arch/xtensa/mm/init.c

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