1 /* 2 * arch/xtensa/mm/init.c 3 * 4 * Derived from MIPS, PPC. 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file "COPYING" in the main directory of this archive 8 * for more details. 9 * 10 * Copyright (C) 2001 - 2005 Tensilica Inc. 11 * 12 * Chris Zankel <chris@zankel.net> 13 * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> 14 * Marc Gauthier 15 * Kevin Chea 16 */ 17 18 #include <linux/kernel.h> 19 #include <linux/errno.h> 20 #include <linux/bootmem.h> 21 #include <linux/gfp.h> 22 #include <linux/swap.h> 23 #include <linux/mman.h> 24 #include <linux/nodemask.h> 25 #include <linux/mm.h> 26 27 #include <asm/bootparam.h> 28 #include <asm/page.h> 29 #include <asm/sections.h> 30 31 /* 32 * mem_reserve(start, end, must_exist) 33 * 34 * Reserve some memory from the memory pool. 35 * 36 * Parameters: 37 * start Start of region, 38 * end End of region, 39 * must_exist Must exist in memory pool. 40 * 41 * Returns: 42 * 0 (memory area couldn't be mapped) 43 * -1 (success) 44 */ 45 46 int __init mem_reserve(unsigned long start, unsigned long end, int must_exist) 47 { 48 int i; 49 50 if (start == end) 51 return 0; 52 53 start = start & PAGE_MASK; 54 end = PAGE_ALIGN(end); 55 56 for (i = 0; i < sysmem.nr_banks; i++) 57 if (start < sysmem.bank[i].end 58 && end >= sysmem.bank[i].start) 59 break; 60 61 if (i == sysmem.nr_banks) { 62 if (must_exist) 63 printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) " 64 "not in any region!\n", start, end); 65 return 0; 66 } 67 68 if (start > sysmem.bank[i].start) { 69 if (end < sysmem.bank[i].end) { 70 /* split entry */ 71 if (sysmem.nr_banks >= SYSMEM_BANKS_MAX) 72 panic("meminfo overflow\n"); 73 sysmem.bank[sysmem.nr_banks].start = end; 74 sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end; 75 sysmem.nr_banks++; 76 } 77 sysmem.bank[i].end = start; 78 79 } else if (end < sysmem.bank[i].end) { 80 sysmem.bank[i].start = end; 81 82 } else { 83 /* remove entry */ 84 sysmem.nr_banks--; 85 sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start; 86 sysmem.bank[i].end = sysmem.bank[sysmem.nr_banks].end; 87 } 88 return -1; 89 } 90 91 92 /* 93 * Initialize the bootmem system and give it all the memory we have available. 94 */ 95 96 void __init bootmem_init(void) 97 { 98 unsigned long pfn; 99 unsigned long bootmap_start, bootmap_size; 100 int i; 101 102 max_low_pfn = max_pfn = 0; 103 min_low_pfn = ~0; 104 105 for (i=0; i < sysmem.nr_banks; i++) { 106 pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT; 107 if (pfn < min_low_pfn) 108 min_low_pfn = pfn; 109 pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT; 110 if (pfn > max_pfn) 111 max_pfn = pfn; 112 } 113 114 if (min_low_pfn > max_pfn) 115 panic("No memory found!\n"); 116 117 max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ? 118 max_pfn : MAX_MEM_PFN >> PAGE_SHIFT; 119 120 /* Find an area to use for the bootmem bitmap. */ 121 122 bootmap_size = bootmem_bootmap_pages(max_low_pfn - min_low_pfn); 123 bootmap_size <<= PAGE_SHIFT; 124 bootmap_start = ~0; 125 126 for (i=0; i<sysmem.nr_banks; i++) 127 if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) { 128 bootmap_start = sysmem.bank[i].start; 129 break; 130 } 131 132 if (bootmap_start == ~0UL) 133 panic("Cannot find %ld bytes for bootmap\n", bootmap_size); 134 135 /* Reserve the bootmem bitmap area */ 136 137 mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1); 138 bootmap_size = init_bootmem_node(NODE_DATA(0), 139 bootmap_start >> PAGE_SHIFT, 140 min_low_pfn, 141 max_low_pfn); 142 143 /* Add all remaining memory pieces into the bootmem map */ 144 145 for (i=0; i<sysmem.nr_banks; i++) 146 free_bootmem(sysmem.bank[i].start, 147 sysmem.bank[i].end - sysmem.bank[i].start); 148 149 } 150 151 152 void __init zones_init(void) 153 { 154 unsigned long zones_size[MAX_NR_ZONES]; 155 int i; 156 157 /* All pages are DMA-able, so we put them all in the DMA zone. */ 158 159 zones_size[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET; 160 for (i = 1; i < MAX_NR_ZONES; i++) 161 zones_size[i] = 0; 162 163 #ifdef CONFIG_HIGHMEM 164 zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn; 165 #endif 166 167 free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); 168 } 169 170 /* 171 * Initialize memory pages. 172 */ 173 174 void __init mem_init(void) 175 { 176 max_mapnr = max_low_pfn - ARCH_PFN_OFFSET; 177 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 178 179 #ifdef CONFIG_HIGHMEM 180 #error HIGHGMEM not implemented in init.c 181 #endif 182 183 free_all_bootmem(); 184 185 mem_init_print_info(NULL); 186 } 187 188 #ifdef CONFIG_BLK_DEV_INITRD 189 extern int initrd_is_mapped; 190 191 void free_initrd_mem(unsigned long start, unsigned long end) 192 { 193 if (initrd_is_mapped) 194 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 195 } 196 #endif 197 198 void free_initmem(void) 199 { 200 free_initmem_default(-1); 201 } 202