linux/arch/sparc/mm/init_32.c
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   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#include <linux/poison.h>
  27#include <linux/gfp.h>
  28
  29#include <asm/sections.h>
  30#include <asm/system.h>
  31#include <asm/vac-ops.h>
  32#include <asm/page.h>
  33#include <asm/pgtable.h>
  34#include <asm/vaddrs.h>
  35#include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
  36#include <asm/tlb.h>
  37#include <asm/prom.h>
  38#include <asm/leon.h>
  39
  40DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  41
  42unsigned long *sparc_valid_addr_bitmap;
  43EXPORT_SYMBOL(sparc_valid_addr_bitmap);
  44
  45unsigned long phys_base;
  46EXPORT_SYMBOL(phys_base);
  47
  48unsigned long pfn_base;
  49EXPORT_SYMBOL(pfn_base);
  50
  51unsigned long page_kernel;
  52EXPORT_SYMBOL(page_kernel);
  53
  54struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
  55unsigned long sparc_unmapped_base;
  56
  57struct pgtable_cache_struct pgt_quicklists;
  58
  59/* Initial ramdisk setup */
  60extern unsigned int sparc_ramdisk_image;
  61extern unsigned int sparc_ramdisk_size;
  62
  63unsigned long highstart_pfn, highend_pfn;
  64
  65pte_t *kmap_pte;
  66pgprot_t kmap_prot;
  67
  68#define kmap_get_fixmap_pte(vaddr) \
  69        pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
  70
  71void __init kmap_init(void)
  72{
  73        /* cache the first kmap pte */
  74        kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
  75        kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
  76}
  77
  78void show_mem(void)
  79{
  80        printk("Mem-info:\n");
  81        show_free_areas();
  82        printk("Free swap:       %6ldkB\n",
  83               nr_swap_pages << (PAGE_SHIFT-10));
  84        printk("%ld pages of RAM\n", totalram_pages);
  85        printk("%ld free pages\n", nr_free_pages());
  86#if 0 /* undefined pgtable_cache_size, pgd_cache_size */
  87        printk("%ld pages in page table cache\n",pgtable_cache_size);
  88#ifndef CONFIG_SMP
  89        if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
  90                printk("%ld entries in page dir cache\n",pgd_cache_size);
  91#endif  
  92#endif
  93}
  94
  95void __init sparc_context_init(int numctx)
  96{
  97        int ctx;
  98
  99        ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
 100
 101        for(ctx = 0; ctx < numctx; ctx++) {
 102                struct ctx_list *clist;
 103
 104                clist = (ctx_list_pool + ctx);
 105                clist->ctx_number = ctx;
 106                clist->ctx_mm = NULL;
 107        }
 108        ctx_free.next = ctx_free.prev = &ctx_free;
 109        ctx_used.next = ctx_used.prev = &ctx_used;
 110        for(ctx = 0; ctx < numctx; ctx++)
 111                add_to_free_ctxlist(ctx_list_pool + ctx);
 112}
 113
 114extern unsigned long cmdline_memory_size;
 115unsigned long last_valid_pfn;
 116
 117unsigned long calc_highpages(void)
 118{
 119        int i;
 120        int nr = 0;
 121
 122        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 123                unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 124                unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 125
 126                if (end_pfn <= max_low_pfn)
 127                        continue;
 128
 129                if (start_pfn < max_low_pfn)
 130                        start_pfn = max_low_pfn;
 131
 132                nr += end_pfn - start_pfn;
 133        }
 134
 135        return nr;
 136}
 137
 138static unsigned long calc_max_low_pfn(void)
 139{
 140        int i;
 141        unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 142        unsigned long curr_pfn, last_pfn;
 143
 144        last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
 145        for (i = 1; sp_banks[i].num_bytes != 0; i++) {
 146                curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 147
 148                if (curr_pfn >= tmp) {
 149                        if (last_pfn < tmp)
 150                                tmp = last_pfn;
 151                        break;
 152                }
 153
 154                last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 155        }
 156
 157        return tmp;
 158}
 159
 160unsigned long __init bootmem_init(unsigned long *pages_avail)
 161{
 162        unsigned long bootmap_size, start_pfn;
 163        unsigned long end_of_phys_memory = 0UL;
 164        unsigned long bootmap_pfn, bytes_avail, size;
 165        int i;
 166
 167        bytes_avail = 0UL;
 168        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 169                end_of_phys_memory = sp_banks[i].base_addr +
 170                        sp_banks[i].num_bytes;
 171                bytes_avail += sp_banks[i].num_bytes;
 172                if (cmdline_memory_size) {
 173                        if (bytes_avail > cmdline_memory_size) {
 174                                unsigned long slack = bytes_avail - cmdline_memory_size;
 175
 176                                bytes_avail -= slack;
 177                                end_of_phys_memory -= slack;
 178
 179                                sp_banks[i].num_bytes -= slack;
 180                                if (sp_banks[i].num_bytes == 0) {
 181                                        sp_banks[i].base_addr = 0xdeadbeef;
 182                                } else {
 183                                        sp_banks[i+1].num_bytes = 0;
 184                                        sp_banks[i+1].base_addr = 0xdeadbeef;
 185                                }
 186                                break;
 187                        }
 188                }
 189        }
 190
 191        /* Start with page aligned address of last symbol in kernel
 192         * image.  
 193         */
 194        start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
 195
 196        /* Now shift down to get the real physical page frame number. */
 197        start_pfn >>= PAGE_SHIFT;
 198
 199        bootmap_pfn = start_pfn;
 200
 201        max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 202
 203        max_low_pfn = max_pfn;
 204        highstart_pfn = highend_pfn = max_pfn;
 205
 206        if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 207                highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 208                max_low_pfn = calc_max_low_pfn();
 209                printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 210                    calc_highpages() >> (20 - PAGE_SHIFT));
 211        }
 212
 213#ifdef CONFIG_BLK_DEV_INITRD
 214        /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
 215        if (sparc_ramdisk_image) {
 216                if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 217                        sparc_ramdisk_image -= KERNBASE;
 218                initrd_start = sparc_ramdisk_image + phys_base;
 219                initrd_end = initrd_start + sparc_ramdisk_size;
 220                if (initrd_end > end_of_phys_memory) {
 221                        printk(KERN_CRIT "initrd extends beyond end of memory "
 222                                         "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 223                               initrd_end, end_of_phys_memory);
 224                        initrd_start = 0;
 225                }
 226                if (initrd_start) {
 227                        if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
 228                            initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
 229                                bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
 230                }
 231        }
 232#endif  
 233        /* Initialize the boot-time allocator. */
 234        bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
 235                                         max_low_pfn);
 236
 237        /* Now register the available physical memory with the
 238         * allocator.
 239         */
 240        *pages_avail = 0;
 241        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 242                unsigned long curr_pfn, last_pfn;
 243
 244                curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 245                if (curr_pfn >= max_low_pfn)
 246                        break;
 247
 248                last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 249                if (last_pfn > max_low_pfn)
 250                        last_pfn = max_low_pfn;
 251
 252                /*
 253                 * .. finally, did all the rounding and playing
 254                 * around just make the area go away?
 255                 */
 256                if (last_pfn <= curr_pfn)
 257                        continue;
 258
 259                size = (last_pfn - curr_pfn) << PAGE_SHIFT;
 260                *pages_avail += last_pfn - curr_pfn;
 261
 262                free_bootmem(sp_banks[i].base_addr, size);
 263        }
 264
 265#ifdef CONFIG_BLK_DEV_INITRD
 266        if (initrd_start) {
 267                /* Reserve the initrd image area. */
 268                size = initrd_end - initrd_start;
 269                reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
 270                *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 271
 272                initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
 273                initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;            
 274        }
 275#endif
 276        /* Reserve the kernel text/data/bss. */
 277        size = (start_pfn << PAGE_SHIFT) - phys_base;
 278        reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
 279        *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 280
 281        /* Reserve the bootmem map.   We do not account for it
 282         * in pages_avail because we will release that memory
 283         * in free_all_bootmem.
 284         */
 285        size = bootmap_size;
 286        reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
 287        *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 288
 289        return max_pfn;
 290}
 291
 292/*
 293 * check_pgt_cache
 294 *
 295 * This is called at the end of unmapping of VMA (zap_page_range),
 296 * to rescan the page cache for architecture specific things,
 297 * presumably something like sun4/sun4c PMEGs. Most architectures
 298 * define check_pgt_cache empty.
 299 *
 300 * We simply copy the 2.4 implementation for now.
 301 */
 302static int pgt_cache_water[2] = { 25, 50 };
 303
 304void check_pgt_cache(void)
 305{
 306        do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
 307}
 308
 309/*
 310 * paging_init() sets up the page tables: We call the MMU specific
 311 * init routine based upon the Sun model type on the Sparc.
 312 *
 313 */
 314extern void sun4c_paging_init(void);
 315extern void srmmu_paging_init(void);
 316extern void device_scan(void);
 317
 318pgprot_t PAGE_SHARED __read_mostly;
 319EXPORT_SYMBOL(PAGE_SHARED);
 320
 321void __init paging_init(void)
 322{
 323        switch(sparc_cpu_model) {
 324        case sun4c:
 325        case sun4e:
 326        case sun4:
 327                sun4c_paging_init();
 328                sparc_unmapped_base = 0xe0000000;
 329                BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
 330                break;
 331        case sparc_leon:
 332                leon_init();
 333                /* fall through */
 334        case sun4m:
 335        case sun4d:
 336                srmmu_paging_init();
 337                sparc_unmapped_base = 0x50000000;
 338                BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
 339                break;
 340        default:
 341                prom_printf("paging_init: Cannot init paging on this Sparc\n");
 342                prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
 343                prom_printf("paging_init: Halting...\n");
 344                prom_halt();
 345        };
 346
 347        /* Initialize the protection map with non-constant, MMU dependent values. */
 348        protection_map[0] = PAGE_NONE;
 349        protection_map[1] = PAGE_READONLY;
 350        protection_map[2] = PAGE_COPY;
 351        protection_map[3] = PAGE_COPY;
 352        protection_map[4] = PAGE_READONLY;
 353        protection_map[5] = PAGE_READONLY;
 354        protection_map[6] = PAGE_COPY;
 355        protection_map[7] = PAGE_COPY;
 356        protection_map[8] = PAGE_NONE;
 357        protection_map[9] = PAGE_READONLY;
 358        protection_map[10] = PAGE_SHARED;
 359        protection_map[11] = PAGE_SHARED;
 360        protection_map[12] = PAGE_READONLY;
 361        protection_map[13] = PAGE_READONLY;
 362        protection_map[14] = PAGE_SHARED;
 363        protection_map[15] = PAGE_SHARED;
 364        btfixup();
 365        prom_build_devicetree();
 366        of_fill_in_cpu_data();
 367        device_scan();
 368}
 369
 370static void __init taint_real_pages(void)
 371{
 372        int i;
 373
 374        for (i = 0; sp_banks[i].num_bytes; i++) {
 375                unsigned long start, end;
 376
 377                start = sp_banks[i].base_addr;
 378                end = start + sp_banks[i].num_bytes;
 379
 380                while (start < end) {
 381                        set_bit(start >> 20, sparc_valid_addr_bitmap);
 382                        start += PAGE_SIZE;
 383                }
 384        }
 385}
 386
 387static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
 388{
 389        unsigned long tmp;
 390
 391#ifdef CONFIG_DEBUG_HIGHMEM
 392        printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
 393#endif
 394
 395        for (tmp = start_pfn; tmp < end_pfn; tmp++) {
 396                struct page *page = pfn_to_page(tmp);
 397
 398                ClearPageReserved(page);
 399                init_page_count(page);
 400                __free_page(page);
 401                totalhigh_pages++;
 402        }
 403}
 404
 405void __init mem_init(void)
 406{
 407        int codepages = 0;
 408        int datapages = 0;
 409        int initpages = 0; 
 410        int reservedpages = 0;
 411        int i;
 412
 413        if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 414                prom_printf("BUG: fixmap and pkmap areas overlap\n");
 415                prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
 416                       PKMAP_BASE,
 417                       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 418                       FIXADDR_START);
 419                prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 420                prom_halt();
 421        }
 422
 423
 424        /* Saves us work later. */
 425        memset((void *)&empty_zero_page, 0, PAGE_SIZE);
 426
 427        i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
 428        i += 1;
 429        sparc_valid_addr_bitmap = (unsigned long *)
 430                __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
 431
 432        if (sparc_valid_addr_bitmap == NULL) {
 433                prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
 434                prom_halt();
 435        }
 436        memset(sparc_valid_addr_bitmap, 0, i << 2);
 437
 438        taint_real_pages();
 439
 440        max_mapnr = last_valid_pfn - pfn_base;
 441        high_memory = __va(max_low_pfn << PAGE_SHIFT);
 442
 443        totalram_pages = free_all_bootmem();
 444
 445        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 446                unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 447                unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 448
 449                num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
 450
 451                if (end_pfn <= highstart_pfn)
 452                        continue;
 453
 454                if (start_pfn < highstart_pfn)
 455                        start_pfn = highstart_pfn;
 456
 457                map_high_region(start_pfn, end_pfn);
 458        }
 459        
 460        totalram_pages += totalhigh_pages;
 461
 462        codepages = (((unsigned long) &_etext) - ((unsigned long)&_start));
 463        codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
 464        datapages = (((unsigned long) &_edata) - ((unsigned long)&_etext));
 465        datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
 466        initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
 467        initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
 468
 469        /* Ignore memory holes for the purpose of counting reserved pages */
 470        for (i=0; i < max_low_pfn; i++)
 471                if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
 472                    && PageReserved(pfn_to_page(i)))
 473                        reservedpages++;
 474
 475        printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
 476               nr_free_pages() << (PAGE_SHIFT-10),
 477               num_physpages << (PAGE_SHIFT - 10),
 478               codepages << (PAGE_SHIFT-10),
 479               reservedpages << (PAGE_SHIFT - 10),
 480               datapages << (PAGE_SHIFT-10), 
 481               initpages << (PAGE_SHIFT-10),
 482               totalhigh_pages << (PAGE_SHIFT-10));
 483}
 484
 485void free_initmem (void)
 486{
 487        unsigned long addr;
 488        unsigned long freed;
 489
 490        addr = (unsigned long)(&__init_begin);
 491        freed = (unsigned long)(&__init_end) - addr;
 492        for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 493                struct page *p;
 494
 495                memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
 496                p = virt_to_page(addr);
 497
 498                ClearPageReserved(p);
 499                init_page_count(p);
 500                __free_page(p);
 501                totalram_pages++;
 502                num_physpages++;
 503        }
 504        printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
 505                freed >> 10);
 506}
 507
 508#ifdef CONFIG_BLK_DEV_INITRD
 509void free_initrd_mem(unsigned long start, unsigned long end)
 510{
 511        if (start < end)
 512                printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
 513                        (end - start) >> 10);
 514        for (; start < end; start += PAGE_SIZE) {
 515                struct page *p;
 516
 517                memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
 518                p = virt_to_page(start);
 519
 520                ClearPageReserved(p);
 521                init_page_count(p);
 522                __free_page(p);
 523                totalram_pages++;
 524                num_physpages++;
 525        }
 526}
 527#endif
 528
 529void sparc_flush_page_to_ram(struct page *page)
 530{
 531        unsigned long vaddr = (unsigned long)page_address(page);
 532
 533        if (vaddr)
 534                __flush_page_to_ram(vaddr);
 535}
 536EXPORT_SYMBOL(sparc_flush_page_to_ram);
 537