1 /* $NetBSD: pmap_bootstrap.c,v 1.2 2002/11/05 07:41:17 chs Exp $ */ 2 3 /* 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Systems Programming Group of the University of Utah Computer 9 * Science Department. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#)pmap_bootstrap.c 8.1 (Berkeley) 6/10/93 40 */ 41 42 #include <sys/param.h> 43 #include <sys/msgbuf.h> 44 #include <sys/proc.h> 45 46 #include <machine/frame.h> 47 #include <machine/cpu.h> 48 #include <machine/vmparam.h> 49 #include <machine/pte.h> 50 51 #include <uvm/uvm_extern.h> 52 53 #define RELOC(v, t) *((t*)((u_int)&(v) + firstpa - KERNBASE)) 54 55 extern char *etext; 56 extern int Sysptsize; 57 extern char *proc0paddr; 58 extern st_entry_t *Sysseg; 59 extern pt_entry_t *Sysptmap, *Sysmap; 60 61 extern int physmem; 62 extern vm_offset_t avail_start, avail_end, virtual_avail, virtual_end; 63 extern int protection_codes[]; 64 65 void pmap_bootstrap __P((vm_offset_t, vm_offset_t)); 66 67 /* 68 * Special purpose kernel virtual addresses, used for mapping 69 * physical pages for a variety of temporary or permanent purposes: 70 * 71 * CADDR1, CADDR2: pmap zero/copy operations 72 * vmmap: /dev/mem, crash dumps, parity error checking 73 * msgbufp: kernel message buffer 74 */ 75 caddr_t CADDR1, CADDR2, vmmap; 76 extern caddr_t msgbufaddr; 77 78 /* 79 * Bootstrap the VM system. 80 * 81 * Called with MMU off so we must relocate all global references by `firstpa' 82 * (don't call any functions here!) `nextpa' is the first available physical 83 * memory address. Returns an updated first PA reflecting the memory we 84 * have allocated. MMU is still off when we return. 85 * 86 * XXX assumes sizeof(u_int) == sizeof(pt_entry_t) 87 * XXX a PIC compiler would make this much easier. 88 */ 89 void 90 pmap_bootstrap(nextpa, firstpa) 91 vm_offset_t nextpa; 92 vm_offset_t firstpa; 93 { 94 vm_offset_t kstpa, kptpa, kptmpa, lkptpa, p0upa; 95 u_int nptpages, kstsize; 96 st_entry_t protoste, *ste; 97 pt_entry_t protopte, *pte, *epte; 98 99 /* 100 * Calculate important physical addresses: 101 * 102 * kstpa kernel segment table 1 page (!040) 103 * N pages (040) 104 * 105 * kptpa statically allocated 106 * kernel PT pages Sysptsize+ pages 107 * 108 * iiopa internal IO space 109 * PT pages IIOMAPSIZE pages 110 * 111 * eiopa external IO space 112 * PT pages EIOMAPSIZE pages 113 * 114 * [ Sysptsize is the number of pages of PT, IIOMAPSIZE and 115 * EIOMAPSIZE are the number of PTEs, hence we need to round 116 * the total to a page boundary with IO maps at the end. ] 117 * 118 * kptmpa kernel PT map 1 page 119 * 120 * lkptpa last kernel PT page 1 page 121 * 122 * p0upa proc 0 u-area UPAGES pages 123 * 124 * The KVA corresponding to any of these PAs is: 125 * (PA - firstpa + KERNBASE). 126 */ 127 if (RELOC(mmutype, int) == MMU_68040) 128 kstsize = MAXKL2SIZE / (NPTEPG/SG4_LEV2SIZE); 129 else 130 kstsize = 1; 131 kstpa = nextpa; 132 nextpa += kstsize * NBPG; 133 kptpa = nextpa; 134 nptpages = RELOC(Sysptsize, int); 135 nextpa += nptpages * NBPG; 136 kptmpa = nextpa; 137 nextpa += NBPG; 138 lkptpa = nextpa; 139 nextpa += NBPG; 140 p0upa = nextpa; 141 nextpa += USPACE; 142 143 /* 144 * Initialize segment table and kernel page table map. 145 * 146 * On 68030s and earlier MMUs the two are identical except for 147 * the valid bits so both are initialized with essentially the 148 * same values. On the 68040, which has a mandatory 3-level 149 * structure, the segment table holds the level 1 table and part 150 * (or all) of the level 2 table and hence is considerably 151 * different. Here the first level consists of 128 descriptors 152 * (512 bytes) each mapping 32mb of address space. Each of these 153 * points to blocks of 128 second level descriptors (512 bytes) 154 * each mapping 256kb. Note that there may be additional "segment 155 * table" pages depending on how large MAXKL2SIZE is. 156 * 157 * Portions of the last segment of KVA space (0xFFF00000 - 158 * 0xFFFFFFFF) are mapped for a couple of purposes. 0xFFF00000 159 * for UPAGES is used for mapping the current process u-area 160 * (u + kernel stack). The very last page (0xFFFFF000) is mapped 161 * to the last physical page of RAM to give us a region in which 162 * PA == VA. We use the first part of this page for enabling 163 * and disabling mapping. The last part of this page also contains 164 * info left by the boot ROM. 165 * 166 * XXX cramming two levels of mapping into the single "segment" 167 * table on the 68040 is intended as a temporary hack to get things 168 * working. The 224mb of address space that this allows will most 169 * likely be insufficient in the future (at least for the kernel). 170 */ 171 if (RELOC(mmutype, int) == MMU_68040) { 172 int num; 173 174 /* 175 * First invalidate the entire "segment table" pages 176 * (levels 1 and 2 have the same "invalid" value). 177 */ 178 pte = (u_int *)kstpa; 179 epte = &pte[kstsize * NPTEPG]; 180 while (pte < epte) 181 *pte++ = SG_NV; 182 183 /* 184 * Initialize level 2 descriptors (which immediately 185 * follow the level 1 table). We need: 186 * NPTEPG / SG4_LEV3SIZE 187 * level 2 descriptors to map each of the nptpages+1 188 * pages of PTEs. Note that we set the "used" bit 189 * now to save the HW the expense of doing it. 190 */ 191 num = (nptpages + 1) * (NPTEPG / SG4_LEV3SIZE); 192 pte = &((u_int *)kstpa)[SG4_LEV1SIZE]; 193 epte = &pte[num]; 194 protoste = kptpa | SG_U | SG_RW | SG_V; 195 while (pte < epte) { 196 *pte++ = protoste; 197 protoste += (SG4_LEV3SIZE * sizeof(st_entry_t)); 198 } 199 200 /* 201 * Initialize level 1 descriptors. We need: 202 * roundup(num, SG4_LEV2SIZE) / SG4_LEV2SIZE 203 * level 1 descriptors to map the `num' level 2's. 204 */ 205 pte = (u_int *)kstpa; 206 epte = &pte[roundup(num, SG4_LEV2SIZE) / SG4_LEV2SIZE]; 207 protoste = (u_int)&pte[SG4_LEV1SIZE] | SG_U | SG_RW | SG_V; 208 while (pte < epte) { 209 *pte++ = protoste; 210 protoste += (SG4_LEV2SIZE * sizeof(st_entry_t)); 211 } 212 213 /* 214 * Initialize the final level 1 descriptor to map the last 215 * block of level 2 descriptors. 216 */ 217 ste = &((u_int *)kstpa)[SG4_LEV1SIZE-1]; 218 pte = &((u_int *)kstpa)[kstsize*NPTEPG - SG4_LEV2SIZE]; 219 *ste = (u_int)pte | SG_U | SG_RW | SG_V; 220 /* 221 * Now initialize the final portion of that block of 222 * descriptors to map the "last PT page". 223 */ 224 pte = &((u_int *)kstpa)[kstsize*NPTEPG - NPTEPG/SG4_LEV3SIZE]; 225 epte = &pte[NPTEPG/SG4_LEV3SIZE]; 226 protoste = lkptpa | SG_U | SG_RW | SG_V; 227 while (pte < epte) { 228 *pte++ = protoste; 229 protoste += (SG4_LEV3SIZE * sizeof(st_entry_t)); 230 } 231 232 /* 233 * Initialize Sysptmap 234 */ 235 pte = (u_int *)kptmpa; 236 epte = &pte[nptpages+1]; 237 protopte = kptpa | PG_RW | PG_CI | PG_V; 238 while (pte < epte) { 239 *pte++ = protopte; 240 protopte += NBPG; 241 } 242 243 /* 244 * Invalidate all but the last remaining entry. 245 */ 246 epte = &((u_int *)kptmpa)[NPTEPG-1]; 247 while (pte < epte) { 248 *pte++ = PG_NV; 249 } 250 /* 251 * Initialize the last to point to the page 252 * table page allocated earlier. 253 */ 254 *pte = lkptpa | PG_RW | PG_CI | PG_V; 255 } else { 256 /* 257 * Map the page table pages in both the HW segment table 258 * and the software Sysptmap. Note that Sysptmap is also 259 * considered a PT page hence the +1. 260 */ 261 ste = (u_int *)kstpa; 262 pte = (u_int *)kptmpa; 263 epte = &pte[nptpages+1]; 264 protoste = kptpa | SG_RW | SG_V; 265 protopte = kptpa | PG_RW | PG_CI | PG_V; 266 while (pte < epte) { 267 *ste++ = protoste; 268 *pte++ = protopte; 269 protoste += NBPG; 270 protopte += NBPG; 271 } 272 /* 273 * Invalidate all but the last remaining entries in both. 274 */ 275 epte = &((u_int *)kptmpa)[NPTEPG-1]; 276 while (pte < epte) { 277 *ste++ = SG_NV; 278 *pte++ = PG_NV; 279 } 280 /* 281 * Initialize the last to point to point to the page 282 * table page allocated earlier. 283 */ 284 *ste = lkptpa | SG_RW | SG_V; 285 *pte = lkptpa | PG_RW | PG_CI | PG_V; 286 } 287 /* 288 * Invalidate all but the final entry in the last kernel PT page 289 * (u-area PTEs will be validated later). The final entry maps 290 * the last page of physical memory. 291 */ 292 pte = (u_int *)lkptpa; 293 epte = &pte[NPTEPG]; 294 while (pte < epte) 295 *pte++ = PG_NV; 296 297 /* 298 * Initialize kernel page table. 299 * Start by invalidating the `nptpages' that we have allocated. 300 */ 301 pte = (u_int *)kptpa; 302 epte = &pte[nptpages * NPTEPG]; 303 while (pte < epte) 304 *pte++ = PG_NV; 305 306 /* 307 * Validate PTEs for kernel text (RO). 308 */ 309 pte = &((u_int *)kptpa)[m68k_btop(KERNBASE)]; 310 epte = &((u_int *)kptpa)[m68k_btop(m68k_trunc_page(&etext))]; 311 protopte = firstpa | PG_RO | PG_V; 312 while (pte < epte) { 313 *pte++ = protopte; 314 protopte += NBPG; 315 } 316 /* 317 * Validate PTEs for kernel data/bss, dynamic data allocated 318 * by us so far (nextpa - firstpa bytes), and pages for proc0 319 * u-area and page table allocated below (RW). 320 */ 321 epte = &((u_int *)kptpa)[m68k_btop(KERNBASE + nextpa - firstpa)]; 322 protopte = (protopte & ~PG_PROT) | PG_RW; 323 /* 324 * Enable copy-back caching of data pages 325 */ 326 if (RELOC(mmutype, int) == MMU_68040) 327 protopte |= PG_CCB; 328 329 while (pte < epte) { 330 *pte++ = protopte; 331 protopte += NBPG; 332 } 333 334 /* 335 * Calculate important exported kernel virtual addresses 336 */ 337 /* 338 * Sysseg: base of kernel segment table 339 */ 340 RELOC(Sysseg, st_entry_t *) = 341 (st_entry_t *)(kstpa - firstpa + KERNBASE); 342 /* 343 * Sysptmap: base of kernel page table map 344 */ 345 RELOC(Sysptmap, pt_entry_t *) = 346 (pt_entry_t *)(kptmpa - firstpa + KERNBASE); 347 /* 348 * Sysmap: kernel page table (as mapped through Sysptmap) 349 * Immediately follows `nptpages' of static kernel page table. 350 */ 351 RELOC(Sysmap, pt_entry_t *) = 352 (pt_entry_t *)m68k_ptob(nptpages * NPTEPG); 353 354 /* 355 * Setup u-area for process 0. 356 */ 357 /* 358 * Zero the u-area. 359 * NOTE: `pte' and `epte' aren't PTEs here. 360 */ 361 pte = (u_int *)p0upa; 362 epte = (u_int *)(p0upa + USPACE); 363 while (pte < epte) 364 *pte++ = 0; 365 /* 366 * Remember the u-area address so it can be loaded in the 367 * proc struct p_addr field later. 368 */ 369 RELOC(proc0paddr, char *) = (char *)(p0upa - firstpa + KERNBASE); 370 371 /* 372 * VM data structures are now initialized, set up data for 373 * the pmap module. 374 * 375 * Note about avail_end: msgbuf is initialized just after 376 * avail_end in machdep.c. Since the last page is used 377 * for rebooting the system (code is copied there and 378 * excution continues from copied code before the MMU 379 * is disabled), the msgbuf will get trounced between 380 * reboots if it's placed in the last physical page. 381 * To work around this, we move avail_end back one more 382 * page so the msgbuf can be preserved. 383 */ 384 RELOC(avail_start, vm_offset_t) = nextpa; 385 RELOC(avail_end, vm_offset_t) = firstpa 386 + m68k_ptob(RELOC(physmem, int)) 387 - m68k_round_page(MSGBUFSIZE) 388 - NBPG; /* if that start of last page??? */ 389 RELOC(virtual_avail, vm_offset_t) = 390 KERNBASE + (nextpa - firstpa); 391 RELOC(virtual_end, vm_offset_t) = VM_MAX_KERNEL_ADDRESS; 392 393 /* 394 * Initialize protection array. 395 * XXX don't use a switch statement, it might produce an 396 * absolute "jmp" table. 397 */ 398 { 399 int *kp; 400 401 kp = &RELOC(protection_codes, int); 402 kp[VM_PROT_NONE|VM_PROT_NONE|VM_PROT_NONE] = 0; 403 kp[VM_PROT_READ|VM_PROT_NONE|VM_PROT_NONE] = PG_RO; 404 kp[VM_PROT_READ|VM_PROT_NONE|VM_PROT_EXECUTE] = PG_RO; 405 kp[VM_PROT_NONE|VM_PROT_NONE|VM_PROT_EXECUTE] = PG_RO; 406 kp[VM_PROT_NONE|VM_PROT_WRITE|VM_PROT_NONE] = PG_RW; 407 kp[VM_PROT_NONE|VM_PROT_WRITE|VM_PROT_EXECUTE] = PG_RW; 408 kp[VM_PROT_READ|VM_PROT_WRITE|VM_PROT_NONE] = PG_RW; 409 kp[VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE] = PG_RW; 410 } 411 412 /* 413 * Kernel page/segment table allocated in locore, 414 * just initialize pointers. 415 */ 416 { 417 struct pmap *kpm = &RELOC(kernel_pmap_store, struct pmap); 418 419 kpm->pm_stab = RELOC(Sysseg, st_entry_t *); 420 kpm->pm_ptab = RELOC(Sysmap, pt_entry_t *); 421 simple_lock_init(&kpm->pm_lock); 422 kpm->pm_count = 1; 423 kpm->pm_stpa = (st_entry_t *)kstpa; 424 /* 425 * For the 040 we also initialize the free level 2 426 * descriptor mask noting that we have used: 427 * 0: level 1 table 428 * 1 to `num': map page tables 429 * MAXKL2SIZE-1: maps last-page page table 430 */ 431 if (RELOC(mmutype, int) == MMU_68040) { 432 int num; 433 434 kpm->pm_stfree = ~l2tobm(0); 435 num = roundup((nptpages + 1) * (NPTEPG / SG4_LEV3SIZE), 436 SG4_LEV2SIZE) / SG4_LEV2SIZE; 437 while (num) 438 kpm->pm_stfree &= ~l2tobm(num--); 439 kpm->pm_stfree &= ~l2tobm(MAXKL2SIZE-1); 440 for (num = MAXKL2SIZE; 441 num < sizeof(kpm->pm_stfree)*NBBY; 442 num++) 443 kpm->pm_stfree &= ~l2tobm(num); 444 } 445 } 446 447 /* 448 * Allocate some fixed, special purpose kernel virtual addresses 449 */ 450 { 451 vm_offset_t va = RELOC(virtual_avail, vm_offset_t); 452 453 RELOC(CADDR1, caddr_t) = (caddr_t)va; 454 va += NBPG; 455 RELOC(CADDR2, caddr_t) = (caddr_t)va; 456 va += NBPG; 457 RELOC(vmmap, caddr_t) = (caddr_t)va; 458 va += NBPG; 459 RELOC(msgbufaddr, caddr_t) = (caddr_t)va; 460 va += m68k_round_page(MSGBUFSIZE); 461 RELOC(virtual_avail, vm_offset_t) = va; 462 } 463 } 464 465 void 466 pmap_init_md(void) 467 { 468 /* Nothing here. */ 469 } 470