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 #include <asm/sysmem.h> 31 32 struct sysmem_info sysmem __initdata; 33 34 int __init add_sysmem_bank(unsigned long start, unsigned long end) 35 { 36 if (sysmem.nr_banks >= SYSMEM_BANKS_MAX) { 37 pr_warn("Ignoring memory bank 0x%08lx size %ldKB\n", 38 start, end - start); 39 return -EINVAL; 40 } 41 sysmem.bank[sysmem.nr_banks].start = PAGE_ALIGN(start); 42 sysmem.bank[sysmem.nr_banks].end = end & PAGE_MASK; 43 sysmem.nr_banks++; 44 45 return 0; 46 } 47 48 /* 49 * mem_reserve(start, end, must_exist) 50 * 51 * Reserve some memory from the memory pool. 52 * 53 * Parameters: 54 * start Start of region, 55 * end End of region, 56 * must_exist Must exist in memory pool. 57 * 58 * Returns: 59 * 0 (memory area couldn't be mapped) 60 * -1 (success) 61 */ 62 63 int __init mem_reserve(unsigned long start, unsigned long end, int must_exist) 64 { 65 int i; 66 67 if (start == end) 68 return 0; 69 70 start = start & PAGE_MASK; 71 end = PAGE_ALIGN(end); 72 73 for (i = 0; i < sysmem.nr_banks; i++) 74 if (start < sysmem.bank[i].end 75 && end >= sysmem.bank[i].start) 76 break; 77 78 if (i == sysmem.nr_banks) { 79 if (must_exist) 80 printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) " 81 "not in any region!\n", start, end); 82 return 0; 83 } 84 85 if (start > sysmem.bank[i].start) { 86 if (end < sysmem.bank[i].end) { 87 /* split entry */ 88 if (sysmem.nr_banks >= SYSMEM_BANKS_MAX) 89 panic("meminfo overflow\n"); 90 sysmem.bank[sysmem.nr_banks].start = end; 91 sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end; 92 sysmem.nr_banks++; 93 } 94 sysmem.bank[i].end = start; 95 96 } else if (end < sysmem.bank[i].end) { 97 sysmem.bank[i].start = end; 98 99 } else { 100 /* remove entry */ 101 sysmem.nr_banks--; 102 sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start; 103 sysmem.bank[i].end = sysmem.bank[sysmem.nr_banks].end; 104 } 105 return -1; 106 } 107 108 109 /* 110 * Initialize the bootmem system and give it all low memory we have available. 111 */ 112 113 void __init bootmem_init(void) 114 { 115 unsigned long pfn; 116 unsigned long bootmap_start, bootmap_size; 117 int i; 118 119 max_low_pfn = max_pfn = 0; 120 min_low_pfn = ~0; 121 122 for (i=0; i < sysmem.nr_banks; i++) { 123 pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT; 124 if (pfn < min_low_pfn) 125 min_low_pfn = pfn; 126 pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT; 127 if (pfn > max_pfn) 128 max_pfn = pfn; 129 } 130 131 if (min_low_pfn > max_pfn) 132 panic("No memory found!\n"); 133 134 max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ? 135 max_pfn : MAX_MEM_PFN >> PAGE_SHIFT; 136 137 /* Find an area to use for the bootmem bitmap. */ 138 139 bootmap_size = bootmem_bootmap_pages(max_low_pfn - min_low_pfn); 140 bootmap_size <<= PAGE_SHIFT; 141 bootmap_start = ~0; 142 143 for (i=0; i<sysmem.nr_banks; i++) 144 if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) { 145 bootmap_start = sysmem.bank[i].start; 146 break; 147 } 148 149 if (bootmap_start == ~0UL) 150 panic("Cannot find %ld bytes for bootmap\n", bootmap_size); 151 152 /* Reserve the bootmem bitmap area */ 153 154 mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1); 155 bootmap_size = init_bootmem_node(NODE_DATA(0), 156 bootmap_start >> PAGE_SHIFT, 157 min_low_pfn, 158 max_low_pfn); 159 160 /* Add all remaining memory pieces into the bootmem map */ 161 162 for (i = 0; i < sysmem.nr_banks; i++) { 163 if (sysmem.bank[i].start >> PAGE_SHIFT < max_low_pfn) { 164 unsigned long end = min(max_low_pfn << PAGE_SHIFT, 165 sysmem.bank[i].end); 166 free_bootmem(sysmem.bank[i].start, 167 end - sysmem.bank[i].start); 168 } 169 } 170 171 } 172 173 174 void __init zones_init(void) 175 { 176 unsigned long zones_size[MAX_NR_ZONES]; 177 int i; 178 179 /* All pages are DMA-able, so we put them all in the DMA zone. */ 180 181 zones_size[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET; 182 for (i = 1; i < MAX_NR_ZONES; i++) 183 zones_size[i] = 0; 184 185 #ifdef CONFIG_HIGHMEM 186 zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn; 187 #endif 188 189 free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); 190 } 191 192 /* 193 * Initialize memory pages. 194 */ 195 196 void __init mem_init(void) 197 { 198 max_mapnr = max_low_pfn - ARCH_PFN_OFFSET; 199 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 200 201 #ifdef CONFIG_HIGHMEM 202 #error HIGHGMEM not implemented in init.c 203 #endif 204 205 free_all_bootmem(); 206 207 mem_init_print_info(NULL); 208 } 209 210 #ifdef CONFIG_BLK_DEV_INITRD 211 extern int initrd_is_mapped; 212 213 void free_initrd_mem(unsigned long start, unsigned long end) 214 { 215 if (initrd_is_mapped) 216 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 217 } 218 #endif 219 220 void free_initmem(void) 221 { 222 free_initmem_default(-1); 223 } 224