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/export.h> 21 #include <linux/sched.h> 22 #include <linux/kernel.h> 23 #include <linux/errno.h> 24 #include <linux/string.h> 25 #include <linux/gfp.h> 26 #include <linux/types.h> 27 #include <linux/mm.h> 28 #include <linux/stddef.h> 29 #include <linux/init.h> 30 #include <linux/bootmem.h> 31 #include <linux/highmem.h> 32 #include <linux/initrd.h> 33 #include <linux/pagemap.h> 34 #include <linux/suspend.h> 35 #include <linux/memblock.h> 36 #include <linux/hugetlb.h> 37 #include <linux/slab.h> 38 39 #include <asm/pgalloc.h> 40 #include <asm/prom.h> 41 #include <asm/io.h> 42 #include <asm/mmu_context.h> 43 #include <asm/pgtable.h> 44 #include <asm/mmu.h> 45 #include <asm/smp.h> 46 #include <asm/machdep.h> 47 #include <asm/btext.h> 48 #include <asm/tlb.h> 49 #include <asm/sections.h> 50 #include <asm/sparsemem.h> 51 #include <asm/vdso.h> 52 #include <asm/fixmap.h> 53 #include <asm/swiotlb.h> 54 #include <asm/rtas.h> 55 56 #include "mmu_decl.h" 57 58 #ifndef CPU_FTR_COHERENT_ICACHE 59 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */ 60 #define CPU_FTR_NOEXECUTE 0 61 #endif 62 63 int init_bootmem_done; 64 int mem_init_done; 65 phys_addr_t memory_limit; 66 67 #ifdef CONFIG_HIGHMEM 68 pte_t *kmap_pte; 69 pgprot_t kmap_prot; 70 71 EXPORT_SYMBOL(kmap_prot); 72 EXPORT_SYMBOL(kmap_pte); 73 74 static inline pte_t *virt_to_kpte(unsigned long vaddr) 75 { 76 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), 77 vaddr), vaddr), vaddr); 78 } 79 #endif 80 81 int page_is_ram(unsigned long pfn) 82 { 83 #ifndef CONFIG_PPC64 /* XXX for now */ 84 return pfn < max_pfn; 85 #else 86 unsigned long paddr = (pfn << PAGE_SHIFT); 87 struct memblock_region *reg; 88 89 for_each_memblock(memory, reg) 90 if (paddr >= reg->base && paddr < (reg->base + reg->size)) 91 return 1; 92 return 0; 93 #endif 94 } 95 96 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 97 unsigned long size, pgprot_t vma_prot) 98 { 99 if (ppc_md.phys_mem_access_prot) 100 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 101 102 if (!page_is_ram(pfn)) 103 vma_prot = pgprot_noncached(vma_prot); 104 105 return vma_prot; 106 } 107 EXPORT_SYMBOL(phys_mem_access_prot); 108 109 #ifdef CONFIG_MEMORY_HOTPLUG 110 111 #ifdef CONFIG_NUMA 112 int memory_add_physaddr_to_nid(u64 start) 113 { 114 return hot_add_scn_to_nid(start); 115 } 116 #endif 117 118 int arch_add_memory(int nid, u64 start, u64 size) 119 { 120 struct pglist_data *pgdata; 121 struct zone *zone; 122 unsigned long start_pfn = start >> PAGE_SHIFT; 123 unsigned long nr_pages = size >> PAGE_SHIFT; 124 125 pgdata = NODE_DATA(nid); 126 127 start = (unsigned long)__va(start); 128 if (create_section_mapping(start, start + size)) 129 return -EINVAL; 130 131 /* this should work for most non-highmem platforms */ 132 zone = pgdata->node_zones; 133 134 return __add_pages(nid, zone, start_pfn, nr_pages); 135 } 136 #endif /* CONFIG_MEMORY_HOTPLUG */ 137 138 /* 139 * walk_memory_resource() needs to make sure there is no holes in a given 140 * memory range. PPC64 does not maintain the memory layout in /proc/iomem. 141 * Instead it maintains it in memblock.memory structures. Walk through the 142 * memory regions, find holes and callback for contiguous regions. 143 */ 144 int 145 walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, 146 void *arg, int (*func)(unsigned long, unsigned long, void *)) 147 { 148 struct memblock_region *reg; 149 unsigned long end_pfn = start_pfn + nr_pages; 150 unsigned long tstart, tend; 151 int ret = -1; 152 153 for_each_memblock(memory, reg) { 154 tstart = max(start_pfn, memblock_region_memory_base_pfn(reg)); 155 tend = min(end_pfn, memblock_region_memory_end_pfn(reg)); 156 if (tstart >= tend) 157 continue; 158 ret = (*func)(tstart, tend - tstart, arg); 159 if (ret) 160 break; 161 } 162 return ret; 163 } 164 EXPORT_SYMBOL_GPL(walk_system_ram_range); 165 166 /* 167 * Initialize the bootmem system and give it all the memory we 168 * have available. If we are using highmem, we only put the 169 * lowmem into the bootmem system. 170 */ 171 #ifndef CONFIG_NEED_MULTIPLE_NODES 172 void __init do_init_bootmem(void) 173 { 174 unsigned long start, bootmap_pages; 175 unsigned long total_pages; 176 struct memblock_region *reg; 177 int boot_mapsize; 178 179 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 180 total_pages = (memblock_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT; 181 #ifdef CONFIG_HIGHMEM 182 total_pages = total_lowmem >> PAGE_SHIFT; 183 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 184 #endif 185 186 /* 187 * Find an area to use for the bootmem bitmap. Calculate the size of 188 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE. 189 * Add 1 additional page in case the address isn't page-aligned. 190 */ 191 bootmap_pages = bootmem_bootmap_pages(total_pages); 192 193 start = memblock_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE); 194 195 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 196 boot_mapsize = init_bootmem_node(NODE_DATA(0), start >> PAGE_SHIFT, min_low_pfn, max_low_pfn); 197 198 /* Add active regions with valid PFNs */ 199 for_each_memblock(memory, reg) { 200 unsigned long start_pfn, end_pfn; 201 start_pfn = memblock_region_memory_base_pfn(reg); 202 end_pfn = memblock_region_memory_end_pfn(reg); 203 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, 0); 204 } 205 206 /* Add all physical memory to the bootmem map, mark each area 207 * present. 208 */ 209 #ifdef CONFIG_HIGHMEM 210 free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT); 211 212 /* reserve the sections we're already using */ 213 for_each_memblock(reserved, reg) { 214 unsigned long top = reg->base + reg->size - 1; 215 if (top < lowmem_end_addr) 216 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT); 217 else if (reg->base < lowmem_end_addr) { 218 unsigned long trunc_size = lowmem_end_addr - reg->base; 219 reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT); 220 } 221 } 222 #else 223 free_bootmem_with_active_regions(0, max_pfn); 224 225 /* reserve the sections we're already using */ 226 for_each_memblock(reserved, reg) 227 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT); 228 #endif 229 /* XXX need to clip this if using highmem? */ 230 sparse_memory_present_with_active_regions(0); 231 232 init_bootmem_done = 1; 233 } 234 235 /* mark pages that don't exist as nosave */ 236 static int __init mark_nonram_nosave(void) 237 { 238 struct memblock_region *reg, *prev = NULL; 239 240 for_each_memblock(memory, reg) { 241 if (prev && 242 memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg)) 243 register_nosave_region(memblock_region_memory_end_pfn(prev), 244 memblock_region_memory_base_pfn(reg)); 245 prev = reg; 246 } 247 return 0; 248 } 249 250 /* 251 * paging_init() sets up the page tables - in fact we've already done this. 252 */ 253 void __init paging_init(void) 254 { 255 unsigned long long total_ram = memblock_phys_mem_size(); 256 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 257 unsigned long max_zone_pfns[MAX_NR_ZONES]; 258 259 #ifdef CONFIG_PPC32 260 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1); 261 unsigned long end = __fix_to_virt(FIX_HOLE); 262 263 for (; v < end; v += PAGE_SIZE) 264 map_page(v, 0, 0); /* XXX gross */ 265 #endif 266 267 #ifdef CONFIG_HIGHMEM 268 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 269 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 270 271 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); 272 kmap_prot = PAGE_KERNEL; 273 #endif /* CONFIG_HIGHMEM */ 274 275 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 276 (unsigned long long)top_of_ram, total_ram); 277 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 278 (long int)((top_of_ram - total_ram) >> 20)); 279 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 280 #ifdef CONFIG_HIGHMEM 281 max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT; 282 max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT; 283 #else 284 max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 285 #endif 286 free_area_init_nodes(max_zone_pfns); 287 288 mark_nonram_nosave(); 289 } 290 #endif /* ! CONFIG_NEED_MULTIPLE_NODES */ 291 292 void __init mem_init(void) 293 { 294 #ifdef CONFIG_NEED_MULTIPLE_NODES 295 int nid; 296 #endif 297 pg_data_t *pgdat; 298 unsigned long i; 299 struct page *page; 300 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize; 301 302 #ifdef CONFIG_SWIOTLB 303 if (ppc_swiotlb_enable) 304 swiotlb_init(1); 305 #endif 306 307 num_physpages = memblock_phys_mem_size() >> PAGE_SHIFT; 308 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 309 310 #ifdef CONFIG_NEED_MULTIPLE_NODES 311 for_each_online_node(nid) { 312 if (NODE_DATA(nid)->node_spanned_pages != 0) { 313 printk("freeing bootmem node %d\n", nid); 314 totalram_pages += 315 free_all_bootmem_node(NODE_DATA(nid)); 316 } 317 } 318 #else 319 max_mapnr = max_pfn; 320 totalram_pages += free_all_bootmem(); 321 #endif 322 for_each_online_pgdat(pgdat) { 323 for (i = 0; i < pgdat->node_spanned_pages; i++) { 324 if (!pfn_valid(pgdat->node_start_pfn + i)) 325 continue; 326 page = pgdat_page_nr(pgdat, i); 327 if (PageReserved(page)) 328 reservedpages++; 329 } 330 } 331 332 codesize = (unsigned long)&_sdata - (unsigned long)&_stext; 333 datasize = (unsigned long)&_edata - (unsigned long)&_sdata; 334 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin; 335 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start; 336 337 #ifdef CONFIG_HIGHMEM 338 { 339 unsigned long pfn, highmem_mapnr; 340 341 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 342 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 343 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 344 struct page *page = pfn_to_page(pfn); 345 if (memblock_is_reserved(paddr)) 346 continue; 347 ClearPageReserved(page); 348 init_page_count(page); 349 __free_page(page); 350 totalhigh_pages++; 351 reservedpages--; 352 } 353 totalram_pages += totalhigh_pages; 354 printk(KERN_DEBUG "High memory: %luk\n", 355 totalhigh_pages << (PAGE_SHIFT-10)); 356 } 357 #endif /* CONFIG_HIGHMEM */ 358 359 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) 360 /* 361 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 362 * functions.... do it here for the non-smp case. 363 */ 364 per_cpu(next_tlbcam_idx, smp_processor_id()) = 365 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 366 #endif 367 368 printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, " 369 "%luk reserved, %luk data, %luk bss, %luk init)\n", 370 nr_free_pages() << (PAGE_SHIFT-10), 371 num_physpages << (PAGE_SHIFT-10), 372 codesize >> 10, 373 reservedpages << (PAGE_SHIFT-10), 374 datasize >> 10, 375 bsssize >> 10, 376 initsize >> 10); 377 378 #ifdef CONFIG_PPC32 379 pr_info("Kernel virtual memory layout:\n"); 380 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 381 #ifdef CONFIG_HIGHMEM 382 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 383 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 384 #endif /* CONFIG_HIGHMEM */ 385 #ifdef CONFIG_NOT_COHERENT_CACHE 386 pr_info(" * 0x%08lx..0x%08lx : consistent mem\n", 387 IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE); 388 #endif /* CONFIG_NOT_COHERENT_CACHE */ 389 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 390 ioremap_bot, IOREMAP_TOP); 391 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 392 VMALLOC_START, VMALLOC_END); 393 #endif /* CONFIG_PPC32 */ 394 395 mem_init_done = 1; 396 } 397 398 void free_initmem(void) 399 { 400 unsigned long addr; 401 402 ppc_md.progress = ppc_printk_progress; 403 404 addr = (unsigned long)__init_begin; 405 for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) { 406 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE); 407 ClearPageReserved(virt_to_page(addr)); 408 init_page_count(virt_to_page(addr)); 409 free_page(addr); 410 totalram_pages++; 411 } 412 pr_info("Freeing unused kernel memory: %luk freed\n", 413 ((unsigned long)__init_end - 414 (unsigned long)__init_begin) >> 10); 415 } 416 417 #ifdef CONFIG_BLK_DEV_INITRD 418 void __init free_initrd_mem(unsigned long start, unsigned long end) 419 { 420 if (start >= end) 421 return; 422 423 start = _ALIGN_DOWN(start, PAGE_SIZE); 424 end = _ALIGN_UP(end, PAGE_SIZE); 425 pr_info("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); 426 427 for (; start < end; start += PAGE_SIZE) { 428 ClearPageReserved(virt_to_page(start)); 429 init_page_count(virt_to_page(start)); 430 free_page(start); 431 totalram_pages++; 432 } 433 } 434 #endif 435 436 /* 437 * This is called when a page has been modified by the kernel. 438 * It just marks the page as not i-cache clean. We do the i-cache 439 * flush later when the page is given to a user process, if necessary. 440 */ 441 void flush_dcache_page(struct page *page) 442 { 443 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 444 return; 445 /* avoid an atomic op if possible */ 446 if (test_bit(PG_arch_1, &page->flags)) 447 clear_bit(PG_arch_1, &page->flags); 448 } 449 EXPORT_SYMBOL(flush_dcache_page); 450 451 void flush_dcache_icache_page(struct page *page) 452 { 453 #ifdef CONFIG_HUGETLB_PAGE 454 if (PageCompound(page)) { 455 flush_dcache_icache_hugepage(page); 456 return; 457 } 458 #endif 459 #ifdef CONFIG_BOOKE 460 { 461 void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE); 462 __flush_dcache_icache(start); 463 kunmap_atomic(start, KM_PPC_SYNC_ICACHE); 464 } 465 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64) 466 /* On 8xx there is no need to kmap since highmem is not supported */ 467 __flush_dcache_icache(page_address(page)); 468 #else 469 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); 470 #endif 471 } 472 473 void clear_user_page(void *page, unsigned long vaddr, struct page *pg) 474 { 475 clear_page(page); 476 477 /* 478 * We shouldn't have to do this, but some versions of glibc 479 * require it (ld.so assumes zero filled pages are icache clean) 480 * - Anton 481 */ 482 flush_dcache_page(pg); 483 } 484 EXPORT_SYMBOL(clear_user_page); 485 486 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, 487 struct page *pg) 488 { 489 copy_page(vto, vfrom); 490 491 /* 492 * We should be able to use the following optimisation, however 493 * there are two problems. 494 * Firstly a bug in some versions of binutils meant PLT sections 495 * were not marked executable. 496 * Secondly the first word in the GOT section is blrl, used 497 * to establish the GOT address. Until recently the GOT was 498 * not marked executable. 499 * - Anton 500 */ 501 #if 0 502 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) 503 return; 504 #endif 505 506 flush_dcache_page(pg); 507 } 508 509 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, 510 unsigned long addr, int len) 511 { 512 unsigned long maddr; 513 514 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); 515 flush_icache_range(maddr, maddr + len); 516 kunmap(page); 517 } 518 EXPORT_SYMBOL(flush_icache_user_range); 519 520 /* 521 * This is called at the end of handling a user page fault, when the 522 * fault has been handled by updating a PTE in the linux page tables. 523 * We use it to preload an HPTE into the hash table corresponding to 524 * the updated linux PTE. 525 * 526 * This must always be called with the pte lock held. 527 */ 528 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 529 pte_t *ptep) 530 { 531 #ifdef CONFIG_PPC_STD_MMU 532 unsigned long access = 0, trap; 533 534 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 535 if (!pte_young(*ptep) || address >= TASK_SIZE) 536 return; 537 538 /* We try to figure out if we are coming from an instruction 539 * access fault and pass that down to __hash_page so we avoid 540 * double-faulting on execution of fresh text. We have to test 541 * for regs NULL since init will get here first thing at boot 542 * 543 * We also avoid filling the hash if not coming from a fault 544 */ 545 if (current->thread.regs == NULL) 546 return; 547 trap = TRAP(current->thread.regs); 548 if (trap == 0x400) 549 access |= _PAGE_EXEC; 550 else if (trap != 0x300) 551 return; 552 hash_preload(vma->vm_mm, address, access, trap); 553 #endif /* CONFIG_PPC_STD_MMU */ 554 #if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \ 555 && defined(CONFIG_HUGETLB_PAGE) 556 if (is_vm_hugetlb_page(vma)) 557 book3e_hugetlb_preload(vma, address, *ptep); 558 #endif 559 } 560 561 /* 562 * System memory should not be in /proc/iomem but various tools expect it 563 * (eg kdump). 564 */ 565 static int add_system_ram_resources(void) 566 { 567 struct memblock_region *reg; 568 569 for_each_memblock(memory, reg) { 570 struct resource *res; 571 unsigned long base = reg->base; 572 unsigned long size = reg->size; 573 574 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 575 WARN_ON(!res); 576 577 if (res) { 578 res->name = "System RAM"; 579 res->start = base; 580 res->end = base + size - 1; 581 res->flags = IORESOURCE_MEM; 582 WARN_ON(request_resource(&iomem_resource, res) < 0); 583 } 584 } 585 586 return 0; 587 } 588 subsys_initcall(add_system_ram_resources); 589 590 #ifdef CONFIG_STRICT_DEVMEM 591 /* 592 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 593 * is valid. The argument is a physical page number. 594 * 595 * Access has to be given to non-kernel-ram areas as well, these contain the 596 * PCI mmio resources as well as potential bios/acpi data regions. 597 */ 598 int devmem_is_allowed(unsigned long pfn) 599 { 600 if (iomem_is_exclusive(pfn << PAGE_SHIFT)) 601 return 0; 602 if (!page_is_ram(pfn)) 603 return 1; 604 if (page_is_rtas_user_buf(pfn)) 605 return 1; 606 return 0; 607 } 608 #endif /* CONFIG_STRICT_DEVMEM */ 609