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 #include <linux/hugetlb.h> 36 37 #include <asm/pgalloc.h> 38 #include <asm/prom.h> 39 #include <asm/io.h> 40 #include <asm/mmu_context.h> 41 #include <asm/pgtable.h> 42 #include <asm/mmu.h> 43 #include <asm/smp.h> 44 #include <asm/machdep.h> 45 #include <asm/btext.h> 46 #include <asm/tlb.h> 47 #include <asm/sections.h> 48 #include <asm/sparsemem.h> 49 #include <asm/vdso.h> 50 #include <asm/fixmap.h> 51 52 #include "mmu_decl.h" 53 54 #ifndef CPU_FTR_COHERENT_ICACHE 55 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */ 56 #define CPU_FTR_NOEXECUTE 0 57 #endif 58 59 int init_bootmem_done; 60 int mem_init_done; 61 phys_addr_t memory_limit; 62 63 #ifdef CONFIG_HIGHMEM 64 pte_t *kmap_pte; 65 pgprot_t kmap_prot; 66 67 EXPORT_SYMBOL(kmap_prot); 68 EXPORT_SYMBOL(kmap_pte); 69 70 static inline pte_t *virt_to_kpte(unsigned long vaddr) 71 { 72 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), 73 vaddr), vaddr), vaddr); 74 } 75 #endif 76 77 int page_is_ram(unsigned long pfn) 78 { 79 #ifndef CONFIG_PPC64 /* XXX for now */ 80 return pfn < max_pfn; 81 #else 82 unsigned long paddr = (pfn << PAGE_SHIFT); 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_noncached(vma_prot); 107 108 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(nid, zone, start_pfn, nr_pages); 137 } 138 #endif /* CONFIG_MEMORY_HOTPLUG */ 139 140 /* 141 * walk_memory_resource() needs to make sure there is no holes in a given 142 * memory range. PPC64 does not maintain the memory layout in /proc/iomem. 143 * Instead it maintains it in lmb.memory structures. Walk through the 144 * memory regions, find holes and callback for contiguous regions. 145 */ 146 int 147 walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, 148 void *arg, int (*func)(unsigned long, unsigned long, void *)) 149 { 150 struct lmb_property res; 151 unsigned long pfn, len; 152 u64 end; 153 int ret = -1; 154 155 res.base = (u64) start_pfn << PAGE_SHIFT; 156 res.size = (u64) nr_pages << PAGE_SHIFT; 157 158 end = res.base + res.size - 1; 159 while ((res.base < end) && (lmb_find(&res) >= 0)) { 160 pfn = (unsigned long)(res.base >> PAGE_SHIFT); 161 len = (unsigned long)(res.size >> PAGE_SHIFT); 162 ret = (*func)(pfn, len, arg); 163 if (ret) 164 break; 165 res.base += (res.size + 1); 166 res.size = (end - res.base + 1); 167 } 168 return ret; 169 } 170 EXPORT_SYMBOL_GPL(walk_system_ram_range); 171 172 /* 173 * Initialize the bootmem system and give it all the memory we 174 * have available. If we are using highmem, we only put the 175 * lowmem into the bootmem system. 176 */ 177 #ifndef CONFIG_NEED_MULTIPLE_NODES 178 void __init do_init_bootmem(void) 179 { 180 unsigned long i; 181 unsigned long start, bootmap_pages; 182 unsigned long total_pages; 183 int boot_mapsize; 184 185 max_low_pfn = max_pfn = lmb_end_of_DRAM() >> PAGE_SHIFT; 186 total_pages = (lmb_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT; 187 #ifdef CONFIG_HIGHMEM 188 total_pages = total_lowmem >> PAGE_SHIFT; 189 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 190 #endif 191 192 /* 193 * Find an area to use for the bootmem bitmap. Calculate the size of 194 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE. 195 * Add 1 additional page in case the address isn't page-aligned. 196 */ 197 bootmap_pages = bootmem_bootmap_pages(total_pages); 198 199 start = lmb_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE); 200 201 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 202 boot_mapsize = init_bootmem_node(NODE_DATA(0), start >> PAGE_SHIFT, min_low_pfn, max_low_pfn); 203 204 /* Add active regions with valid PFNs */ 205 for (i = 0; i < lmb.memory.cnt; i++) { 206 unsigned long start_pfn, end_pfn; 207 start_pfn = lmb.memory.region[i].base >> PAGE_SHIFT; 208 end_pfn = start_pfn + lmb_size_pages(&lmb.memory, i); 209 add_active_range(0, start_pfn, end_pfn); 210 } 211 212 /* Add all physical memory to the bootmem map, mark each area 213 * present. 214 */ 215 #ifdef CONFIG_HIGHMEM 216 free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT); 217 218 /* reserve the sections we're already using */ 219 for (i = 0; i < lmb.reserved.cnt; i++) { 220 unsigned long addr = lmb.reserved.region[i].base + 221 lmb_size_bytes(&lmb.reserved, i) - 1; 222 if (addr < lowmem_end_addr) 223 reserve_bootmem(lmb.reserved.region[i].base, 224 lmb_size_bytes(&lmb.reserved, i), 225 BOOTMEM_DEFAULT); 226 else if (lmb.reserved.region[i].base < lowmem_end_addr) { 227 unsigned long adjusted_size = lowmem_end_addr - 228 lmb.reserved.region[i].base; 229 reserve_bootmem(lmb.reserved.region[i].base, 230 adjusted_size, BOOTMEM_DEFAULT); 231 } 232 } 233 #else 234 free_bootmem_with_active_regions(0, max_pfn); 235 236 /* reserve the sections we're already using */ 237 for (i = 0; i < lmb.reserved.cnt; i++) 238 reserve_bootmem(lmb.reserved.region[i].base, 239 lmb_size_bytes(&lmb.reserved, i), 240 BOOTMEM_DEFAULT); 241 242 #endif 243 /* XXX need to clip this if using highmem? */ 244 sparse_memory_present_with_active_regions(0); 245 246 init_bootmem_done = 1; 247 } 248 249 /* mark pages that don't exist as nosave */ 250 static int __init mark_nonram_nosave(void) 251 { 252 unsigned long lmb_next_region_start_pfn, 253 lmb_region_max_pfn; 254 int i; 255 256 for (i = 0; i < lmb.memory.cnt - 1; i++) { 257 lmb_region_max_pfn = 258 (lmb.memory.region[i].base >> PAGE_SHIFT) + 259 (lmb.memory.region[i].size >> PAGE_SHIFT); 260 lmb_next_region_start_pfn = 261 lmb.memory.region[i+1].base >> PAGE_SHIFT; 262 263 if (lmb_region_max_pfn < lmb_next_region_start_pfn) 264 register_nosave_region(lmb_region_max_pfn, 265 lmb_next_region_start_pfn); 266 } 267 268 return 0; 269 } 270 271 /* 272 * paging_init() sets up the page tables - in fact we've already done this. 273 */ 274 void __init paging_init(void) 275 { 276 unsigned long total_ram = lmb_phys_mem_size(); 277 phys_addr_t top_of_ram = lmb_end_of_DRAM(); 278 unsigned long max_zone_pfns[MAX_NR_ZONES]; 279 280 #ifdef CONFIG_PPC32 281 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1); 282 unsigned long end = __fix_to_virt(FIX_HOLE); 283 284 for (; v < end; v += PAGE_SIZE) 285 map_page(v, 0, 0); /* XXX gross */ 286 #endif 287 288 #ifdef CONFIG_HIGHMEM 289 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 290 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 291 292 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); 293 kmap_prot = PAGE_KERNEL; 294 #endif /* CONFIG_HIGHMEM */ 295 296 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%lx\n", 297 (unsigned long long)top_of_ram, total_ram); 298 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 299 (long int)((top_of_ram - total_ram) >> 20)); 300 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 301 #ifdef CONFIG_HIGHMEM 302 max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT; 303 max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT; 304 #else 305 max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 306 #endif 307 free_area_init_nodes(max_zone_pfns); 308 309 mark_nonram_nosave(); 310 } 311 #endif /* ! CONFIG_NEED_MULTIPLE_NODES */ 312 313 void __init mem_init(void) 314 { 315 #ifdef CONFIG_NEED_MULTIPLE_NODES 316 int nid; 317 #endif 318 pg_data_t *pgdat; 319 unsigned long i; 320 struct page *page; 321 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize; 322 323 num_physpages = lmb.memory.size >> PAGE_SHIFT; 324 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 325 326 #ifdef CONFIG_NEED_MULTIPLE_NODES 327 for_each_online_node(nid) { 328 if (NODE_DATA(nid)->node_spanned_pages != 0) { 329 printk("freeing bootmem node %d\n", nid); 330 totalram_pages += 331 free_all_bootmem_node(NODE_DATA(nid)); 332 } 333 } 334 #else 335 max_mapnr = max_pfn; 336 totalram_pages += free_all_bootmem(); 337 #endif 338 for_each_online_pgdat(pgdat) { 339 for (i = 0; i < pgdat->node_spanned_pages; i++) { 340 if (!pfn_valid(pgdat->node_start_pfn + i)) 341 continue; 342 page = pgdat_page_nr(pgdat, i); 343 if (PageReserved(page)) 344 reservedpages++; 345 } 346 } 347 348 codesize = (unsigned long)&_sdata - (unsigned long)&_stext; 349 datasize = (unsigned long)&_edata - (unsigned long)&_sdata; 350 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin; 351 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start; 352 353 #ifdef CONFIG_HIGHMEM 354 { 355 unsigned long pfn, highmem_mapnr; 356 357 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 358 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 359 struct page *page = pfn_to_page(pfn); 360 if (lmb_is_reserved(pfn << PAGE_SHIFT)) 361 continue; 362 ClearPageReserved(page); 363 init_page_count(page); 364 __free_page(page); 365 totalhigh_pages++; 366 reservedpages--; 367 } 368 totalram_pages += totalhigh_pages; 369 printk(KERN_DEBUG "High memory: %luk\n", 370 totalhigh_pages << (PAGE_SHIFT-10)); 371 } 372 #endif /* CONFIG_HIGHMEM */ 373 374 printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, " 375 "%luk reserved, %luk data, %luk bss, %luk init)\n", 376 nr_free_pages() << (PAGE_SHIFT-10), 377 num_physpages << (PAGE_SHIFT-10), 378 codesize >> 10, 379 reservedpages << (PAGE_SHIFT-10), 380 datasize >> 10, 381 bsssize >> 10, 382 initsize >> 10); 383 384 #ifdef CONFIG_PPC32 385 pr_info("Kernel virtual memory layout:\n"); 386 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 387 #ifdef CONFIG_HIGHMEM 388 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 389 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 390 #endif /* CONFIG_HIGHMEM */ 391 #ifdef CONFIG_NOT_COHERENT_CACHE 392 pr_info(" * 0x%08lx..0x%08lx : consistent mem\n", 393 IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE); 394 #endif /* CONFIG_NOT_COHERENT_CACHE */ 395 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 396 ioremap_bot, IOREMAP_TOP); 397 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 398 VMALLOC_START, VMALLOC_END); 399 #endif /* CONFIG_PPC32 */ 400 401 mem_init_done = 1; 402 } 403 404 /* 405 * This is called when a page has been modified by the kernel. 406 * It just marks the page as not i-cache clean. We do the i-cache 407 * flush later when the page is given to a user process, if necessary. 408 */ 409 void flush_dcache_page(struct page *page) 410 { 411 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 412 return; 413 /* avoid an atomic op if possible */ 414 if (test_bit(PG_arch_1, &page->flags)) 415 clear_bit(PG_arch_1, &page->flags); 416 } 417 EXPORT_SYMBOL(flush_dcache_page); 418 419 void flush_dcache_icache_page(struct page *page) 420 { 421 #ifdef CONFIG_HUGETLB_PAGE 422 if (PageCompound(page)) { 423 flush_dcache_icache_hugepage(page); 424 return; 425 } 426 #endif 427 #ifdef CONFIG_BOOKE 428 { 429 void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE); 430 __flush_dcache_icache(start); 431 kunmap_atomic(start, KM_PPC_SYNC_ICACHE); 432 } 433 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64) 434 /* On 8xx there is no need to kmap since highmem is not supported */ 435 __flush_dcache_icache(page_address(page)); 436 #else 437 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); 438 #endif 439 } 440 441 void clear_user_page(void *page, unsigned long vaddr, struct page *pg) 442 { 443 clear_page(page); 444 445 /* 446 * We shouldnt have to do this, but some versions of glibc 447 * require it (ld.so assumes zero filled pages are icache clean) 448 * - Anton 449 */ 450 flush_dcache_page(pg); 451 } 452 EXPORT_SYMBOL(clear_user_page); 453 454 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, 455 struct page *pg) 456 { 457 copy_page(vto, vfrom); 458 459 /* 460 * We should be able to use the following optimisation, however 461 * there are two problems. 462 * Firstly a bug in some versions of binutils meant PLT sections 463 * were not marked executable. 464 * Secondly the first word in the GOT section is blrl, used 465 * to establish the GOT address. Until recently the GOT was 466 * not marked executable. 467 * - Anton 468 */ 469 #if 0 470 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) 471 return; 472 #endif 473 474 flush_dcache_page(pg); 475 } 476 477 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, 478 unsigned long addr, int len) 479 { 480 unsigned long maddr; 481 482 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); 483 flush_icache_range(maddr, maddr + len); 484 kunmap(page); 485 } 486 EXPORT_SYMBOL(flush_icache_user_range); 487 488 /* 489 * This is called at the end of handling a user page fault, when the 490 * fault has been handled by updating a PTE in the linux page tables. 491 * We use it to preload an HPTE into the hash table corresponding to 492 * the updated linux PTE. 493 * 494 * This must always be called with the pte lock held. 495 */ 496 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 497 pte_t pte) 498 { 499 #ifdef CONFIG_PPC_STD_MMU 500 unsigned long access = 0, trap; 501 502 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 503 if (!pte_young(pte) || address >= TASK_SIZE) 504 return; 505 506 /* We try to figure out if we are coming from an instruction 507 * access fault and pass that down to __hash_page so we avoid 508 * double-faulting on execution of fresh text. We have to test 509 * for regs NULL since init will get here first thing at boot 510 * 511 * We also avoid filling the hash if not coming from a fault 512 */ 513 if (current->thread.regs == NULL) 514 return; 515 trap = TRAP(current->thread.regs); 516 if (trap == 0x400) 517 access |= _PAGE_EXEC; 518 else if (trap != 0x300) 519 return; 520 hash_preload(vma->vm_mm, address, access, trap); 521 #endif /* CONFIG_PPC_STD_MMU */ 522 } 523