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 #include <linux/of_fdt.h> 29 30 #include <asm/bootparam.h> 31 #include <asm/page.h> 32 #include <asm/sections.h> 33 #include <asm/sysmem.h> 34 35 /* 36 * Initialize the bootmem system and give it all low memory we have available. 37 */ 38 39 void __init bootmem_init(void) 40 { 41 /* Reserve all memory below PHYS_OFFSET, as memory 42 * accounting doesn't work for pages below that address. 43 * 44 * If PHYS_OFFSET is zero reserve page at address 0: 45 * successfull allocations should never return NULL. 46 */ 47 if (PHYS_OFFSET) 48 memblock_reserve(0, PHYS_OFFSET); 49 else 50 memblock_reserve(0, 1); 51 52 early_init_fdt_scan_reserved_mem(); 53 54 if (!memblock_phys_mem_size()) 55 panic("No memory found!\n"); 56 57 min_low_pfn = PFN_UP(memblock_start_of_DRAM()); 58 min_low_pfn = max(min_low_pfn, PFN_UP(PHYS_OFFSET)); 59 max_pfn = PFN_DOWN(memblock_end_of_DRAM()); 60 max_low_pfn = min(max_pfn, MAX_LOW_PFN); 61 62 memblock_set_current_limit(PFN_PHYS(max_low_pfn)); 63 64 memblock_dump_all(); 65 } 66 67 68 void __init zones_init(void) 69 { 70 /* All pages are DMA-able, so we put them all in the DMA zone. */ 71 unsigned long zones_size[MAX_NR_ZONES] = { 72 [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET, 73 #ifdef CONFIG_HIGHMEM 74 [ZONE_HIGHMEM] = max_pfn - max_low_pfn, 75 #endif 76 }; 77 free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); 78 } 79 80 /* 81 * Initialize memory pages. 82 */ 83 84 void __init mem_init(void) 85 { 86 #ifdef CONFIG_HIGHMEM 87 unsigned long tmp; 88 89 reset_all_zones_managed_pages(); 90 for (tmp = max_low_pfn; tmp < max_pfn; tmp++) 91 free_highmem_page(pfn_to_page(tmp)); 92 #endif 93 94 max_mapnr = max_pfn - ARCH_PFN_OFFSET; 95 high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT); 96 97 free_all_bootmem(); 98 99 mem_init_print_info(NULL); 100 pr_info("virtual kernel memory layout:\n" 101 #ifdef CONFIG_HIGHMEM 102 " pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n" 103 " fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n" 104 #endif 105 #ifdef CONFIG_MMU 106 " vmalloc : 0x%08lx - 0x%08lx (%5lu MB)\n" 107 #endif 108 " lowmem : 0x%08lx - 0x%08lx (%5lu MB)\n", 109 #ifdef CONFIG_HIGHMEM 110 PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE, 111 (LAST_PKMAP*PAGE_SIZE) >> 10, 112 FIXADDR_START, FIXADDR_TOP, 113 (FIXADDR_TOP - FIXADDR_START) >> 10, 114 #endif 115 #ifdef CONFIG_MMU 116 VMALLOC_START, VMALLOC_END, 117 (VMALLOC_END - VMALLOC_START) >> 20, 118 PAGE_OFFSET, PAGE_OFFSET + 119 (max_low_pfn - min_low_pfn) * PAGE_SIZE, 120 #else 121 min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE, 122 #endif 123 ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20); 124 } 125 126 #ifdef CONFIG_BLK_DEV_INITRD 127 extern int initrd_is_mapped; 128 129 void free_initrd_mem(unsigned long start, unsigned long end) 130 { 131 if (initrd_is_mapped) 132 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 133 } 134 #endif 135 136 void free_initmem(void) 137 { 138 free_initmem_default(-1); 139 } 140 141 static void __init parse_memmap_one(char *p) 142 { 143 char *oldp; 144 unsigned long start_at, mem_size; 145 146 if (!p) 147 return; 148 149 oldp = p; 150 mem_size = memparse(p, &p); 151 if (p == oldp) 152 return; 153 154 switch (*p) { 155 case '@': 156 start_at = memparse(p + 1, &p); 157 memblock_add(start_at, mem_size); 158 break; 159 160 case '$': 161 start_at = memparse(p + 1, &p); 162 memblock_reserve(start_at, mem_size); 163 break; 164 165 case 0: 166 memblock_reserve(mem_size, -mem_size); 167 break; 168 169 default: 170 pr_warn("Unrecognized memmap syntax: %s\n", p); 171 break; 172 } 173 } 174 175 static int __init parse_memmap_opt(char *str) 176 { 177 while (str) { 178 char *k = strchr(str, ','); 179 180 if (k) 181 *k++ = 0; 182 183 parse_memmap_one(str); 184 str = k; 185 } 186 187 return 0; 188 } 189 early_param("memmap", parse_memmap_opt); 190