arch/sparc/mm/init_32.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 #include <linux/poison.h>
  27 #include <linux/gfp.h>
  28
  29 #include <asm/sections.h>
  30 #include <asm/page.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/vaddrs.h>
  33 #include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
  34 #include <asm/setup.h>
  35 #include <asm/tlb.h>
  36 #include <asm/prom.h>
  37 #include <asm/leon.h>
  38
  39 #include "mm_32.h"
  40
  41 unsigned long *sparc_valid_addr_bitmap;
  42 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
  43
  44 unsigned long phys_base;
  45 EXPORT_SYMBOL(phys_base);
  46
  47 unsigned long pfn_base;
  48 EXPORT_SYMBOL(pfn_base);
  49
  50 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
  51
  52 /* Initial ramdisk setup */
  53 extern unsigned int sparc_ramdisk_image;
  54 extern unsigned int sparc_ramdisk_size;
  55
  56 unsigned long highstart_pfn, highend_pfn;
  57
  58 unsigned long last_valid_pfn;
  59
  60 unsigned long calc_highpages(void)
  61 {
  62         int i;
  63         int nr = 0;
  64
  65         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
  66                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
  67                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
  68
  69                 if (end_pfn <= max_low_pfn)
  70                         continue;
  71
  72                 if (start_pfn < max_low_pfn)
  73                         start_pfn = max_low_pfn;
  74
  75                 nr += end_pfn - start_pfn;
  76         }
  77
  78         return nr;
  79 }
  80
  81 static unsigned long calc_max_low_pfn(void)
  82 {
  83         int i;
  84         unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
  85         unsigned long curr_pfn, last_pfn;
  86
  87         last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
  88         for (i = 1; sp_banks[i].num_bytes != 0; i++) {
  89                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
  90
  91                 if (curr_pfn >= tmp) {
  92                         if (last_pfn < tmp)
  93                                 tmp = last_pfn;
  94                         break;
  95                 }
  96
  97                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
  98         }
  99
 100         return tmp;
 101 }
 102
 103 unsigned long __init bootmem_init(unsigned long *pages_avail)
 104 {
 105         unsigned long bootmap_size, start_pfn;
 106         unsigned long end_of_phys_memory = 0UL;
 107         unsigned long bootmap_pfn, bytes_avail, size;
 108         int i;
 109
 110         bytes_avail = 0UL;
 111         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 112                 end_of_phys_memory = sp_banks[i].base_addr +
 113                         sp_banks[i].num_bytes;
 114                 bytes_avail += sp_banks[i].num_bytes;
 115                 if (cmdline_memory_size) {
 116                         if (bytes_avail > cmdline_memory_size) {
 117                                 unsigned long slack = bytes_avail - cmdline_memory_size;
 118
 119                                 bytes_avail -= slack;
 120                                 end_of_phys_memory -= slack;
 121
 122                                 sp_banks[i].num_bytes -= slack;
 123                                 if (sp_banks[i].num_bytes == 0) {
 124                                         sp_banks[i].base_addr = 0xdeadbeef;
 125                                 } else {
 126                                         sp_banks[i+1].num_bytes = 0;
 127                                         sp_banks[i+1].base_addr = 0xdeadbeef;
 128                                 }
 129                                 break;
 130                         }
 131                 }
 132         }
 133
 134         /* Start with page aligned address of last symbol in kernel
 135          * image.
 136          */
 137         start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
 138
 139         /* Now shift down to get the real physical page frame number. */
 140         start_pfn >>= PAGE_SHIFT;
 141
 142         bootmap_pfn = start_pfn;
 143
 144         max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 145
 146         max_low_pfn = max_pfn;
 147         highstart_pfn = highend_pfn = max_pfn;
 148
 149         if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 150                 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 151                 max_low_pfn = calc_max_low_pfn();
 152                 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 153                     calc_highpages() >> (20 - PAGE_SHIFT));
 154         }
 155
 156 #ifdef CONFIG_BLK_DEV_INITRD
 157         /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
 158         if (sparc_ramdisk_image) {
 159                 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 160                         sparc_ramdisk_image -= KERNBASE;
 161                 initrd_start = sparc_ramdisk_image + phys_base;
 162                 initrd_end = initrd_start + sparc_ramdisk_size;
 163                 if (initrd_end > end_of_phys_memory) {
 164                         printk(KERN_CRIT "initrd extends beyond end of memory "
 165                                          "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 166                                initrd_end, end_of_phys_memory);
 167                         initrd_start = 0;
 168                 }
 169                 if (initrd_start) {
 170                         if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
 171                             initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
 172                                 bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
 173                 }
 174         }
 175 #endif
 176         /* Initialize the boot-time allocator. */
 177         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
 178                                          max_low_pfn);
 179
 180         /* Now register the available physical memory with the
 181          * allocator.
 182          */
 183         *pages_avail = 0;
 184         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 185                 unsigned long curr_pfn, last_pfn;
 186
 187                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 188                 if (curr_pfn >= max_low_pfn)
 189                         break;
 190
 191                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 192                 if (last_pfn > max_low_pfn)
 193                         last_pfn = max_low_pfn;
 194
 195                 /*
 196                  * .. finally, did all the rounding and playing
 197                  * around just make the area go away?
 198                  */
 199                 if (last_pfn <= curr_pfn)
 200                         continue;
 201
 202                 size = (last_pfn - curr_pfn) << PAGE_SHIFT;
 203                 *pages_avail += last_pfn - curr_pfn;
 204
 205                 free_bootmem(sp_banks[i].base_addr, size);
 206         }
 207
 208 #ifdef CONFIG_BLK_DEV_INITRD
 209         if (initrd_start) {
 210                 /* Reserve the initrd image area. */
 211                 size = initrd_end - initrd_start;
 212                 reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
 213                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 214
 215                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
 216                 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
 217         }
 218 #endif
 219         /* Reserve the kernel text/data/bss. */
 220         size = (start_pfn << PAGE_SHIFT) - phys_base;
 221         reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
 222         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 223
 224         /* Reserve the bootmem map.   We do not account for it
 225          * in pages_avail because we will release that memory
 226          * in free_all_bootmem.
 227          */
 228         size = bootmap_size;
 229         reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
 230         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 231
 232         return max_pfn;
 233 }
 234
 235 /*
 236  * paging_init() sets up the page tables: We call the MMU specific
 237  * init routine based upon the Sun model type on the Sparc.
 238  *
 239  */
 240 void __init paging_init(void)
 241 {
 242         srmmu_paging_init();
 243         prom_build_devicetree();
 244         of_fill_in_cpu_data();
 245         device_scan();
 246 }
 247
 248 static void __init taint_real_pages(void)
 249 {
 250         int i;
 251
 252         for (i = 0; sp_banks[i].num_bytes; i++) {
 253                 unsigned long start, end;
 254
 255                 start = sp_banks[i].base_addr;
 256                 end = start + sp_banks[i].num_bytes;
 257
 258                 while (start < end) {
 259                         set_bit(start >> 20, sparc_valid_addr_bitmap);
 260                         start += PAGE_SIZE;
 261                 }
 262         }
 263 }
 264
 265 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
 266 {
 267         unsigned long tmp;
 268
 269 #ifdef CONFIG_DEBUG_HIGHMEM
 270         printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
 271 #endif
 272
 273         for (tmp = start_pfn; tmp < end_pfn; tmp++)
 274                 free_highmem_page(pfn_to_page(tmp));
 275 }
 276
 277 void __init mem_init(void)
 278 {
 279         int i;
 280
 281         if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 282                 prom_printf("BUG: fixmap and pkmap areas overlap\n");
 283                 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
 284                        PKMAP_BASE,
 285                        (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 286                        FIXADDR_START);
 287                 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 288                 prom_halt();
 289         }
 290
 291
 292         /* Saves us work later. */
 293         memset((void *)empty_zero_page, 0, PAGE_SIZE);
 294
 295         i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
 296         i += 1;
 297         sparc_valid_addr_bitmap = (unsigned long *)
 298                 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
 299
 300         if (sparc_valid_addr_bitmap == NULL) {
 301                 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
 302                 prom_halt();
 303         }
 304         memset(sparc_valid_addr_bitmap, 0, i << 2);
 305
 306         taint_real_pages();
 307
 308         max_mapnr = last_valid_pfn - pfn_base;
 309         high_memory = __va(max_low_pfn << PAGE_SHIFT);
 310         free_all_bootmem();
 311
 312         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 313                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 314                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 315
 316                 if (end_pfn <= highstart_pfn)
 317                         continue;
 318
 319                 if (start_pfn < highstart_pfn)
 320                         start_pfn = highstart_pfn;
 321
 322                 map_high_region(start_pfn, end_pfn);
 323         }
 324
 325         mem_init_print_info(NULL);
 326 }
 327
 328 void free_initmem (void)
 329 {
 330         free_initmem_default(POISON_FREE_INITMEM);
 331 }
 332
 333 #ifdef CONFIG_BLK_DEV_INITRD
 334 void free_initrd_mem(unsigned long start, unsigned long end)
 335 {
 336         free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
 337                            "initrd");
 338 }
 339 #endif
 340
 341 void sparc_flush_page_to_ram(struct page *page)
 342 {
 343         unsigned long vaddr = (unsigned long)page_address(page);
 344
 345         if (vaddr)
 346                 __flush_page_to_ram(vaddr);
 347 }
 348 EXPORT_SYMBOL(sparc_flush_page_to_ram);