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/bug.h> 12 #include <linux/init.h> 13 #include <linux/module.h> 14 #include <linux/signal.h> 15 #include <linux/sched.h> 16 #include <linux/kernel.h> 17 #include <linux/errno.h> 18 #include <linux/string.h> 19 #include <linux/types.h> 20 #include <linux/pagemap.h> 21 #include <linux/ptrace.h> 22 #include <linux/mman.h> 23 #include <linux/mm.h> 24 #include <linux/bootmem.h> 25 #include <linux/highmem.h> 26 #include <linux/swap.h> 27 #include <linux/proc_fs.h> 28 #include <linux/pfn.h> 29 30 #include <asm/asm-offsets.h> 31 #include <asm/bootinfo.h> 32 #include <asm/cachectl.h> 33 #include <asm/cpu.h> 34 #include <asm/dma.h> 35 #include <asm/kmap_types.h> 36 #include <asm/mmu_context.h> 37 #include <asm/sections.h> 38 #include <asm/pgtable.h> 39 #include <asm/pgalloc.h> 40 #include <asm/tlb.h> 41 #include <asm/fixmap.h> 42 43 /* Atomicity and interruptability */ 44 #ifdef CONFIG_MIPS_MT_SMTC 45 46 #include <asm/mipsmtregs.h> 47 48 #define ENTER_CRITICAL(flags) \ 49 { \ 50 unsigned int mvpflags; \ 51 local_irq_save(flags);\ 52 mvpflags = dvpe() 53 #define EXIT_CRITICAL(flags) \ 54 evpe(mvpflags); \ 55 local_irq_restore(flags); \ 56 } 57 #else 58 59 #define ENTER_CRITICAL(flags) local_irq_save(flags) 60 #define EXIT_CRITICAL(flags) local_irq_restore(flags) 61 62 #endif /* CONFIG_MIPS_MT_SMTC */ 63 64 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 65 66 /* 67 * We have up to 8 empty zeroed pages so we can map one of the right colour 68 * when needed. This is necessary only on R4000 / R4400 SC and MC versions 69 * where we have to avoid VCED / VECI exceptions for good performance at 70 * any price. Since page is never written to after the initialization we 71 * don't have to care about aliases on other CPUs. 72 */ 73 unsigned long empty_zero_page, zero_page_mask; 74 75 /* 76 * Not static inline because used by IP27 special magic initialization code 77 */ 78 unsigned long setup_zero_pages(void) 79 { 80 unsigned int order; 81 unsigned long size; 82 struct page *page; 83 84 if (cpu_has_vce) 85 order = 3; 86 else 87 order = 0; 88 89 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 90 if (!empty_zero_page) 91 panic("Oh boy, that early out of memory?"); 92 93 page = virt_to_page((void *)empty_zero_page); 94 split_page(page, order); 95 while (page < virt_to_page((void *)(empty_zero_page + (PAGE_SIZE << order)))) { 96 SetPageReserved(page); 97 page++; 98 } 99 100 size = PAGE_SIZE << order; 101 zero_page_mask = (size - 1) & PAGE_MASK; 102 103 return 1UL << order; 104 } 105 106 /* 107 * These are almost like kmap_atomic / kunmap_atmic except they take an 108 * additional address argument as the hint. 109 */ 110 111 #define kmap_get_fixmap_pte(vaddr) \ 112 pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr)) 113 114 #ifdef CONFIG_MIPS_MT_SMTC 115 static pte_t *kmap_coherent_pte; 116 static void __init kmap_coherent_init(void) 117 { 118 unsigned long vaddr; 119 120 /* cache the first coherent kmap pte */ 121 vaddr = __fix_to_virt(FIX_CMAP_BEGIN); 122 kmap_coherent_pte = kmap_get_fixmap_pte(vaddr); 123 } 124 #else 125 static inline void kmap_coherent_init(void) {} 126 #endif 127 128 void *kmap_coherent(struct page *page, unsigned long addr) 129 { 130 enum fixed_addresses idx; 131 unsigned long vaddr, flags, entrylo; 132 unsigned long old_ctx; 133 pte_t pte; 134 int tlbidx; 135 136 BUG_ON(Page_dcache_dirty(page)); 137 138 inc_preempt_count(); 139 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); 140 #ifdef CONFIG_MIPS_MT_SMTC 141 idx += FIX_N_COLOURS * smp_processor_id(); 142 #endif 143 vaddr = __fix_to_virt(FIX_CMAP_END - idx); 144 pte = mk_pte(page, PAGE_KERNEL); 145 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32_R1) 146 entrylo = pte.pte_high; 147 #else 148 entrylo = pte_val(pte) >> 6; 149 #endif 150 151 ENTER_CRITICAL(flags); 152 old_ctx = read_c0_entryhi(); 153 write_c0_entryhi(vaddr & (PAGE_MASK << 1)); 154 write_c0_entrylo0(entrylo); 155 write_c0_entrylo1(entrylo); 156 #ifdef CONFIG_MIPS_MT_SMTC 157 set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte); 158 /* preload TLB instead of local_flush_tlb_one() */ 159 mtc0_tlbw_hazard(); 160 tlb_probe(); 161 tlb_probe_hazard(); 162 tlbidx = read_c0_index(); 163 mtc0_tlbw_hazard(); 164 if (tlbidx < 0) 165 tlb_write_random(); 166 else 167 tlb_write_indexed(); 168 #else 169 tlbidx = read_c0_wired(); 170 write_c0_wired(tlbidx + 1); 171 write_c0_index(tlbidx); 172 mtc0_tlbw_hazard(); 173 tlb_write_indexed(); 174 #endif 175 tlbw_use_hazard(); 176 write_c0_entryhi(old_ctx); 177 EXIT_CRITICAL(flags); 178 179 return (void*) vaddr; 180 } 181 182 #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1))) 183 184 void kunmap_coherent(void) 185 { 186 #ifndef CONFIG_MIPS_MT_SMTC 187 unsigned int wired; 188 unsigned long flags, old_ctx; 189 190 ENTER_CRITICAL(flags); 191 old_ctx = read_c0_entryhi(); 192 wired = read_c0_wired() - 1; 193 write_c0_wired(wired); 194 write_c0_index(wired); 195 write_c0_entryhi(UNIQUE_ENTRYHI(wired)); 196 write_c0_entrylo0(0); 197 write_c0_entrylo1(0); 198 mtc0_tlbw_hazard(); 199 tlb_write_indexed(); 200 tlbw_use_hazard(); 201 write_c0_entryhi(old_ctx); 202 EXIT_CRITICAL(flags); 203 #endif 204 dec_preempt_count(); 205 preempt_check_resched(); 206 } 207 208 void copy_user_highpage(struct page *to, struct page *from, 209 unsigned long vaddr, struct vm_area_struct *vma) 210 { 211 void *vfrom, *vto; 212 213 vto = kmap_atomic(to, KM_USER1); 214 if (cpu_has_dc_aliases && !Page_dcache_dirty(from)) { 215 vfrom = kmap_coherent(from, vaddr); 216 copy_page(vto, vfrom); 217 kunmap_coherent(); 218 } else { 219 vfrom = kmap_atomic(from, KM_USER0); 220 copy_page(vto, vfrom); 221 kunmap_atomic(vfrom, KM_USER0); 222 } 223 if (((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) || 224 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) 225 flush_data_cache_page((unsigned long)vto); 226 kunmap_atomic(vto, KM_USER1); 227 /* Make sure this page is cleared on other CPU's too before using it */ 228 smp_wmb(); 229 } 230 231 EXPORT_SYMBOL(copy_user_highpage); 232 233 void copy_to_user_page(struct vm_area_struct *vma, 234 struct page *page, unsigned long vaddr, void *dst, const void *src, 235 unsigned long len) 236 { 237 if (cpu_has_dc_aliases) { 238 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 239 memcpy(vto, src, len); 240 kunmap_coherent(); 241 } else 242 memcpy(dst, src, len); 243 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) 244 flush_cache_page(vma, vaddr, page_to_pfn(page)); 245 } 246 247 EXPORT_SYMBOL(copy_to_user_page); 248 249 void copy_from_user_page(struct vm_area_struct *vma, 250 struct page *page, unsigned long vaddr, void *dst, const void *src, 251 unsigned long len) 252 { 253 if (cpu_has_dc_aliases) { 254 void *vfrom = 255 kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 256 memcpy(dst, vfrom, len); 257 kunmap_coherent(); 258 } else 259 memcpy(dst, src, len); 260 } 261 262 EXPORT_SYMBOL(copy_from_user_page); 263 264 265 #ifdef CONFIG_HIGHMEM 266 unsigned long highstart_pfn, highend_pfn; 267 268 pte_t *kmap_pte; 269 pgprot_t kmap_prot; 270 271 static void __init kmap_init(void) 272 { 273 unsigned long kmap_vstart; 274 275 /* cache the first kmap pte */ 276 kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN); 277 kmap_pte = kmap_get_fixmap_pte(kmap_vstart); 278 279 kmap_prot = PAGE_KERNEL; 280 } 281 #endif /* CONFIG_HIGHMEM */ 282 283 void __init fixrange_init(unsigned long start, unsigned long end, 284 pgd_t *pgd_base) 285 { 286 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC) 287 pgd_t *pgd; 288 pud_t *pud; 289 pmd_t *pmd; 290 pte_t *pte; 291 int i, j, k; 292 unsigned long vaddr; 293 294 vaddr = start; 295 i = __pgd_offset(vaddr); 296 j = __pud_offset(vaddr); 297 k = __pmd_offset(vaddr); 298 pgd = pgd_base + i; 299 300 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { 301 pud = (pud_t *)pgd; 302 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) { 303 pmd = (pmd_t *)pud; 304 for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) { 305 if (pmd_none(*pmd)) { 306 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 307 set_pmd(pmd, __pmd((unsigned long)pte)); 308 if (pte != pte_offset_kernel(pmd, 0)) 309 BUG(); 310 } 311 vaddr += PMD_SIZE; 312 } 313 k = 0; 314 } 315 j = 0; 316 } 317 #endif 318 } 319 320 #ifndef CONFIG_NEED_MULTIPLE_NODES 321 static int __init page_is_ram(unsigned long pagenr) 322 { 323 int i; 324 325 for (i = 0; i < boot_mem_map.nr_map; i++) { 326 unsigned long addr, end; 327 328 if (boot_mem_map.map[i].type != BOOT_MEM_RAM) 329 /* not usable memory */ 330 continue; 331 332 addr = PFN_UP(boot_mem_map.map[i].addr); 333 end = PFN_DOWN(boot_mem_map.map[i].addr + 334 boot_mem_map.map[i].size); 335 336 if (pagenr >= addr && pagenr < end) 337 return 1; 338 } 339 340 return 0; 341 } 342 343 void __init paging_init(void) 344 { 345 unsigned long zones_size[MAX_NR_ZONES] = { 0, }; 346 #ifndef CONFIG_FLATMEM 347 unsigned long zholes_size[MAX_NR_ZONES] = { 0, }; 348 unsigned long i, j, pfn; 349 #endif 350 351 pagetable_init(); 352 353 #ifdef CONFIG_HIGHMEM 354 kmap_init(); 355 #endif 356 kmap_coherent_init(); 357 358 #ifdef CONFIG_ZONE_DMA 359 if (min_low_pfn < MAX_DMA_PFN && MAX_DMA_PFN <= max_low_pfn) { 360 zones_size[ZONE_DMA] = MAX_DMA_PFN - min_low_pfn; 361 zones_size[ZONE_NORMAL] = max_low_pfn - MAX_DMA_PFN; 362 } else if (max_low_pfn < MAX_DMA_PFN) 363 zones_size[ZONE_DMA] = max_low_pfn - min_low_pfn; 364 else 365 #endif 366 zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn; 367 368 #ifdef CONFIG_HIGHMEM 369 zones_size[ZONE_HIGHMEM] = highend_pfn - highstart_pfn; 370 371 if (cpu_has_dc_aliases && zones_size[ZONE_HIGHMEM]) { 372 printk(KERN_WARNING "This processor doesn't support highmem." 373 " %ldk highmem ignored\n", zones_size[ZONE_HIGHMEM]); 374 zones_size[ZONE_HIGHMEM] = 0; 375 } 376 #endif 377 378 #ifdef CONFIG_FLATMEM 379 free_area_init(zones_size); 380 #else 381 pfn = min_low_pfn; 382 for (i = 0; i < MAX_NR_ZONES; i++) 383 for (j = 0; j < zones_size[i]; j++, pfn++) 384 if (!page_is_ram(pfn)) 385 zholes_size[i]++; 386 free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size); 387 #endif 388 } 389 390 static struct kcore_list kcore_mem, kcore_vmalloc; 391 #ifdef CONFIG_64BIT 392 static struct kcore_list kcore_kseg0; 393 #endif 394 395 void __init mem_init(void) 396 { 397 unsigned long codesize, reservedpages, datasize, initsize; 398 unsigned long tmp, ram; 399 400 #ifdef CONFIG_HIGHMEM 401 #ifdef CONFIG_DISCONTIGMEM 402 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 403 #endif 404 max_mapnr = highend_pfn; 405 #else 406 max_mapnr = max_low_pfn; 407 #endif 408 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 409 410 totalram_pages += free_all_bootmem(); 411 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ 412 413 reservedpages = ram = 0; 414 for (tmp = 0; tmp < max_low_pfn; tmp++) 415 if (page_is_ram(tmp)) { 416 ram++; 417 if (PageReserved(pfn_to_page(tmp))) 418 reservedpages++; 419 } 420 num_physpages = ram; 421 422 #ifdef CONFIG_HIGHMEM 423 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 424 struct page *page = mem_map + tmp; 425 426 if (!page_is_ram(tmp)) { 427 SetPageReserved(page); 428 continue; 429 } 430 ClearPageReserved(page); 431 init_page_count(page); 432 __free_page(page); 433 totalhigh_pages++; 434 } 435 totalram_pages += totalhigh_pages; 436 num_physpages += totalhigh_pages; 437 #endif 438 439 codesize = (unsigned long) &_etext - (unsigned long) &_text; 440 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 441 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 442 443 #ifdef CONFIG_64BIT 444 if ((unsigned long) &_text > (unsigned long) CKSEG0) 445 /* The -4 is a hack so that user tools don't have to handle 446 the overflow. */ 447 kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4); 448 #endif 449 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT); 450 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, 451 VMALLOC_END-VMALLOC_START); 452 453 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 454 "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n", 455 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 456 ram << (PAGE_SHIFT-10), 457 codesize >> 10, 458 reservedpages << (PAGE_SHIFT-10), 459 datasize >> 10, 460 initsize >> 10, 461 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))); 462 } 463 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 464 465 void free_init_pages(const char *what, unsigned long begin, unsigned long end) 466 { 467 unsigned long pfn; 468 469 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) { 470 struct page *page = pfn_to_page(pfn); 471 void *addr = phys_to_virt(PFN_PHYS(pfn)); 472 473 ClearPageReserved(page); 474 init_page_count(page); 475 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE); 476 __free_page(page); 477 totalram_pages++; 478 } 479 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 480 } 481 482 #ifdef CONFIG_BLK_DEV_INITRD 483 void free_initrd_mem(unsigned long start, unsigned long end) 484 { 485 free_init_pages("initrd memory", 486 virt_to_phys((void *)start), 487 virt_to_phys((void *)end)); 488 } 489 #endif 490 491 void __init_refok free_initmem(void) 492 { 493 prom_free_prom_memory(); 494 free_init_pages("unused kernel memory", 495 __pa_symbol(&__init_begin), 496 __pa_symbol(&__init_end)); 497 } 498 499 unsigned long pgd_current[NR_CPUS]; 500 /* 501 * On 64-bit we've got three-level pagetables with a slightly 502 * different layout ... 503 */ 504 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order))) 505 506 /* 507 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER 508 * are constants. So we use the variants from asm-offset.h until that gcc 509 * will officially be retired. 510 */ 511 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __page_aligned(_PGD_ORDER); 512 #ifdef CONFIG_64BIT 513 #ifdef MODULE_START 514 pgd_t module_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER); 515 #endif 516 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER); 517 #endif 518 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER); 519