addr(env, eaddr, &lpid, &pid)) { 316 return -1; 317 } 318 319 /* Get Process Table */ 320 if (cpu->vhyp) { 321 vhc = PPC_VIRTUAL_HYPERVISOR_GET_CLASS(cpu->vhyp); 322 vhc->get_pate(cpu->vhyp, &pate); 323 } else { 324 if (!ppc64_v3_get_pate(cpu, lpid, &pate)) { 325 return -1; 326 } 327 if (!validate_pate(cpu, lpid, &pate)) { 328 return -1; 329 } 330 /* We don't support guest mode yet */ 331 if (lpid != 0) { 332 error_report("PowerNV guest support Unimplemented"); 333 exit(1); 334 } 335 } 336 337 /* Index Process Table by PID to Find Corresponding Process Table Entry */ 338 offset = pid * sizeof(struct prtb_entry); 339 size = 1ULL << ((pate.dw1 & PATE1_R_PRTS) + 12); 340 if (offset >= size) { 341 /* offset exceeds size of the process table */ 342 return -1; 343 } 344 prtbe0 = ldq_phys(cs->as, (pate.dw1 & PATE1_R_PRTB) + offset); 345 346 /* Walk Radix Tree from Process Table Entry to Convert EA to RA */ 347 page_size = PRTBE_R_GET_RTS(prtbe0); 348 pte = ppc_radix64_walk_tree(cpu, eaddr & R_EADDR_MASK, 349 prtbe0 & PRTBE_R_RPDB, prtbe0 & PRTBE_R_RPDS, 350 &raddr, &page_size, &fault_cause, &pte_addr); 351 if (!pte) { 352 return -1; 353 } 354 355 return raddr & TARGET_PAGE_MASK; 356 } 357