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 * Copyright (C) 2014 - 2016 Cadence Design Systems Inc. 12 * 13 * Chris Zankel <chris@zankel.net> 14 * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> 15 * Marc Gauthier 16 * Kevin Chea 17 */ 18 19 #include <linux/kernel.h> 20 #include <linux/errno.h> 21 #include <linux/bootmem.h> 22 #include <linux/gfp.h> 23 #include <linux/highmem.h> 24 #include <linux/swap.h> 25 #include <linux/mman.h> 26 #include <linux/nodemask.h> 27 #include <linux/mm.h> 28 29 #include <asm/bootparam.h> 30 #include <asm/page.h> 31 #include <asm/sections.h> 32 #include <asm/sysmem.h> 33 34 /* 35 * Initialize the bootmem system and give it all low memory we have available. 36 */ 37 38 void __init bootmem_init(void) 39 { 40 /* Reserve all memory below PHYS_OFFSET, as memory 41 * accounting doesn't work for pages below that address. 42 * 43 * If PHYS_OFFSET is zero reserve page at address 0: 44 * successfull allocations should never return NULL. 45 */ 46 if (PHYS_OFFSET) 47 memblock_reserve(0, PHYS_OFFSET); 48 else 49 memblock_reserve(0, 1); 50 51 52 if (!memblock_phys_mem_size()) 53 panic("No memory found!\n"); 54 55 min_low_pfn = PFN_UP(memblock_start_of_DRAM()); 56 min_low_pfn = max(min_low_pfn, PFN_UP(PHYS_OFFSET)); 57 max_pfn = PFN_DOWN(memblock_end_of_DRAM()); 58 max_low_pfn = min(max_pfn, MAX_LOW_PFN); 59 60 memblock_set_current_limit(PFN_PHYS(max_low_pfn)); 61 62 memblock_dump_all(); 63 } 64 65 66 void __init zones_init(void) 67 { 68 /* All pages are DMA-able, so we put them all in the DMA zone. */ 69 unsigned long zones_size[MAX_NR_ZONES] = { 70 [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET, 71 #ifdef CONFIG_HIGHMEM 72 [ZONE_HIGHMEM] = max_pfn - max_low_pfn, 73 #endif 74 }; 75 free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); 76 } 77 78 /* 79 * Initialize memory pages. 80 */ 81 82 void __init mem_init(void) 83 { 84 #ifdef CONFIG_HIGHMEM 85 unsigned long tmp; 86 87 reset_all_zones_managed_pages(); 88 for (tmp = max_low_pfn; tmp < max_pfn; tmp++) 89 free_highmem_page(pfn_to_page(tmp)); 90 #endif 91 92 max_mapnr = max_pfn - ARCH_PFN_OFFSET; 93 high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT); 94 95 free_all_bootmem(); 96 97 mem_init_print_info(NULL); 98 pr_info("virtual kernel memory layout:\n" 99 #ifdef CONFIG_HIGHMEM 100 " pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n" 101 " fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n" 102 #endif 103 #ifdef CONFIG_MMU 104 " vmalloc : 0x%08lx - 0x%08lx (%5lu MB)\n" 105 #endif 106 " lowmem : 0x%08lx - 0x%08lx (%5lu MB)\n", 107 #ifdef CONFIG_HIGHMEM 108 PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE, 109 (LAST_PKMAP*PAGE_SIZE) >> 10, 110 FIXADDR_START, FIXADDR_TOP, 111 (FIXADDR_TOP - FIXADDR_START) >> 10, 112 #endif 113 #ifdef CONFIG_MMU 114 VMALLOC_START, VMALLOC_END, 115 (VMALLOC_END - VMALLOC_START) >> 20, 116 PAGE_OFFSET, PAGE_OFFSET + 117 (max_low_pfn - min_low_pfn) * PAGE_SIZE, 118 #else 119 min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE, 120 #endif 121 ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20); 122 } 123 124 #ifdef CONFIG_BLK_DEV_INITRD 125 extern int initrd_is_mapped; 126 127 void free_initrd_mem(unsigned long start, unsigned long end) 128 { 129 if (initrd_is_mapped) 130 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 131 } 132 #endif 133 134 void free_initmem(void) 135 { 136 free_initmem_default(-1); 137 } 138 139 static void __init parse_memmap_one(char *p) 140 { 141 char *oldp; 142 unsigned long start_at, mem_size; 143 144 if (!p) 145 return; 146 147 oldp = p; 148 mem_size = memparse(p, &p); 149 if (p == oldp) 150 return; 151 152 switch (*p) { 153 case '@': 154 start_at = memparse(p + 1, &p); 155 memblock_add(start_at, mem_size); 156 break; 157 158 case '$': 159 start_at = memparse(p + 1, &p); 160 memblock_reserve(start_at, mem_size); 161 break; 162 163 case 0: 164 memblock_reserve(mem_size, -mem_size); 165 break; 166 167 default: 168 pr_warn("Unrecognized memmap syntax: %s\n", p); 169 break; 170 } 171 } 172 173 static int __init parse_memmap_opt(char *str) 174 { 175 while (str) { 176 char *k = strchr(str, ','); 177 178 if (k) 179 *k++ = 0; 180 181 parse_memmap_one(str); 182 str = k; 183 } 184 185 return 0; 186 } 187 early_param("memmap", parse_memmap_opt); 188