1 /* 2 * This program is free software; you can redistribute it and/or modify 3 * it under the terms of the GNU General Public License, version 2, as 4 * published by the Free Software Foundation. 5 * 6 * This program is distributed in the hope that it will be useful, 7 * but WITHOUT ANY WARRANTY; without even the implied warranty of 8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 9 * GNU General Public License for more details. 10 * 11 * You should have received a copy of the GNU General Public License 12 * along with this program; if not, write to the Free Software 13 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 14 * 15 * Copyright IBM Corp. 2007 16 * Copyright 2011 Freescale Semiconductor, Inc. 17 * 18 * Authors: Hollis Blanchard <hollisb@us.ibm.com> 19 */ 20 21 #include <linux/jiffies.h> 22 #include <linux/hrtimer.h> 23 #include <linux/types.h> 24 #include <linux/string.h> 25 #include <linux/kvm_host.h> 26 #include <linux/clockchips.h> 27 28 #include <asm/reg.h> 29 #include <asm/time.h> 30 #include <asm/byteorder.h> 31 #include <asm/kvm_ppc.h> 32 #include <asm/disassemble.h> 33 #include <asm/ppc-opcode.h> 34 #include "timing.h" 35 #include "trace.h" 36 37 void kvmppc_emulate_dec(struct kvm_vcpu *vcpu) 38 { 39 unsigned long dec_nsec; 40 unsigned long long dec_time; 41 42 pr_debug("mtDEC: %x\n", vcpu->arch.dec); 43 hrtimer_try_to_cancel(&vcpu->arch.dec_timer); 44 45 #ifdef CONFIG_PPC_BOOK3S 46 /* mtdec lowers the interrupt line when positive. */ 47 kvmppc_core_dequeue_dec(vcpu); 48 49 /* POWER4+ triggers a dec interrupt if the value is < 0 */ 50 if (vcpu->arch.dec & 0x80000000) { 51 kvmppc_core_queue_dec(vcpu); 52 return; 53 } 54 #endif 55 56 #ifdef CONFIG_BOOKE 57 /* On BOOKE, DEC = 0 is as good as decrementer not enabled */ 58 if (vcpu->arch.dec == 0) 59 return; 60 #endif 61 62 /* 63 * The decrementer ticks at the same rate as the timebase, so 64 * that's how we convert the guest DEC value to the number of 65 * host ticks. 66 */ 67 68 dec_time = vcpu->arch.dec; 69 /* 70 * Guest timebase ticks at the same frequency as host decrementer. 71 * So use the host decrementer calculations for decrementer emulation. 72 */ 73 dec_time = dec_time << decrementer_clockevent.shift; 74 do_div(dec_time, decrementer_clockevent.mult); 75 dec_nsec = do_div(dec_time, NSEC_PER_SEC); 76 hrtimer_start(&vcpu->arch.dec_timer, 77 ktime_set(dec_time, dec_nsec), HRTIMER_MODE_REL); 78 vcpu->arch.dec_jiffies = get_tb(); 79 } 80 81 u32 kvmppc_get_dec(struct kvm_vcpu *vcpu, u64 tb) 82 { 83 u64 jd = tb - vcpu->arch.dec_jiffies; 84 85 #ifdef CONFIG_BOOKE 86 if (vcpu->arch.dec < jd) 87 return 0; 88 #endif 89 90 return vcpu->arch.dec - jd; 91 } 92 93 static int kvmppc_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs) 94 { 95 enum emulation_result emulated = EMULATE_DONE; 96 ulong spr_val = kvmppc_get_gpr(vcpu, rs); 97 98 switch (sprn) { 99 case SPRN_SRR0: 100 vcpu->arch.shared->srr0 = spr_val; 101 break; 102 case SPRN_SRR1: 103 vcpu->arch.shared->srr1 = spr_val; 104 break; 105 106 /* XXX We need to context-switch the timebase for 107 * watchdog and FIT. */ 108 case SPRN_TBWL: break; 109 case SPRN_TBWU: break; 110 111 case SPRN_DEC: 112 vcpu->arch.dec = spr_val; 113 kvmppc_emulate_dec(vcpu); 114 break; 115 116 case SPRN_SPRG0: 117 vcpu->arch.shared->sprg0 = spr_val; 118 break; 119 case SPRN_SPRG1: 120 vcpu->arch.shared->sprg1 = spr_val; 121 break; 122 case SPRN_SPRG2: 123 vcpu->arch.shared->sprg2 = spr_val; 124 break; 125 case SPRN_SPRG3: 126 vcpu->arch.shared->sprg3 = spr_val; 127 break; 128 129 /* PIR can legally be written, but we ignore it */ 130 case SPRN_PIR: break; 131 132 default: 133 emulated = kvmppc_core_emulate_mtspr(vcpu, sprn, 134 spr_val); 135 if (emulated == EMULATE_FAIL) 136 printk(KERN_INFO "mtspr: unknown spr " 137 "0x%x\n", sprn); 138 break; 139 } 140 141 kvmppc_set_exit_type(vcpu, EMULATED_MTSPR_EXITS); 142 143 return emulated; 144 } 145 146 static int kvmppc_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt) 147 { 148 enum emulation_result emulated = EMULATE_DONE; 149 ulong spr_val = 0; 150 151 switch (sprn) { 152 case SPRN_SRR0: 153 spr_val = vcpu->arch.shared->srr0; 154 break; 155 case SPRN_SRR1: 156 spr_val = vcpu->arch.shared->srr1; 157 break; 158 case SPRN_PVR: 159 spr_val = vcpu->arch.pvr; 160 break; 161 case SPRN_PIR: 162 spr_val = vcpu->vcpu_id; 163 break; 164 165 /* Note: mftb and TBRL/TBWL are user-accessible, so 166 * the guest can always access the real TB anyways. 167 * In fact, we probably will never see these traps. */ 168 case SPRN_TBWL: 169 spr_val = get_tb() >> 32; 170 break; 171 case SPRN_TBWU: 172 spr_val = get_tb(); 173 break; 174 175 case SPRN_SPRG0: 176 spr_val = vcpu->arch.shared->sprg0; 177 break; 178 case SPRN_SPRG1: 179 spr_val = vcpu->arch.shared->sprg1; 180 break; 181 case SPRN_SPRG2: 182 spr_val = vcpu->arch.shared->sprg2; 183 break; 184 case SPRN_SPRG3: 185 spr_val = vcpu->arch.shared->sprg3; 186 break; 187 /* Note: SPRG4-7 are user-readable, so we don't get 188 * a trap. */ 189 190 case SPRN_DEC: 191 spr_val = kvmppc_get_dec(vcpu, get_tb()); 192 break; 193 default: 194 emulated = kvmppc_core_emulate_mfspr(vcpu, sprn, 195 &spr_val); 196 if (unlikely(emulated == EMULATE_FAIL)) { 197 printk(KERN_INFO "mfspr: unknown spr " 198 "0x%x\n", sprn); 199 } 200 break; 201 } 202 203 if (emulated == EMULATE_DONE) 204 kvmppc_set_gpr(vcpu, rt, spr_val); 205 kvmppc_set_exit_type(vcpu, EMULATED_MFSPR_EXITS); 206 207 return emulated; 208 } 209 210 /* XXX to do: 211 * lhax 212 * lhaux 213 * lswx 214 * lswi 215 * stswx 216 * stswi 217 * lha 218 * lhau 219 * lmw 220 * stmw 221 * 222 * XXX is_bigendian should depend on MMU mapping or MSR[LE] 223 */ 224 /* XXX Should probably auto-generate instruction decoding for a particular core 225 * from opcode tables in the future. */ 226 int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) 227 { 228 u32 inst = kvmppc_get_last_inst(vcpu); 229 int ra = get_ra(inst); 230 int rs = get_rs(inst); 231 int rt = get_rt(inst); 232 int sprn = get_sprn(inst); 233 enum emulation_result emulated = EMULATE_DONE; 234 int advance = 1; 235 236 /* this default type might be overwritten by subcategories */ 237 kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS); 238 239 pr_debug("Emulating opcode %d / %d\n", get_op(inst), get_xop(inst)); 240 241 switch (get_op(inst)) { 242 case OP_TRAP: 243 #ifdef CONFIG_PPC_BOOK3S 244 case OP_TRAP_64: 245 kvmppc_core_queue_program(vcpu, SRR1_PROGTRAP); 246 #else 247 kvmppc_core_queue_program(vcpu, 248 vcpu->arch.shared->esr | ESR_PTR); 249 #endif 250 advance = 0; 251 break; 252 253 case 31: 254 switch (get_xop(inst)) { 255 256 case OP_31_XOP_TRAP: 257 #ifdef CONFIG_64BIT 258 case OP_31_XOP_TRAP_64: 259 #endif 260 #ifdef CONFIG_PPC_BOOK3S 261 kvmppc_core_queue_program(vcpu, SRR1_PROGTRAP); 262 #else 263 kvmppc_core_queue_program(vcpu, 264 vcpu->arch.shared->esr | ESR_PTR); 265 #endif 266 advance = 0; 267 break; 268 case OP_31_XOP_LWZX: 269 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1); 270 break; 271 272 case OP_31_XOP_LBZX: 273 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1); 274 break; 275 276 case OP_31_XOP_LBZUX: 277 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1); 278 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 279 break; 280 281 case OP_31_XOP_STWX: 282 emulated = kvmppc_handle_store(run, vcpu, 283 kvmppc_get_gpr(vcpu, rs), 284 4, 1); 285 break; 286 287 case OP_31_XOP_STBX: 288 emulated = kvmppc_handle_store(run, vcpu, 289 kvmppc_get_gpr(vcpu, rs), 290 1, 1); 291 break; 292 293 case OP_31_XOP_STBUX: 294 emulated = kvmppc_handle_store(run, vcpu, 295 kvmppc_get_gpr(vcpu, rs), 296 1, 1); 297 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 298 break; 299 300 case OP_31_XOP_LHAX: 301 emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1); 302 break; 303 304 case OP_31_XOP_LHZX: 305 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1); 306 break; 307 308 case OP_31_XOP_LHZUX: 309 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1); 310 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 311 break; 312 313 case OP_31_XOP_MFSPR: 314 emulated = kvmppc_emulate_mfspr(vcpu, sprn, rt); 315 break; 316 317 case OP_31_XOP_STHX: 318 emulated = kvmppc_handle_store(run, vcpu, 319 kvmppc_get_gpr(vcpu, rs), 320 2, 1); 321 break; 322 323 case OP_31_XOP_STHUX: 324 emulated = kvmppc_handle_store(run, vcpu, 325 kvmppc_get_gpr(vcpu, rs), 326 2, 1); 327 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 328 break; 329 330 case OP_31_XOP_MTSPR: 331 emulated = kvmppc_emulate_mtspr(vcpu, sprn, rs); 332 break; 333 334 case OP_31_XOP_DCBST: 335 case OP_31_XOP_DCBF: 336 case OP_31_XOP_DCBI: 337 /* Do nothing. The guest is performing dcbi because 338 * hardware DMA is not snooped by the dcache, but 339 * emulated DMA either goes through the dcache as 340 * normal writes, or the host kernel has handled dcache 341 * coherence. */ 342 break; 343 344 case OP_31_XOP_LWBRX: 345 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 0); 346 break; 347 348 case OP_31_XOP_TLBSYNC: 349 break; 350 351 case OP_31_XOP_STWBRX: 352 emulated = kvmppc_handle_store(run, vcpu, 353 kvmppc_get_gpr(vcpu, rs), 354 4, 0); 355 break; 356 357 case OP_31_XOP_LHBRX: 358 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 0); 359 break; 360 361 case OP_31_XOP_STHBRX: 362 emulated = kvmppc_handle_store(run, vcpu, 363 kvmppc_get_gpr(vcpu, rs), 364 2, 0); 365 break; 366 367 default: 368 /* Attempt core-specific emulation below. */ 369 emulated = EMULATE_FAIL; 370 } 371 break; 372 373 case OP_LWZ: 374 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1); 375 break; 376 377 /* TBD: Add support for other 64 bit load variants like ldu, ldux, ldx etc. */ 378 case OP_LD: 379 rt = get_rt(inst); 380 emulated = kvmppc_handle_load(run, vcpu, rt, 8, 1); 381 break; 382 383 case OP_LWZU: 384 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1); 385 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 386 break; 387 388 case OP_LBZ: 389 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1); 390 break; 391 392 case OP_LBZU: 393 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1); 394 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 395 break; 396 397 case OP_STW: 398 emulated = kvmppc_handle_store(run, vcpu, 399 kvmppc_get_gpr(vcpu, rs), 400 4, 1); 401 break; 402 403 /* TBD: Add support for other 64 bit store variants like stdu, stdux, stdx etc. */ 404 case OP_STD: 405 rs = get_rs(inst); 406 emulated = kvmppc_handle_store(run, vcpu, 407 kvmppc_get_gpr(vcpu, rs), 408 8, 1); 409 break; 410 411 case OP_STWU: 412 emulated = kvmppc_handle_store(run, vcpu, 413 kvmppc_get_gpr(vcpu, rs), 414 4, 1); 415 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 416 break; 417 418 case OP_STB: 419 emulated = kvmppc_handle_store(run, vcpu, 420 kvmppc_get_gpr(vcpu, rs), 421 1, 1); 422 break; 423 424 case OP_STBU: 425 emulated = kvmppc_handle_store(run, vcpu, 426 kvmppc_get_gpr(vcpu, rs), 427 1, 1); 428 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 429 break; 430 431 case OP_LHZ: 432 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1); 433 break; 434 435 case OP_LHZU: 436 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1); 437 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 438 break; 439 440 case OP_LHA: 441 emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1); 442 break; 443 444 case OP_LHAU: 445 emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1); 446 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 447 break; 448 449 case OP_STH: 450 emulated = kvmppc_handle_store(run, vcpu, 451 kvmppc_get_gpr(vcpu, rs), 452 2, 1); 453 break; 454 455 case OP_STHU: 456 emulated = kvmppc_handle_store(run, vcpu, 457 kvmppc_get_gpr(vcpu, rs), 458 2, 1); 459 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 460 break; 461 462 default: 463 emulated = EMULATE_FAIL; 464 } 465 466 if (emulated == EMULATE_FAIL) { 467 emulated = kvmppc_core_emulate_op(run, vcpu, inst, &advance); 468 if (emulated == EMULATE_AGAIN) { 469 advance = 0; 470 } else if (emulated == EMULATE_FAIL) { 471 advance = 0; 472 printk(KERN_ERR "Couldn't emulate instruction 0x%08x " 473 "(op %d xop %d)\n", inst, get_op(inst), get_xop(inst)); 474 kvmppc_core_queue_program(vcpu, 0); 475 } 476 } 477 478 trace_kvm_ppc_instr(inst, kvmppc_get_pc(vcpu), emulated); 479 480 /* Advance past emulated instruction. */ 481 if (advance) 482 kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) + 4); 483 484 return emulated; 485 } 486