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/lmb.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 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  36
  37 static int init_bootmem_done;
  38 #endif /* CONFIG_MMU */
  39
  40 char *klimit = _end;
  41
  42 /*
  43  * Initialize the bootmem system and give it all the memory we
  44  * have available.
  45  */
  46 unsigned long memory_start;
  47 EXPORT_SYMBOL(memory_start);
  48 unsigned long memory_end; /* due to mm/nommu.c */
  49 unsigned long 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         int i;
  73         unsigned long map_size;
  74 #ifndef CONFIG_MMU
  75         u32 kernel_align_start, kernel_align_size;
  76
  77         /* Find main memory where is the kernel */
  78         for (i = 0; i < lmb.memory.cnt; i++) {
  79                 memory_start = (u32) lmb.memory.region[i].base;
  80                 memory_end = (u32) lmb.memory.region[i].base
  81                                 + (u32) lmb.memory.region[i].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         lmb_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 #ifndef CONFIG_MMU
 137         map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)klimit)),
 138                                         min_low_pfn, max_low_pfn);
 139 #else
 140         map_size = init_bootmem_node(&contig_page_data,
 141                 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn);
 142 #endif
 143         lmb_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size);
 144
 145         /* free bootmem is whole main memory */
 146         free_bootmem(memory_start, memory_size);
 147
 148         /* reserve allocate blocks */
 149         for (i = 0; i < lmb.reserved.cnt; i++) {
 150                 pr_debug("reserved %d - 0x%08x-0x%08x\n", i,
 151                         (u32) lmb.reserved.region[i].base,
 152                         (u32) lmb_size_bytes(&lmb.reserved, i));
 153                 reserve_bootmem(lmb.reserved.region[i].base,
 154                         lmb_size_bytes(&lmb.reserved, i) - 1, BOOTMEM_DEFAULT);
 155         }
 156 #ifdef CONFIG_MMU
 157         init_bootmem_done = 1;
 158 #endif
 159         paging_init();
 160 }
 161
 162 void free_init_pages(char *what, unsigned long begin, unsigned long end)
 163 {
 164         unsigned long addr;
 165
 166         for (addr = begin; addr < end; addr += PAGE_SIZE) {
 167                 ClearPageReserved(virt_to_page(addr));
 168                 init_page_count(virt_to_page(addr));
 169                 free_page(addr);
 170                 totalram_pages++;
 171         }
 172         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 173 }
 174
 175 #ifdef CONFIG_BLK_DEV_INITRD
 176 void free_initrd_mem(unsigned long start, unsigned long end)
 177 {
 178         int pages = 0;
 179         for (; start < end; start += PAGE_SIZE) {
 180                 ClearPageReserved(virt_to_page(start));
 181                 init_page_count(virt_to_page(start));
 182                 free_page(start);
 183                 totalram_pages++;
 184                 pages++;
 185         }
 186         printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n",
 187                                         (int)(pages * (PAGE_SIZE / 1024)));
 188 }
 189 #endif
 190
 191 void free_initmem(void)
 192 {
 193         free_init_pages("unused kernel memory",
 194                         (unsigned long)(&__init_begin),
 195                         (unsigned long)(&__init_end));
 196 }
 197
 198 void __init mem_init(void)
 199 {
 200         high_memory = (void *)__va(memory_end);
 201         /* this will put all memory onto the freelists */
 202         totalram_pages += free_all_bootmem();
 203
 204         printk(KERN_INFO "Memory: %luk/%luk available\n",
 205                nr_free_pages() << (PAGE_SHIFT-10),
 206                num_physpages << (PAGE_SHIFT-10));
 207         mem_init_done = 1;
 208 }
 209
 210 #ifndef CONFIG_MMU
 211 int page_is_ram(unsigned long pfn)
 212 {
 213         return __range_ok(pfn, 0);
 214 }
 215 #else
 216 int page_is_ram(unsigned long pfn)
 217 {
 218         return pfn < max_low_pfn;
 219 }
 220
 221 /*
 222  * Check for command-line options that affect what MMU_init will do.
 223  */
 224 static void mm_cmdline_setup(void)
 225 {
 226         unsigned long maxmem = 0;
 227         char *p = cmd_line;
 228
 229         /* Look for mem= option on command line */
 230         p = strstr(cmd_line, "mem=");
 231         if (p) {
 232                 p += 4;
 233                 maxmem = memparse(p, &p);
 234                 if (maxmem && memory_size > maxmem) {
 235                         memory_size = maxmem;
 236                         memory_end = memory_start + memory_size;
 237                         lmb.memory.region[0].size = memory_size;
 238                 }
 239         }
 240 }
 241
 242 /*
 243  * MMU_init_hw does the chip-specific initialization of the MMU hardware.
 244  */
 245 static void __init mmu_init_hw(void)
 246 {
 247         /*
 248          * The Zone Protection Register (ZPR) defines how protection will
 249          * be applied to every page which is a member of a given zone. At
 250          * present, we utilize only two of the zones.
 251          * The zone index bits (of ZSEL) in the PTE are used for software
 252          * indicators, except the LSB.  For user access, zone 1 is used,
 253          * for kernel access, zone 0 is used.  We set all but zone 1
 254          * to zero, allowing only kernel access as indicated in the PTE.
 255          * For zone 1, we set a 01 binary (a value of 10 will not work)
 256          * to allow user access as indicated in the PTE.  This also allows
 257          * kernel access as indicated in the PTE.
 258          */
 259         __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
 260                         "mts rzpr, r11;"
 261                         : : : "r11");
 262 }
 263
 264 /*
 265  * MMU_init sets up the basic memory mappings for the kernel,
 266  * including both RAM and possibly some I/O regions,
 267  * and sets up the page tables and the MMU hardware ready to go.
 268  */
 269
 270 /* called from head.S */
 271 asmlinkage void __init mmu_init(void)
 272 {
 273         unsigned int kstart, ksize;
 274
 275         if (!lmb.reserved.cnt) {
 276                 printk(KERN_EMERG "Error memory count\n");
 277                 machine_restart(NULL);
 278         }
 279
 280         if ((u32) lmb.memory.region[0].size < 0x1000000) {
 281                 printk(KERN_EMERG "Memory must be greater than 16MB\n");
 282                 machine_restart(NULL);
 283         }
 284         /* Find main memory where the kernel is */
 285         memory_start = (u32) lmb.memory.region[0].base;
 286         memory_end = (u32) lmb.memory.region[0].base +
 287                                 (u32) lmb.memory.region[0].size;
 288         memory_size = memory_end - memory_start;
 289
 290         mm_cmdline_setup(); /* FIXME parse args from command line - not used */
 291
 292         /*
 293          * Map out the kernel text/data/bss from the available physical
 294          * memory.
 295          */
 296         kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
 297         /* kernel size */
 298         ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
 299         lmb_reserve(kstart, ksize);
 300
 301 #if defined(CONFIG_BLK_DEV_INITRD)
 302         /* Remove the init RAM disk from the available memory. */
 303 /*      if (initrd_start) {
 304                 mem_pieces_remove(&phys_avail, __pa(initrd_start),
 305                                   initrd_end - initrd_start, 1);
 306         }*/
 307 #endif /* CONFIG_BLK_DEV_INITRD */
 308
 309         /* Initialize the MMU hardware */
 310         mmu_init_hw();
 311
 312         /* Map in all of RAM starting at CONFIG_KERNEL_START */
 313         mapin_ram();
 314
 315 #ifdef HIGHMEM_START_BOOL
 316         ioremap_base = HIGHMEM_START;
 317 #else
 318         ioremap_base = 0xfe000000UL;    /* for now, could be 0xfffff000 */
 319 #endif /* CONFIG_HIGHMEM */
 320         ioremap_bot = ioremap_base;
 321
 322         /* Initialize the context management stuff */
 323         mmu_context_init();
 324 }
 325
 326 /* This is only called until mem_init is done. */
 327 void __init *early_get_page(void)
 328 {
 329         void *p;
 330         if (init_bootmem_done) {
 331                 p = alloc_bootmem_pages(PAGE_SIZE);
 332         } else {
 333                 /*
 334                  * Mem start + 32MB -> here is limit
 335                  * because of mem mapping from head.S
 336                  */
 337                 p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE,
 338                                         memory_start + 0x2000000));
 339         }
 340         return p;
 341 }
 342
 343 #endif /* CONFIG_MMU */
 344
 345 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask)
 346 {
 347         if (mem_init_done)
 348                 return kmalloc(size, mask);
 349         else
 350                 return alloc_bootmem(size);
 351 }
 352
 353 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask)
 354 {
 355         void *p;
 356
 357         if (mem_init_done)
 358                 p = kzalloc(size, mask);
 359         else {
 360                 p = alloc_bootmem(size);
 361                 if (p)
 362                         memset(p, 0, size);
 363         }
 364         return p;
 365 }