arch/x86/pci/early.c

   1 #include <linux/kernel.h>
   2 #include <linux/pci.h>
   3 #include <asm/pci-direct.h>
   4 #include <asm/io.h>
   5 #include <asm/pci_x86.h>
   6
   7 /* Direct PCI access. This is used for PCI accesses in early boot before
   8    the PCI subsystem works. */
   9
  10 u32 read_pci_config(u8 bus, u8 slot, u8 func, u8 offset)
  11 {
  12         u32 v;
  13         outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
  14         v = inl(0xcfc);
  15         return v;
  16 }
  17
  18 u8 read_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset)
  19 {
  20         u8 v;
  21         outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
  22         v = inb(0xcfc + (offset&3));
  23         return v;
  24 }
  25
  26 u16 read_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset)
  27 {
  28         u16 v;
  29         outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
  30         v = inw(0xcfc + (offset&2));
  31         return v;
  32 }
  33
  34 void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset,
  35                                     u32 val)
  36 {
  37         outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
  38         outl(val, 0xcfc);
  39 }
  40
  41 void write_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset, u8 val)
  42 {
  43         outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
  44         outb(val, 0xcfc + (offset&3));
  45 }
  46
  47 void write_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset, u16 val)
  48 {
  49         outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
  50         outw(val, 0xcfc + (offset&2));
  51 }
  52
  53 int early_pci_allowed(void)
  54 {
  55         return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) ==
  56                         PCI_PROBE_CONF1;
  57 }
  58
  59 void early_dump_pci_device(u8 bus, u8 slot, u8 func)
  60 {
  61         int i;
  62         int j;
  63         u32 val;
  64
  65         printk(KERN_INFO "pci 0000:%02x:%02x.%d config space:",
  66                bus, slot, func);
  67
  68         for (i = 0; i < 256; i += 4) {
  69                 if (!(i & 0x0f))
  70                         printk("\n  %02x:",i);
  71
  72                 val = read_pci_config(bus, slot, func, i);
  73                 for (j = 0; j < 4; j++) {
  74                         printk(" %02x", val & 0xff);
  75                         val >>= 8;
  76                 }
  77         }
  78         printk("\n");
  79 }
  80
  81 void early_dump_pci_devices(void)
  82 {
  83         unsigned bus, slot, func;
  84
  85         if (!early_pci_allowed())
  86                 return;
  87
  88         for (bus = 0; bus < 256; bus++) {
  89                 for (slot = 0; slot < 32; slot++) {
  90                         for (func = 0; func < 8; func++) {
  91                                 u32 class;
  92                                 u8 type;
  93
  94                                 class = read_pci_config(bus, slot, func,
  95                                                         PCI_CLASS_REVISION);
  96                                 if (class == 0xffffffff)
  97                                         continue;
  98
  99                                 early_dump_pci_device(bus, slot, func);
 100
 101                                 if (func == 0) {
 102                                         type = read_pci_config_byte(bus, slot,
 103                                                                     func,
 104                                                                PCI_HEADER_TYPE);
 105                                         if (!(type & 0x80))
 106                                                 break;
 107                                 }
 108                         }
 109                 }
 110         }
 111 }