1 /* 2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/mm.h> 11 #include <linux/bootmem.h> 12 #include <linux/memblock.h> 13 #ifdef CONFIG_BLK_DEV_INITRD 14 #include <linux/initrd.h> 15 #endif 16 #include <linux/of_fdt.h> 17 #include <linux/swap.h> 18 #include <linux/module.h> 19 #include <linux/highmem.h> 20 #include <asm/page.h> 21 #include <asm/pgalloc.h> 22 #include <asm/sections.h> 23 #include <asm/arcregs.h> 24 25 pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE); 26 char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE); 27 EXPORT_SYMBOL(empty_zero_page); 28 29 static const unsigned long low_mem_start = CONFIG_LINUX_LINK_BASE; 30 static unsigned long low_mem_sz; 31 32 #ifdef CONFIG_HIGHMEM 33 static unsigned long min_high_pfn, max_high_pfn; 34 static u64 high_mem_start; 35 static u64 high_mem_sz; 36 #endif 37 38 #ifdef CONFIG_DISCONTIGMEM 39 struct pglist_data node_data[MAX_NUMNODES] __read_mostly; 40 EXPORT_SYMBOL(node_data); 41 #endif 42 43 long __init arc_get_mem_sz(void) 44 { 45 return low_mem_sz; 46 } 47 48 /* User can over-ride above with "mem=nnn[KkMm]" in cmdline */ 49 static int __init setup_mem_sz(char *str) 50 { 51 low_mem_sz = memparse(str, NULL) & PAGE_MASK; 52 53 /* early console might not be setup yet - it will show up later */ 54 pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(low_mem_sz)); 55 56 return 0; 57 } 58 early_param("mem", setup_mem_sz); 59 60 void __init early_init_dt_add_memory_arch(u64 base, u64 size) 61 { 62 int in_use = 0; 63 64 if (!low_mem_sz) { 65 if (base != low_mem_start) 66 panic("CONFIG_LINUX_LINK_BASE != DT memory { }"); 67 68 low_mem_sz = size; 69 in_use = 1; 70 } else { 71 #ifdef CONFIG_HIGHMEM 72 high_mem_start = base; 73 high_mem_sz = size; 74 in_use = 1; 75 #endif 76 } 77 78 pr_info("Memory @ %llx [%lldM] %s\n", 79 base, TO_MB(size), !in_use ? "Not used":""); 80 } 81 82 #ifdef CONFIG_BLK_DEV_INITRD 83 static int __init early_initrd(char *p) 84 { 85 unsigned long start, size; 86 char *endp; 87 88 start = memparse(p, &endp); 89 if (*endp == ',') { 90 size = memparse(endp + 1, NULL); 91 92 initrd_start = (unsigned long)__va(start); 93 initrd_end = (unsigned long)__va(start + size); 94 } 95 return 0; 96 } 97 early_param("initrd", early_initrd); 98 #endif 99 100 /* 101 * First memory setup routine called from setup_arch() 102 * 1. setup swapper's mm @init_mm 103 * 2. Count the pages we have and setup bootmem allocator 104 * 3. zone setup 105 */ 106 void __init setup_arch_memory(void) 107 { 108 unsigned long zones_size[MAX_NR_ZONES]; 109 unsigned long zones_holes[MAX_NR_ZONES]; 110 111 init_mm.start_code = (unsigned long)_text; 112 init_mm.end_code = (unsigned long)_etext; 113 init_mm.end_data = (unsigned long)_edata; 114 init_mm.brk = (unsigned long)_end; 115 116 /* first page of system - kernel .vector starts here */ 117 min_low_pfn = ARCH_PFN_OFFSET; 118 119 /* Last usable page of low mem */ 120 max_low_pfn = max_pfn = PFN_DOWN(low_mem_start + low_mem_sz); 121 122 #ifdef CONFIG_FLATMEM 123 /* pfn_valid() uses this */ 124 max_mapnr = max_low_pfn - min_low_pfn; 125 #endif 126 127 /*------------- bootmem allocator setup -----------------------*/ 128 129 /* 130 * seed the bootmem allocator after any DT memory node parsing or 131 * "mem=xxx" cmdline overrides have potentially updated @arc_mem_sz 132 * 133 * Only low mem is added, otherwise we have crashes when allocating 134 * mem_map[] itself. NO_BOOTMEM allocates mem_map[] at the end of 135 * avail memory, ending in highmem with a > 32-bit address. However 136 * it then tries to memset it with a truncaed 32-bit handle, causing 137 * the crash 138 */ 139 140 memblock_add_node(low_mem_start, low_mem_sz, 0); 141 memblock_reserve(low_mem_start, __pa(_end) - low_mem_start); 142 143 #ifdef CONFIG_BLK_DEV_INITRD 144 if (initrd_start) 145 memblock_reserve(__pa(initrd_start), initrd_end - initrd_start); 146 #endif 147 148 early_init_fdt_reserve_self(); 149 early_init_fdt_scan_reserved_mem(); 150 151 memblock_dump_all(); 152 153 /*----------------- node/zones setup --------------------------*/ 154 memset(zones_size, 0, sizeof(zones_size)); 155 memset(zones_holes, 0, sizeof(zones_holes)); 156 157 zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn; 158 zones_holes[ZONE_NORMAL] = 0; 159 160 /* 161 * We can't use the helper free_area_init(zones[]) because it uses 162 * PAGE_OFFSET to compute the @min_low_pfn which would be wrong 163 * when our kernel doesn't start at PAGE_OFFSET, i.e. 164 * PAGE_OFFSET != CONFIG_LINUX_LINK_BASE 165 */ 166 free_area_init_node(0, /* node-id */ 167 zones_size, /* num pages per zone */ 168 min_low_pfn, /* first pfn of node */ 169 zones_holes); /* holes */ 170 171 #ifdef CONFIG_HIGHMEM 172 /* 173 * Populate a new node with highmem 174 * 175 * On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based) 176 * than addresses in normal ala low memory (0x8000_0000 based). 177 * Even with PAE, the huge peripheral space hole would waste a lot of 178 * mem with single mem_map[]. This warrants a mem_map per region design. 179 * Thus HIGHMEM on ARC is imlemented with DISCONTIGMEM. 180 * 181 * DISCONTIGMEM in turns requires multiple nodes. node 0 above is 182 * populated with normal memory zone while node 1 only has highmem 183 */ 184 node_set_online(1); 185 186 min_high_pfn = PFN_DOWN(high_mem_start); 187 max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz); 188 189 zones_size[ZONE_NORMAL] = 0; 190 zones_holes[ZONE_NORMAL] = 0; 191 192 zones_size[ZONE_HIGHMEM] = max_high_pfn - min_high_pfn; 193 zones_holes[ZONE_HIGHMEM] = 0; 194 195 free_area_init_node(1, /* node-id */ 196 zones_size, /* num pages per zone */ 197 min_high_pfn, /* first pfn of node */ 198 zones_holes); /* holes */ 199 200 high_memory = (void *)(min_high_pfn << PAGE_SHIFT); 201 kmap_init(); 202 #endif 203 } 204 205 /* 206 * mem_init - initializes memory 207 * 208 * Frees up bootmem 209 * Calculates and displays memory available/used 210 */ 211 void __init mem_init(void) 212 { 213 #ifdef CONFIG_HIGHMEM 214 unsigned long tmp; 215 216 reset_all_zones_managed_pages(); 217 for (tmp = min_high_pfn; tmp < max_high_pfn; tmp++) 218 free_highmem_page(pfn_to_page(tmp)); 219 #endif 220 221 free_all_bootmem(); 222 mem_init_print_info(NULL); 223 } 224 225 /* 226 * free_initmem: Free all the __init memory. 227 */ 228 void __ref free_initmem(void) 229 { 230 free_initmem_default(-1); 231 } 232 233 #ifdef CONFIG_BLK_DEV_INITRD 234 void __init free_initrd_mem(unsigned long start, unsigned long end) 235 { 236 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 237 } 238 #endif 239