James Hogan | f5df8e2 | 2012-10-09 10:54:17 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2005,2006,2007,2008,2009,2010 Imagination Technologies |
| 3 | * |
| 4 | */ |
| 5 | |
| 6 | #include <linux/mm.h> |
| 7 | #include <linux/swap.h> |
| 8 | #include <linux/init.h> |
| 9 | #include <linux/bootmem.h> |
| 10 | #include <linux/pagemap.h> |
| 11 | #include <linux/percpu.h> |
| 12 | #include <linux/memblock.h> |
| 13 | #include <linux/initrd.h> |
| 14 | #include <linux/of_fdt.h> |
| 15 | |
| 16 | #include <asm/setup.h> |
| 17 | #include <asm/page.h> |
| 18 | #include <asm/pgalloc.h> |
| 19 | #include <asm/mmu.h> |
| 20 | #include <asm/mmu_context.h> |
| 21 | #include <asm/sections.h> |
| 22 | #include <asm/tlb.h> |
| 23 | #include <asm/user_gateway.h> |
| 24 | #include <asm/mmzone.h> |
| 25 | #include <asm/fixmap.h> |
| 26 | |
| 27 | unsigned long pfn_base; |
| 28 | |
| 29 | pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_data; |
| 30 | |
| 31 | unsigned long empty_zero_page; |
| 32 | |
| 33 | extern char __user_gateway_start; |
| 34 | extern char __user_gateway_end; |
| 35 | |
| 36 | void *gateway_page; |
| 37 | |
| 38 | /* |
| 39 | * Insert the gateway page into a set of page tables, creating the |
| 40 | * page tables if necessary. |
| 41 | */ |
| 42 | static void insert_gateway_page(pgd_t *pgd, unsigned long address) |
| 43 | { |
| 44 | pud_t *pud; |
| 45 | pmd_t *pmd; |
| 46 | pte_t *pte; |
| 47 | |
| 48 | BUG_ON(!pgd_present(*pgd)); |
| 49 | |
| 50 | pud = pud_offset(pgd, address); |
| 51 | BUG_ON(!pud_present(*pud)); |
| 52 | |
| 53 | pmd = pmd_offset(pud, address); |
| 54 | if (!pmd_present(*pmd)) { |
| 55 | pte = alloc_bootmem_pages(PAGE_SIZE); |
| 56 | set_pmd(pmd, __pmd(_PAGE_TABLE | __pa(pte))); |
| 57 | } |
| 58 | |
| 59 | pte = pte_offset_kernel(pmd, address); |
| 60 | set_pte(pte, pfn_pte(__pa(gateway_page) >> PAGE_SHIFT, PAGE_READONLY)); |
| 61 | } |
| 62 | |
| 63 | /* Alloc and map a page in a known location accessible to userspace. */ |
| 64 | static void __init user_gateway_init(void) |
| 65 | { |
| 66 | unsigned long address = USER_GATEWAY_PAGE; |
| 67 | int offset = pgd_index(address); |
| 68 | pgd_t *pgd; |
| 69 | |
| 70 | gateway_page = alloc_bootmem_pages(PAGE_SIZE); |
| 71 | |
| 72 | pgd = swapper_pg_dir + offset; |
| 73 | insert_gateway_page(pgd, address); |
| 74 | |
| 75 | #ifdef CONFIG_METAG_META12 |
| 76 | /* |
| 77 | * Insert the gateway page into our current page tables even |
| 78 | * though we've already inserted it into our reference page |
| 79 | * table (swapper_pg_dir). This is because with a META1 mmu we |
| 80 | * copy just the user address range and not the gateway page |
| 81 | * entry on context switch, see switch_mmu(). |
| 82 | */ |
| 83 | pgd = (pgd_t *)mmu_get_base() + offset; |
| 84 | insert_gateway_page(pgd, address); |
| 85 | #endif /* CONFIG_METAG_META12 */ |
| 86 | |
| 87 | BUG_ON((&__user_gateway_end - &__user_gateway_start) > PAGE_SIZE); |
| 88 | |
| 89 | gateway_page += (address & ~PAGE_MASK); |
| 90 | |
| 91 | memcpy(gateway_page, &__user_gateway_start, |
| 92 | &__user_gateway_end - &__user_gateway_start); |
| 93 | |
| 94 | /* |
| 95 | * We don't need to flush the TLB here, there should be no mapping |
| 96 | * present at boot for this address and only valid mappings are in |
| 97 | * the TLB (apart from on Meta 1.x, but those cached invalid |
| 98 | * mappings should be impossible to hit here). |
| 99 | * |
| 100 | * We don't flush the code cache here even though we have written |
| 101 | * code through the data cache and they may not be coherent. At |
| 102 | * this point we assume there is no stale data in the code cache |
| 103 | * for this address so there is no need to flush. |
| 104 | */ |
| 105 | } |
| 106 | |
| 107 | static void __init allocate_pgdat(unsigned int nid) |
| 108 | { |
| 109 | unsigned long start_pfn, end_pfn; |
| 110 | #ifdef CONFIG_NEED_MULTIPLE_NODES |
| 111 | unsigned long phys; |
| 112 | #endif |
| 113 | |
| 114 | get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); |
| 115 | |
| 116 | #ifdef CONFIG_NEED_MULTIPLE_NODES |
| 117 | phys = __memblock_alloc_base(sizeof(struct pglist_data), |
| 118 | SMP_CACHE_BYTES, end_pfn << PAGE_SHIFT); |
| 119 | /* Retry with all of system memory */ |
| 120 | if (!phys) |
| 121 | phys = __memblock_alloc_base(sizeof(struct pglist_data), |
| 122 | SMP_CACHE_BYTES, |
| 123 | memblock_end_of_DRAM()); |
| 124 | if (!phys) |
| 125 | panic("Can't allocate pgdat for node %d\n", nid); |
| 126 | |
| 127 | NODE_DATA(nid) = __va(phys); |
| 128 | memset(NODE_DATA(nid), 0, sizeof(struct pglist_data)); |
| 129 | |
| 130 | NODE_DATA(nid)->bdata = &bootmem_node_data[nid]; |
| 131 | #endif |
| 132 | |
| 133 | NODE_DATA(nid)->node_start_pfn = start_pfn; |
| 134 | NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn; |
| 135 | } |
| 136 | |
| 137 | static void __init bootmem_init_one_node(unsigned int nid) |
| 138 | { |
| 139 | unsigned long total_pages, paddr; |
| 140 | unsigned long end_pfn; |
| 141 | struct pglist_data *p; |
| 142 | |
| 143 | p = NODE_DATA(nid); |
| 144 | |
| 145 | /* Nothing to do.. */ |
| 146 | if (!p->node_spanned_pages) |
| 147 | return; |
| 148 | |
| 149 | end_pfn = p->node_start_pfn + p->node_spanned_pages; |
| 150 | #ifdef CONFIG_HIGHMEM |
| 151 | if (end_pfn > max_low_pfn) |
| 152 | end_pfn = max_low_pfn; |
| 153 | #endif |
| 154 | |
| 155 | total_pages = bootmem_bootmap_pages(end_pfn - p->node_start_pfn); |
| 156 | |
| 157 | paddr = memblock_alloc(total_pages << PAGE_SHIFT, PAGE_SIZE); |
| 158 | if (!paddr) |
| 159 | panic("Can't allocate bootmap for nid[%d]\n", nid); |
| 160 | |
| 161 | init_bootmem_node(p, paddr >> PAGE_SHIFT, p->node_start_pfn, end_pfn); |
| 162 | |
| 163 | free_bootmem_with_active_regions(nid, end_pfn); |
| 164 | |
| 165 | /* |
| 166 | * XXX Handle initial reservations for the system memory node |
| 167 | * only for the moment, we'll refactor this later for handling |
| 168 | * reservations in other nodes. |
| 169 | */ |
| 170 | if (nid == 0) { |
| 171 | struct memblock_region *reg; |
| 172 | |
| 173 | /* Reserve the sections we're already using. */ |
| 174 | for_each_memblock(reserved, reg) { |
| 175 | unsigned long size = reg->size; |
| 176 | |
| 177 | #ifdef CONFIG_HIGHMEM |
| 178 | /* ...but not highmem */ |
| 179 | if (PFN_DOWN(reg->base) >= highstart_pfn) |
| 180 | continue; |
| 181 | |
| 182 | if (PFN_UP(reg->base + size) > highstart_pfn) |
| 183 | size = (highstart_pfn - PFN_DOWN(reg->base)) |
| 184 | << PAGE_SHIFT; |
| 185 | #endif |
| 186 | |
| 187 | reserve_bootmem(reg->base, size, BOOTMEM_DEFAULT); |
| 188 | } |
| 189 | } |
| 190 | |
| 191 | sparse_memory_present_with_active_regions(nid); |
| 192 | } |
| 193 | |
| 194 | static void __init do_init_bootmem(void) |
| 195 | { |
| 196 | struct memblock_region *reg; |
| 197 | int i; |
| 198 | |
| 199 | /* Add active regions with valid PFNs. */ |
| 200 | for_each_memblock(memory, reg) { |
| 201 | unsigned long start_pfn, end_pfn; |
| 202 | start_pfn = memblock_region_memory_base_pfn(reg); |
| 203 | end_pfn = memblock_region_memory_end_pfn(reg); |
| 204 | memblock_set_node(PFN_PHYS(start_pfn), |
| 205 | PFN_PHYS(end_pfn - start_pfn), 0); |
| 206 | } |
| 207 | |
| 208 | /* All of system RAM sits in node 0 for the non-NUMA case */ |
| 209 | allocate_pgdat(0); |
| 210 | node_set_online(0); |
| 211 | |
| 212 | soc_mem_setup(); |
| 213 | |
| 214 | for_each_online_node(i) |
| 215 | bootmem_init_one_node(i); |
| 216 | |
| 217 | sparse_init(); |
| 218 | } |
| 219 | |
| 220 | extern char _heap_start[]; |
| 221 | |
| 222 | static void __init init_and_reserve_mem(void) |
| 223 | { |
| 224 | unsigned long start_pfn, heap_start; |
| 225 | u64 base = min_low_pfn << PAGE_SHIFT; |
| 226 | u64 size = (max_low_pfn << PAGE_SHIFT) - base; |
| 227 | |
| 228 | heap_start = (unsigned long) &_heap_start; |
| 229 | |
| 230 | memblock_add(base, size); |
| 231 | |
| 232 | /* |
| 233 | * Partially used pages are not usable - thus |
| 234 | * we are rounding upwards: |
| 235 | */ |
| 236 | start_pfn = PFN_UP(__pa(heap_start)); |
| 237 | |
| 238 | /* |
| 239 | * Reserve the kernel text. |
| 240 | */ |
| 241 | memblock_reserve(base, (PFN_PHYS(start_pfn) + PAGE_SIZE - 1) - base); |
| 242 | |
| 243 | #ifdef CONFIG_HIGHMEM |
| 244 | /* |
| 245 | * Add & reserve highmem, so page structures are initialised. |
| 246 | */ |
| 247 | base = highstart_pfn << PAGE_SHIFT; |
| 248 | size = (highend_pfn << PAGE_SHIFT) - base; |
| 249 | if (size) { |
| 250 | memblock_add(base, size); |
| 251 | memblock_reserve(base, size); |
| 252 | } |
| 253 | #endif |
| 254 | } |
| 255 | |
| 256 | #ifdef CONFIG_HIGHMEM |
| 257 | /* |
| 258 | * Ensure we have allocated page tables in swapper_pg_dir for the |
| 259 | * fixed mappings range from 'start' to 'end'. |
| 260 | */ |
| 261 | static void __init allocate_pgtables(unsigned long start, unsigned long end) |
| 262 | { |
| 263 | pgd_t *pgd; |
| 264 | pmd_t *pmd; |
| 265 | pte_t *pte; |
| 266 | int i, j; |
| 267 | unsigned long vaddr; |
| 268 | |
| 269 | vaddr = start; |
| 270 | i = pgd_index(vaddr); |
| 271 | j = pmd_index(vaddr); |
| 272 | pgd = swapper_pg_dir + i; |
| 273 | |
| 274 | for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { |
| 275 | pmd = (pmd_t *)pgd; |
| 276 | for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) { |
| 277 | vaddr += PMD_SIZE; |
| 278 | |
| 279 | if (!pmd_none(*pmd)) |
| 280 | continue; |
| 281 | |
| 282 | pte = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE); |
| 283 | pmd_populate_kernel(&init_mm, pmd, pte); |
| 284 | } |
| 285 | j = 0; |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | static void __init fixedrange_init(void) |
| 290 | { |
| 291 | unsigned long vaddr, end; |
| 292 | pgd_t *pgd; |
| 293 | pud_t *pud; |
| 294 | pmd_t *pmd; |
| 295 | pte_t *pte; |
| 296 | |
| 297 | /* |
| 298 | * Fixed mappings: |
| 299 | */ |
| 300 | vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK; |
| 301 | end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK; |
| 302 | allocate_pgtables(vaddr, end); |
| 303 | |
| 304 | /* |
| 305 | * Permanent kmaps: |
| 306 | */ |
| 307 | vaddr = PKMAP_BASE; |
| 308 | allocate_pgtables(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP); |
| 309 | |
| 310 | pgd = swapper_pg_dir + pgd_index(vaddr); |
| 311 | pud = pud_offset(pgd, vaddr); |
| 312 | pmd = pmd_offset(pud, vaddr); |
| 313 | pte = pte_offset_kernel(pmd, vaddr); |
| 314 | pkmap_page_table = pte; |
| 315 | } |
| 316 | #endif /* CONFIG_HIGHMEM */ |
| 317 | |
| 318 | /* |
| 319 | * paging_init() continues the virtual memory environment setup which |
| 320 | * was begun by the code in arch/metag/kernel/setup.c. |
| 321 | */ |
| 322 | void __init paging_init(unsigned long mem_end) |
| 323 | { |
| 324 | unsigned long max_zone_pfns[MAX_NR_ZONES]; |
| 325 | int nid; |
| 326 | |
| 327 | init_and_reserve_mem(); |
| 328 | |
| 329 | memblock_allow_resize(); |
| 330 | |
| 331 | memblock_dump_all(); |
| 332 | |
| 333 | nodes_clear(node_online_map); |
| 334 | |
| 335 | init_new_context(&init_task, &init_mm); |
| 336 | |
| 337 | memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir)); |
| 338 | |
| 339 | do_init_bootmem(); |
| 340 | mmu_init(mem_end); |
| 341 | |
| 342 | #ifdef CONFIG_HIGHMEM |
| 343 | fixedrange_init(); |
| 344 | kmap_init(); |
| 345 | #endif |
| 346 | |
| 347 | /* Initialize the zero page to a bootmem page, already zeroed. */ |
| 348 | empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE); |
| 349 | |
| 350 | user_gateway_init(); |
| 351 | |
| 352 | memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); |
| 353 | |
| 354 | for_each_online_node(nid) { |
| 355 | pg_data_t *pgdat = NODE_DATA(nid); |
| 356 | unsigned long low, start_pfn; |
| 357 | |
| 358 | start_pfn = pgdat->bdata->node_min_pfn; |
| 359 | low = pgdat->bdata->node_low_pfn; |
| 360 | |
| 361 | if (max_zone_pfns[ZONE_NORMAL] < low) |
| 362 | max_zone_pfns[ZONE_NORMAL] = low; |
| 363 | |
| 364 | #ifdef CONFIG_HIGHMEM |
| 365 | max_zone_pfns[ZONE_HIGHMEM] = highend_pfn; |
| 366 | #endif |
| 367 | pr_info("Node %u: start_pfn = 0x%lx, low = 0x%lx\n", |
| 368 | nid, start_pfn, low); |
| 369 | } |
| 370 | |
| 371 | free_area_init_nodes(max_zone_pfns); |
| 372 | } |
| 373 | |
| 374 | void __init mem_init(void) |
| 375 | { |
| 376 | int nid; |
| 377 | |
| 378 | #ifdef CONFIG_HIGHMEM |
| 379 | unsigned long tmp; |
| 380 | for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { |
| 381 | struct page *page = pfn_to_page(tmp); |
| 382 | ClearPageReserved(page); |
| 383 | init_page_count(page); |
| 384 | __free_page(page); |
| 385 | totalhigh_pages++; |
| 386 | } |
| 387 | totalram_pages += totalhigh_pages; |
| 388 | num_physpages += totalhigh_pages; |
| 389 | #endif /* CONFIG_HIGHMEM */ |
| 390 | |
| 391 | for_each_online_node(nid) { |
| 392 | pg_data_t *pgdat = NODE_DATA(nid); |
| 393 | unsigned long node_pages = 0; |
| 394 | |
| 395 | num_physpages += pgdat->node_present_pages; |
| 396 | |
| 397 | if (pgdat->node_spanned_pages) |
| 398 | node_pages = free_all_bootmem_node(pgdat); |
| 399 | |
| 400 | totalram_pages += node_pages; |
| 401 | } |
| 402 | |
| 403 | pr_info("Memory: %luk/%luk available\n", |
| 404 | (unsigned long)nr_free_pages() << (PAGE_SHIFT - 10), |
| 405 | num_physpages << (PAGE_SHIFT - 10)); |
| 406 | |
| 407 | show_mem(0); |
| 408 | |
| 409 | return; |
| 410 | } |
| 411 | |
| 412 | static void free_init_pages(char *what, unsigned long begin, unsigned long end) |
| 413 | { |
| 414 | unsigned long addr; |
| 415 | |
| 416 | for (addr = begin; addr < end; addr += PAGE_SIZE) { |
| 417 | ClearPageReserved(virt_to_page(addr)); |
| 418 | init_page_count(virt_to_page(addr)); |
| 419 | memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE); |
| 420 | free_page(addr); |
| 421 | totalram_pages++; |
| 422 | } |
| 423 | pr_info("Freeing %s: %luk freed\n", what, (end - begin) >> 10); |
| 424 | } |
| 425 | |
| 426 | void free_initmem(void) |
| 427 | { |
| 428 | free_init_pages("unused kernel memory", |
| 429 | (unsigned long)(&__init_begin), |
| 430 | (unsigned long)(&__init_end)); |
| 431 | } |
| 432 | |
| 433 | #ifdef CONFIG_BLK_DEV_INITRD |
| 434 | void free_initrd_mem(unsigned long start, unsigned long end) |
| 435 | { |
| 436 | end = end & PAGE_MASK; |
| 437 | free_init_pages("initrd memory", start, end); |
| 438 | } |
| 439 | #endif |
| 440 | |
| 441 | #ifdef CONFIG_OF_FLATTREE |
| 442 | void __init early_init_dt_setup_initrd_arch(unsigned long start, |
| 443 | unsigned long end) |
| 444 | { |
| 445 | pr_err("%s(%lx, %lx)\n", |
| 446 | __func__, start, end); |
| 447 | } |
| 448 | #endif /* CONFIG_OF_FLATTREE */ |