1 /* 2 * PowerPC version 3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 4 * 5 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) 6 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 7 * Copyright (C) 1996 Paul Mackerras 8 * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com) 9 * 10 * Derived from "arch/i386/mm/init.c" 11 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 12 * 13 * This program is free software; you can redistribute it and/or 14 * modify it under the terms of the GNU General Public License 15 * as published by the Free Software Foundation; either version 16 * 2 of the License, or (at your option) any later version. 17 * 18 */ 19 20 #include <linux/module.h> 21 #include <linux/sched.h> 22 #include <linux/kernel.h> 23 #include <linux/errno.h> 24 #include <linux/string.h> 25 #include <linux/types.h> 26 #include <linux/mm.h> 27 #include <linux/stddef.h> 28 #include <linux/init.h> 29 #include <linux/bootmem.h> 30 #include <linux/highmem.h> 31 #include <linux/initrd.h> 32 #include <linux/pagemap.h> 33 #include <linux/suspend.h> 34 #include <linux/lmb.h> 35 36 #include <asm/pgalloc.h> 37 #include <asm/prom.h> 38 #include <asm/io.h> 39 #include <asm/mmu_context.h> 40 #include <asm/pgtable.h> 41 #include <asm/mmu.h> 42 #include <asm/smp.h> 43 #include <asm/machdep.h> 44 #include <asm/btext.h> 45 #include <asm/tlb.h> 46 #include <asm/sections.h> 47 #include <asm/sparsemem.h> 48 #include <asm/vdso.h> 49 #include <asm/fixmap.h> 50 51 #include "mmu_decl.h" 52 53 #ifndef CPU_FTR_COHERENT_ICACHE 54 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */ 55 #define CPU_FTR_NOEXECUTE 0 56 #endif 57 58 int init_bootmem_done; 59 int mem_init_done; 60 unsigned long memory_limit; 61 62 #ifdef CONFIG_HIGHMEM 63 pte_t *kmap_pte; 64 pgprot_t kmap_prot; 65 66 EXPORT_SYMBOL(kmap_prot); 67 EXPORT_SYMBOL(kmap_pte); 68 69 static inline pte_t *virt_to_kpte(unsigned long vaddr) 70 { 71 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), 72 vaddr), vaddr), vaddr); 73 } 74 #endif 75 76 int page_is_ram(unsigned long pfn) 77 { 78 unsigned long paddr = (pfn << PAGE_SHIFT); 79 80 #ifndef CONFIG_PPC64 /* XXX for now */ 81 return paddr < __pa(high_memory); 82 #else 83 int i; 84 for (i=0; i < lmb.memory.cnt; i++) { 85 unsigned long base; 86 87 base = lmb.memory.region[i].base; 88 89 if ((paddr >= base) && 90 (paddr < (base + lmb.memory.region[i].size))) { 91 return 1; 92 } 93 } 94 95 return 0; 96 #endif 97 } 98 99 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 100 unsigned long size, pgprot_t vma_prot) 101 { 102 if (ppc_md.phys_mem_access_prot) 103 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 104 105 if (!page_is_ram(pfn)) 106 vma_prot = __pgprot(pgprot_val(vma_prot) 107 | _PAGE_GUARDED | _PAGE_NO_CACHE); 108 return vma_prot; 109 } 110 EXPORT_SYMBOL(phys_mem_access_prot); 111 112 #ifdef CONFIG_MEMORY_HOTPLUG 113 114 #ifdef CONFIG_NUMA 115 int memory_add_physaddr_to_nid(u64 start) 116 { 117 return hot_add_scn_to_nid(start); 118 } 119 #endif 120 121 int arch_add_memory(int nid, u64 start, u64 size) 122 { 123 struct pglist_data *pgdata; 124 struct zone *zone; 125 unsigned long start_pfn = start >> PAGE_SHIFT; 126 unsigned long nr_pages = size >> PAGE_SHIFT; 127 128 pgdata = NODE_DATA(nid); 129 130 start = (unsigned long)__va(start); 131 create_section_mapping(start, start + size); 132 133 /* this should work for most non-highmem platforms */ 134 zone = pgdata->node_zones; 135 136 return __add_pages(zone, start_pfn, nr_pages); 137 } 138 139 #ifdef CONFIG_MEMORY_HOTREMOVE 140 int remove_memory(u64 start, u64 size) 141 { 142 unsigned long start_pfn, end_pfn; 143 int ret; 144 145 start_pfn = start >> PAGE_SHIFT; 146 end_pfn = start_pfn + (size >> PAGE_SHIFT); 147 ret = offline_pages(start_pfn, end_pfn, 120 * HZ); 148 if (ret) 149 goto out; 150 /* Arch-specific calls go here - next patch */ 151 out: 152 return ret; 153 } 154 #endif /* CONFIG_MEMORY_HOTREMOVE */ 155 #endif /* CONFIG_MEMORY_HOTPLUG */ 156 157 /* 158 * walk_memory_resource() needs to make sure there is no holes in a given 159 * memory range. PPC64 does not maintain the memory layout in /proc/iomem. 160 * Instead it maintains it in lmb.memory structures. Walk through the 161 * memory regions, find holes and callback for contiguous regions. 162 */ 163 int 164 walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg, 165 int (*func)(unsigned long, unsigned long, void *)) 166 { 167 struct lmb_property res; 168 unsigned long pfn, len; 169 u64 end; 170 int ret = -1; 171 172 res.base = (u64) start_pfn << PAGE_SHIFT; 173 res.size = (u64) nr_pages << PAGE_SHIFT; 174 175 end = res.base + res.size - 1; 176 while ((res.base < end) && (lmb_find(&res) >= 0)) { 177 pfn = (unsigned long)(res.base >> PAGE_SHIFT); 178 len = (unsigned long)(res.size >> PAGE_SHIFT); 179 ret = (*func)(pfn, len, arg); 180 if (ret) 181 break; 182 res.base += (res.size + 1); 183 res.size = (end - res.base + 1); 184 } 185 return ret; 186 } 187 EXPORT_SYMBOL_GPL(walk_memory_resource); 188 189 void show_mem(void) 190 { 191 unsigned long total = 0, reserved = 0; 192 unsigned long shared = 0, cached = 0; 193 unsigned long highmem = 0; 194 struct page *page; 195 pg_data_t *pgdat; 196 unsigned long i; 197 198 printk("Mem-info:\n"); 199 show_free_areas(); 200 for_each_online_pgdat(pgdat) { 201 unsigned long flags; 202 pgdat_resize_lock(pgdat, &flags); 203 for (i = 0; i < pgdat->node_spanned_pages; i++) { 204 if (!pfn_valid(pgdat->node_start_pfn + i)) 205 continue; 206 page = pgdat_page_nr(pgdat, i); 207 total++; 208 if (PageHighMem(page)) 209 highmem++; 210 if (PageReserved(page)) 211 reserved++; 212 else if (PageSwapCache(page)) 213 cached++; 214 else if (page_count(page)) 215 shared += page_count(page) - 1; 216 } 217 pgdat_resize_unlock(pgdat, &flags); 218 } 219 printk("%ld pages of RAM\n", total); 220 #ifdef CONFIG_HIGHMEM 221 printk("%ld pages of HIGHMEM\n", highmem); 222 #endif 223 printk("%ld reserved pages\n", reserved); 224 printk("%ld pages shared\n", shared); 225 printk("%ld pages swap cached\n", cached); 226 } 227 228 /* 229 * Initialize the bootmem system and give it all the memory we 230 * have available. If we are using highmem, we only put the 231 * lowmem into the bootmem system. 232 */ 233 #ifndef CONFIG_NEED_MULTIPLE_NODES 234 void __init do_init_bootmem(void) 235 { 236 unsigned long i; 237 unsigned long start, bootmap_pages; 238 unsigned long total_pages; 239 int boot_mapsize; 240 241 max_low_pfn = max_pfn = lmb_end_of_DRAM() >> PAGE_SHIFT; 242 total_pages = (lmb_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT; 243 #ifdef CONFIG_HIGHMEM 244 total_pages = total_lowmem >> PAGE_SHIFT; 245 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 246 #endif 247 248 /* 249 * Find an area to use for the bootmem bitmap. Calculate the size of 250 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE. 251 * Add 1 additional page in case the address isn't page-aligned. 252 */ 253 bootmap_pages = bootmem_bootmap_pages(total_pages); 254 255 start = lmb_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE); 256 257 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 258 boot_mapsize = init_bootmem_node(NODE_DATA(0), start >> PAGE_SHIFT, min_low_pfn, max_low_pfn); 259 260 /* Add active regions with valid PFNs */ 261 for (i = 0; i < lmb.memory.cnt; i++) { 262 unsigned long start_pfn, end_pfn; 263 start_pfn = lmb.memory.region[i].base >> PAGE_SHIFT; 264 end_pfn = start_pfn + lmb_size_pages(&lmb.memory, i); 265 add_active_range(0, start_pfn, end_pfn); 266 } 267 268 /* Add all physical memory to the bootmem map, mark each area 269 * present. 270 */ 271 #ifdef CONFIG_HIGHMEM 272 free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT); 273 274 /* reserve the sections we're already using */ 275 for (i = 0; i < lmb.reserved.cnt; i++) { 276 unsigned long addr = lmb.reserved.region[i].base + 277 lmb_size_bytes(&lmb.reserved, i) - 1; 278 if (addr < lowmem_end_addr) 279 reserve_bootmem(lmb.reserved.region[i].base, 280 lmb_size_bytes(&lmb.reserved, i), 281 BOOTMEM_DEFAULT); 282 else if (lmb.reserved.region[i].base < lowmem_end_addr) { 283 unsigned long adjusted_size = lowmem_end_addr - 284 lmb.reserved.region[i].base; 285 reserve_bootmem(lmb.reserved.region[i].base, 286 adjusted_size, BOOTMEM_DEFAULT); 287 } 288 } 289 #else 290 free_bootmem_with_active_regions(0, max_pfn); 291 292 /* reserve the sections we're already using */ 293 for (i = 0; i < lmb.reserved.cnt; i++) 294 reserve_bootmem(lmb.reserved.region[i].base, 295 lmb_size_bytes(&lmb.reserved, i), 296 BOOTMEM_DEFAULT); 297 298 #endif 299 /* XXX need to clip this if using highmem? */ 300 sparse_memory_present_with_active_regions(0); 301 302 init_bootmem_done = 1; 303 } 304 305 /* mark pages that don't exist as nosave */ 306 static int __init mark_nonram_nosave(void) 307 { 308 unsigned long lmb_next_region_start_pfn, 309 lmb_region_max_pfn; 310 int i; 311 312 for (i = 0; i < lmb.memory.cnt - 1; i++) { 313 lmb_region_max_pfn = 314 (lmb.memory.region[i].base >> PAGE_SHIFT) + 315 (lmb.memory.region[i].size >> PAGE_SHIFT); 316 lmb_next_region_start_pfn = 317 lmb.memory.region[i+1].base >> PAGE_SHIFT; 318 319 if (lmb_region_max_pfn < lmb_next_region_start_pfn) 320 register_nosave_region(lmb_region_max_pfn, 321 lmb_next_region_start_pfn); 322 } 323 324 return 0; 325 } 326 327 /* 328 * paging_init() sets up the page tables - in fact we've already done this. 329 */ 330 void __init paging_init(void) 331 { 332 unsigned long total_ram = lmb_phys_mem_size(); 333 phys_addr_t top_of_ram = lmb_end_of_DRAM(); 334 unsigned long max_zone_pfns[MAX_NR_ZONES]; 335 336 #ifdef CONFIG_PPC32 337 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1); 338 unsigned long end = __fix_to_virt(FIX_HOLE); 339 340 for (; v < end; v += PAGE_SIZE) 341 map_page(v, 0, 0); /* XXX gross */ 342 #endif 343 344 #ifdef CONFIG_HIGHMEM 345 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 346 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 347 348 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); 349 kmap_prot = PAGE_KERNEL; 350 #endif /* CONFIG_HIGHMEM */ 351 352 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%lx\n", 353 (u64)top_of_ram, total_ram); 354 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 355 (long int)((top_of_ram - total_ram) >> 20)); 356 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 357 #ifdef CONFIG_HIGHMEM 358 max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT; 359 max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT; 360 #else 361 max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 362 #endif 363 free_area_init_nodes(max_zone_pfns); 364 365 mark_nonram_nosave(); 366 } 367 #endif /* ! CONFIG_NEED_MULTIPLE_NODES */ 368 369 void __init mem_init(void) 370 { 371 #ifdef CONFIG_NEED_MULTIPLE_NODES 372 int nid; 373 #endif 374 pg_data_t *pgdat; 375 unsigned long i; 376 struct page *page; 377 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize; 378 379 num_physpages = lmb.memory.size >> PAGE_SHIFT; 380 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 381 382 #ifdef CONFIG_NEED_MULTIPLE_NODES 383 for_each_online_node(nid) { 384 if (NODE_DATA(nid)->node_spanned_pages != 0) { 385 printk("freeing bootmem node %d\n", nid); 386 totalram_pages += 387 free_all_bootmem_node(NODE_DATA(nid)); 388 } 389 } 390 #else 391 max_mapnr = max_pfn; 392 totalram_pages += free_all_bootmem(); 393 #endif 394 for_each_online_pgdat(pgdat) { 395 for (i = 0; i < pgdat->node_spanned_pages; i++) { 396 if (!pfn_valid(pgdat->node_start_pfn + i)) 397 continue; 398 page = pgdat_page_nr(pgdat, i); 399 if (PageReserved(page)) 400 reservedpages++; 401 } 402 } 403 404 codesize = (unsigned long)&_sdata - (unsigned long)&_stext; 405 datasize = (unsigned long)&_edata - (unsigned long)&_sdata; 406 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin; 407 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start; 408 409 #ifdef CONFIG_HIGHMEM 410 { 411 unsigned long pfn, highmem_mapnr; 412 413 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 414 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 415 struct page *page = pfn_to_page(pfn); 416 if (lmb_is_reserved(pfn << PAGE_SHIFT)) 417 continue; 418 ClearPageReserved(page); 419 init_page_count(page); 420 __free_page(page); 421 totalhigh_pages++; 422 reservedpages--; 423 } 424 totalram_pages += totalhigh_pages; 425 printk(KERN_DEBUG "High memory: %luk\n", 426 totalhigh_pages << (PAGE_SHIFT-10)); 427 } 428 #endif /* CONFIG_HIGHMEM */ 429 430 printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, " 431 "%luk reserved, %luk data, %luk bss, %luk init)\n", 432 (unsigned long)nr_free_pages() << (PAGE_SHIFT-10), 433 num_physpages << (PAGE_SHIFT-10), 434 codesize >> 10, 435 reservedpages << (PAGE_SHIFT-10), 436 datasize >> 10, 437 bsssize >> 10, 438 initsize >> 10); 439 440 mem_init_done = 1; 441 } 442 443 /* 444 * This is called when a page has been modified by the kernel. 445 * It just marks the page as not i-cache clean. We do the i-cache 446 * flush later when the page is given to a user process, if necessary. 447 */ 448 void flush_dcache_page(struct page *page) 449 { 450 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 451 return; 452 /* avoid an atomic op if possible */ 453 if (test_bit(PG_arch_1, &page->flags)) 454 clear_bit(PG_arch_1, &page->flags); 455 } 456 EXPORT_SYMBOL(flush_dcache_page); 457 458 void flush_dcache_icache_page(struct page *page) 459 { 460 #ifdef CONFIG_BOOKE 461 void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE); 462 __flush_dcache_icache(start); 463 kunmap_atomic(start, KM_PPC_SYNC_ICACHE); 464 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64) 465 /* On 8xx there is no need to kmap since highmem is not supported */ 466 __flush_dcache_icache(page_address(page)); 467 #else 468 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); 469 #endif 470 471 } 472 void clear_user_page(void *page, unsigned long vaddr, struct page *pg) 473 { 474 clear_page(page); 475 476 /* 477 * We shouldnt have to do this, but some versions of glibc 478 * require it (ld.so assumes zero filled pages are icache clean) 479 * - Anton 480 */ 481 flush_dcache_page(pg); 482 } 483 EXPORT_SYMBOL(clear_user_page); 484 485 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, 486 struct page *pg) 487 { 488 copy_page(vto, vfrom); 489 490 /* 491 * We should be able to use the following optimisation, however 492 * there are two problems. 493 * Firstly a bug in some versions of binutils meant PLT sections 494 * were not marked executable. 495 * Secondly the first word in the GOT section is blrl, used 496 * to establish the GOT address. Until recently the GOT was 497 * not marked executable. 498 * - Anton 499 */ 500 #if 0 501 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) 502 return; 503 #endif 504 505 flush_dcache_page(pg); 506 } 507 508 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, 509 unsigned long addr, int len) 510 { 511 unsigned long maddr; 512 513 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); 514 flush_icache_range(maddr, maddr + len); 515 kunmap(page); 516 } 517 EXPORT_SYMBOL(flush_icache_user_range); 518 519 /* 520 * This is called at the end of handling a user page fault, when the 521 * fault has been handled by updating a PTE in the linux page tables. 522 * We use it to preload an HPTE into the hash table corresponding to 523 * the updated linux PTE. 524 * 525 * This must always be called with the pte lock held. 526 */ 527 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 528 pte_t pte) 529 { 530 #ifdef CONFIG_PPC_STD_MMU 531 unsigned long access = 0, trap; 532 #endif 533 unsigned long pfn = pte_pfn(pte); 534 535 /* handle i-cache coherency */ 536 if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE) && 537 !cpu_has_feature(CPU_FTR_NOEXECUTE) && 538 pfn_valid(pfn)) { 539 struct page *page = pfn_to_page(pfn); 540 #ifdef CONFIG_8xx 541 /* On 8xx, cache control instructions (particularly 542 * "dcbst" from flush_dcache_icache) fault as write 543 * operation if there is an unpopulated TLB entry 544 * for the address in question. To workaround that, 545 * we invalidate the TLB here, thus avoiding dcbst 546 * misbehaviour. 547 */ 548 _tlbie(address, 0 /* 8xx doesn't care about PID */); 549 #endif 550 /* The _PAGE_USER test should really be _PAGE_EXEC, but 551 * older glibc versions execute some code from no-exec 552 * pages, which for now we are supporting. If exec-only 553 * pages are ever implemented, this will have to change. 554 */ 555 if (!PageReserved(page) && (pte_val(pte) & _PAGE_USER) 556 && !test_bit(PG_arch_1, &page->flags)) { 557 if (vma->vm_mm == current->active_mm) { 558 __flush_dcache_icache((void *) address); 559 } else 560 flush_dcache_icache_page(page); 561 set_bit(PG_arch_1, &page->flags); 562 } 563 } 564 565 #ifdef CONFIG_PPC_STD_MMU 566 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 567 if (!pte_young(pte) || address >= TASK_SIZE) 568 return; 569 570 /* We try to figure out if we are coming from an instruction 571 * access fault and pass that down to __hash_page so we avoid 572 * double-faulting on execution of fresh text. We have to test 573 * for regs NULL since init will get here first thing at boot 574 * 575 * We also avoid filling the hash if not coming from a fault 576 */ 577 if (current->thread.regs == NULL) 578 return; 579 trap = TRAP(current->thread.regs); 580 if (trap == 0x400) 581 access |= _PAGE_EXEC; 582 else if (trap != 0x300) 583 return; 584 hash_preload(vma->vm_mm, address, access, trap); 585 #endif /* CONFIG_PPC_STD_MMU */ 586 } 587