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_mapped(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 && page_mapped(page)) { 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 (cpu_has_dc_aliases) 244 SetPageDcacheDirty(page); 245 } 246 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) 247 flush_cache_page(vma, vaddr, page_to_pfn(page)); 248 } 249 250 EXPORT_SYMBOL(copy_to_user_page); 251 252 void copy_from_user_page(struct vm_area_struct *vma, 253 struct page *page, unsigned long vaddr, void *dst, const void *src, 254 unsigned long len) 255 { 256 if (cpu_has_dc_aliases && page_mapped(page)) { 257 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 258 memcpy(dst, vfrom, len); 259 kunmap_coherent(); 260 } else { 261 memcpy(dst, src, len); 262 if (cpu_has_dc_aliases) 263 SetPageDcacheDirty(page); 264 } 265 } 266 267 EXPORT_SYMBOL(copy_from_user_page); 268 269 270 #ifdef CONFIG_HIGHMEM 271 unsigned long highstart_pfn, highend_pfn; 272 273 pte_t *kmap_pte; 274 pgprot_t kmap_prot; 275 276 static void __init kmap_init(void) 277 { 278 unsigned long kmap_vstart; 279 280 /* cache the first kmap pte */ 281 kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN); 282 kmap_pte = kmap_get_fixmap_pte(kmap_vstart); 283 284 kmap_prot = PAGE_KERNEL; 285 } 286 #endif /* CONFIG_HIGHMEM */ 287 288 void __init fixrange_init(unsigned long start, unsigned long end, 289 pgd_t *pgd_base) 290 { 291 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC) 292 pgd_t *pgd; 293 pud_t *pud; 294 pmd_t *pmd; 295 pte_t *pte; 296 int i, j, k; 297 unsigned long vaddr; 298 299 vaddr = start; 300 i = __pgd_offset(vaddr); 301 j = __pud_offset(vaddr); 302 k = __pmd_offset(vaddr); 303 pgd = pgd_base + i; 304 305 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { 306 pud = (pud_t *)pgd; 307 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) { 308 pmd = (pmd_t *)pud; 309 for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) { 310 if (pmd_none(*pmd)) { 311 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 312 set_pmd(pmd, __pmd((unsigned long)pte)); 313 if (pte != pte_offset_kernel(pmd, 0)) 314 BUG(); 315 } 316 vaddr += PMD_SIZE; 317 } 318 k = 0; 319 } 320 j = 0; 321 } 322 #endif 323 } 324 325 #ifndef CONFIG_NEED_MULTIPLE_NODES 326 static int __init page_is_ram(unsigned long pagenr) 327 { 328 int i; 329 330 for (i = 0; i < boot_mem_map.nr_map; i++) { 331 unsigned long addr, end; 332 333 if (boot_mem_map.map[i].type != BOOT_MEM_RAM) 334 /* not usable memory */ 335 continue; 336 337 addr = PFN_UP(boot_mem_map.map[i].addr); 338 end = PFN_DOWN(boot_mem_map.map[i].addr + 339 boot_mem_map.map[i].size); 340 341 if (pagenr >= addr && pagenr < end) 342 return 1; 343 } 344 345 return 0; 346 } 347 348 void __init paging_init(void) 349 { 350 unsigned long max_zone_pfns[MAX_NR_ZONES]; 351 unsigned long lastpfn; 352 353 pagetable_init(); 354 355 #ifdef CONFIG_HIGHMEM 356 kmap_init(); 357 #endif 358 kmap_coherent_init(); 359 360 #ifdef CONFIG_ZONE_DMA 361 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 362 #endif 363 #ifdef CONFIG_ZONE_DMA32 364 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 365 #endif 366 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 367 lastpfn = max_low_pfn; 368 #ifdef CONFIG_HIGHMEM 369 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn; 370 lastpfn = highend_pfn; 371 372 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) { 373 printk(KERN_WARNING "This processor doesn't support highmem." 374 " %ldk highmem ignored\n", 375 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10)); 376 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn; 377 lastpfn = max_low_pfn; 378 } 379 #endif 380 381 free_area_init_nodes(max_zone_pfns); 382 } 383 384 static struct kcore_list kcore_mem, kcore_vmalloc; 385 #ifdef CONFIG_64BIT 386 static struct kcore_list kcore_kseg0; 387 #endif 388 389 void __init mem_init(void) 390 { 391 unsigned long codesize, reservedpages, datasize, initsize; 392 unsigned long tmp, ram; 393 394 #ifdef CONFIG_HIGHMEM 395 #ifdef CONFIG_DISCONTIGMEM 396 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 397 #endif 398 max_mapnr = highend_pfn; 399 #else 400 max_mapnr = max_low_pfn; 401 #endif 402 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 403 404 totalram_pages += free_all_bootmem(); 405 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ 406 407 reservedpages = ram = 0; 408 for (tmp = 0; tmp < max_low_pfn; tmp++) 409 if (page_is_ram(tmp)) { 410 ram++; 411 if (PageReserved(pfn_to_page(tmp))) 412 reservedpages++; 413 } 414 num_physpages = ram; 415 416 #ifdef CONFIG_HIGHMEM 417 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 418 struct page *page = pfn_to_page(tmp); 419 420 if (!page_is_ram(tmp)) { 421 SetPageReserved(page); 422 continue; 423 } 424 ClearPageReserved(page); 425 init_page_count(page); 426 __free_page(page); 427 totalhigh_pages++; 428 } 429 totalram_pages += totalhigh_pages; 430 num_physpages += totalhigh_pages; 431 #endif 432 433 codesize = (unsigned long) &_etext - (unsigned long) &_text; 434 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 435 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 436 437 #ifdef CONFIG_64BIT 438 if ((unsigned long) &_text > (unsigned long) CKSEG0) 439 /* The -4 is a hack so that user tools don't have to handle 440 the overflow. */ 441 kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4); 442 #endif 443 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT); 444 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, 445 VMALLOC_END-VMALLOC_START); 446 447 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 448 "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n", 449 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 450 ram << (PAGE_SHIFT-10), 451 codesize >> 10, 452 reservedpages << (PAGE_SHIFT-10), 453 datasize >> 10, 454 initsize >> 10, 455 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))); 456 } 457 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 458 459 void free_init_pages(const char *what, unsigned long begin, unsigned long end) 460 { 461 unsigned long pfn; 462 463 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) { 464 struct page *page = pfn_to_page(pfn); 465 void *addr = phys_to_virt(PFN_PHYS(pfn)); 466 467 ClearPageReserved(page); 468 init_page_count(page); 469 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE); 470 __free_page(page); 471 totalram_pages++; 472 } 473 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 474 } 475 476 #ifdef CONFIG_BLK_DEV_INITRD 477 void free_initrd_mem(unsigned long start, unsigned long end) 478 { 479 free_init_pages("initrd memory", 480 virt_to_phys((void *)start), 481 virt_to_phys((void *)end)); 482 } 483 #endif 484 485 void __init_refok free_initmem(void) 486 { 487 prom_free_prom_memory(); 488 free_init_pages("unused kernel memory", 489 __pa_symbol(&__init_begin), 490 __pa_symbol(&__init_end)); 491 } 492 493 unsigned long pgd_current[NR_CPUS]; 494 /* 495 * On 64-bit we've got three-level pagetables with a slightly 496 * different layout ... 497 */ 498 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order))) 499 500 /* 501 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER 502 * are constants. So we use the variants from asm-offset.h until that gcc 503 * will officially be retired. 504 */ 505 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __page_aligned(_PGD_ORDER); 506 #ifdef CONFIG_64BIT 507 #ifdef MODULE_START 508 pgd_t module_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER); 509 #endif 510 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER); 511 #endif 512 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER); 513