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_SWIOTLB 303 swiotlb_init(0); 304 #endif 305 306 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 307 set_max_mapnr(max_pfn); 308 free_all_bootmem(); 309 310 #ifdef CONFIG_HIGHMEM 311 { 312 unsigned long pfn, highmem_mapnr; 313 314 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 315 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 316 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 317 struct page *page = pfn_to_page(pfn); 318 if (!memblock_is_reserved(paddr)) 319 free_highmem_page(page); 320 } 321 } 322 #endif /* CONFIG_HIGHMEM */ 323 324 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) 325 /* 326 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 327 * functions.... do it here for the non-smp case. 328 */ 329 per_cpu(next_tlbcam_idx, smp_processor_id()) = 330 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 331 #endif 332 333 mem_init_print_info(NULL); 334 #ifdef CONFIG_PPC32 335 pr_info("Kernel virtual memory layout:\n"); 336 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 337 #ifdef CONFIG_HIGHMEM 338 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 339 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 340 #endif /* CONFIG_HIGHMEM */ 341 #ifdef CONFIG_NOT_COHERENT_CACHE 342 pr_info(" * 0x%08lx..0x%08lx : consistent mem\n", 343 IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE); 344 #endif /* CONFIG_NOT_COHERENT_CACHE */ 345 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 346 ioremap_bot, IOREMAP_TOP); 347 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 348 VMALLOC_START, VMALLOC_END); 349 #endif /* CONFIG_PPC32 */ 350 351 mem_init_done = 1; 352 } 353 354 void free_initmem(void) 355 { 356 ppc_md.progress = ppc_printk_progress; 357 free_initmem_default(POISON_FREE_INITMEM); 358 } 359 360 #ifdef CONFIG_BLK_DEV_INITRD 361 void __init free_initrd_mem(unsigned long start, unsigned long end) 362 { 363 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 364 } 365 #endif 366 367 /* 368 * This is called when a page has been modified by the kernel. 369 * It just marks the page as not i-cache clean. We do the i-cache 370 * flush later when the page is given to a user process, if necessary. 371 */ 372 void flush_dcache_page(struct page *page) 373 { 374 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 375 return; 376 /* avoid an atomic op if possible */ 377 if (test_bit(PG_arch_1, &page->flags)) 378 clear_bit(PG_arch_1, &page->flags); 379 } 380 EXPORT_SYMBOL(flush_dcache_page); 381 382 void flush_dcache_icache_page(struct page *page) 383 { 384 #ifdef CONFIG_HUGETLB_PAGE 385 if (PageCompound(page)) { 386 flush_dcache_icache_hugepage(page); 387 return; 388 } 389 #endif 390 #ifdef CONFIG_BOOKE 391 { 392 void *start = kmap_atomic(page); 393 __flush_dcache_icache(start); 394 kunmap_atomic(start); 395 } 396 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64) 397 /* On 8xx there is no need to kmap since highmem is not supported */ 398 __flush_dcache_icache(page_address(page)); 399 #else 400 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); 401 #endif 402 } 403 EXPORT_SYMBOL(flush_dcache_icache_page); 404 405 void clear_user_page(void *page, unsigned long vaddr, struct page *pg) 406 { 407 clear_page(page); 408 409 /* 410 * We shouldn't have to do this, but some versions of glibc 411 * require it (ld.so assumes zero filled pages are icache clean) 412 * - Anton 413 */ 414 flush_dcache_page(pg); 415 } 416 EXPORT_SYMBOL(clear_user_page); 417 418 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, 419 struct page *pg) 420 { 421 copy_page(vto, vfrom); 422 423 /* 424 * We should be able to use the following optimisation, however 425 * there are two problems. 426 * Firstly a bug in some versions of binutils meant PLT sections 427 * were not marked executable. 428 * Secondly the first word in the GOT section is blrl, used 429 * to establish the GOT address. Until recently the GOT was 430 * not marked executable. 431 * - Anton 432 */ 433 #if 0 434 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) 435 return; 436 #endif 437 438 flush_dcache_page(pg); 439 } 440 441 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, 442 unsigned long addr, int len) 443 { 444 unsigned long maddr; 445 446 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); 447 flush_icache_range(maddr, maddr + len); 448 kunmap(page); 449 } 450 EXPORT_SYMBOL(flush_icache_user_range); 451 452 /* 453 * This is called at the end of handling a user page fault, when the 454 * fault has been handled by updating a PTE in the linux page tables. 455 * We use it to preload an HPTE into the hash table corresponding to 456 * the updated linux PTE. 457 * 458 * This must always be called with the pte lock held. 459 */ 460 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 461 pte_t *ptep) 462 { 463 #ifdef CONFIG_PPC_STD_MMU 464 /* 465 * We don't need to worry about _PAGE_PRESENT here because we are 466 * called with either mm->page_table_lock held or ptl lock held 467 */ 468 unsigned long access = 0, trap; 469 470 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 471 if (!pte_young(*ptep) || address >= TASK_SIZE) 472 return; 473 474 /* We try to figure out if we are coming from an instruction 475 * access fault and pass that down to __hash_page so we avoid 476 * double-faulting on execution of fresh text. We have to test 477 * for regs NULL since init will get here first thing at boot 478 * 479 * We also avoid filling the hash if not coming from a fault 480 */ 481 if (current->thread.regs == NULL) 482 return; 483 trap = TRAP(current->thread.regs); 484 if (trap == 0x400) 485 access |= _PAGE_EXEC; 486 else if (trap != 0x300) 487 return; 488 hash_preload(vma->vm_mm, address, access, trap); 489 #endif /* CONFIG_PPC_STD_MMU */ 490 #if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \ 491 && defined(CONFIG_HUGETLB_PAGE) 492 if (is_vm_hugetlb_page(vma)) 493 book3e_hugetlb_preload(vma, address, *ptep); 494 #endif 495 } 496 497 /* 498 * System memory should not be in /proc/iomem but various tools expect it 499 * (eg kdump). 500 */ 501 static int add_system_ram_resources(void) 502 { 503 struct memblock_region *reg; 504 505 for_each_memblock(memory, reg) { 506 struct resource *res; 507 unsigned long base = reg->base; 508 unsigned long size = reg->size; 509 510 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 511 WARN_ON(!res); 512 513 if (res) { 514 res->name = "System RAM"; 515 res->start = base; 516 res->end = base + size - 1; 517 res->flags = IORESOURCE_MEM; 518 WARN_ON(request_resource(&iomem_resource, res) < 0); 519 } 520 } 521 522 return 0; 523 } 524 subsys_initcall(add_system_ram_resources); 525 526 #ifdef CONFIG_STRICT_DEVMEM 527 /* 528 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 529 * is valid. The argument is a physical page number. 530 * 531 * Access has to be given to non-kernel-ram areas as well, these contain the 532 * PCI mmio resources as well as potential bios/acpi data regions. 533 */ 534 int devmem_is_allowed(unsigned long pfn) 535 { 536 if (iomem_is_exclusive(pfn << PAGE_SHIFT)) 537 return 0; 538 if (!page_is_ram(pfn)) 539 return 1; 540 if (page_is_rtas_user_buf(pfn)) 541 return 1; 542 return 0; 543 } 544 #endif /* CONFIG_STRICT_DEVMEM */ 545