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/smp.h> 17 #include <linux/kernel.h> 18 #include <linux/errno.h> 19 #include <linux/string.h> 20 #include <linux/types.h> 21 #include <linux/pagemap.h> 22 #include <linux/ptrace.h> 23 #include <linux/mman.h> 24 #include <linux/mm.h> 25 #include <linux/bootmem.h> 26 #include <linux/highmem.h> 27 #include <linux/swap.h> 28 #include <linux/proc_fs.h> 29 #include <linux/pfn.h> 30 #include <linux/hardirq.h> 31 32 #include <asm/asm-offsets.h> 33 #include <asm/bootinfo.h> 34 #include <asm/cachectl.h> 35 #include <asm/cpu.h> 36 #include <asm/dma.h> 37 #include <asm/kmap_types.h> 38 #include <asm/mmu_context.h> 39 #include <asm/sections.h> 40 #include <asm/pgtable.h> 41 #include <asm/pgalloc.h> 42 #include <asm/tlb.h> 43 #include <asm/fixmap.h> 44 45 /* Atomicity and interruptability */ 46 #ifdef CONFIG_MIPS_MT_SMTC 47 48 #include <asm/mipsmtregs.h> 49 50 #define ENTER_CRITICAL(flags) \ 51 { \ 52 unsigned int mvpflags; \ 53 local_irq_save(flags);\ 54 mvpflags = dvpe() 55 #define EXIT_CRITICAL(flags) \ 56 evpe(mvpflags); \ 57 local_irq_restore(flags); \ 58 } 59 #else 60 61 #define ENTER_CRITICAL(flags) local_irq_save(flags) 62 #define EXIT_CRITICAL(flags) local_irq_restore(flags) 63 64 #endif /* CONFIG_MIPS_MT_SMTC */ 65 66 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 67 68 /* 69 * We have up to 8 empty zeroed pages so we can map one of the right colour 70 * when needed. This is necessary only on R4000 / R4400 SC and MC versions 71 * where we have to avoid VCED / VECI exceptions for good performance at 72 * any price. Since page is never written to after the initialization we 73 * don't have to care about aliases on other CPUs. 74 */ 75 unsigned long empty_zero_page, zero_page_mask; 76 EXPORT_SYMBOL_GPL(empty_zero_page); 77 78 /* 79 * Not static inline because used by IP27 special magic initialization code 80 */ 81 unsigned long setup_zero_pages(void) 82 { 83 unsigned int order; 84 unsigned long size; 85 struct page *page; 86 87 if (cpu_has_vce) 88 order = 3; 89 else 90 order = 0; 91 92 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 93 if (!empty_zero_page) 94 panic("Oh boy, that early out of memory?"); 95 96 page = virt_to_page((void *)empty_zero_page); 97 split_page(page, order); 98 while (page < virt_to_page((void *)(empty_zero_page + (PAGE_SIZE << order)))) { 99 SetPageReserved(page); 100 page++; 101 } 102 103 size = PAGE_SIZE << order; 104 zero_page_mask = (size - 1) & PAGE_MASK; 105 106 return 1UL << order; 107 } 108 109 #ifdef CONFIG_MIPS_MT_SMTC 110 static pte_t *kmap_coherent_pte; 111 static void __init kmap_coherent_init(void) 112 { 113 unsigned long vaddr; 114 115 /* cache the first coherent kmap pte */ 116 vaddr = __fix_to_virt(FIX_CMAP_BEGIN); 117 kmap_coherent_pte = kmap_get_fixmap_pte(vaddr); 118 } 119 #else 120 static inline void kmap_coherent_init(void) {} 121 #endif 122 123 void *kmap_coherent(struct page *page, unsigned long addr) 124 { 125 enum fixed_addresses idx; 126 unsigned long vaddr, flags, entrylo; 127 unsigned long old_ctx; 128 pte_t pte; 129 int tlbidx; 130 131 BUG_ON(Page_dcache_dirty(page)); 132 133 inc_preempt_count(); 134 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); 135 #ifdef CONFIG_MIPS_MT_SMTC 136 idx += FIX_N_COLOURS * smp_processor_id() + 137 (in_interrupt() ? (FIX_N_COLOURS * NR_CPUS) : 0); 138 #else 139 idx += in_interrupt() ? FIX_N_COLOURS : 0; 140 #endif 141 vaddr = __fix_to_virt(FIX_CMAP_END - idx); 142 pte = mk_pte(page, PAGE_KERNEL); 143 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32) 144 entrylo = pte.pte_high; 145 #else 146 entrylo = pte_val(pte) >> 6; 147 #endif 148 149 ENTER_CRITICAL(flags); 150 old_ctx = read_c0_entryhi(); 151 write_c0_entryhi(vaddr & (PAGE_MASK << 1)); 152 write_c0_entrylo0(entrylo); 153 write_c0_entrylo1(entrylo); 154 #ifdef CONFIG_MIPS_MT_SMTC 155 set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte); 156 /* preload TLB instead of local_flush_tlb_one() */ 157 mtc0_tlbw_hazard(); 158 tlb_probe(); 159 tlb_probe_hazard(); 160 tlbidx = read_c0_index(); 161 mtc0_tlbw_hazard(); 162 if (tlbidx < 0) 163 tlb_write_random(); 164 else 165 tlb_write_indexed(); 166 #else 167 tlbidx = read_c0_wired(); 168 write_c0_wired(tlbidx + 1); 169 write_c0_index(tlbidx); 170 mtc0_tlbw_hazard(); 171 tlb_write_indexed(); 172 #endif 173 tlbw_use_hazard(); 174 write_c0_entryhi(old_ctx); 175 EXIT_CRITICAL(flags); 176 177 return (void*) vaddr; 178 } 179 180 #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1))) 181 182 void kunmap_coherent(void) 183 { 184 #ifndef CONFIG_MIPS_MT_SMTC 185 unsigned int wired; 186 unsigned long flags, old_ctx; 187 188 ENTER_CRITICAL(flags); 189 old_ctx = read_c0_entryhi(); 190 wired = read_c0_wired() - 1; 191 write_c0_wired(wired); 192 write_c0_index(wired); 193 write_c0_entryhi(UNIQUE_ENTRYHI(wired)); 194 write_c0_entrylo0(0); 195 write_c0_entrylo1(0); 196 mtc0_tlbw_hazard(); 197 tlb_write_indexed(); 198 tlbw_use_hazard(); 199 write_c0_entryhi(old_ctx); 200 EXIT_CRITICAL(flags); 201 #endif 202 dec_preempt_count(); 203 preempt_check_resched(); 204 } 205 206 void copy_user_highpage(struct page *to, struct page *from, 207 unsigned long vaddr, struct vm_area_struct *vma) 208 { 209 void *vfrom, *vto; 210 211 vto = kmap_atomic(to, KM_USER1); 212 if (cpu_has_dc_aliases && 213 page_mapped(from) && !Page_dcache_dirty(from)) { 214 vfrom = kmap_coherent(from, vaddr); 215 copy_page(vto, vfrom); 216 kunmap_coherent(); 217 } else { 218 vfrom = kmap_atomic(from, KM_USER0); 219 copy_page(vto, vfrom); 220 kunmap_atomic(vfrom, KM_USER0); 221 } 222 if ((!cpu_has_ic_fills_f_dc) || 223 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) 224 flush_data_cache_page((unsigned long)vto); 225 kunmap_atomic(vto, KM_USER1); 226 /* Make sure this page is cleared on other CPU's too before using it */ 227 smp_wmb(); 228 } 229 230 void copy_to_user_page(struct vm_area_struct *vma, 231 struct page *page, unsigned long vaddr, void *dst, const void *src, 232 unsigned long len) 233 { 234 if (cpu_has_dc_aliases && 235 page_mapped(page) && !Page_dcache_dirty(page)) { 236 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 237 memcpy(vto, src, len); 238 kunmap_coherent(); 239 } else { 240 memcpy(dst, src, len); 241 if (cpu_has_dc_aliases) 242 SetPageDcacheDirty(page); 243 } 244 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) 245 flush_cache_page(vma, vaddr, page_to_pfn(page)); 246 } 247 248 void copy_from_user_page(struct vm_area_struct *vma, 249 struct page *page, unsigned long vaddr, void *dst, const void *src, 250 unsigned long len) 251 { 252 if (cpu_has_dc_aliases && 253 page_mapped(page) && !Page_dcache_dirty(page)) { 254 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 255 memcpy(dst, vfrom, len); 256 kunmap_coherent(); 257 } else { 258 memcpy(dst, src, len); 259 if (cpu_has_dc_aliases) 260 SetPageDcacheDirty(page); 261 } 262 } 263 264 void __init fixrange_init(unsigned long start, unsigned long end, 265 pgd_t *pgd_base) 266 { 267 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC) 268 pgd_t *pgd; 269 pud_t *pud; 270 pmd_t *pmd; 271 pte_t *pte; 272 int i, j, k; 273 unsigned long vaddr; 274 275 vaddr = start; 276 i = __pgd_offset(vaddr); 277 j = __pud_offset(vaddr); 278 k = __pmd_offset(vaddr); 279 pgd = pgd_base + i; 280 281 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { 282 pud = (pud_t *)pgd; 283 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) { 284 pmd = (pmd_t *)pud; 285 for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) { 286 if (pmd_none(*pmd)) { 287 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 288 set_pmd(pmd, __pmd((unsigned long)pte)); 289 BUG_ON(pte != pte_offset_kernel(pmd, 0)); 290 } 291 vaddr += PMD_SIZE; 292 } 293 k = 0; 294 } 295 j = 0; 296 } 297 #endif 298 } 299 300 #ifndef CONFIG_NEED_MULTIPLE_NODES 301 static int __init page_is_ram(unsigned long pagenr) 302 { 303 int i; 304 305 for (i = 0; i < boot_mem_map.nr_map; i++) { 306 unsigned long addr, end; 307 308 if (boot_mem_map.map[i].type != BOOT_MEM_RAM) 309 /* not usable memory */ 310 continue; 311 312 addr = PFN_UP(boot_mem_map.map[i].addr); 313 end = PFN_DOWN(boot_mem_map.map[i].addr + 314 boot_mem_map.map[i].size); 315 316 if (pagenr >= addr && pagenr < end) 317 return 1; 318 } 319 320 return 0; 321 } 322 323 void __init paging_init(void) 324 { 325 unsigned long max_zone_pfns[MAX_NR_ZONES]; 326 unsigned long lastpfn; 327 328 pagetable_init(); 329 330 #ifdef CONFIG_HIGHMEM 331 kmap_init(); 332 #endif 333 kmap_coherent_init(); 334 335 #ifdef CONFIG_ZONE_DMA 336 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 337 #endif 338 #ifdef CONFIG_ZONE_DMA32 339 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 340 #endif 341 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 342 lastpfn = max_low_pfn; 343 #ifdef CONFIG_HIGHMEM 344 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn; 345 lastpfn = highend_pfn; 346 347 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) { 348 printk(KERN_WARNING "This processor doesn't support highmem." 349 " %ldk highmem ignored\n", 350 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10)); 351 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn; 352 lastpfn = max_low_pfn; 353 } 354 #endif 355 356 free_area_init_nodes(max_zone_pfns); 357 } 358 359 #ifdef CONFIG_64BIT 360 static struct kcore_list kcore_kseg0; 361 #endif 362 363 void __init mem_init(void) 364 { 365 unsigned long codesize, reservedpages, datasize, initsize; 366 unsigned long tmp, ram; 367 368 #ifdef CONFIG_HIGHMEM 369 #ifdef CONFIG_DISCONTIGMEM 370 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 371 #endif 372 max_mapnr = highend_pfn; 373 #else 374 max_mapnr = max_low_pfn; 375 #endif 376 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 377 378 totalram_pages += free_all_bootmem(); 379 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ 380 381 reservedpages = ram = 0; 382 for (tmp = 0; tmp < max_low_pfn; tmp++) 383 if (page_is_ram(tmp)) { 384 ram++; 385 if (PageReserved(pfn_to_page(tmp))) 386 reservedpages++; 387 } 388 num_physpages = ram; 389 390 #ifdef CONFIG_HIGHMEM 391 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 392 struct page *page = pfn_to_page(tmp); 393 394 if (!page_is_ram(tmp)) { 395 SetPageReserved(page); 396 continue; 397 } 398 ClearPageReserved(page); 399 init_page_count(page); 400 __free_page(page); 401 totalhigh_pages++; 402 } 403 totalram_pages += totalhigh_pages; 404 num_physpages += totalhigh_pages; 405 #endif 406 407 codesize = (unsigned long) &_etext - (unsigned long) &_text; 408 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 409 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 410 411 #ifdef CONFIG_64BIT 412 if ((unsigned long) &_text > (unsigned long) CKSEG0) 413 /* The -4 is a hack so that user tools don't have to handle 414 the overflow. */ 415 kclist_add(&kcore_kseg0, (void *) CKSEG0, 416 0x80000000 - 4, KCORE_TEXT); 417 #endif 418 419 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 420 "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n", 421 nr_free_pages() << (PAGE_SHIFT-10), 422 ram << (PAGE_SHIFT-10), 423 codesize >> 10, 424 reservedpages << (PAGE_SHIFT-10), 425 datasize >> 10, 426 initsize >> 10, 427 totalhigh_pages << (PAGE_SHIFT-10)); 428 } 429 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 430 431 void free_init_pages(const char *what, unsigned long begin, unsigned long end) 432 { 433 unsigned long pfn; 434 435 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) { 436 struct page *page = pfn_to_page(pfn); 437 void *addr = phys_to_virt(PFN_PHYS(pfn)); 438 439 ClearPageReserved(page); 440 init_page_count(page); 441 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE); 442 __free_page(page); 443 totalram_pages++; 444 } 445 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 446 } 447 448 #ifdef CONFIG_BLK_DEV_INITRD 449 void free_initrd_mem(unsigned long start, unsigned long end) 450 { 451 free_init_pages("initrd memory", 452 virt_to_phys((void *)start), 453 virt_to_phys((void *)end)); 454 } 455 #endif 456 457 void __init_refok free_initmem(void) 458 { 459 prom_free_prom_memory(); 460 free_init_pages("unused kernel memory", 461 __pa_symbol(&__init_begin), 462 __pa_symbol(&__init_end)); 463 } 464 465 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT 466 unsigned long pgd_current[NR_CPUS]; 467 #endif 468 /* 469 * On 64-bit we've got three-level pagetables with a slightly 470 * different layout ... 471 */ 472 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order))) 473 474 /* 475 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER 476 * are constants. So we use the variants from asm-offset.h until that gcc 477 * will officially be retired. 478 */ 479 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __page_aligned(_PGD_ORDER); 480 #ifdef CONFIG_64BIT 481 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER); 482 #endif 483 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER); 484