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 = vcpu->kvm->arch.kvm_ops->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 = vcpu->kvm->arch.kvm_ops->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 */ 223 /* XXX Should probably auto-generate instruction decoding for a particular core 224 * from opcode tables in the future. */ 225 int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) 226 { 227 u32 inst = kvmppc_get_last_inst(vcpu); 228 int ra = get_ra(inst); 229 int rs = get_rs(inst); 230 int rt = get_rt(inst); 231 int sprn = get_sprn(inst); 232 enum emulation_result emulated = EMULATE_DONE; 233 int advance = 1; 234 235 /* this default type might be overwritten by subcategories */ 236 kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS); 237 238 pr_debug("Emulating opcode %d / %d\n", get_op(inst), get_xop(inst)); 239 240 switch (get_op(inst)) { 241 case OP_TRAP: 242 #ifdef CONFIG_PPC_BOOK3S 243 case OP_TRAP_64: 244 kvmppc_core_queue_program(vcpu, SRR1_PROGTRAP); 245 #else 246 kvmppc_core_queue_program(vcpu, 247 vcpu->arch.shared->esr | ESR_PTR); 248 #endif 249 advance = 0; 250 break; 251 252 case 31: 253 switch (get_xop(inst)) { 254 255 case OP_31_XOP_TRAP: 256 #ifdef CONFIG_64BIT 257 case OP_31_XOP_TRAP_64: 258 #endif 259 #ifdef CONFIG_PPC_BOOK3S 260 kvmppc_core_queue_program(vcpu, SRR1_PROGTRAP); 261 #else 262 kvmppc_core_queue_program(vcpu, 263 vcpu->arch.shared->esr | ESR_PTR); 264 #endif 265 advance = 0; 266 break; 267 case OP_31_XOP_LWZX: 268 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1); 269 break; 270 271 case OP_31_XOP_LBZX: 272 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1); 273 break; 274 275 case OP_31_XOP_LBZUX: 276 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1); 277 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 278 break; 279 280 case OP_31_XOP_STWX: 281 emulated = kvmppc_handle_store(run, vcpu, 282 kvmppc_get_gpr(vcpu, rs), 283 4, 1); 284 break; 285 286 case OP_31_XOP_STBX: 287 emulated = kvmppc_handle_store(run, vcpu, 288 kvmppc_get_gpr(vcpu, rs), 289 1, 1); 290 break; 291 292 case OP_31_XOP_STBUX: 293 emulated = kvmppc_handle_store(run, vcpu, 294 kvmppc_get_gpr(vcpu, rs), 295 1, 1); 296 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 297 break; 298 299 case OP_31_XOP_LHAX: 300 emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1); 301 break; 302 303 case OP_31_XOP_LHZX: 304 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1); 305 break; 306 307 case OP_31_XOP_LHZUX: 308 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1); 309 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 310 break; 311 312 case OP_31_XOP_MFSPR: 313 emulated = kvmppc_emulate_mfspr(vcpu, sprn, rt); 314 break; 315 316 case OP_31_XOP_STHX: 317 emulated = kvmppc_handle_store(run, vcpu, 318 kvmppc_get_gpr(vcpu, rs), 319 2, 1); 320 break; 321 322 case OP_31_XOP_STHUX: 323 emulated = kvmppc_handle_store(run, vcpu, 324 kvmppc_get_gpr(vcpu, rs), 325 2, 1); 326 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 327 break; 328 329 case OP_31_XOP_MTSPR: 330 emulated = kvmppc_emulate_mtspr(vcpu, sprn, rs); 331 break; 332 333 case OP_31_XOP_DCBST: 334 case OP_31_XOP_DCBF: 335 case OP_31_XOP_DCBI: 336 /* Do nothing. The guest is performing dcbi because 337 * hardware DMA is not snooped by the dcache, but 338 * emulated DMA either goes through the dcache as 339 * normal writes, or the host kernel has handled dcache 340 * coherence. */ 341 break; 342 343 case OP_31_XOP_LWBRX: 344 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 0); 345 break; 346 347 case OP_31_XOP_TLBSYNC: 348 break; 349 350 case OP_31_XOP_STWBRX: 351 emulated = kvmppc_handle_store(run, vcpu, 352 kvmppc_get_gpr(vcpu, rs), 353 4, 0); 354 break; 355 356 case OP_31_XOP_LHBRX: 357 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 0); 358 break; 359 360 case OP_31_XOP_STHBRX: 361 emulated = kvmppc_handle_store(run, vcpu, 362 kvmppc_get_gpr(vcpu, rs), 363 2, 0); 364 break; 365 366 default: 367 /* Attempt core-specific emulation below. */ 368 emulated = EMULATE_FAIL; 369 } 370 break; 371 372 case OP_LWZ: 373 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1); 374 break; 375 376 /* TBD: Add support for other 64 bit load variants like ldu, ldux, ldx etc. */ 377 case OP_LD: 378 rt = get_rt(inst); 379 emulated = kvmppc_handle_load(run, vcpu, rt, 8, 1); 380 break; 381 382 case OP_LWZU: 383 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1); 384 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 385 break; 386 387 case OP_LBZ: 388 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1); 389 break; 390 391 case OP_LBZU: 392 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1); 393 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 394 break; 395 396 case OP_STW: 397 emulated = kvmppc_handle_store(run, vcpu, 398 kvmppc_get_gpr(vcpu, rs), 399 4, 1); 400 break; 401 402 /* TBD: Add support for other 64 bit store variants like stdu, stdux, stdx etc. */ 403 case OP_STD: 404 rs = get_rs(inst); 405 emulated = kvmppc_handle_store(run, vcpu, 406 kvmppc_get_gpr(vcpu, rs), 407 8, 1); 408 break; 409 410 case OP_STWU: 411 emulated = kvmppc_handle_store(run, vcpu, 412 kvmppc_get_gpr(vcpu, rs), 413 4, 1); 414 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 415 break; 416 417 case OP_STB: 418 emulated = kvmppc_handle_store(run, vcpu, 419 kvmppc_get_gpr(vcpu, rs), 420 1, 1); 421 break; 422 423 case OP_STBU: 424 emulated = kvmppc_handle_store(run, vcpu, 425 kvmppc_get_gpr(vcpu, rs), 426 1, 1); 427 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 428 break; 429 430 case OP_LHZ: 431 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1); 432 break; 433 434 case OP_LHZU: 435 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1); 436 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 437 break; 438 439 case OP_LHA: 440 emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1); 441 break; 442 443 case OP_LHAU: 444 emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1); 445 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 446 break; 447 448 case OP_STH: 449 emulated = kvmppc_handle_store(run, vcpu, 450 kvmppc_get_gpr(vcpu, rs), 451 2, 1); 452 break; 453 454 case OP_STHU: 455 emulated = kvmppc_handle_store(run, vcpu, 456 kvmppc_get_gpr(vcpu, rs), 457 2, 1); 458 kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed); 459 break; 460 461 default: 462 emulated = EMULATE_FAIL; 463 } 464 465 if (emulated == EMULATE_FAIL) { 466 emulated = vcpu->kvm->arch.kvm_ops->emulate_op(run, vcpu, inst, 467 &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 EXPORT_SYMBOL_GPL(kvmppc_emulate_instruction); 487