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