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 #include <linux/gfp.h> 32 #include <linux/kcore.h> 33 34 #include <asm/asm-offsets.h> 35 #include <asm/bootinfo.h> 36 #include <asm/cachectl.h> 37 #include <asm/cpu.h> 38 #include <asm/dma.h> 39 #include <asm/kmap_types.h> 40 #include <asm/mmu_context.h> 41 #include <asm/sections.h> 42 #include <asm/pgtable.h> 43 #include <asm/pgalloc.h> 44 #include <asm/tlb.h> 45 #include <asm/fixmap.h> 46 47 /* Atomicity and interruptability */ 48 #ifdef CONFIG_MIPS_MT_SMTC 49 50 #include <asm/mipsmtregs.h> 51 52 #define ENTER_CRITICAL(flags) \ 53 { \ 54 unsigned int mvpflags; \ 55 local_irq_save(flags);\ 56 mvpflags = dvpe() 57 #define EXIT_CRITICAL(flags) \ 58 evpe(mvpflags); \ 59 local_irq_restore(flags); \ 60 } 61 #else 62 63 #define ENTER_CRITICAL(flags) local_irq_save(flags) 64 #define EXIT_CRITICAL(flags) local_irq_restore(flags) 65 66 #endif /* CONFIG_MIPS_MT_SMTC */ 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 void setup_zero_pages(void) 82 { 83 unsigned int order, i; 84 struct page *page; 85 86 if (cpu_has_vce) 87 order = 3; 88 else 89 order = 0; 90 91 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 92 if (!empty_zero_page) 93 panic("Oh boy, that early out of memory?"); 94 95 page = virt_to_page((void *)empty_zero_page); 96 split_page(page, order); 97 for (i = 0; i < (1 << order); i++, page++) 98 mark_page_reserved(page); 99 100 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 101 } 102 103 #ifdef CONFIG_MIPS_MT_SMTC 104 static pte_t *kmap_coherent_pte; 105 static void __init kmap_coherent_init(void) 106 { 107 unsigned long vaddr; 108 109 /* cache the first coherent kmap pte */ 110 vaddr = __fix_to_virt(FIX_CMAP_BEGIN); 111 kmap_coherent_pte = kmap_get_fixmap_pte(vaddr); 112 } 113 #else 114 static inline void kmap_coherent_init(void) {} 115 #endif 116 117 void *kmap_coherent(struct page *page, unsigned long addr) 118 { 119 enum fixed_addresses idx; 120 unsigned long vaddr, flags, entrylo; 121 unsigned long old_ctx; 122 pte_t pte; 123 int tlbidx; 124 125 BUG_ON(Page_dcache_dirty(page)); 126 127 pagefault_disable(); 128 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); 129 #ifdef CONFIG_MIPS_MT_SMTC 130 idx += FIX_N_COLOURS * smp_processor_id() + 131 (in_interrupt() ? (FIX_N_COLOURS * NR_CPUS) : 0); 132 #else 133 idx += in_interrupt() ? FIX_N_COLOURS : 0; 134 #endif 135 vaddr = __fix_to_virt(FIX_CMAP_END - idx); 136 pte = mk_pte(page, PAGE_KERNEL); 137 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32) 138 entrylo = pte.pte_high; 139 #else 140 entrylo = pte_to_entrylo(pte_val(pte)); 141 #endif 142 143 ENTER_CRITICAL(flags); 144 old_ctx = read_c0_entryhi(); 145 write_c0_entryhi(vaddr & (PAGE_MASK << 1)); 146 write_c0_entrylo0(entrylo); 147 write_c0_entrylo1(entrylo); 148 #ifdef CONFIG_MIPS_MT_SMTC 149 set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte); 150 /* preload TLB instead of local_flush_tlb_one() */ 151 mtc0_tlbw_hazard(); 152 tlb_probe(); 153 tlb_probe_hazard(); 154 tlbidx = read_c0_index(); 155 mtc0_tlbw_hazard(); 156 if (tlbidx < 0) 157 tlb_write_random(); 158 else 159 tlb_write_indexed(); 160 #else 161 tlbidx = read_c0_wired(); 162 write_c0_wired(tlbidx + 1); 163 write_c0_index(tlbidx); 164 mtc0_tlbw_hazard(); 165 tlb_write_indexed(); 166 #endif 167 tlbw_use_hazard(); 168 write_c0_entryhi(old_ctx); 169 EXIT_CRITICAL(flags); 170 171 return (void*) vaddr; 172 } 173 174 void kunmap_coherent(void) 175 { 176 #ifndef CONFIG_MIPS_MT_SMTC 177 unsigned int wired; 178 unsigned long flags, old_ctx; 179 180 ENTER_CRITICAL(flags); 181 old_ctx = read_c0_entryhi(); 182 wired = read_c0_wired() - 1; 183 write_c0_wired(wired); 184 write_c0_index(wired); 185 write_c0_entryhi(UNIQUE_ENTRYHI(wired)); 186 write_c0_entrylo0(0); 187 write_c0_entrylo1(0); 188 mtc0_tlbw_hazard(); 189 tlb_write_indexed(); 190 tlbw_use_hazard(); 191 write_c0_entryhi(old_ctx); 192 EXIT_CRITICAL(flags); 193 #endif 194 pagefault_enable(); 195 } 196 197 void copy_user_highpage(struct page *to, struct page *from, 198 unsigned long vaddr, struct vm_area_struct *vma) 199 { 200 void *vfrom, *vto; 201 202 vto = kmap_atomic(to); 203 if (cpu_has_dc_aliases && 204 page_mapped(from) && !Page_dcache_dirty(from)) { 205 vfrom = kmap_coherent(from, vaddr); 206 copy_page(vto, vfrom); 207 kunmap_coherent(); 208 } else { 209 vfrom = kmap_atomic(from); 210 copy_page(vto, vfrom); 211 kunmap_atomic(vfrom); 212 } 213 if ((!cpu_has_ic_fills_f_dc) || 214 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) 215 flush_data_cache_page((unsigned long)vto); 216 kunmap_atomic(vto); 217 /* Make sure this page is cleared on other CPU's too before using it */ 218 smp_wmb(); 219 } 220 221 void copy_to_user_page(struct vm_area_struct *vma, 222 struct page *page, unsigned long vaddr, void *dst, const void *src, 223 unsigned long len) 224 { 225 if (cpu_has_dc_aliases && 226 page_mapped(page) && !Page_dcache_dirty(page)) { 227 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 228 memcpy(vto, src, len); 229 kunmap_coherent(); 230 } else { 231 memcpy(dst, src, len); 232 if (cpu_has_dc_aliases) 233 SetPageDcacheDirty(page); 234 } 235 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) 236 flush_cache_page(vma, vaddr, page_to_pfn(page)); 237 } 238 239 void copy_from_user_page(struct vm_area_struct *vma, 240 struct page *page, unsigned long vaddr, void *dst, const void *src, 241 unsigned long len) 242 { 243 if (cpu_has_dc_aliases && 244 page_mapped(page) && !Page_dcache_dirty(page)) { 245 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 246 memcpy(dst, vfrom, len); 247 kunmap_coherent(); 248 } else { 249 memcpy(dst, src, len); 250 if (cpu_has_dc_aliases) 251 SetPageDcacheDirty(page); 252 } 253 } 254 EXPORT_SYMBOL_GPL(copy_from_user_page); 255 256 void __init fixrange_init(unsigned long start, unsigned long end, 257 pgd_t *pgd_base) 258 { 259 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC) 260 pgd_t *pgd; 261 pud_t *pud; 262 pmd_t *pmd; 263 pte_t *pte; 264 int i, j, k; 265 unsigned long vaddr; 266 267 vaddr = start; 268 i = __pgd_offset(vaddr); 269 j = __pud_offset(vaddr); 270 k = __pmd_offset(vaddr); 271 pgd = pgd_base + i; 272 273 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) { 274 pud = (pud_t *)pgd; 275 for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) { 276 pmd = (pmd_t *)pud; 277 for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) { 278 if (pmd_none(*pmd)) { 279 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 280 set_pmd(pmd, __pmd((unsigned long)pte)); 281 BUG_ON(pte != pte_offset_kernel(pmd, 0)); 282 } 283 vaddr += PMD_SIZE; 284 } 285 k = 0; 286 } 287 j = 0; 288 } 289 #endif 290 } 291 292 #ifndef CONFIG_NEED_MULTIPLE_NODES 293 int page_is_ram(unsigned long pagenr) 294 { 295 int i; 296 297 for (i = 0; i < boot_mem_map.nr_map; i++) { 298 unsigned long addr, end; 299 300 switch (boot_mem_map.map[i].type) { 301 case BOOT_MEM_RAM: 302 case BOOT_MEM_INIT_RAM: 303 break; 304 default: 305 /* not usable memory */ 306 continue; 307 } 308 309 addr = PFN_UP(boot_mem_map.map[i].addr); 310 end = PFN_DOWN(boot_mem_map.map[i].addr + 311 boot_mem_map.map[i].size); 312 313 if (pagenr >= addr && pagenr < end) 314 return 1; 315 } 316 317 return 0; 318 } 319 320 void __init paging_init(void) 321 { 322 unsigned long max_zone_pfns[MAX_NR_ZONES]; 323 unsigned long lastpfn __maybe_unused; 324 325 pagetable_init(); 326 327 #ifdef CONFIG_HIGHMEM 328 kmap_init(); 329 #endif 330 kmap_coherent_init(); 331 332 #ifdef CONFIG_ZONE_DMA 333 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 334 #endif 335 #ifdef CONFIG_ZONE_DMA32 336 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 337 #endif 338 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 339 lastpfn = max_low_pfn; 340 #ifdef CONFIG_HIGHMEM 341 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn; 342 lastpfn = highend_pfn; 343 344 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) { 345 printk(KERN_WARNING "This processor doesn't support highmem." 346 " %ldk highmem ignored\n", 347 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10)); 348 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn; 349 lastpfn = max_low_pfn; 350 } 351 #endif 352 353 free_area_init_nodes(max_zone_pfns); 354 } 355 356 #ifdef CONFIG_64BIT 357 static struct kcore_list kcore_kseg0; 358 #endif 359 360 static inline void mem_init_free_highmem(void) 361 { 362 #ifdef CONFIG_HIGHMEM 363 unsigned long tmp; 364 365 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 366 struct page *page = pfn_to_page(tmp); 367 368 if (!page_is_ram(tmp)) 369 SetPageReserved(page); 370 else 371 free_highmem_page(page); 372 } 373 #endif 374 } 375 376 void __init mem_init(void) 377 { 378 #ifdef CONFIG_HIGHMEM 379 #ifdef CONFIG_DISCONTIGMEM 380 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 381 #endif 382 max_mapnr = highend_pfn ? highend_pfn : max_low_pfn; 383 #else 384 max_mapnr = max_low_pfn; 385 #endif 386 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 387 388 free_all_bootmem(); 389 setup_zero_pages(); /* Setup zeroed pages. */ 390 mem_init_free_highmem(); 391 mem_init_print_info(NULL); 392 393 #ifdef CONFIG_64BIT 394 if ((unsigned long) &_text > (unsigned long) CKSEG0) 395 /* The -4 is a hack so that user tools don't have to handle 396 the overflow. */ 397 kclist_add(&kcore_kseg0, (void *) CKSEG0, 398 0x80000000 - 4, KCORE_TEXT); 399 #endif 400 } 401 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 402 403 void free_init_pages(const char *what, unsigned long begin, unsigned long end) 404 { 405 unsigned long pfn; 406 407 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) { 408 struct page *page = pfn_to_page(pfn); 409 void *addr = phys_to_virt(PFN_PHYS(pfn)); 410 411 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE); 412 free_reserved_page(page); 413 } 414 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 415 } 416 417 #ifdef CONFIG_BLK_DEV_INITRD 418 void free_initrd_mem(unsigned long start, unsigned long end) 419 { 420 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM, 421 "initrd"); 422 } 423 #endif 424 425 void __init_refok free_initmem(void) 426 { 427 prom_free_prom_memory(); 428 free_initmem_default(POISON_FREE_INITMEM); 429 } 430 431 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT 432 unsigned long pgd_current[NR_CPUS]; 433 #endif 434 435 /* 436 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER 437 * are constants. So we use the variants from asm-offset.h until that gcc 438 * will officially be retired. 439 * 440 * Align swapper_pg_dir in to 64K, allows its address to be loaded 441 * with a single LUI instruction in the TLB handlers. If we used 442 * __aligned(64K), its size would get rounded up to the alignment 443 * size, and waste space. So we place it in its own section and align 444 * it in the linker script. 445 */ 446 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(.bss..swapper_pg_dir); 447 #ifndef __PAGETABLE_PMD_FOLDED 448 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss; 449 #endif 450 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss; 451