xref: /openbmc/linux/arch/x86/pci/early.c (revision e7891c733f9b26c851edde50cf886a30bd133dbd)
1fb9aa6f1SThomas Gleixner #include <linux/kernel.h>
2fb9aa6f1SThomas Gleixner #include <linux/pci.h>
3fb9aa6f1SThomas Gleixner #include <asm/pci-direct.h>
4fb9aa6f1SThomas Gleixner #include <asm/io.h>
5fb9aa6f1SThomas Gleixner #include "pci.h"
6fb9aa6f1SThomas Gleixner 
7fb9aa6f1SThomas Gleixner /* Direct PCI access. This is used for PCI accesses in early boot before
8fb9aa6f1SThomas Gleixner    the PCI subsystem works. */
9fb9aa6f1SThomas Gleixner 
10fb9aa6f1SThomas Gleixner #define PDprintk(x...)
11fb9aa6f1SThomas Gleixner 
12fb9aa6f1SThomas Gleixner u32 read_pci_config(u8 bus, u8 slot, u8 func, u8 offset)
13fb9aa6f1SThomas Gleixner {
14fb9aa6f1SThomas Gleixner 	u32 v;
15fb9aa6f1SThomas Gleixner 	outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
16fb9aa6f1SThomas Gleixner 	v = inl(0xcfc);
17fb9aa6f1SThomas Gleixner 	if (v != 0xffffffff)
18fb9aa6f1SThomas Gleixner 		PDprintk("%x reading 4 from %x: %x\n", slot, offset, v);
19fb9aa6f1SThomas Gleixner 	return v;
20fb9aa6f1SThomas Gleixner }
21fb9aa6f1SThomas Gleixner 
22fb9aa6f1SThomas Gleixner u8 read_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset)
23fb9aa6f1SThomas Gleixner {
24fb9aa6f1SThomas Gleixner 	u8 v;
25fb9aa6f1SThomas Gleixner 	outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
26fb9aa6f1SThomas Gleixner 	v = inb(0xcfc + (offset&3));
27fb9aa6f1SThomas Gleixner 	PDprintk("%x reading 1 from %x: %x\n", slot, offset, v);
28fb9aa6f1SThomas Gleixner 	return v;
29fb9aa6f1SThomas Gleixner }
30fb9aa6f1SThomas Gleixner 
31fb9aa6f1SThomas Gleixner u16 read_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset)
32fb9aa6f1SThomas Gleixner {
33fb9aa6f1SThomas Gleixner 	u16 v;
34fb9aa6f1SThomas Gleixner 	outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
35fb9aa6f1SThomas Gleixner 	v = inw(0xcfc + (offset&2));
36fb9aa6f1SThomas Gleixner 	PDprintk("%x reading 2 from %x: %x\n", slot, offset, v);
37fb9aa6f1SThomas Gleixner 	return v;
38fb9aa6f1SThomas Gleixner }
39fb9aa6f1SThomas Gleixner 
40fb9aa6f1SThomas Gleixner void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset,
41fb9aa6f1SThomas Gleixner 				    u32 val)
42fb9aa6f1SThomas Gleixner {
43fb9aa6f1SThomas Gleixner 	PDprintk("%x writing to %x: %x\n", slot, offset, val);
44fb9aa6f1SThomas Gleixner 	outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
45fb9aa6f1SThomas Gleixner 	outl(val, 0xcfc);
46fb9aa6f1SThomas Gleixner }
47fb9aa6f1SThomas Gleixner 
48fb9aa6f1SThomas Gleixner void write_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset, u8 val)
49fb9aa6f1SThomas Gleixner {
50fb9aa6f1SThomas Gleixner 	PDprintk("%x writing to %x: %x\n", slot, offset, val);
51fb9aa6f1SThomas Gleixner 	outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
52*e7891c73SYinghai Lu 	outb(val, 0xcfc + (offset&3));
53*e7891c73SYinghai Lu }
54*e7891c73SYinghai Lu 
55*e7891c73SYinghai Lu void write_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset, u16 val)
56*e7891c73SYinghai Lu {
57*e7891c73SYinghai Lu 	PDprintk("%x writing to %x: %x\n", slot, offset, val);
58*e7891c73SYinghai Lu 	outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
59*e7891c73SYinghai Lu 	outw(val, 0xcfc + (offset&2));
60fb9aa6f1SThomas Gleixner }
61fb9aa6f1SThomas Gleixner 
62fb9aa6f1SThomas Gleixner int early_pci_allowed(void)
63fb9aa6f1SThomas Gleixner {
64fb9aa6f1SThomas Gleixner 	return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) ==
65fb9aa6f1SThomas Gleixner 			PCI_PROBE_CONF1;
66fb9aa6f1SThomas Gleixner }
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