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 EXPORT_SYMBOL_GPL(empty_zero_page); 75 76 /* 77 * Not static inline because used by IP27 special magic initialization code 78 */ 79 unsigned long setup_zero_pages(void) 80 { 81 unsigned int order; 82 unsigned long size; 83 struct page *page; 84 85 if (cpu_has_vce) 86 order = 3; 87 else 88 order = 0; 89 90 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 91 if (!empty_zero_page) 92 panic("Oh boy, that early out of memory?"); 93 94 page = virt_to_page((void *)empty_zero_page); 95 split_page(page, order); 96 while (page < virt_to_page((void *)(empty_zero_page + (PAGE_SIZE << order)))) { 97 SetPageReserved(page); 98 page++; 99 } 100 101 size = PAGE_SIZE << order; 102 zero_page_mask = (size - 1) & PAGE_MASK; 103 104 return 1UL << order; 105 } 106 107 #ifdef CONFIG_MIPS_MT_SMTC 108 static pte_t *kmap_coherent_pte; 109 static void __init kmap_coherent_init(void) 110 { 111 unsigned long vaddr; 112 113 /* cache the first coherent kmap pte */ 114 vaddr = __fix_to_virt(FIX_CMAP_BEGIN); 115 kmap_coherent_pte = kmap_get_fixmap_pte(vaddr); 116 } 117 #else 118 static inline void kmap_coherent_init(void) {} 119 #endif 120 121 void *kmap_coherent(struct page *page, unsigned long addr) 122 { 123 enum fixed_addresses idx; 124 unsigned long vaddr, flags, entrylo; 125 unsigned long old_ctx; 126 pte_t pte; 127 int tlbidx; 128 129 BUG_ON(Page_dcache_dirty(page)); 130 131 inc_preempt_count(); 132 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); 133 #ifdef CONFIG_MIPS_MT_SMTC 134 idx += FIX_N_COLOURS * smp_processor_id(); 135 #endif 136 vaddr = __fix_to_virt(FIX_CMAP_END - idx); 137 pte = mk_pte(page, PAGE_KERNEL); 138 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32) 139 entrylo = pte.pte_high; 140 #else 141 entrylo = pte_val(pte) >> 6; 142 #endif 143 144 ENTER_CRITICAL(flags); 145 old_ctx = read_c0_entryhi(); 146 write_c0_entryhi(vaddr & (PAGE_MASK << 1)); 147 write_c0_entrylo0(entrylo); 148 write_c0_entrylo1(entrylo); 149 #ifdef CONFIG_MIPS_MT_SMTC 150 set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte); 151 /* preload TLB instead of local_flush_tlb_one() */ 152 mtc0_tlbw_hazard(); 153 tlb_probe(); 154 tlb_probe_hazard(); 155 tlbidx = read_c0_index(); 156 mtc0_tlbw_hazard(); 157 if (tlbidx < 0) 158 tlb_write_random(); 159 else 160 tlb_write_indexed(); 161 #else 162 tlbidx = read_c0_wired(); 163 write_c0_wired(tlbidx + 1); 164 write_c0_index(tlbidx); 165 mtc0_tlbw_hazard(); 166 tlb_write_indexed(); 167 #endif 168 tlbw_use_hazard(); 169 write_c0_entryhi(old_ctx); 170 EXIT_CRITICAL(flags); 171 172 return (void*) vaddr; 173 } 174 175 #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1))) 176 177 void kunmap_coherent(void) 178 { 179 #ifndef CONFIG_MIPS_MT_SMTC 180 unsigned int wired; 181 unsigned long flags, old_ctx; 182 183 ENTER_CRITICAL(flags); 184 old_ctx = read_c0_entryhi(); 185 wired = read_c0_wired() - 1; 186 write_c0_wired(wired); 187 write_c0_index(wired); 188 write_c0_entryhi(UNIQUE_ENTRYHI(wired)); 189 write_c0_entrylo0(0); 190 write_c0_entrylo1(0); 191 mtc0_tlbw_hazard(); 192 tlb_write_indexed(); 193 tlbw_use_hazard(); 194 write_c0_entryhi(old_ctx); 195 EXIT_CRITICAL(flags); 196 #endif 197 dec_preempt_count(); 198 preempt_check_resched(); 199 } 200 201 void copy_user_highpage(struct page *to, struct page *from, 202 unsigned long vaddr, struct vm_area_struct *vma) 203 { 204 void *vfrom, *vto; 205 206 vto = kmap_atomic(to, KM_USER1); 207 if (cpu_has_dc_aliases && 208 page_mapped(from) && !Page_dcache_dirty(from)) { 209 vfrom = kmap_coherent(from, vaddr); 210 copy_page(vto, vfrom); 211 kunmap_coherent(); 212 } else { 213 vfrom = kmap_atomic(from, KM_USER0); 214 copy_page(vto, vfrom); 215 kunmap_atomic(vfrom, KM_USER0); 216 } 217 if ((!cpu_has_ic_fills_f_dc) || 218 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) 219 flush_data_cache_page((unsigned long)vto); 220 kunmap_atomic(vto, KM_USER1); 221 /* Make sure this page is cleared on other CPU's too before using it */ 222 smp_wmb(); 223 } 224 225 void copy_to_user_page(struct vm_area_struct *vma, 226 struct page *page, unsigned long vaddr, void *dst, const void *src, 227 unsigned long len) 228 { 229 if (cpu_has_dc_aliases && 230 page_mapped(page) && !Page_dcache_dirty(page)) { 231 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 232 memcpy(vto, src, len); 233 kunmap_coherent(); 234 } else { 235 memcpy(dst, src, len); 236 if (cpu_has_dc_aliases) 237 SetPageDcacheDirty(page); 238 } 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 void copy_from_user_page(struct vm_area_struct *vma, 244 struct page *page, unsigned long vaddr, void *dst, const void *src, 245 unsigned long len) 246 { 247 if (cpu_has_dc_aliases && 248 page_mapped(page) && !Page_dcache_dirty(page)) { 249 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 250 memcpy(dst, vfrom, len); 251 kunmap_coherent(); 252 } else { 253 memcpy(dst, src, len); 254 if (cpu_has_dc_aliases) 255 SetPageDcacheDirty(page); 256 } 257 } 258 259 void __init fixrange_init(unsigned long start, unsigned long end, 260 pgd_t *pgd_base) 261 { 262 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC) 263 pgd_t *pgd; 264 pud_t *pud; 265 pmd_t *pmd; 266 pte_t *pte; 267 int i, j, k; 268 unsigned long vaddr; 269 270 vaddr = start; 271 i = __pgd_offset(vaddr); 272 j = __pud_offset(vaddr); 273 k = __pmd_offset(vaddr); 274 pgd = pgd_base + i; 275 276 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { 277 pud = (pud_t *)pgd; 278 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) { 279 pmd = (pmd_t *)pud; 280 for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) { 281 if (pmd_none(*pmd)) { 282 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 283 set_pmd(pmd, __pmd((unsigned long)pte)); 284 BUG_ON(pte != pte_offset_kernel(pmd, 0)); 285 } 286 vaddr += PMD_SIZE; 287 } 288 k = 0; 289 } 290 j = 0; 291 } 292 #endif 293 } 294 295 #ifndef CONFIG_NEED_MULTIPLE_NODES 296 static int __init page_is_ram(unsigned long pagenr) 297 { 298 int i; 299 300 for (i = 0; i < boot_mem_map.nr_map; i++) { 301 unsigned long addr, end; 302 303 if (boot_mem_map.map[i].type != BOOT_MEM_RAM) 304 /* not usable memory */ 305 continue; 306 307 addr = PFN_UP(boot_mem_map.map[i].addr); 308 end = PFN_DOWN(boot_mem_map.map[i].addr + 309 boot_mem_map.map[i].size); 310 311 if (pagenr >= addr && pagenr < end) 312 return 1; 313 } 314 315 return 0; 316 } 317 318 void __init paging_init(void) 319 { 320 unsigned long max_zone_pfns[MAX_NR_ZONES]; 321 unsigned long lastpfn; 322 323 pagetable_init(); 324 325 #ifdef CONFIG_HIGHMEM 326 kmap_init(); 327 #endif 328 kmap_coherent_init(); 329 330 #ifdef CONFIG_ZONE_DMA 331 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 332 #endif 333 #ifdef CONFIG_ZONE_DMA32 334 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 335 #endif 336 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 337 lastpfn = max_low_pfn; 338 #ifdef CONFIG_HIGHMEM 339 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn; 340 lastpfn = highend_pfn; 341 342 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) { 343 printk(KERN_WARNING "This processor doesn't support highmem." 344 " %ldk highmem ignored\n", 345 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10)); 346 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn; 347 lastpfn = max_low_pfn; 348 } 349 #endif 350 351 free_area_init_nodes(max_zone_pfns); 352 } 353 354 static struct kcore_list kcore_mem, kcore_vmalloc; 355 #ifdef CONFIG_64BIT 356 static struct kcore_list kcore_kseg0; 357 #endif 358 359 void __init mem_init(void) 360 { 361 unsigned long codesize, reservedpages, datasize, initsize; 362 unsigned long tmp, ram; 363 364 #ifdef CONFIG_HIGHMEM 365 #ifdef CONFIG_DISCONTIGMEM 366 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 367 #endif 368 max_mapnr = highend_pfn; 369 #else 370 max_mapnr = max_low_pfn; 371 #endif 372 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 373 374 totalram_pages += free_all_bootmem(); 375 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ 376 377 reservedpages = ram = 0; 378 for (tmp = 0; tmp < max_low_pfn; tmp++) 379 if (page_is_ram(tmp)) { 380 ram++; 381 if (PageReserved(pfn_to_page(tmp))) 382 reservedpages++; 383 } 384 num_physpages = ram; 385 386 #ifdef CONFIG_HIGHMEM 387 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 388 struct page *page = pfn_to_page(tmp); 389 390 if (!page_is_ram(tmp)) { 391 SetPageReserved(page); 392 continue; 393 } 394 ClearPageReserved(page); 395 init_page_count(page); 396 __free_page(page); 397 totalhigh_pages++; 398 } 399 totalram_pages += totalhigh_pages; 400 num_physpages += totalhigh_pages; 401 #endif 402 403 codesize = (unsigned long) &_etext - (unsigned long) &_text; 404 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 405 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 406 407 #ifdef CONFIG_64BIT 408 if ((unsigned long) &_text > (unsigned long) CKSEG0) 409 /* The -4 is a hack so that user tools don't have to handle 410 the overflow. */ 411 kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4); 412 #endif 413 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT); 414 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, 415 VMALLOC_END-VMALLOC_START); 416 417 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 418 "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n", 419 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 420 ram << (PAGE_SHIFT-10), 421 codesize >> 10, 422 reservedpages << (PAGE_SHIFT-10), 423 datasize >> 10, 424 initsize >> 10, 425 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))); 426 } 427 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 428 429 void free_init_pages(const char *what, unsigned long begin, unsigned long end) 430 { 431 unsigned long pfn; 432 433 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) { 434 struct page *page = pfn_to_page(pfn); 435 void *addr = phys_to_virt(PFN_PHYS(pfn)); 436 437 ClearPageReserved(page); 438 init_page_count(page); 439 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE); 440 __free_page(page); 441 totalram_pages++; 442 } 443 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 444 } 445 446 #ifdef CONFIG_BLK_DEV_INITRD 447 void free_initrd_mem(unsigned long start, unsigned long end) 448 { 449 free_init_pages("initrd memory", 450 virt_to_phys((void *)start), 451 virt_to_phys((void *)end)); 452 } 453 #endif 454 455 void __init_refok free_initmem(void) 456 { 457 prom_free_prom_memory(); 458 free_init_pages("unused kernel memory", 459 __pa_symbol(&__init_begin), 460 __pa_symbol(&__init_end)); 461 } 462 463 unsigned long pgd_current[NR_CPUS]; 464 /* 465 * On 64-bit we've got three-level pagetables with a slightly 466 * different layout ... 467 */ 468 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order))) 469 470 /* 471 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER 472 * are constants. So we use the variants from asm-offset.h until that gcc 473 * will officially be retired. 474 */ 475 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __page_aligned(_PGD_ORDER); 476 #ifdef CONFIG_64BIT 477 #ifdef MODULE_START 478 pgd_t module_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER); 479 #endif 480 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER); 481 #endif 482 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER); 483