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