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);
16 pr_debug("%x reading 4 from %x: %x\n", slot, offset, v);
20 u8 read_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset)
23 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
24 v = inb(0xcfc + (offset&3));
25 pr_debug("%x reading 1 from %x: %x\n", slot, offset, v);
29 u16 read_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset)
32 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
33 v = inw(0xcfc + (offset&2));
34 pr_debug("%x reading 2 from %x: %x\n", slot, offset, v);
38 void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset,
41 pr_debug("%x writing to %x: %x\n", slot, offset, val);
42 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
46 void write_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset, u8 val)
48 pr_debug("%x writing to %x: %x\n", slot, offset, val);
49 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
50 outb(val, 0xcfc + (offset&3));
53 void write_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset, u16 val)
55 pr_debug("%x writing to %x: %x\n", slot, offset, val);
56 outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
57 outw(val, 0xcfc + (offset&2));
60 int early_pci_allowed(void)
62 return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) ==
66 void early_dump_pci_device(u8 bus, u8 slot, u8 func)
72 printk(KERN_INFO "pci 0000:%02x:%02x.%d config space:",
75 for (i = 0; i < 256; i += 4) {
79 val = read_pci_config(bus, slot, func, i);
80 for (j = 0; j < 4; j++) {
81 printk(" %02x", val & 0xff);
88 void early_dump_pci_devices(void)
90 unsigned bus, slot, func;
92 if (!early_pci_allowed())
95 for (bus = 0; bus < 256; bus++) {
96 for (slot = 0; slot < 32; slot++) {
97 for (func = 0; func < 8; func++) {
101 class = read_pci_config(bus, slot, func,
103 if (class == 0xffffffff)
106 early_dump_pci_device(bus, slot, func);
109 type = read_pci_config_byte(bus, slot,