arch/microblaze/mm/init.c

   1 /*
   2  * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
   3  * Copyright (C) 2006 Atmark Techno, Inc.
   4  *
   5  * This file is subject to the terms and conditions of the GNU General Public
   6  * License. See the file "COPYING" in the main directory of this archive
   7  * for more details.
   8  */
   9
  10 #include <linux/bootmem.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/memblock.h>
  14 #include <linux/mm.h> /* mem_init */
  15 #include <linux/initrd.h>
  16 #include <linux/pagemap.h>
  17 #include <linux/pfn.h>
  18 #include <linux/slab.h>
  19 #include <linux/swap.h>
  20 #include <linux/export.h>
  21
  22 #include <asm/page.h>
  23 #include <asm/mmu_context.h>
  24 #include <asm/pgalloc.h>
  25 #include <asm/sections.h>
  26 #include <asm/tlb.h>
  27
  28 /* Use for MMU and noMMU because of PCI generic code */
  29 int mem_init_done;
  30
  31 #ifndef CONFIG_MMU
  32 unsigned int __page_offset;
  33 EXPORT_SYMBOL(__page_offset);
  34
  35 #else
  36 static int init_bootmem_done;
  37 #endif /* CONFIG_MMU */
  38
  39 char *klimit = _end;
  40
  41 /*
  42  * Initialize the bootmem system and give it all the memory we
  43  * have available.
  44  */
  45 unsigned long memory_start;
  46 EXPORT_SYMBOL(memory_start);
  47 unsigned long memory_end; /* due to mm/nommu.c */
  48 unsigned long memory_size;
  49 EXPORT_SYMBOL(memory_size);
  50
  51 /*
  52  * paging_init() sets up the page tables - in fact we've already done this.
  53  */
  54 static void __init paging_init(void)
  55 {
  56         unsigned long zones_size[MAX_NR_ZONES];
  57
  58         /* Clean every zones */
  59         memset(zones_size, 0, sizeof(zones_size));
  60
  61         /*
  62          * old: we can DMA to/from any address.put all page into ZONE_DMA
  63          * We use only ZONE_NORMAL
  64          */
  65         zones_size[ZONE_NORMAL] = max_mapnr;
  66
  67         free_area_init(zones_size);
  68 }
  69
  70 void __init setup_memory(void)
  71 {
  72         unsigned long map_size;
  73         struct memblock_region *reg;
  74
  75 #ifndef CONFIG_MMU
  76         u32 kernel_align_start, kernel_align_size;
  77
  78         /* Find main memory where is the kernel */
  79         for_each_memblock(memory, reg) {
  80                 memory_start = (u32)reg->base;
  81                 memory_end = (u32) reg->base + reg->size;
  82                 if ((memory_start <= (u32)_text) &&
  83                                         ((u32)_text <= memory_end)) {
  84                         memory_size = memory_end - memory_start;
  85                         PAGE_OFFSET = memory_start;
  86                         printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, "
  87                                 "size 0x%08x\n", __func__, (u32) memory_start,
  88                                         (u32) memory_end, (u32) memory_size);
  89                         break;
  90                 }
  91         }
  92
  93         if (!memory_start || !memory_end) {
  94                 panic("%s: Missing memory setting 0x%08x-0x%08x\n",
  95                         __func__, (u32) memory_start, (u32) memory_end);
  96         }
  97
  98         /* reservation of region where is the kernel */
  99         kernel_align_start = PAGE_DOWN((u32)_text);
 100         /* ALIGN can be remove because _end in vmlinux.lds.S is align */
 101         kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
 102         memblock_reserve(kernel_align_start, kernel_align_size);
 103         printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n",
 104                 __func__, kernel_align_start, kernel_align_start
 105                         + kernel_align_size, kernel_align_size);
 106
 107 #endif
 108         /*
 109          * Kernel:
 110          * start: base phys address of kernel - page align
 111          * end: base phys address of kernel - page align
 112          *
 113          * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
 114          * max_low_pfn
 115          * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
 116          * num_physpages - number of all pages
 117          */
 118
 119         /* memory start is from the kernel end (aligned) to higher addr */
 120         min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
 121         /* RAM is assumed contiguous */
 122         num_physpages = max_mapnr = memory_size >> PAGE_SHIFT;
 123         max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT;
 124
 125         printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr);
 126         printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
 127         printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
 128
 129         /*
 130          * Find an area to use for the bootmem bitmap.
 131          * We look for the first area which is at least
 132          * 128kB in length (128kB is enough for a bitmap
 133          * for 4GB of memory, using 4kB pages), plus 1 page
 134          * (in case the address isn't page-aligned).
 135          */
 136         map_size = init_bootmem_node(NODE_DATA(0),
 137                 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn);
 138         memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size);
 139
 140         /* free bootmem is whole main memory */
 141         free_bootmem(memory_start, memory_size);
 142
 143         /* reserve allocate blocks */
 144         for_each_memblock(reserved, reg) {
 145                 pr_debug("reserved - 0x%08x-0x%08x\n",
 146                          (u32) reg->base, (u32) reg->size);
 147                 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
 148         }
 149 #ifdef CONFIG_MMU
 150         init_bootmem_done = 1;
 151 #endif
 152         paging_init();
 153 }
 154
 155 void free_init_pages(char *what, unsigned long begin, unsigned long end)
 156 {
 157         unsigned long addr;
 158
 159         for (addr = begin; addr < end; addr += PAGE_SIZE) {
 160                 ClearPageReserved(virt_to_page(addr));
 161                 init_page_count(virt_to_page(addr));
 162                 free_page(addr);
 163                 totalram_pages++;
 164         }
 165         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 166 }
 167
 168 #ifdef CONFIG_BLK_DEV_INITRD
 169 void free_initrd_mem(unsigned long start, unsigned long end)
 170 {
 171         int pages = 0;
 172         for (; start < end; start += PAGE_SIZE) {
 173                 ClearPageReserved(virt_to_page(start));
 174                 init_page_count(virt_to_page(start));
 175                 free_page(start);
 176                 totalram_pages++;
 177                 pages++;
 178         }
 179         printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n",
 180                                         (int)(pages * (PAGE_SIZE / 1024)));
 181 }
 182 #endif
 183
 184 void free_initmem(void)
 185 {
 186         free_init_pages("unused kernel memory",
 187                         (unsigned long)(&__init_begin),
 188                         (unsigned long)(&__init_end));
 189 }
 190
 191 void __init mem_init(void)
 192 {
 193         high_memory = (void *)__va(memory_end);
 194         /* this will put all memory onto the freelists */
 195         totalram_pages += free_all_bootmem();
 196
 197         printk(KERN_INFO "Memory: %luk/%luk available\n",
 198                nr_free_pages() << (PAGE_SHIFT-10),
 199                num_physpages << (PAGE_SHIFT-10));
 200         mem_init_done = 1;
 201 }
 202
 203 #ifndef CONFIG_MMU
 204 int page_is_ram(unsigned long pfn)
 205 {
 206         return __range_ok(pfn, 0);
 207 }
 208 #else
 209 int page_is_ram(unsigned long pfn)
 210 {
 211         return pfn < max_low_pfn;
 212 }
 213
 214 /*
 215  * Check for command-line options that affect what MMU_init will do.
 216  */
 217 static void mm_cmdline_setup(void)
 218 {
 219         unsigned long maxmem = 0;
 220         char *p = cmd_line;
 221
 222         /* Look for mem= option on command line */
 223         p = strstr(cmd_line, "mem=");
 224         if (p) {
 225                 p += 4;
 226                 maxmem = memparse(p, &p);
 227                 if (maxmem && memory_size > maxmem) {
 228                         memory_size = maxmem;
 229                         memory_end = memory_start + memory_size;
 230                         memblock.memory.regions[0].size = memory_size;
 231                 }
 232         }
 233 }
 234
 235 /*
 236  * MMU_init_hw does the chip-specific initialization of the MMU hardware.
 237  */
 238 static void __init mmu_init_hw(void)
 239 {
 240         /*
 241          * The Zone Protection Register (ZPR) defines how protection will
 242          * be applied to every page which is a member of a given zone. At
 243          * present, we utilize only two of the zones.
 244          * The zone index bits (of ZSEL) in the PTE are used for software
 245          * indicators, except the LSB.  For user access, zone 1 is used,
 246          * for kernel access, zone 0 is used.  We set all but zone 1
 247          * to zero, allowing only kernel access as indicated in the PTE.
 248          * For zone 1, we set a 01 binary (a value of 10 will not work)
 249          * to allow user access as indicated in the PTE.  This also allows
 250          * kernel access as indicated in the PTE.
 251          */
 252         __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
 253                         "mts rzpr, r11;"
 254                         : : : "r11");
 255 }
 256
 257 /*
 258  * MMU_init sets up the basic memory mappings for the kernel,
 259  * including both RAM and possibly some I/O regions,
 260  * and sets up the page tables and the MMU hardware ready to go.
 261  */
 262
 263 /* called from head.S */
 264 asmlinkage void __init mmu_init(void)
 265 {
 266         unsigned int kstart, ksize;
 267
 268         if (!memblock.reserved.cnt) {
 269                 printk(KERN_EMERG "Error memory count\n");
 270                 machine_restart(NULL);
 271         }
 272
 273         if ((u32) memblock.memory.regions[0].size < 0x1000000) {
 274                 printk(KERN_EMERG "Memory must be greater than 16MB\n");
 275                 machine_restart(NULL);
 276         }
 277         /* Find main memory where the kernel is */
 278         memory_start = (u32) memblock.memory.regions[0].base;
 279         memory_end = (u32) memblock.memory.regions[0].base +
 280                                 (u32) memblock.memory.regions[0].size;
 281         memory_size = memory_end - memory_start;
 282
 283         mm_cmdline_setup(); /* FIXME parse args from command line - not used */
 284
 285         /*
 286          * Map out the kernel text/data/bss from the available physical
 287          * memory.
 288          */
 289         kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
 290         /* kernel size */
 291         ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
 292         memblock_reserve(kstart, ksize);
 293
 294 #if defined(CONFIG_BLK_DEV_INITRD)
 295         /* Remove the init RAM disk from the available memory. */
 296 /*      if (initrd_start) {
 297                 mem_pieces_remove(&phys_avail, __pa(initrd_start),
 298                                   initrd_end - initrd_start, 1);
 299         }*/
 300 #endif /* CONFIG_BLK_DEV_INITRD */
 301
 302         /* Initialize the MMU hardware */
 303         mmu_init_hw();
 304
 305         /* Map in all of RAM starting at CONFIG_KERNEL_START */
 306         mapin_ram();
 307
 308 #ifdef CONFIG_HIGHMEM_START_BOOL
 309         ioremap_base = CONFIG_HIGHMEM_START;
 310 #else
 311         ioremap_base = 0xfe000000UL;    /* for now, could be 0xfffff000 */
 312 #endif /* CONFIG_HIGHMEM_START_BOOL */
 313         ioremap_bot = ioremap_base;
 314
 315         /* Initialize the context management stuff */
 316         mmu_context_init();
 317 }
 318
 319 /* This is only called until mem_init is done. */
 320 void __init *early_get_page(void)
 321 {
 322         void *p;
 323         if (init_bootmem_done) {
 324                 p = alloc_bootmem_pages(PAGE_SIZE);
 325         } else {
 326                 /*
 327                  * Mem start + 32MB -> here is limit
 328                  * because of mem mapping from head.S
 329                  */
 330                 p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE,
 331                                         memory_start + 0x2000000));
 332         }
 333         return p;
 334 }
 335
 336 #endif /* CONFIG_MMU */
 337
 338 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask)
 339 {
 340         if (mem_init_done)
 341                 return kmalloc(size, mask);
 342         else
 343                 return alloc_bootmem(size);
 344 }
 345
 346 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask)
 347 {
 348         void *p;
 349
 350         if (mem_init_done)
 351                 p = kzalloc(size, mask);
 352         else {
 353                 p = alloc_bootmem(size);
 354                 if (p)
 355                         memset(p, 0, size);
 356         }
 357         return p;
 358 }