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   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/init.h>
  12 #include <linux/module.h>
  13 #include <linux/signal.h>
  14 #include <linux/sched.h>
  15 #include <linux/kernel.h>
  16 #include <linux/errno.h>
  17 #include <linux/string.h>
  18 #include <linux/types.h>
  19 #include <linux/pagemap.h>
  20 #include <linux/ptrace.h>
  21 #include <linux/mman.h>
  22 #include <linux/mm.h>
  23 #include <linux/bootmem.h>
  24 #include <linux/highmem.h>
  25 #include <linux/swap.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/pfn.h>
  28
  29 #include <asm/bootinfo.h>
  30 #include <asm/cachectl.h>
  31 #include <asm/cpu.h>
  32 #include <asm/dma.h>
  33 #include <asm/kmap_types.h>
  34 #include <asm/mmu_context.h>
  35 #include <asm/sections.h>
  36 #include <asm/pgtable.h>
  37 #include <asm/pgalloc.h>
  38 #include <asm/tlb.h>
  39 #include <asm/fixmap.h>
  40
  41 /* Atomicity and interruptability */
  42 #ifdef CONFIG_MIPS_MT_SMTC
  43
  44 #include <asm/mipsmtregs.h>
  45
  46 #define ENTER_CRITICAL(flags) \
  47         { \
  48         unsigned int mvpflags; \
  49         local_irq_save(flags);\
  50         mvpflags = dvpe()
  51 #define EXIT_CRITICAL(flags) \
  52         evpe(mvpflags); \
  53         local_irq_restore(flags); \
  54         }
  55 #else
  56
  57 #define ENTER_CRITICAL(flags) local_irq_save(flags)
  58 #define EXIT_CRITICAL(flags) local_irq_restore(flags)
  59
  60 #endif /* CONFIG_MIPS_MT_SMTC */
  61
  62 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  63
  64 unsigned long highstart_pfn, highend_pfn;
  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 static inline 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         inc_preempt_count();
 137         idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
 138 #ifdef CONFIG_MIPS_MT_SMTC
 139         idx += FIX_N_COLOURS * smp_processor_id();
 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_R1)
 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 static inline void kunmap_coherent(struct page *page)
 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                 vfrom = kmap_coherent(from, vaddr);
 214                 copy_page(vto, vfrom);
 215                 kunmap_coherent(from);
 216         } else {
 217                 vfrom = kmap_atomic(from, KM_USER0);
 218                 copy_page(vto, vfrom);
 219                 kunmap_atomic(vfrom, KM_USER0);
 220         }
 221         if (((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) ||
 222             pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
 223                 flush_data_cache_page((unsigned long)vto);
 224         kunmap_atomic(vto, KM_USER1);
 225         /* Make sure this page is cleared on other CPU's too before using it */
 226         smp_wmb();
 227 }
 228
 229 EXPORT_SYMBOL(copy_user_highpage);
 230
 231 void copy_to_user_page(struct vm_area_struct *vma,
 232         struct page *page, unsigned long vaddr, void *dst, const void *src,
 233         unsigned long len)
 234 {
 235         if (cpu_has_dc_aliases) {
 236                 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 237                 memcpy(vto, src, len);
 238                 kunmap_coherent(page);
 239         } else
 240                 memcpy(dst, src, len);
 241         if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
 242                 flush_cache_page(vma, vaddr, page_to_pfn(page));
 243 }
 244
 245 EXPORT_SYMBOL(copy_to_user_page);
 246
 247 void copy_from_user_page(struct vm_area_struct *vma,
 248         struct page *page, unsigned long vaddr, void *dst, const void *src,
 249         unsigned long len)
 250 {
 251         if (cpu_has_dc_aliases) {
 252                 void *vfrom =
 253                         kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 254                 memcpy(dst, vfrom, len);
 255                 kunmap_coherent(page);
 256         } else
 257                 memcpy(dst, src, len);
 258 }
 259
 260 EXPORT_SYMBOL(copy_from_user_page);
 261
 262
 263 #ifdef CONFIG_HIGHMEM
 264 pte_t *kmap_pte;
 265 pgprot_t kmap_prot;
 266
 267 static void __init kmap_init(void)
 268 {
 269         unsigned long kmap_vstart;
 270
 271         /* cache the first kmap pte */
 272         kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
 273         kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
 274
 275         kmap_prot = PAGE_KERNEL;
 276 }
 277 #endif /* CONFIG_HIGHMEM */
 278
 279 void __init fixrange_init(unsigned long start, unsigned long end,
 280         pgd_t *pgd_base)
 281 {
 282 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC)
 283         pgd_t *pgd;
 284         pud_t *pud;
 285         pmd_t *pmd;
 286         pte_t *pte;
 287         int i, j, k;
 288         unsigned long vaddr;
 289
 290         vaddr = start;
 291         i = __pgd_offset(vaddr);
 292         j = __pud_offset(vaddr);
 293         k = __pmd_offset(vaddr);
 294         pgd = pgd_base + i;
 295
 296         for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
 297                 pud = (pud_t *)pgd;
 298                 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
 299                         pmd = (pmd_t *)pud;
 300                         for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
 301                                 if (pmd_none(*pmd)) {
 302                                         pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
 303                                         set_pmd(pmd, __pmd((unsigned long)pte));
 304                                         if (pte != pte_offset_kernel(pmd, 0))
 305                                                 BUG();
 306                                 }
 307                                 vaddr += PMD_SIZE;
 308                         }
 309                         k = 0;
 310                 }
 311                 j = 0;
 312         }
 313 #endif
 314 }
 315
 316 #ifndef CONFIG_NEED_MULTIPLE_NODES
 317 extern void pagetable_init(void);
 318
 319 static int __init page_is_ram(unsigned long pagenr)
 320 {
 321         int i;
 322
 323         for (i = 0; i < boot_mem_map.nr_map; i++) {
 324                 unsigned long addr, end;
 325
 326                 if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
 327                         /* not usable memory */
 328                         continue;
 329
 330                 addr = PFN_UP(boot_mem_map.map[i].addr);
 331                 end = PFN_DOWN(boot_mem_map.map[i].addr +
 332                                boot_mem_map.map[i].size);
 333
 334                 if (pagenr >= addr && pagenr < end)
 335                         return 1;
 336         }
 337
 338         return 0;
 339 }
 340
 341 void __init paging_init(void)
 342 {
 343         unsigned long zones_size[MAX_NR_ZONES] = { 0, };
 344         unsigned long max_dma, low;
 345 #ifndef CONFIG_FLATMEM
 346         unsigned long zholes_size[MAX_NR_ZONES] = { 0, };
 347         unsigned long i, j, pfn;
 348 #endif
 349
 350         pagetable_init();
 351
 352 #ifdef CONFIG_HIGHMEM
 353         kmap_init();
 354 #endif
 355         kmap_coherent_init();
 356
 357         max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 358         low = max_low_pfn;
 359
 360 #ifdef CONFIG_ISA
 361         if (low < max_dma)
 362                 zones_size[ZONE_DMA] = low;
 363         else {
 364                 zones_size[ZONE_DMA] = max_dma;
 365                 zones_size[ZONE_NORMAL] = low - max_dma;
 366         }
 367 #else
 368         zones_size[ZONE_DMA] = low;
 369 #endif
 370 #ifdef CONFIG_HIGHMEM
 371         zones_size[ZONE_HIGHMEM] = highend_pfn - highstart_pfn;
 372
 373         if (cpu_has_dc_aliases && zones_size[ZONE_HIGHMEM]) {
 374                 printk(KERN_WARNING "This processor doesn't support highmem."
 375                        " %ldk highmem ignored\n", zones_size[ZONE_HIGHMEM]);
 376                 zones_size[ZONE_HIGHMEM] = 0;
 377         }
 378 #endif
 379
 380 #ifdef CONFIG_FLATMEM
 381         free_area_init(zones_size);
 382 #else
 383         pfn = 0;
 384         for (i = 0; i < MAX_NR_ZONES; i++)
 385                 for (j = 0; j < zones_size[i]; j++, pfn++)
 386                         if (!page_is_ram(pfn))
 387                                 zholes_size[i]++;
 388         free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size);
 389 #endif
 390 }
 391
 392 static struct kcore_list kcore_mem, kcore_vmalloc;
 393 #ifdef CONFIG_64BIT
 394 static struct kcore_list kcore_kseg0;
 395 #endif
 396
 397 void __init mem_init(void)
 398 {
 399         unsigned long codesize, reservedpages, datasize, initsize;
 400         unsigned long tmp, ram;
 401
 402 #ifdef CONFIG_HIGHMEM
 403 #ifdef CONFIG_DISCONTIGMEM
 404 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
 405 #endif
 406         max_mapnr = highend_pfn;
 407 #else
 408         max_mapnr = max_low_pfn;
 409 #endif
 410         high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
 411
 412         totalram_pages += free_all_bootmem();
 413         totalram_pages -= setup_zero_pages();   /* Setup zeroed pages.  */
 414
 415         reservedpages = ram = 0;
 416         for (tmp = 0; tmp < max_low_pfn; tmp++)
 417                 if (page_is_ram(tmp)) {
 418                         ram++;
 419                         if (PageReserved(pfn_to_page(tmp)))
 420                                 reservedpages++;
 421                 }
 422         num_physpages = ram;
 423
 424 #ifdef CONFIG_HIGHMEM
 425         for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
 426                 struct page *page = mem_map + tmp;
 427
 428                 if (!page_is_ram(tmp)) {
 429                         SetPageReserved(page);
 430                         continue;
 431                 }
 432                 ClearPageReserved(page);
 433 #ifdef CONFIG_LIMITED_DMA
 434                 set_page_address(page, lowmem_page_address(page));
 435 #endif
 436                 init_page_count(page);
 437                 __free_page(page);
 438                 totalhigh_pages++;
 439         }
 440         totalram_pages += totalhigh_pages;
 441         num_physpages += totalhigh_pages;
 442 #endif
 443
 444         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 445         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 446         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 447
 448 #ifdef CONFIG_64BIT
 449         if ((unsigned long) &_text > (unsigned long) CKSEG0)
 450                 /* The -4 is a hack so that user tools don't have to handle
 451                    the overflow.  */
 452                 kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4);
 453 #endif
 454         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 455         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 456                    VMALLOC_END-VMALLOC_START);
 457
 458         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 459                "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
 460                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 461                ram << (PAGE_SHIFT-10),
 462                codesize >> 10,
 463                reservedpages << (PAGE_SHIFT-10),
 464                datasize >> 10,
 465                initsize >> 10,
 466                (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 467 }
 468 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 469
 470 static void free_init_pages(char *what, unsigned long begin, unsigned long end)
 471 {
 472         unsigned long pfn;
 473
 474         for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
 475                 struct page *page = pfn_to_page(pfn);
 476                 void *addr = phys_to_virt(PFN_PHYS(pfn));
 477
 478                 ClearPageReserved(page);
 479                 init_page_count(page);
 480                 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
 481                 __free_page(page);
 482                 totalram_pages++;
 483         }
 484         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 485 }
 486
 487 #ifdef CONFIG_BLK_DEV_INITRD
 488 void free_initrd_mem(unsigned long start, unsigned long end)
 489 {
 490         free_init_pages("initrd memory",
 491                         virt_to_phys((void *)start),
 492                         virt_to_phys((void *)end));
 493 }
 494 #endif
 495
 496 extern unsigned long prom_free_prom_memory(void);
 497
 498 void free_initmem(void)
 499 {
 500         unsigned long freed;
 501
 502         freed = prom_free_prom_memory();
 503         if (freed)
 504                 printk(KERN_INFO "Freeing firmware memory: %ldk freed\n",freed);
 505
 506         free_init_pages("unused kernel memory",
 507                         __pa_symbol(&__init_begin),
 508                         __pa_symbol(&__init_end));
 509 }