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/swap.h>
  19
  20 #include <asm/page.h>
  21 #include <asm/mmu_context.h>
  22 #include <asm/pgalloc.h>
  23 #include <asm/sections.h>
  24 #include <asm/tlb.h>
  25
  26 unsigned int __page_offset;
  27 /* EXPORT_SYMBOL(__page_offset); */
  28
  29 char *klimit = _end;
  30
  31 /*
  32  * Initialize the bootmem system and give it all the memory we
  33  * have available.
  34  */
  35 unsigned int memory_start;
  36 unsigned int memory_end; /* due to mm/nommu.c */
  37 unsigned int memory_size;
  38
  39 /*
  40  * paging_init() sets up the page tables - in fact we've already done this.
  41  */
  42 static void __init paging_init(void)
  43 {
  44         int i;
  45         unsigned long zones_size[MAX_NR_ZONES];
  46
  47         /*
  48          * old: we can DMA to/from any address.put all page into ZONE_DMA
  49          * We use only ZONE_NORMAL
  50          */
  51         zones_size[ZONE_NORMAL] = max_mapnr;
  52
  53         /* every other zones are empty */
  54         for (i = 1; i < MAX_NR_ZONES; i++)
  55                 zones_size[i] = 0;
  56
  57         free_area_init(zones_size);
  58 }
  59
  60 void __init setup_memory(void)
  61 {
  62         int i;
  63         unsigned long map_size;
  64         u32 kernel_align_start, kernel_align_size;
  65
  66         /* Find main memory where is the kernel */
  67         for (i = 0; i < lmb.memory.cnt; i++) {
  68                 memory_start = (u32) lmb.memory.region[i].base;
  69                 memory_end = (u32) lmb.memory.region[i].base
  70                                 + (u32) lmb.memory.region[i].size;
  71                 if ((memory_start <= (u32)_text) &&
  72                                         ((u32)_text <= memory_end)) {
  73                         memory_size = memory_end - memory_start;
  74                         PAGE_OFFSET = memory_start;
  75                         printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, "
  76                                 "size 0x%08x\n", __func__, memory_start,
  77                                                 memory_end, memory_size);
  78                         break;
  79                 }
  80         }
  81
  82         if (!memory_start || !memory_end) {
  83                 panic("%s: Missing memory setting 0x%08x-0x%08x\n",
  84                         __func__, memory_start, memory_end);
  85         }
  86
  87         /* reservation of region where is the kernel */
  88         kernel_align_start = PAGE_DOWN((u32)_text);
  89         /* ALIGN can be remove because _end in vmlinux.lds.S is align */
  90         kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
  91         lmb_reserve(kernel_align_start, kernel_align_size);
  92         printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n",
  93                 __func__, kernel_align_start, kernel_align_start
  94                         + kernel_align_size, kernel_align_size);
  95
  96         /*
  97          * Kernel:
  98          * start: base phys address of kernel - page align
  99          * end: base phys address of kernel - page align
 100          *
 101          * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
 102          * max_low_pfn
 103          * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
 104          * num_physpages - number of all pages
 105          */
 106
 107         /* memory start is from the kernel end (aligned) to higher addr */
 108         min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
 109         /* RAM is assumed contiguous */
 110         num_physpages = max_mapnr = memory_size >> PAGE_SHIFT;
 111         max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT;
 112
 113         printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr);
 114         printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
 115         printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
 116
 117         /*
 118          * Find an area to use for the bootmem bitmap.
 119          * We look for the first area which is at least
 120          * 128kB in length (128kB is enough for a bitmap
 121          * for 4GB of memory, using 4kB pages), plus 1 page
 122          * (in case the address isn't page-aligned).
 123          */
 124         map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)_end)),
 125                                         min_low_pfn, max_low_pfn);
 126
 127         lmb_reserve(PFN_UP(TOPHYS((u32)_end)) << PAGE_SHIFT, map_size);
 128
 129         /* free bootmem is whole main memory */
 130         free_bootmem(memory_start, memory_size);
 131
 132         /* reserve allocate blocks */
 133         for (i = 0; i < lmb.reserved.cnt; i++) {
 134                 pr_debug("reserved %d - 0x%08x-0x%08x\n", i,
 135                         (u32) lmb.reserved.region[i].base,
 136                         (u32) lmb_size_bytes(&lmb.reserved, i));
 137                 reserve_bootmem(lmb.reserved.region[i].base,
 138                         lmb_size_bytes(&lmb.reserved, i) - 1, BOOTMEM_DEFAULT);
 139         }
 140         paging_init();
 141 }
 142
 143 void free_init_pages(char *what, unsigned long begin, unsigned long end)
 144 {
 145         unsigned long addr;
 146
 147         for (addr = begin; addr < end; addr += PAGE_SIZE) {
 148                 ClearPageReserved(virt_to_page(addr));
 149                 init_page_count(virt_to_page(addr));
 150                 memset((void *)addr, 0xcc, PAGE_SIZE);
 151                 free_page(addr);
 152                 totalram_pages++;
 153         }
 154         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 155 }
 156
 157 #ifdef CONFIG_BLK_DEV_INITRD
 158 void free_initrd_mem(unsigned long start, unsigned long end)
 159 {
 160         int pages = 0;
 161         for (; start < end; start += PAGE_SIZE) {
 162                 ClearPageReserved(virt_to_page(start));
 163                 init_page_count(virt_to_page(start));
 164                 free_page(start);
 165                 totalram_pages++;
 166                 pages++;
 167         }
 168         printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", pages);
 169 }
 170 #endif
 171
 172 void free_initmem(void)
 173 {
 174         free_init_pages("unused kernel memory",
 175                         (unsigned long)(&__init_begin),
 176                         (unsigned long)(&__init_end));
 177 }
 178
 179 /* FIXME from arch/powerpc/mm/mem.c*/
 180 void show_mem(void)
 181 {
 182         printk(KERN_NOTICE "%s\n", __func__);
 183 }
 184
 185 void __init mem_init(void)
 186 {
 187         high_memory = (void *)__va(memory_end);
 188         /* this will put all memory onto the freelists */
 189         totalram_pages += free_all_bootmem();
 190
 191         printk(KERN_INFO "Memory: %luk/%luk available\n",
 192                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 193                num_physpages << (PAGE_SHIFT-10));
 194 }
 195
 196 /* Check against bounds of physical memory */
 197 int ___range_ok(unsigned long addr, unsigned long size)
 198 {
 199         return ((addr < memory_start) ||
 200                 ((addr + size) > memory_end));
 201 }