arch/sparc/mm/init.c

   1 /*
   2  *  linux/arch/sparc/mm/init.c
   3  *
   4  *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5  *  Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
   6  *  Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   7  *  Copyright (C) 2000 Anton Blanchard (anton@samba.org)
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/signal.h>
  12 #include <linux/sched.h>
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/string.h>
  16 #include <linux/types.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/mman.h>
  19 #include <linux/mm.h>
  20 #include <linux/swap.h>
  21 #include <linux/initrd.h>
  22 #include <linux/init.h>
  23 #include <linux/highmem.h>
  24 #include <linux/bootmem.h>
  25 #include <linux/pagemap.h>
  26
  27 #include <asm/system.h>
  28 #include <asm/vac-ops.h>
  29 #include <asm/page.h>
  30 #include <asm/pgtable.h>
  31 #include <asm/vaddrs.h>
  32 #include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
  33 #include <asm/tlb.h>
  34 #include <asm/prom.h>
  35
  36 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  37
  38 unsigned long *sparc_valid_addr_bitmap;
  39
  40 unsigned long phys_base;
  41 unsigned long pfn_base;
  42
  43 unsigned long page_kernel;
  44
  45 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
  46 unsigned long sparc_unmapped_base;
  47
  48 struct pgtable_cache_struct pgt_quicklists;
  49
  50 /* References to section boundaries */
  51 extern char __init_begin, __init_end, _start, _end, etext , edata;
  52
  53 /* Initial ramdisk setup */
  54 extern unsigned int sparc_ramdisk_image;
  55 extern unsigned int sparc_ramdisk_size;
  56
  57 unsigned long highstart_pfn, highend_pfn;
  58
  59 pte_t *kmap_pte;
  60 pgprot_t kmap_prot;
  61
  62 #define kmap_get_fixmap_pte(vaddr) \
  63         pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
  64
  65 void __init kmap_init(void)
  66 {
  67         /* cache the first kmap pte */
  68         kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
  69         kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
  70 }
  71
  72 void show_mem(void)
  73 {
  74         printk("Mem-info:\n");
  75         show_free_areas();
  76         printk("Free swap:       %6ldkB\n",
  77                nr_swap_pages << (PAGE_SHIFT-10));
  78         printk("%ld pages of RAM\n", totalram_pages);
  79         printk("%ld free pages\n", nr_free_pages());
  80 #if 0 /* undefined pgtable_cache_size, pgd_cache_size */
  81         printk("%ld pages in page table cache\n",pgtable_cache_size);
  82 #ifndef CONFIG_SMP
  83         if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
  84                 printk("%ld entries in page dir cache\n",pgd_cache_size);
  85 #endif
  86 #endif
  87 }
  88
  89 void __init sparc_context_init(int numctx)
  90 {
  91         int ctx;
  92
  93         ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
  94
  95         for(ctx = 0; ctx < numctx; ctx++) {
  96                 struct ctx_list *clist;
  97
  98                 clist = (ctx_list_pool + ctx);
  99                 clist->ctx_number = ctx;
 100                 clist->ctx_mm = NULL;
 101         }
 102         ctx_free.next = ctx_free.prev = &ctx_free;
 103         ctx_used.next = ctx_used.prev = &ctx_used;
 104         for(ctx = 0; ctx < numctx; ctx++)
 105                 add_to_free_ctxlist(ctx_list_pool + ctx);
 106 }
 107
 108 extern unsigned long cmdline_memory_size;
 109 unsigned long last_valid_pfn;
 110
 111 unsigned long calc_highpages(void)
 112 {
 113         int i;
 114         int nr = 0;
 115
 116         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 117                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 118                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 119
 120                 if (end_pfn <= max_low_pfn)
 121                         continue;
 122
 123                 if (start_pfn < max_low_pfn)
 124                         start_pfn = max_low_pfn;
 125
 126                 nr += end_pfn - start_pfn;
 127         }
 128
 129         return nr;
 130 }
 131
 132 static unsigned long calc_max_low_pfn(void)
 133 {
 134         int i;
 135         unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 136         unsigned long curr_pfn, last_pfn;
 137
 138         last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
 139         for (i = 1; sp_banks[i].num_bytes != 0; i++) {
 140                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 141
 142                 if (curr_pfn >= tmp) {
 143                         if (last_pfn < tmp)
 144                                 tmp = last_pfn;
 145                         break;
 146                 }
 147
 148                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 149         }
 150
 151         return tmp;
 152 }
 153
 154 unsigned long __init bootmem_init(unsigned long *pages_avail)
 155 {
 156         unsigned long bootmap_size, start_pfn;
 157         unsigned long end_of_phys_memory = 0UL;
 158         unsigned long bootmap_pfn, bytes_avail, size;
 159         int i;
 160
 161         bytes_avail = 0UL;
 162         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 163                 end_of_phys_memory = sp_banks[i].base_addr +
 164                         sp_banks[i].num_bytes;
 165                 bytes_avail += sp_banks[i].num_bytes;
 166                 if (cmdline_memory_size) {
 167                         if (bytes_avail > cmdline_memory_size) {
 168                                 unsigned long slack = bytes_avail - cmdline_memory_size;
 169
 170                                 bytes_avail -= slack;
 171                                 end_of_phys_memory -= slack;
 172
 173                                 sp_banks[i].num_bytes -= slack;
 174                                 if (sp_banks[i].num_bytes == 0) {
 175                                         sp_banks[i].base_addr = 0xdeadbeef;
 176                                 } else {
 177                                         sp_banks[i+1].num_bytes = 0;
 178                                         sp_banks[i+1].base_addr = 0xdeadbeef;
 179                                 }
 180                                 break;
 181                         }
 182                 }
 183         }
 184
 185         /* Start with page aligned address of last symbol in kernel
 186          * image.
 187          */
 188         start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
 189
 190         /* Now shift down to get the real physical page frame number. */
 191         start_pfn >>= PAGE_SHIFT;
 192
 193         bootmap_pfn = start_pfn;
 194
 195         max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 196
 197         max_low_pfn = max_pfn;
 198         highstart_pfn = highend_pfn = max_pfn;
 199
 200         if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 201                 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 202                 max_low_pfn = calc_max_low_pfn();
 203                 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 204                     calc_highpages() >> (20 - PAGE_SHIFT));
 205         }
 206
 207 #ifdef CONFIG_BLK_DEV_INITRD
 208         /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
 209         if (sparc_ramdisk_image) {
 210                 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 211                         sparc_ramdisk_image -= KERNBASE;
 212                 initrd_start = sparc_ramdisk_image + phys_base;
 213                 initrd_end = initrd_start + sparc_ramdisk_size;
 214                 if (initrd_end > end_of_phys_memory) {
 215                         printk(KERN_CRIT "initrd extends beyond end of memory "
 216                                          "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 217                                initrd_end, end_of_phys_memory);
 218                         initrd_start = 0;
 219                 }
 220                 if (initrd_start) {
 221                         if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
 222                             initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
 223                                 bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
 224                 }
 225         }
 226 #endif
 227         /* Initialize the boot-time allocator. */
 228         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
 229                                          max_low_pfn);
 230
 231         /* Now register the available physical memory with the
 232          * allocator.
 233          */
 234         *pages_avail = 0;
 235         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 236                 unsigned long curr_pfn, last_pfn;
 237
 238                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 239                 if (curr_pfn >= max_low_pfn)
 240                         break;
 241
 242                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 243                 if (last_pfn > max_low_pfn)
 244                         last_pfn = max_low_pfn;
 245
 246                 /*
 247                  * .. finally, did all the rounding and playing
 248                  * around just make the area go away?
 249                  */
 250                 if (last_pfn <= curr_pfn)
 251                         continue;
 252
 253                 size = (last_pfn - curr_pfn) << PAGE_SHIFT;
 254                 *pages_avail += last_pfn - curr_pfn;
 255
 256                 free_bootmem(sp_banks[i].base_addr, size);
 257         }
 258
 259 #ifdef CONFIG_BLK_DEV_INITRD
 260         if (initrd_start) {
 261                 /* Reserve the initrd image area. */
 262                 size = initrd_end - initrd_start;
 263                 reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
 264                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 265
 266                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
 267                 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
 268         }
 269 #endif
 270         /* Reserve the kernel text/data/bss. */
 271         size = (start_pfn << PAGE_SHIFT) - phys_base;
 272         reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
 273         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 274
 275         /* Reserve the bootmem map.   We do not account for it
 276          * in pages_avail because we will release that memory
 277          * in free_all_bootmem.
 278          */
 279         size = bootmap_size;
 280         reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
 281         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 282
 283         return max_pfn;
 284 }
 285
 286 /*
 287  * check_pgt_cache
 288  *
 289  * This is called at the end of unmapping of VMA (zap_page_range),
 290  * to rescan the page cache for architecture specific things,
 291  * presumably something like sun4/sun4c PMEGs. Most architectures
 292  * define check_pgt_cache empty.
 293  *
 294  * We simply copy the 2.4 implementation for now.
 295  */
 296 static int pgt_cache_water[2] = { 25, 50 };
 297
 298 void check_pgt_cache(void)
 299 {
 300         do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
 301 }
 302
 303 /*
 304  * paging_init() sets up the page tables: We call the MMU specific
 305  * init routine based upon the Sun model type on the Sparc.
 306  *
 307  */
 308 extern void sun4c_paging_init(void);
 309 extern void srmmu_paging_init(void);
 310 extern void device_scan(void);
 311
 312 pgprot_t PAGE_SHARED __read_mostly;
 313 EXPORT_SYMBOL(PAGE_SHARED);
 314
 315 void __init paging_init(void)
 316 {
 317         switch(sparc_cpu_model) {
 318         case sun4c:
 319         case sun4e:
 320         case sun4:
 321                 sun4c_paging_init();
 322                 sparc_unmapped_base = 0xe0000000;
 323                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
 324                 break;
 325         case sun4m:
 326         case sun4d:
 327                 srmmu_paging_init();
 328                 sparc_unmapped_base = 0x50000000;
 329                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
 330                 break;
 331         default:
 332                 prom_printf("paging_init: Cannot init paging on this Sparc\n");
 333                 prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
 334                 prom_printf("paging_init: Halting...\n");
 335                 prom_halt();
 336         };
 337
 338         /* Initialize the protection map with non-constant, MMU dependent values. */
 339         protection_map[0] = PAGE_NONE;
 340         protection_map[1] = PAGE_READONLY;
 341         protection_map[2] = PAGE_COPY;
 342         protection_map[3] = PAGE_COPY;
 343         protection_map[4] = PAGE_READONLY;
 344         protection_map[5] = PAGE_READONLY;
 345         protection_map[6] = PAGE_COPY;
 346         protection_map[7] = PAGE_COPY;
 347         protection_map[8] = PAGE_NONE;
 348         protection_map[9] = PAGE_READONLY;
 349         protection_map[10] = PAGE_SHARED;
 350         protection_map[11] = PAGE_SHARED;
 351         protection_map[12] = PAGE_READONLY;
 352         protection_map[13] = PAGE_READONLY;
 353         protection_map[14] = PAGE_SHARED;
 354         protection_map[15] = PAGE_SHARED;
 355         btfixup();
 356         prom_build_devicetree();
 357         device_scan();
 358 }
 359
 360 static void __init taint_real_pages(void)
 361 {
 362         int i;
 363
 364         for (i = 0; sp_banks[i].num_bytes; i++) {
 365                 unsigned long start, end;
 366
 367                 start = sp_banks[i].base_addr;
 368                 end = start + sp_banks[i].num_bytes;
 369
 370                 while (start < end) {
 371                         set_bit(start >> 20, sparc_valid_addr_bitmap);
 372                         start += PAGE_SIZE;
 373                 }
 374         }
 375 }
 376
 377 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
 378 {
 379         unsigned long tmp;
 380
 381 #ifdef CONFIG_DEBUG_HIGHMEM
 382         printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
 383 #endif
 384
 385         for (tmp = start_pfn; tmp < end_pfn; tmp++) {
 386                 struct page *page = pfn_to_page(tmp);
 387
 388                 ClearPageReserved(page);
 389                 init_page_count(page);
 390                 __free_page(page);
 391                 totalhigh_pages++;
 392         }
 393 }
 394
 395 void __init mem_init(void)
 396 {
 397         int codepages = 0;
 398         int datapages = 0;
 399         int initpages = 0;
 400         int reservedpages = 0;
 401         int i;
 402
 403         if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 404                 prom_printf("BUG: fixmap and pkmap areas overlap\n");
 405                 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
 406                        PKMAP_BASE,
 407                        (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 408                        FIXADDR_START);
 409                 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 410                 prom_halt();
 411         }
 412
 413
 414         /* Saves us work later. */
 415         memset((void *)&empty_zero_page, 0, PAGE_SIZE);
 416
 417         i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
 418         i += 1;
 419         sparc_valid_addr_bitmap = (unsigned long *)
 420                 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
 421
 422         if (sparc_valid_addr_bitmap == NULL) {
 423                 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
 424                 prom_halt();
 425         }
 426         memset(sparc_valid_addr_bitmap, 0, i << 2);
 427
 428         taint_real_pages();
 429
 430         max_mapnr = last_valid_pfn - pfn_base;
 431         high_memory = __va(max_low_pfn << PAGE_SHIFT);
 432
 433         totalram_pages = free_all_bootmem();
 434
 435         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 436                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 437                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 438
 439                 num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
 440
 441                 if (end_pfn <= highstart_pfn)
 442                         continue;
 443
 444                 if (start_pfn < highstart_pfn)
 445                         start_pfn = highstart_pfn;
 446
 447                 map_high_region(start_pfn, end_pfn);
 448         }
 449
 450         totalram_pages += totalhigh_pages;
 451
 452         codepages = (((unsigned long) &etext) - ((unsigned long)&_start));
 453         codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
 454         datapages = (((unsigned long) &edata) - ((unsigned long)&etext));
 455         datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
 456         initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
 457         initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
 458
 459         /* Ignore memory holes for the purpose of counting reserved pages */
 460         for (i=0; i < max_low_pfn; i++)
 461                 if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
 462                     && PageReserved(pfn_to_page(i)))
 463                         reservedpages++;
 464
 465         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
 466                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 467                num_physpages << (PAGE_SHIFT - 10),
 468                codepages << (PAGE_SHIFT-10),
 469                reservedpages << (PAGE_SHIFT - 10),
 470                datapages << (PAGE_SHIFT-10),
 471                initpages << (PAGE_SHIFT-10),
 472                totalhigh_pages << (PAGE_SHIFT-10));
 473 }
 474
 475 void free_initmem (void)
 476 {
 477         unsigned long addr;
 478
 479         addr = (unsigned long)(&__init_begin);
 480         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 481                 struct page *p;
 482
 483                 p = virt_to_page(addr);
 484
 485                 ClearPageReserved(p);
 486                 init_page_count(p);
 487                 __free_page(p);
 488                 totalram_pages++;
 489                 num_physpages++;
 490         }
 491         printk (KERN_INFO "Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10);
 492 }
 493
 494 #ifdef CONFIG_BLK_DEV_INITRD
 495 void free_initrd_mem(unsigned long start, unsigned long end)
 496 {
 497         if (start < end)
 498                 printk (KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 499         for (; start < end; start += PAGE_SIZE) {
 500                 struct page *p = virt_to_page(start);
 501
 502                 ClearPageReserved(p);
 503                 init_page_count(p);
 504                 __free_page(p);
 505                 num_physpages++;
 506         }
 507 }
 508 #endif
 509
 510 void sparc_flush_page_to_ram(struct page *page)
 511 {
 512         unsigned long vaddr = (unsigned long)page_address(page);
 513
 514         if (vaddr)
 515                 __flush_page_to_ram(vaddr);
 516 }