x86_mem.c revision 50477
1/*- 2 * Copyright (c) 1999 Michael Smith <msmith@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/i386/i386/i686_mem.c 50477 1999-08-28 01:08:13Z peter $ 27 */ 28 29#include "opt_smp.h" 30 31#include <sys/param.h> 32#include <sys/kernel.h> 33#include <sys/systm.h> 34#include <sys/ioccom.h> 35#include <sys/malloc.h> 36#include <sys/memrange.h> 37 38#include <machine/md_var.h> 39#include <machine/specialreg.h> 40 41#ifdef SMP 42#include "machine/smp.h" 43#endif 44 45/* 46 * i686 memory range operations 47 * 48 * This code will probably be impenetrable without reference to the 49 * Intel Pentium Pro documentation. 50 */ 51 52static char *mem_owner_bios = "BIOS"; 53 54#define MR686_FIXMTRR (1<<0) 55 56#define mrwithin(mr, a) \ 57 (((a) >= (mr)->mr_base) && ((a) < ((mr)->mr_base + (mr)->mr_len))) 58#define mroverlap(mra, mrb) \ 59 (mrwithin(mra, mrb->mr_base) || mrwithin(mrb, mra->mr_base)) 60 61#define mrvalid(base, len) \ 62 ((!(base & ((1 << 12) - 1))) && /* base is multiple of 4k */ \ 63 ((len) >= (1 << 12)) && /* length is >= 4k */ \ 64 powerof2((len)) && /* ... and power of two */ \ 65 !((base) & ((len) - 1))) /* range is not discontiuous */ 66 67#define mrcopyflags(curr, new) (((curr) & ~MDF_ATTRMASK) | ((new) & MDF_ATTRMASK)) 68 69static void i686_mrinit(struct mem_range_softc *sc); 70static int i686_mrset(struct mem_range_softc *sc, 71 struct mem_range_desc *mrd, 72 int *arg); 73static void i686_mrAPinit(struct mem_range_softc *sc); 74 75static struct mem_range_ops i686_mrops = { 76 i686_mrinit, 77 i686_mrset, 78 i686_mrAPinit 79}; 80 81/* XXX for AP startup hook */ 82static u_int64_t mtrrcap, mtrrdef; 83 84static struct mem_range_desc *mem_range_match(struct mem_range_softc *sc, 85 struct mem_range_desc *mrd); 86static void i686_mrfetch(struct mem_range_softc *sc); 87static int i686_mtrrtype(int flags); 88static void i686_mrstore(struct mem_range_softc *sc); 89static void i686_mrstoreone(void *arg); 90static struct mem_range_desc *i686_mtrrfixsearch(struct mem_range_softc *sc, 91 u_int64_t addr); 92static int i686_mrsetlow(struct mem_range_softc *sc, 93 struct mem_range_desc *mrd, 94 int *arg); 95static int i686_mrsetvariable(struct mem_range_softc *sc, 96 struct mem_range_desc *mrd, 97 int *arg); 98 99/* i686 MTRR type to memory range type conversion */ 100static int i686_mtrrtomrt[] = { 101 MDF_UNCACHEABLE, 102 MDF_WRITECOMBINE, 103 0, 104 0, 105 MDF_WRITETHROUGH, 106 MDF_WRITEPROTECT, 107 MDF_WRITEBACK 108}; 109 110/* 111 * i686 MTRR conflict matrix for overlapping ranges 112 * 113 * Specifically, this matrix allows writeback and uncached ranges 114 * to overlap (the overlapped region is uncached). The array index 115 * is the translated i686 code for the flags (because they map well). 116 */ 117static int i686_mtrrconflict[] = { 118 MDF_WRITECOMBINE | MDF_WRITETHROUGH | MDF_WRITEPROTECT, 119 MDF_ATTRMASK, 120 0, 121 0, 122 MDF_ATTRMASK, 123 MDF_ATTRMASK, 124 MDF_WRITECOMBINE | MDF_WRITETHROUGH | MDF_WRITEPROTECT 125}; 126 127/* 128 * Look for an exactly-matching range. 129 */ 130static struct mem_range_desc * 131mem_range_match(struct mem_range_softc *sc, struct mem_range_desc *mrd) 132{ 133 struct mem_range_desc *cand; 134 int i; 135 136 for (i = 0, cand = sc->mr_desc; i < sc->mr_ndesc; i++, cand++) 137 if ((cand->mr_base == mrd->mr_base) && 138 (cand->mr_len == mrd->mr_len)) 139 return(cand); 140 return(NULL); 141} 142 143/* 144 * Fetch the current mtrr settings from the current CPU (assumed to all 145 * be in sync in the SMP case). Note that if we are here, we assume 146 * that MTRRs are enabled, and we may or may not have fixed MTRRs. 147 */ 148static void 149i686_mrfetch(struct mem_range_softc *sc) 150{ 151 struct mem_range_desc *mrd; 152 u_int64_t msrv; 153 int i, j, msr; 154 155 mrd = sc->mr_desc; 156 157 /* Get fixed-range MTRRs */ 158 if (sc->mr_cap & MR686_FIXMTRR) { 159 msr = MSR_MTRR64kBase; 160 for (i = 0; i < (MTRR_N64K / 8); i++, msr++) { 161 msrv = rdmsr(msr); 162 for (j = 0; j < 8; j++, mrd++) { 163 mrd->mr_flags = (mrd->mr_flags & ~MDF_ATTRMASK) | 164 i686_mtrrtomrt[msrv & 0xff] | 165 MDF_ACTIVE; 166 if (mrd->mr_owner[0] == 0) 167 strcpy(mrd->mr_owner, mem_owner_bios); 168 msrv = msrv >> 8; 169 } 170 } 171 msr = MSR_MTRR16kBase; 172 for (i = 0; i < (MTRR_N16K / 8); i++, msr++) { 173 msrv = rdmsr(msr); 174 for (j = 0; j < 8; j++, mrd++) { 175 mrd->mr_flags = (mrd->mr_flags & ~MDF_ATTRMASK) | 176 i686_mtrrtomrt[msrv & 0xff] | 177 MDF_ACTIVE; 178 if (mrd->mr_owner[0] == 0) 179 strcpy(mrd->mr_owner, mem_owner_bios); 180 msrv = msrv >> 8; 181 } 182 } 183 msr = MSR_MTRR4kBase; 184 for (i = 0; i < (MTRR_N4K / 8); i++, msr++) { 185 msrv = rdmsr(msr); 186 for (j = 0; j < 8; j++, mrd++) { 187 mrd->mr_flags = (mrd->mr_flags & ~MDF_ATTRMASK) | 188 i686_mtrrtomrt[msrv & 0xff] | 189 MDF_ACTIVE; 190 if (mrd->mr_owner[0] == 0) 191 strcpy(mrd->mr_owner, mem_owner_bios); 192 msrv = msrv >> 8; 193 } 194 } 195 } 196 197 /* Get remainder which must be variable MTRRs */ 198 msr = MSR_MTRRVarBase; 199 for (; (mrd - sc->mr_desc) < sc->mr_ndesc; msr += 2, mrd++) { 200 msrv = rdmsr(msr); 201 mrd->mr_flags = (mrd->mr_flags & ~MDF_ATTRMASK) | 202 i686_mtrrtomrt[msrv & 0xff]; 203 mrd->mr_base = msrv & 0x0000000ffffff000LL; 204 msrv = rdmsr(msr + 1); 205 mrd->mr_flags = (msrv & 0x800) ? 206 (mrd->mr_flags | MDF_ACTIVE) : 207 (mrd->mr_flags & ~MDF_ACTIVE); 208 /* Compute the range from the mask. Ick. */ 209 mrd->mr_len = (~(msrv & 0x0000000ffffff000LL) & 0x0000000fffffffffLL) + 1; 210 if (!mrvalid(mrd->mr_base, mrd->mr_len)) 211 mrd->mr_flags |= MDF_BOGUS; 212 /* If unclaimed and active, must be the BIOS */ 213 if ((mrd->mr_flags & MDF_ACTIVE) && (mrd->mr_owner[0] == 0)) 214 strcpy(mrd->mr_owner, mem_owner_bios); 215 } 216} 217 218/* 219 * Return the MTRR memory type matching a region's flags 220 */ 221static int 222i686_mtrrtype(int flags) 223{ 224 int i; 225 226 flags &= MDF_ATTRMASK; 227 228 for (i = 0; i < (sizeof(i686_mtrrtomrt) / sizeof(i686_mtrrtomrt[0])); i++) { 229 if (i686_mtrrtomrt[i] == 0) 230 continue; 231 if (flags == i686_mtrrtomrt[i]) 232 return(i); 233 } 234 return(-1); 235} 236 237/* 238 * Update running CPU(s) MTRRs to match the ranges in the descriptor 239 * list. 240 * 241 * XXX Must be called with interrupts enabled. 242 */ 243static void 244i686_mrstore(struct mem_range_softc *sc) 245{ 246#ifdef SMP 247 /* 248 * We should use all_but_self_ipi() to call other CPUs into a 249 * locking gate, then call a target function to do this work. 250 * The "proper" solution involves a generalised locking gate 251 * implementation, not ready yet. 252 */ 253 smp_rendezvous(NULL, i686_mrstoreone, NULL, (void *)sc); 254#else 255 disable_intr(); /* disable interrupts */ 256 i686_mrstoreone((void *)sc); 257 enable_intr(); 258#endif 259} 260 261/* 262 * Update the current CPU's MTRRs with those represented in the 263 * descriptor list. Note that we do this wholesale rather than 264 * just stuffing one entry; this is simpler (but slower, of course). 265 */ 266static void 267i686_mrstoreone(void *arg) 268{ 269 struct mem_range_softc *sc = (struct mem_range_softc *)arg; 270 struct mem_range_desc *mrd; 271 u_int64_t msrv; 272 int i, j, msr; 273 u_int cr4save; 274 275 mrd = sc->mr_desc; 276 277 cr4save = rcr4(); /* save cr4 */ 278 if (cr4save & CR4_PGE) 279 load_cr4(cr4save & ~CR4_PGE); 280 load_cr0((rcr0() & ~CR0_NW) | CR0_CD); /* disable caches (CD = 1, NW = 0) */ 281 wbinvd(); /* flush caches, TLBs */ 282 wrmsr(MSR_MTRRdefType, rdmsr(MSR_MTRRdefType) & ~0x800); /* disable MTRRs (E = 0) */ 283 284 /* Set fixed-range MTRRs */ 285 if (sc->mr_cap & MR686_FIXMTRR) { 286 msr = MSR_MTRR64kBase; 287 for (i = 0; i < (MTRR_N64K / 8); i++, msr++) { 288 msrv = 0; 289 for (j = 7; j >= 0; j--) { 290 msrv = msrv << 8; 291 msrv |= (i686_mtrrtype((mrd + j)->mr_flags) & 0xff); 292 } 293 wrmsr(msr, msrv); 294 mrd += 8; 295 } 296 msr = MSR_MTRR16kBase; 297 for (i = 0; i < (MTRR_N16K / 8); i++, msr++) { 298 msrv = 0; 299 for (j = 7; j >= 0; j--) { 300 msrv = msrv << 8; 301 msrv |= (i686_mtrrtype((mrd + j)->mr_flags) & 0xff); 302 } 303 wrmsr(msr, msrv); 304 mrd += 8; 305 } 306 msr = MSR_MTRR4kBase; 307 for (i = 0; i < (MTRR_N4K / 8); i++, msr++) { 308 msrv = 0; 309 for (j = 7; j >= 0; j--) { 310 msrv = msrv << 8; 311 msrv |= (i686_mtrrtype((mrd + j)->mr_flags) & 0xff); 312 } 313 wrmsr(msr, msrv); 314 mrd += 8; 315 } 316 } 317 318 /* Set remainder which must be variable MTRRs */ 319 msr = MSR_MTRRVarBase; 320 for (; (mrd - sc->mr_desc) < sc->mr_ndesc; msr += 2, mrd++) { 321 /* base/type register */ 322 if (mrd->mr_flags & MDF_ACTIVE) { 323 msrv = mrd->mr_base & 0x0000000ffffff000LL; 324 msrv |= (i686_mtrrtype(mrd->mr_flags) & 0xff); 325 } else { 326 msrv = 0; 327 } 328 wrmsr(msr, msrv); 329 330 /* mask/active register */ 331 if (mrd->mr_flags & MDF_ACTIVE) { 332 msrv = 0x800 | (~(mrd->mr_len - 1) & 0x0000000ffffff000LL); 333 } else { 334 msrv = 0; 335 } 336 wrmsr(msr + 1, msrv); 337 } 338 wbinvd(); /* flush caches, TLBs */ 339 wrmsr(MSR_MTRRdefType, rdmsr(MSR_MTRRdefType) | 0x800); /* restore MTRR state */ 340 load_cr0(rcr0() & ~(CR0_CD | CR0_NW)); /* enable caches CD = 0 and NW = 0 */ 341 load_cr4(cr4save); /* restore cr4 */ 342} 343 344/* 345 * Hunt for the fixed MTRR referencing (addr) 346 */ 347static struct mem_range_desc * 348i686_mtrrfixsearch(struct mem_range_softc *sc, u_int64_t addr) 349{ 350 struct mem_range_desc *mrd; 351 int i; 352 353 for (i = 0, mrd = sc->mr_desc; i < (MTRR_N64K + MTRR_N16K + MTRR_N4K); i++, mrd++) 354 if ((addr >= mrd->mr_base) && (addr < (mrd->mr_base + mrd->mr_len))) 355 return(mrd); 356 return(NULL); 357} 358 359/* 360 * Try to satisfy the given range request by manipulating the fixed MTRRs that 361 * cover low memory. 362 * 363 * Note that we try to be generous here; we'll bloat the range out to the 364 * next higher/lower boundary to avoid the consumer having to know too much 365 * about the mechanisms here. 366 * 367 * XXX note that this will have to be updated when we start supporting "busy" ranges. 368 */ 369static int 370i686_mrsetlow(struct mem_range_softc *sc, struct mem_range_desc *mrd, int *arg) 371{ 372 struct mem_range_desc *first_md, *last_md, *curr_md; 373 374 /* range check */ 375 if (((first_md = i686_mtrrfixsearch(sc, mrd->mr_base)) == NULL) || 376 ((last_md = i686_mtrrfixsearch(sc, mrd->mr_base + mrd->mr_len - 1)) == NULL)) 377 return(EINVAL); 378 379 /* set flags, clear set-by-firmware flag */ 380 for (curr_md = first_md; curr_md <= last_md; curr_md++) { 381 curr_md->mr_flags = mrcopyflags(curr_md->mr_flags & ~MDF_FIRMWARE, mrd->mr_flags); 382 bcopy(mrd->mr_owner, curr_md->mr_owner, sizeof(mrd->mr_owner)); 383 } 384 385 return(0); 386} 387 388 389/* 390 * Modify/add a variable MTRR to satisfy the request. 391 * 392 * XXX needs to be updated to properly support "busy" ranges. 393 */ 394static int 395i686_mrsetvariable(struct mem_range_softc *sc, struct mem_range_desc *mrd, int *arg) 396{ 397 struct mem_range_desc *curr_md, *free_md; 398 int i; 399 400 /* 401 * Scan the currently active variable descriptors, look for 402 * one we exactly match (straight takeover) and for possible 403 * accidental overlaps. 404 * Keep track of the first empty variable descriptor in case we 405 * can't perform a takeover. 406 */ 407 i = (sc->mr_cap & MR686_FIXMTRR) ? MTRR_N64K + MTRR_N16K + MTRR_N4K : 0; 408 curr_md = sc->mr_desc + i; 409 free_md = NULL; 410 for (; i < sc->mr_ndesc; i++, curr_md++) { 411 if (curr_md->mr_flags & MDF_ACTIVE) { 412 /* exact match? */ 413 if ((curr_md->mr_base == mrd->mr_base) && 414 (curr_md->mr_len == mrd->mr_len)) { 415 /* whoops, owned by someone */ 416 if (curr_md->mr_flags & MDF_BUSY) 417 return(EBUSY); 418 /* Ok, just hijack this entry */ 419 free_md = curr_md; 420 break; 421 } 422 /* non-exact overlap ? */ 423 if (mroverlap(curr_md, mrd)) { 424 /* between conflicting region types? */ 425 if ((i686_mtrrconflict[i686_mtrrtype(curr_md->mr_flags)] & mrd->mr_flags) || 426 (i686_mtrrconflict[i686_mtrrtype(mrd->mr_flags)] & curr_md->mr_flags)) 427 return(EINVAL); 428 } 429 } else if (free_md == NULL) { 430 free_md = curr_md; 431 } 432 } 433 /* got somewhere to put it? */ 434 if (free_md == NULL) 435 return(ENOSPC); 436 437 /* Set up new descriptor */ 438 free_md->mr_base = mrd->mr_base; 439 free_md->mr_len = mrd->mr_len; 440 free_md->mr_flags = mrcopyflags(MDF_ACTIVE, mrd->mr_flags); 441 bcopy(mrd->mr_owner, free_md->mr_owner, sizeof(mrd->mr_owner)); 442 return(0); 443} 444 445/* 446 * Handle requests to set memory range attributes by manipulating MTRRs. 447 * 448 */ 449static int 450i686_mrset(struct mem_range_softc *sc, struct mem_range_desc *mrd, int *arg) 451{ 452 struct mem_range_desc *targ; 453 int error = 0; 454 455 switch(*arg) { 456 case MEMRANGE_SET_UPDATE: 457 /* make sure that what's being asked for is even possible at all */ 458 if (!mrvalid(mrd->mr_base, mrd->mr_len) || 459 (i686_mtrrtype(mrd->mr_flags & MDF_ATTRMASK) == -1)) 460 return(EINVAL); 461 462#define FIXTOP ((MTRR_N64K * 0x10000) + (MTRR_N16K * 0x4000) + (MTRR_N4K * 0x1000)) 463 464 /* are the "low memory" conditions applicable? */ 465 if ((sc->mr_cap & MR686_FIXMTRR) && 466 ((mrd->mr_base + mrd->mr_len) <= FIXTOP)) { 467 if ((error = i686_mrsetlow(sc, mrd, arg)) != 0) 468 return(error); 469 } else { 470 /* it's time to play with variable MTRRs */ 471 if ((error = i686_mrsetvariable(sc, mrd, arg)) != 0) 472 return(error); 473 } 474 break; 475 476 case MEMRANGE_SET_REMOVE: 477 if ((targ = mem_range_match(sc, mrd)) == NULL) 478 return(ENOENT); 479 if (targ->mr_flags & MDF_FIXACTIVE) 480 return(EPERM); 481 if (targ->mr_flags & MDF_BUSY) 482 return(EBUSY); 483 targ->mr_flags &= ~MDF_ACTIVE; 484 targ->mr_owner[0] = 0; 485 break; 486 487 default: 488 return(EOPNOTSUPP); 489 } 490 491 /* update the hardware */ 492 i686_mrstore(sc); 493 i686_mrfetch(sc); /* refetch to see where we're at */ 494 return(0); 495} 496 497/* 498 * Work out how many ranges we support, initialise storage for them, 499 * fetch the initial settings. 500 */ 501static void 502i686_mrinit(struct mem_range_softc *sc) 503{ 504 struct mem_range_desc *mrd; 505 int nmdesc = 0; 506 int i; 507 508 mtrrcap = rdmsr(MSR_MTRRcap); 509 mtrrdef = rdmsr(MSR_MTRRdefType); 510 511 /* For now, bail out if MTRRs are not enabled */ 512 if (!(mtrrdef & 0x800)) { 513 if (bootverbose) 514 printf("CPU supports MTRRs but not enabled\n"); 515 return; 516 } 517 nmdesc = mtrrcap & 0xff; 518 printf("Pentium Pro MTRR support enabled\n"); 519 520 /* If fixed MTRRs supported and enabled */ 521 if ((mtrrcap & 0x100) && (mtrrdef & 0x400)) { 522 sc->mr_cap = MR686_FIXMTRR; 523 nmdesc += MTRR_N64K + MTRR_N16K + MTRR_N4K; 524 } 525 526 sc->mr_desc = 527 (struct mem_range_desc *)malloc(nmdesc * sizeof(struct mem_range_desc), 528 M_MEMDESC, M_WAITOK); 529 bzero(sc->mr_desc, nmdesc * sizeof(struct mem_range_desc)); 530 sc->mr_ndesc = nmdesc; 531 532 mrd = sc->mr_desc; 533 534 /* Populate the fixed MTRR entries' base/length */ 535 if (sc->mr_cap & MR686_FIXMTRR) { 536 for (i = 0; i < MTRR_N64K; i++, mrd++) { 537 mrd->mr_base = i * 0x10000; 538 mrd->mr_len = 0x10000; 539 mrd->mr_flags = MDF_FIXBASE | MDF_FIXLEN | MDF_FIXACTIVE; 540 } 541 for (i = 0; i < MTRR_N16K; i++, mrd++) { 542 mrd->mr_base = i * 0x4000 + 0x80000; 543 mrd->mr_len = 0x4000; 544 mrd->mr_flags = MDF_FIXBASE | MDF_FIXLEN | MDF_FIXACTIVE; 545 } 546 for (i = 0; i < MTRR_N4K; i++, mrd++) { 547 mrd->mr_base = i * 0x1000 + 0xc0000; 548 mrd->mr_len = 0x1000; 549 mrd->mr_flags = MDF_FIXBASE | MDF_FIXLEN | MDF_FIXACTIVE; 550 } 551 } 552 553 /* 554 * Get current settings, anything set now is considered to have 555 * been set by the firmware. (XXX has something already played here?) 556 */ 557 i686_mrfetch(sc); 558 mrd = sc->mr_desc; 559 for (i = 0; i < sc->mr_ndesc; i++, mrd++) { 560 if (mrd->mr_flags & MDF_ACTIVE) 561 mrd->mr_flags |= MDF_FIRMWARE; 562 } 563} 564 565/* 566 * Initialise MTRRs on an AP after the BSP has run the init code. 567 */ 568static void 569i686_mrAPinit(struct mem_range_softc *sc) 570{ 571 i686_mrstoreone((void *)sc); /* set MTRRs to match BSP */ 572 wrmsr(MSR_MTRRdefType, mtrrdef); /* set MTRR behaviour to match BSP */ 573} 574 575static void 576i686_mem_drvinit(void *unused) 577{ 578 /* Try for i686 MTRRs */ 579 if (!strcmp(cpu_vendor, "GenuineIntel") && 580 cpu_feature & CPUID_MTRR && 581 (cpu_id & 0xf00) == 0x600) { 582 mem_range_softc.mr_op = &i686_mrops; 583 } 584} 585 586SYSINIT(i686memdev,SI_SUB_DRIVERS,SI_ORDER_FIRST,i686_mem_drvinit,NULL) 587 588 589