arch/mips/mm/init.c

   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/mmu_context.h>
  34 #include <asm/sections.h>
  35 #include <asm/pgtable.h>
  36 #include <asm/pgalloc.h>
  37 #include <asm/tlb.h>
  38
  39 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  40
  41 unsigned long highstart_pfn, highend_pfn;
  42
  43 /*
  44  * We have up to 8 empty zeroed pages so we can map one of the right colour
  45  * when needed.  This is necessary only on R4000 / R4400 SC and MC versions
  46  * where we have to avoid VCED / VECI exceptions for good performance at
  47  * any price.  Since page is never written to after the initialization we
  48  * don't have to care about aliases on other CPUs.
  49  */
  50 unsigned long empty_zero_page, zero_page_mask;
  51
  52 /*
  53  * Not static inline because used by IP27 special magic initialization code
  54  */
  55 unsigned long setup_zero_pages(void)
  56 {
  57         unsigned int order;
  58         unsigned long size;
  59         struct page *page;
  60
  61         if (cpu_has_vce)
  62                 order = 3;
  63         else
  64                 order = 0;
  65
  66         empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
  67         if (!empty_zero_page)
  68                 panic("Oh boy, that early out of memory?");
  69
  70         page = virt_to_page(empty_zero_page);
  71         split_page(page, order);
  72         while (page < virt_to_page(empty_zero_page + (PAGE_SIZE << order))) {
  73                 SetPageReserved(page);
  74                 page++;
  75         }
  76
  77         size = PAGE_SIZE << order;
  78         zero_page_mask = (size - 1) & PAGE_MASK;
  79
  80         return 1UL << order;
  81 }
  82
  83 #ifdef CONFIG_HIGHMEM
  84 pte_t *kmap_pte;
  85 pgprot_t kmap_prot;
  86
  87 #define kmap_get_fixmap_pte(vaddr)                                      \
  88         pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))
  89
  90 static void __init kmap_init(void)
  91 {
  92         unsigned long kmap_vstart;
  93
  94         /* cache the first kmap pte */
  95         kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
  96         kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
  97
  98         kmap_prot = PAGE_KERNEL;
  99 }
 100
 101 #ifdef CONFIG_32BIT
 102 void __init fixrange_init(unsigned long start, unsigned long end,
 103         pgd_t *pgd_base)
 104 {
 105         pgd_t *pgd;
 106         pud_t *pud;
 107         pmd_t *pmd;
 108         pte_t *pte;
 109         int i, j, k;
 110         unsigned long vaddr;
 111
 112         vaddr = start;
 113         i = __pgd_offset(vaddr);
 114         j = __pud_offset(vaddr);
 115         k = __pmd_offset(vaddr);
 116         pgd = pgd_base + i;
 117
 118         for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
 119                 pud = (pud_t *)pgd;
 120                 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
 121                         pmd = (pmd_t *)pud;
 122                         for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
 123                                 if (pmd_none(*pmd)) {
 124                                         pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
 125                                         set_pmd(pmd, __pmd(pte));
 126                                         if (pte != pte_offset_kernel(pmd, 0))
 127                                                 BUG();
 128                                 }
 129                                 vaddr += PMD_SIZE;
 130                         }
 131                         k = 0;
 132                 }
 133                 j = 0;
 134         }
 135 }
 136 #endif /* CONFIG_32BIT */
 137 #endif /* CONFIG_HIGHMEM */
 138
 139 #ifndef CONFIG_NEED_MULTIPLE_NODES
 140 extern void pagetable_init(void);
 141
 142 static int __init page_is_ram(unsigned long pagenr)
 143 {
 144         int i;
 145
 146         for (i = 0; i < boot_mem_map.nr_map; i++) {
 147                 unsigned long addr, end;
 148
 149                 if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
 150                         /* not usable memory */
 151                         continue;
 152
 153                 addr = PFN_UP(boot_mem_map.map[i].addr);
 154                 end = PFN_DOWN(boot_mem_map.map[i].addr +
 155                                boot_mem_map.map[i].size);
 156
 157                 if (pagenr >= addr && pagenr < end)
 158                         return 1;
 159         }
 160
 161         return 0;
 162 }
 163
 164 void __init paging_init(void)
 165 {
 166         unsigned long zones_size[] = { [0 ... MAX_NR_ZONES - 1] = 0 };
 167         unsigned long max_dma, high, low;
 168 #ifndef CONFIG_FLATMEM
 169         unsigned long zholes_size[] = { [0 ... MAX_NR_ZONES - 1] = 0 };
 170         unsigned long i, j, pfn;
 171 #endif
 172
 173         pagetable_init();
 174
 175 #ifdef CONFIG_HIGHMEM
 176         kmap_init();
 177 #endif
 178
 179         max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 180         low = max_low_pfn;
 181         high = highend_pfn;
 182
 183 #ifdef CONFIG_ISA
 184         if (low < max_dma)
 185                 zones_size[ZONE_DMA] = low;
 186         else {
 187                 zones_size[ZONE_DMA] = max_dma;
 188                 zones_size[ZONE_NORMAL] = low - max_dma;
 189         }
 190 #else
 191         zones_size[ZONE_DMA] = low;
 192 #endif
 193 #ifdef CONFIG_HIGHMEM
 194         if (cpu_has_dc_aliases) {
 195                 printk(KERN_WARNING "This processor doesn't support highmem.");
 196                 if (high - low)
 197                         printk(" %ldk highmem ignored", high - low);
 198                 printk("\n");
 199         } else
 200                 zones_size[ZONE_HIGHMEM] = high - low;
 201 #endif
 202
 203 #ifdef CONFIG_FLATMEM
 204         free_area_init(zones_size);
 205 #else
 206         pfn = 0;
 207         for (i = 0; i < MAX_NR_ZONES; i++)
 208                 for (j = 0; j < zones_size[i]; j++, pfn++)
 209                         if (!page_is_ram(pfn))
 210                                 zholes_size[i]++;
 211         free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size);
 212 #endif
 213 }
 214
 215 static struct kcore_list kcore_mem, kcore_vmalloc;
 216 #ifdef CONFIG_64BIT
 217 static struct kcore_list kcore_kseg0;
 218 #endif
 219
 220 void __init mem_init(void)
 221 {
 222         unsigned long codesize, reservedpages, datasize, initsize;
 223         unsigned long tmp, ram;
 224
 225 #ifdef CONFIG_HIGHMEM
 226 #ifdef CONFIG_DISCONTIGMEM
 227 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
 228 #endif
 229         max_mapnr = highend_pfn;
 230 #else
 231         max_mapnr = max_low_pfn;
 232 #endif
 233         high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
 234
 235         totalram_pages += free_all_bootmem();
 236         totalram_pages -= setup_zero_pages();   /* Setup zeroed pages.  */
 237
 238         reservedpages = ram = 0;
 239         for (tmp = 0; tmp < max_low_pfn; tmp++)
 240                 if (page_is_ram(tmp)) {
 241                         ram++;
 242                         if (PageReserved(pfn_to_page(tmp)))
 243                                 reservedpages++;
 244                 }
 245         num_physpages = ram;
 246
 247 #ifdef CONFIG_HIGHMEM
 248         for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
 249                 struct page *page = mem_map + tmp;
 250
 251                 if (!page_is_ram(tmp)) {
 252                         SetPageReserved(page);
 253                         continue;
 254                 }
 255                 ClearPageReserved(page);
 256 #ifdef CONFIG_LIMITED_DMA
 257                 set_page_address(page, lowmem_page_address(page));
 258 #endif
 259                 init_page_count(page);
 260                 __free_page(page);
 261                 totalhigh_pages++;
 262         }
 263         totalram_pages += totalhigh_pages;
 264         num_physpages += totalhigh_pages;
 265 #endif
 266
 267         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 268         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 269         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 270
 271 #ifdef CONFIG_64BIT
 272         if ((unsigned long) &_text > (unsigned long) CKSEG0)
 273                 /* The -4 is a hack so that user tools don't have to handle
 274                    the overflow.  */
 275                 kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4);
 276 #endif
 277         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 278         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 279                    VMALLOC_END-VMALLOC_START);
 280
 281         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 282                "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
 283                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 284                ram << (PAGE_SHIFT-10),
 285                codesize >> 10,
 286                reservedpages << (PAGE_SHIFT-10),
 287                datasize >> 10,
 288                initsize >> 10,
 289                (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 290 }
 291 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 292
 293 void free_init_pages(char *what, unsigned long begin, unsigned long end)
 294 {
 295         unsigned long addr;
 296
 297         for (addr = begin; addr < end; addr += PAGE_SIZE) {
 298                 ClearPageReserved(virt_to_page(addr));
 299                 init_page_count(virt_to_page(addr));
 300                 memset((void *)addr, 0xcc, PAGE_SIZE);
 301                 free_page(addr);
 302                 totalram_pages++;
 303         }
 304         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 305 }
 306
 307 #ifdef CONFIG_BLK_DEV_INITRD
 308 void free_initrd_mem(unsigned long start, unsigned long end)
 309 {
 310 #ifdef CONFIG_64BIT
 311         /* Switch from KSEG0 to XKPHYS addresses */
 312         start = (unsigned long)phys_to_virt(CPHYSADDR(start));
 313         end = (unsigned long)phys_to_virt(CPHYSADDR(end));
 314 #endif
 315         free_init_pages("initrd memory", start, end);
 316 }
 317 #endif
 318
 319 extern unsigned long prom_free_prom_memory(void);
 320
 321 void free_initmem(void)
 322 {
 323         unsigned long start, end, freed;
 324
 325         freed = prom_free_prom_memory();
 326         if (freed)
 327                 printk(KERN_INFO "Freeing firmware memory: %ldk freed\n",freed);
 328
 329         start = (unsigned long)(&__init_begin);
 330         end = (unsigned long)(&__init_end);
 331 #ifdef CONFIG_64BIT
 332         start = PAGE_OFFSET | CPHYSADDR(start);
 333         end = PAGE_OFFSET | CPHYSADDR(end);
 334 #endif
 335         free_init_pages("unused kernel memory", start, end);
 336 }