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/swap.h> 17 #include <linux/module.h> 18 #include <linux/highmem.h> 19 #include <asm/page.h> 20 #include <asm/pgalloc.h> 21 #include <asm/sections.h> 22 #include <asm/arcregs.h> 23 24 pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE); 25 char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE); 26 EXPORT_SYMBOL(empty_zero_page); 27 28 static const unsigned long low_mem_start = CONFIG_LINUX_LINK_BASE; 29 static unsigned long low_mem_sz; 30 31 #ifdef CONFIG_HIGHMEM 32 static unsigned long min_high_pfn; 33 static u64 high_mem_start; 34 static u64 high_mem_sz; 35 #endif 36 37 /* User can over-ride above with "mem=nnn[KkMm]" in cmdline */ 38 static int __init setup_mem_sz(char *str) 39 { 40 low_mem_sz = memparse(str, NULL) & PAGE_MASK; 41 42 /* early console might not be setup yet - it will show up later */ 43 pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(low_mem_sz)); 44 45 return 0; 46 } 47 early_param("mem", setup_mem_sz); 48 49 void __init early_init_dt_add_memory_arch(u64 base, u64 size) 50 { 51 int in_use = 0; 52 53 if (!low_mem_sz) { 54 if (base != low_mem_start) 55 panic("CONFIG_LINUX_LINK_BASE != DT memory { }"); 56 57 low_mem_sz = size; 58 in_use = 1; 59 } else { 60 #ifdef CONFIG_HIGHMEM 61 high_mem_start = base; 62 high_mem_sz = size; 63 in_use = 1; 64 #endif 65 } 66 67 pr_info("Memory @ %llx [%lldM] %s\n", 68 base, TO_MB(size), !in_use ? "Not used":""); 69 } 70 71 #ifdef CONFIG_BLK_DEV_INITRD 72 static int __init early_initrd(char *p) 73 { 74 unsigned long start, size; 75 char *endp; 76 77 start = memparse(p, &endp); 78 if (*endp == ',') { 79 size = memparse(endp + 1, NULL); 80 81 initrd_start = (unsigned long)__va(start); 82 initrd_end = (unsigned long)__va(start + size); 83 } 84 return 0; 85 } 86 early_param("initrd", early_initrd); 87 #endif 88 89 /* 90 * First memory setup routine called from setup_arch() 91 * 1. setup swapper's mm @init_mm 92 * 2. Count the pages we have and setup bootmem allocator 93 * 3. zone setup 94 */ 95 void __init setup_arch_memory(void) 96 { 97 unsigned long zones_size[MAX_NR_ZONES]; 98 unsigned long zones_holes[MAX_NR_ZONES]; 99 100 init_mm.start_code = (unsigned long)_text; 101 init_mm.end_code = (unsigned long)_etext; 102 init_mm.end_data = (unsigned long)_edata; 103 init_mm.brk = (unsigned long)_end; 104 105 /* first page of system - kernel .vector starts here */ 106 min_low_pfn = ARCH_PFN_OFFSET; 107 108 /* Last usable page of low mem */ 109 max_low_pfn = max_pfn = PFN_DOWN(low_mem_start + low_mem_sz); 110 111 #ifdef CONFIG_HIGHMEM 112 min_high_pfn = PFN_DOWN(high_mem_start); 113 max_pfn = PFN_DOWN(high_mem_start + high_mem_sz); 114 #endif 115 116 max_mapnr = max_pfn - min_low_pfn; 117 118 /*------------- bootmem allocator setup -----------------------*/ 119 120 /* 121 * seed the bootmem allocator after any DT memory node parsing or 122 * "mem=xxx" cmdline overrides have potentially updated @arc_mem_sz 123 * 124 * Only low mem is added, otherwise we have crashes when allocating 125 * mem_map[] itself. NO_BOOTMEM allocates mem_map[] at the end of 126 * avail memory, ending in highmem with a > 32-bit address. However 127 * it then tries to memset it with a truncaed 32-bit handle, causing 128 * the crash 129 */ 130 131 memblock_add(low_mem_start, low_mem_sz); 132 memblock_reserve(low_mem_start, __pa(_end) - low_mem_start); 133 134 #ifdef CONFIG_BLK_DEV_INITRD 135 if (initrd_start) 136 memblock_reserve(__pa(initrd_start), initrd_end - initrd_start); 137 #endif 138 139 memblock_dump_all(); 140 141 /*----------------- node/zones setup --------------------------*/ 142 memset(zones_size, 0, sizeof(zones_size)); 143 memset(zones_holes, 0, sizeof(zones_holes)); 144 145 zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn; 146 zones_holes[ZONE_NORMAL] = 0; 147 148 #ifdef CONFIG_HIGHMEM 149 zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn; 150 151 /* This handles the peripheral address space hole */ 152 zones_holes[ZONE_HIGHMEM] = min_high_pfn - max_low_pfn; 153 #endif 154 155 /* 156 * We can't use the helper free_area_init(zones[]) because it uses 157 * PAGE_OFFSET to compute the @min_low_pfn which would be wrong 158 * when our kernel doesn't start at PAGE_OFFSET, i.e. 159 * PAGE_OFFSET != CONFIG_LINUX_LINK_BASE 160 */ 161 free_area_init_node(0, /* node-id */ 162 zones_size, /* num pages per zone */ 163 min_low_pfn, /* first pfn of node */ 164 zones_holes); /* holes */ 165 166 #ifdef CONFIG_HIGHMEM 167 high_memory = (void *)(min_high_pfn << PAGE_SHIFT); 168 kmap_init(); 169 #endif 170 } 171 172 /* 173 * mem_init - initializes memory 174 * 175 * Frees up bootmem 176 * Calculates and displays memory available/used 177 */ 178 void __init mem_init(void) 179 { 180 #ifdef CONFIG_HIGHMEM 181 unsigned long tmp; 182 183 reset_all_zones_managed_pages(); 184 for (tmp = min_high_pfn; tmp < max_pfn; tmp++) 185 free_highmem_page(pfn_to_page(tmp)); 186 #endif 187 188 free_all_bootmem(); 189 mem_init_print_info(NULL); 190 } 191 192 /* 193 * free_initmem: Free all the __init memory. 194 */ 195 void __init_refok free_initmem(void) 196 { 197 free_initmem_default(-1); 198 } 199 200 #ifdef CONFIG_BLK_DEV_INITRD 201 void __init free_initrd_mem(unsigned long start, unsigned long end) 202 { 203 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 204 } 205 #endif 206