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