1 /* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 1994 - 2000 Ralf Baechle 7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc. 8 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com 9 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved. 10 */ 11 #include <linux/init.h> 12 #include <linux/module.h> 13 #include <linux/signal.h> 14 #include <linux/sched.h> 15 #include <linux/kernel.h> 16 #include <linux/errno.h> 17 #include <linux/string.h> 18 #include <linux/types.h> 19 #include <linux/pagemap.h> 20 #include <linux/ptrace.h> 21 #include <linux/mman.h> 22 #include <linux/mm.h> 23 #include <linux/bootmem.h> 24 #include <linux/highmem.h> 25 #include <linux/swap.h> 26 #include <linux/proc_fs.h> 27 #include <linux/pfn.h> 28 29 #include <asm/bootinfo.h> 30 #include <asm/cachectl.h> 31 #include <asm/cpu.h> 32 #include <asm/dma.h> 33 #include <asm/kmap_types.h> 34 #include <asm/mmu_context.h> 35 #include <asm/sections.h> 36 #include <asm/pgtable.h> 37 #include <asm/pgalloc.h> 38 #include <asm/tlb.h> 39 #include <asm/fixmap.h> 40 41 /* Atomicity and interruptability */ 42 #ifdef CONFIG_MIPS_MT_SMTC 43 44 #include <asm/mipsmtregs.h> 45 46 #define ENTER_CRITICAL(flags) \ 47 { \ 48 unsigned int mvpflags; \ 49 local_irq_save(flags);\ 50 mvpflags = dvpe() 51 #define EXIT_CRITICAL(flags) \ 52 evpe(mvpflags); \ 53 local_irq_restore(flags); \ 54 } 55 #else 56 57 #define ENTER_CRITICAL(flags) local_irq_save(flags) 58 #define EXIT_CRITICAL(flags) local_irq_restore(flags) 59 60 #endif /* CONFIG_MIPS_MT_SMTC */ 61 62 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 63 64 /* 65 * We have up to 8 empty zeroed pages so we can map one of the right colour 66 * when needed. This is necessary only on R4000 / R4400 SC and MC versions 67 * where we have to avoid VCED / VECI exceptions for good performance at 68 * any price. Since page is never written to after the initialization we 69 * don't have to care about aliases on other CPUs. 70 */ 71 unsigned long empty_zero_page, zero_page_mask; 72 73 /* 74 * Not static inline because used by IP27 special magic initialization code 75 */ 76 unsigned long setup_zero_pages(void) 77 { 78 unsigned int order; 79 unsigned long size; 80 struct page *page; 81 82 if (cpu_has_vce) 83 order = 3; 84 else 85 order = 0; 86 87 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 88 if (!empty_zero_page) 89 panic("Oh boy, that early out of memory?"); 90 91 page = virt_to_page((void *)empty_zero_page); 92 split_page(page, order); 93 while (page < virt_to_page((void *)(empty_zero_page + (PAGE_SIZE << order)))) { 94 SetPageReserved(page); 95 page++; 96 } 97 98 size = PAGE_SIZE << order; 99 zero_page_mask = (size - 1) & PAGE_MASK; 100 101 return 1UL << order; 102 } 103 104 /* 105 * These are almost like kmap_atomic / kunmap_atmic except they take an 106 * additional address argument as the hint. 107 */ 108 109 #define kmap_get_fixmap_pte(vaddr) \ 110 pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr)) 111 112 #ifdef CONFIG_MIPS_MT_SMTC 113 static pte_t *kmap_coherent_pte; 114 static void __init kmap_coherent_init(void) 115 { 116 unsigned long vaddr; 117 118 /* cache the first coherent kmap pte */ 119 vaddr = __fix_to_virt(FIX_CMAP_BEGIN); 120 kmap_coherent_pte = kmap_get_fixmap_pte(vaddr); 121 } 122 #else 123 static inline void kmap_coherent_init(void) {} 124 #endif 125 126 void *kmap_coherent(struct page *page, unsigned long addr) 127 { 128 enum fixed_addresses idx; 129 unsigned long vaddr, flags, entrylo; 130 unsigned long old_ctx; 131 pte_t pte; 132 int tlbidx; 133 134 inc_preempt_count(); 135 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); 136 #ifdef CONFIG_MIPS_MT_SMTC 137 idx += FIX_N_COLOURS * smp_processor_id(); 138 #endif 139 vaddr = __fix_to_virt(FIX_CMAP_END - idx); 140 pte = mk_pte(page, PAGE_KERNEL); 141 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32_R1) 142 entrylo = pte.pte_high; 143 #else 144 entrylo = pte_val(pte) >> 6; 145 #endif 146 147 ENTER_CRITICAL(flags); 148 old_ctx = read_c0_entryhi(); 149 write_c0_entryhi(vaddr & (PAGE_MASK << 1)); 150 write_c0_entrylo0(entrylo); 151 write_c0_entrylo1(entrylo); 152 #ifdef CONFIG_MIPS_MT_SMTC 153 set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte); 154 /* preload TLB instead of local_flush_tlb_one() */ 155 mtc0_tlbw_hazard(); 156 tlb_probe(); 157 tlb_probe_hazard(); 158 tlbidx = read_c0_index(); 159 mtc0_tlbw_hazard(); 160 if (tlbidx < 0) 161 tlb_write_random(); 162 else 163 tlb_write_indexed(); 164 #else 165 tlbidx = read_c0_wired(); 166 write_c0_wired(tlbidx + 1); 167 write_c0_index(tlbidx); 168 mtc0_tlbw_hazard(); 169 tlb_write_indexed(); 170 #endif 171 tlbw_use_hazard(); 172 write_c0_entryhi(old_ctx); 173 EXIT_CRITICAL(flags); 174 175 return (void*) vaddr; 176 } 177 178 #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1))) 179 180 void kunmap_coherent(void) 181 { 182 #ifndef CONFIG_MIPS_MT_SMTC 183 unsigned int wired; 184 unsigned long flags, old_ctx; 185 186 ENTER_CRITICAL(flags); 187 old_ctx = read_c0_entryhi(); 188 wired = read_c0_wired() - 1; 189 write_c0_wired(wired); 190 write_c0_index(wired); 191 write_c0_entryhi(UNIQUE_ENTRYHI(wired)); 192 write_c0_entrylo0(0); 193 write_c0_entrylo1(0); 194 mtc0_tlbw_hazard(); 195 tlb_write_indexed(); 196 tlbw_use_hazard(); 197 write_c0_entryhi(old_ctx); 198 EXIT_CRITICAL(flags); 199 #endif 200 dec_preempt_count(); 201 preempt_check_resched(); 202 } 203 204 void copy_user_highpage(struct page *to, struct page *from, 205 unsigned long vaddr, struct vm_area_struct *vma) 206 { 207 void *vfrom, *vto; 208 209 vto = kmap_atomic(to, KM_USER1); 210 if (cpu_has_dc_aliases) { 211 vfrom = kmap_coherent(from, vaddr); 212 copy_page(vto, vfrom); 213 kunmap_coherent(); 214 } else { 215 vfrom = kmap_atomic(from, KM_USER0); 216 copy_page(vto, vfrom); 217 kunmap_atomic(vfrom, KM_USER0); 218 } 219 if (((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) || 220 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) 221 flush_data_cache_page((unsigned long)vto); 222 kunmap_atomic(vto, KM_USER1); 223 /* Make sure this page is cleared on other CPU's too before using it */ 224 smp_wmb(); 225 } 226 227 EXPORT_SYMBOL(copy_user_highpage); 228 229 void copy_to_user_page(struct vm_area_struct *vma, 230 struct page *page, unsigned long vaddr, void *dst, const void *src, 231 unsigned long len) 232 { 233 if (cpu_has_dc_aliases) { 234 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 235 memcpy(vto, src, len); 236 kunmap_coherent(); 237 } else 238 memcpy(dst, src, len); 239 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) 240 flush_cache_page(vma, vaddr, page_to_pfn(page)); 241 } 242 243 EXPORT_SYMBOL(copy_to_user_page); 244 245 void copy_from_user_page(struct vm_area_struct *vma, 246 struct page *page, unsigned long vaddr, void *dst, const void *src, 247 unsigned long len) 248 { 249 if (cpu_has_dc_aliases) { 250 void *vfrom = 251 kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 252 memcpy(dst, vfrom, len); 253 kunmap_coherent(); 254 } else 255 memcpy(dst, src, len); 256 } 257 258 EXPORT_SYMBOL(copy_from_user_page); 259 260 261 #ifdef CONFIG_HIGHMEM 262 unsigned long highstart_pfn, highend_pfn; 263 264 pte_t *kmap_pte; 265 pgprot_t kmap_prot; 266 267 static void __init kmap_init(void) 268 { 269 unsigned long kmap_vstart; 270 271 /* cache the first kmap pte */ 272 kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN); 273 kmap_pte = kmap_get_fixmap_pte(kmap_vstart); 274 275 kmap_prot = PAGE_KERNEL; 276 } 277 #endif /* CONFIG_HIGHMEM */ 278 279 void __init fixrange_init(unsigned long start, unsigned long end, 280 pgd_t *pgd_base) 281 { 282 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC) 283 pgd_t *pgd; 284 pud_t *pud; 285 pmd_t *pmd; 286 pte_t *pte; 287 int i, j, k; 288 unsigned long vaddr; 289 290 vaddr = start; 291 i = __pgd_offset(vaddr); 292 j = __pud_offset(vaddr); 293 k = __pmd_offset(vaddr); 294 pgd = pgd_base + i; 295 296 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { 297 pud = (pud_t *)pgd; 298 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) { 299 pmd = (pmd_t *)pud; 300 for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) { 301 if (pmd_none(*pmd)) { 302 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 303 set_pmd(pmd, __pmd((unsigned long)pte)); 304 if (pte != pte_offset_kernel(pmd, 0)) 305 BUG(); 306 } 307 vaddr += PMD_SIZE; 308 } 309 k = 0; 310 } 311 j = 0; 312 } 313 #endif 314 } 315 316 #ifndef CONFIG_NEED_MULTIPLE_NODES 317 static int __init page_is_ram(unsigned long pagenr) 318 { 319 int i; 320 321 for (i = 0; i < boot_mem_map.nr_map; i++) { 322 unsigned long addr, end; 323 324 if (boot_mem_map.map[i].type != BOOT_MEM_RAM) 325 /* not usable memory */ 326 continue; 327 328 addr = PFN_UP(boot_mem_map.map[i].addr); 329 end = PFN_DOWN(boot_mem_map.map[i].addr + 330 boot_mem_map.map[i].size); 331 332 if (pagenr >= addr && pagenr < end) 333 return 1; 334 } 335 336 return 0; 337 } 338 339 void __init paging_init(void) 340 { 341 unsigned long zones_size[MAX_NR_ZONES] = { 0, }; 342 #ifndef CONFIG_FLATMEM 343 unsigned long zholes_size[MAX_NR_ZONES] = { 0, }; 344 unsigned long i, j, pfn; 345 #endif 346 347 pagetable_init(); 348 349 #ifdef CONFIG_HIGHMEM 350 kmap_init(); 351 #endif 352 kmap_coherent_init(); 353 354 #ifdef CONFIG_ZONE_DMA 355 if (min_low_pfn < MAX_DMA_PFN && MAX_DMA_PFN <= max_low_pfn) { 356 zones_size[ZONE_DMA] = MAX_DMA_PFN - min_low_pfn; 357 zones_size[ZONE_NORMAL] = max_low_pfn - MAX_DMA_PFN; 358 } else if (max_low_pfn < MAX_DMA_PFN) 359 zones_size[ZONE_DMA] = max_low_pfn - min_low_pfn; 360 else 361 #endif 362 zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn; 363 364 #ifdef CONFIG_HIGHMEM 365 zones_size[ZONE_HIGHMEM] = highend_pfn - highstart_pfn; 366 367 if (cpu_has_dc_aliases && zones_size[ZONE_HIGHMEM]) { 368 printk(KERN_WARNING "This processor doesn't support highmem." 369 " %ldk highmem ignored\n", zones_size[ZONE_HIGHMEM]); 370 zones_size[ZONE_HIGHMEM] = 0; 371 } 372 #endif 373 374 #ifdef CONFIG_FLATMEM 375 free_area_init(zones_size); 376 #else 377 pfn = min_low_pfn; 378 for (i = 0; i < MAX_NR_ZONES; i++) 379 for (j = 0; j < zones_size[i]; j++, pfn++) 380 if (!page_is_ram(pfn)) 381 zholes_size[i]++; 382 free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size); 383 #endif 384 } 385 386 static struct kcore_list kcore_mem, kcore_vmalloc; 387 #ifdef CONFIG_64BIT 388 static struct kcore_list kcore_kseg0; 389 #endif 390 391 void __init mem_init(void) 392 { 393 unsigned long codesize, reservedpages, datasize, initsize; 394 unsigned long tmp, ram; 395 396 #ifdef CONFIG_HIGHMEM 397 #ifdef CONFIG_DISCONTIGMEM 398 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 399 #endif 400 max_mapnr = highend_pfn; 401 #else 402 max_mapnr = max_low_pfn; 403 #endif 404 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 405 406 totalram_pages += free_all_bootmem(); 407 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ 408 409 reservedpages = ram = 0; 410 for (tmp = 0; tmp < max_low_pfn; tmp++) 411 if (page_is_ram(tmp)) { 412 ram++; 413 if (PageReserved(pfn_to_page(tmp))) 414 reservedpages++; 415 } 416 num_physpages = ram; 417 418 #ifdef CONFIG_HIGHMEM 419 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 420 struct page *page = mem_map + tmp; 421 422 if (!page_is_ram(tmp)) { 423 SetPageReserved(page); 424 continue; 425 } 426 ClearPageReserved(page); 427 init_page_count(page); 428 __free_page(page); 429 totalhigh_pages++; 430 } 431 totalram_pages += totalhigh_pages; 432 num_physpages += totalhigh_pages; 433 #endif 434 435 codesize = (unsigned long) &_etext - (unsigned long) &_text; 436 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 437 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 438 439 #ifdef CONFIG_64BIT 440 if ((unsigned long) &_text > (unsigned long) CKSEG0) 441 /* The -4 is a hack so that user tools don't have to handle 442 the overflow. */ 443 kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4); 444 #endif 445 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT); 446 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, 447 VMALLOC_END-VMALLOC_START); 448 449 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 450 "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n", 451 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 452 ram << (PAGE_SHIFT-10), 453 codesize >> 10, 454 reservedpages << (PAGE_SHIFT-10), 455 datasize >> 10, 456 initsize >> 10, 457 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))); 458 } 459 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 460 461 void free_init_pages(const char *what, unsigned long begin, unsigned long end) 462 { 463 unsigned long pfn; 464 465 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) { 466 struct page *page = pfn_to_page(pfn); 467 void *addr = phys_to_virt(PFN_PHYS(pfn)); 468 469 ClearPageReserved(page); 470 init_page_count(page); 471 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE); 472 __free_page(page); 473 totalram_pages++; 474 } 475 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 476 } 477 478 #ifdef CONFIG_BLK_DEV_INITRD 479 void free_initrd_mem(unsigned long start, unsigned long end) 480 { 481 free_init_pages("initrd memory", 482 virt_to_phys((void *)start), 483 virt_to_phys((void *)end)); 484 } 485 #endif 486 487 void free_initmem(void) 488 { 489 prom_free_prom_memory(); 490 free_init_pages("unused kernel memory", 491 __pa_symbol(&__init_begin), 492 __pa_symbol(&__init_end)); 493 } 494 495 unsigned long pgd_current[NR_CPUS]; 496 /* 497 * On 64-bit we've got three-level pagetables with a slightly 498 * different layout ... 499 */ 500 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order))) 501 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER); 502 #ifdef CONFIG_64BIT 503 #ifdef MODULE_START 504 pgd_t module_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER); 505 #endif 506 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER); 507 #endif 508 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER); 509