arch/i386/kernel/std_resources.c

   1 /*
   2  *  Machine specific resource allocation for generic.
   3  */
   4
   5 #include <linux/ioport.h>
   6 #include <asm/io.h>
   7 #include <asm/std_resources.h>
   8
   9 #define romsignature(x) (*(unsigned short *)(x) == 0xaa55)
  10
  11 static struct resource system_rom_resource = {
  12         .name   = "System ROM",
  13         .start  = 0xf0000,
  14         .end    = 0xfffff,
  15         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  16 };
  17
  18 static struct resource extension_rom_resource = {
  19         .name   = "Extension ROM",
  20         .start  = 0xe0000,
  21         .end    = 0xeffff,
  22         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  23 };
  24
  25 static struct resource adapter_rom_resources[] = { {
  26         .name   = "Adapter ROM",
  27         .start  = 0xc8000,
  28         .end    = 0,
  29         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  30 }, {
  31         .name   = "Adapter ROM",
  32         .start  = 0,
  33         .end    = 0,
  34         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  35 }, {
  36         .name   = "Adapter ROM",
  37         .start  = 0,
  38         .end    = 0,
  39         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  40 }, {
  41         .name   = "Adapter ROM",
  42         .start  = 0,
  43         .end    = 0,
  44         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  45 }, {
  46         .name   = "Adapter ROM",
  47         .start  = 0,
  48         .end    = 0,
  49         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  50 }, {
  51         .name   = "Adapter ROM",
  52         .start  = 0,
  53         .end    = 0,
  54         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  55 } };
  56
  57 #define ADAPTER_ROM_RESOURCES \
  58         (sizeof adapter_rom_resources / sizeof adapter_rom_resources[0])
  59
  60 static struct resource video_rom_resource = {
  61         .name   = "Video ROM",
  62         .start  = 0xc0000,
  63         .end    = 0xc7fff,
  64         .flags  = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
  65 };
  66
  67 static struct resource vram_resource = {
  68         .name   = "Video RAM area",
  69         .start  = 0xa0000,
  70         .end    = 0xbffff,
  71         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
  72 };
  73
  74 static struct resource standard_io_resources[] = { {
  75         .name   = "dma1",
  76         .start  = 0x0000,
  77         .end    = 0x001f,
  78         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
  79 }, {
  80         .name   = "pic1",
  81         .start  = 0x0020,
  82         .end    = 0x0021,
  83         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
  84 }, {
  85         .name   = "timer",
  86         .start  = 0x0040,
  87         .end    = 0x005f,
  88         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
  89 }, {
  90         .name   = "keyboard",
  91         .start  = 0x0060,
  92         .end    = 0x006f,
  93         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
  94 }, {
  95         .name   = "dma page reg",
  96         .start  = 0x0080,
  97         .end    = 0x008f,
  98         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
  99 }, {
 100         .name   = "pic2",
 101         .start  = 0x00a0,
 102         .end    = 0x00a1,
 103         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
 104 }, {
 105         .name   = "dma2",
 106         .start  = 0x00c0,
 107         .end    = 0x00df,
 108         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
 109 }, {
 110         .name   = "fpu",
 111         .start  = 0x00f0,
 112         .end    = 0x00ff,
 113         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
 114 } };
 115
 116 #define STANDARD_IO_RESOURCES \
 117         (sizeof standard_io_resources / sizeof standard_io_resources[0])
 118
 119 static int __init checksum(unsigned char *rom, unsigned long length)
 120 {
 121         unsigned char *p, sum = 0;
 122
 123         for (p = rom; p < rom + length; p++)
 124                 sum += *p;
 125         return sum == 0;
 126 }
 127
 128 void __init probe_roms(void)
 129 {
 130         unsigned long start, length, upper;
 131         unsigned char *rom;
 132         int           i;
 133
 134         /* video rom */
 135         upper = adapter_rom_resources[0].start;
 136         for (start = video_rom_resource.start; start < upper; start += 2048) {
 137                 rom = isa_bus_to_virt(start);
 138                 if (!romsignature(rom))
 139                         continue;
 140
 141                 video_rom_resource.start = start;
 142
 143                 /* 0 < length <= 0x7f * 512, historically */
 144                 length = rom[2] * 512;
 145
 146                 /* if checksum okay, trust length byte */
 147                 if (length && checksum(rom, length))
 148                         video_rom_resource.end = start + length - 1;
 149
 150                 request_resource(&iomem_resource, &video_rom_resource);
 151                 break;
 152         }
 153
 154         start = (video_rom_resource.end + 1 + 2047) & ~2047UL;
 155         if (start < upper)
 156                 start = upper;
 157
 158         /* system rom */
 159         request_resource(&iomem_resource, &system_rom_resource);
 160         upper = system_rom_resource.start;
 161
 162         /* check for extension rom (ignore length byte!) */
 163         rom = isa_bus_to_virt(extension_rom_resource.start);
 164         if (romsignature(rom)) {
 165                 length = extension_rom_resource.end - extension_rom_resource.start + 1;
 166                 if (checksum(rom, length)) {
 167                         request_resource(&iomem_resource, &extension_rom_resource);
 168                         upper = extension_rom_resource.start;
 169                 }
 170         }
 171
 172         /* check for adapter roms on 2k boundaries */
 173         for (i = 0; i < ADAPTER_ROM_RESOURCES && start < upper; start += 2048) {
 174                 rom = isa_bus_to_virt(start);
 175                 if (!romsignature(rom))
 176                         continue;
 177
 178                 /* 0 < length <= 0x7f * 512, historically */
 179                 length = rom[2] * 512;
 180
 181                 /* but accept any length that fits if checksum okay */
 182                 if (!length || start + length > upper || !checksum(rom, length))
 183                         continue;
 184
 185                 adapter_rom_resources[i].start = start;
 186                 adapter_rom_resources[i].end = start + length - 1;
 187                 request_resource(&iomem_resource, &adapter_rom_resources[i]);
 188
 189                 start = adapter_rom_resources[i++].end & ~2047UL;
 190         }
 191 }
 192
 193 void __init request_graphics_resource(void)
 194 {
 195         request_resource(&iomem_resource, &vram_resource);
 196 }
 197
 198 void __init request_standard_io_resources(void)
 199 {
 200         int i;
 201
 202         for (i = 0; i < STANDARD_IO_RESOURCES; i++)
 203                 request_resource(&ioport_resource, &standard_io_resources[i]);
 204 }