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