1 #include <linux/kernel.h>
3 #include <asm/pci-direct.h>
5 #include <asm/pci_x86.h>
7 /* Direct PCI access. This is used for PCI accesses in early boot before
8 the PCI subsystem works. */
10 u32 read_pci_config(u8 bus, u8 slot, u8 func, u8 offset)
13 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
18 u8 read_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset)
21 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
22 v = inb(0xcfc + (offset&3));
26 u16 read_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset)
29 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
30 v = inw(0xcfc + (offset&2));
34 void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset,
37 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
41 void write_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset, u8 val)
43 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
44 outb(val, 0xcfc + (offset&3));
47 void write_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset, u16 val)
49 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
50 outw(val, 0xcfc + (offset&2));
53 int early_pci_allowed(void)
55 return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) ==
59 void early_dump_pci_device(u8 bus, u8 slot, u8 func)
65 printk(KERN_INFO "pci 0000:%02x:%02x.%d config space:",
68 for (i = 0; i < 256; i += 4) {
72 val = read_pci_config(bus, slot, func, i);
73 for (j = 0; j < 4; j++) {
74 printk(" %02x", val & 0xff);
81 void early_dump_pci_devices(void)
83 unsigned bus, slot, func;
85 if (!early_pci_allowed())
88 for (bus = 0; bus < 256; bus++) {
89 for (slot = 0; slot < 32; slot++) {
90 for (func = 0; func < 8; func++) {
94 class = read_pci_config(bus, slot, func,
96 if (class == 0xffffffff)
99 early_dump_pci_device(bus, slot, func);
102 type = read_pci_config_byte(bus, slot,