1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/kernel.h> |
3 | #include <linux/pci.h> |
4 | #include <asm/pci-direct.h> |
5 | #include <asm/io.h> |
6 | #include <asm/pci_x86.h> |
7 | |
8 | /* Direct PCI access. This is used for PCI accesses in early boot before |
9 | the PCI subsystem works. */ |
10 | |
11 | u32 read_pci_config(u8 bus, u8 slot, u8 func, u8 offset) |
12 | { |
13 | u32 v; |
14 | outl(value: 0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, port: 0xcf8); |
15 | v = inl(port: 0xcfc); |
16 | return v; |
17 | } |
18 | |
19 | u8 read_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset) |
20 | { |
21 | u8 v; |
22 | outl(value: 0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, port: 0xcf8); |
23 | v = inb(port: 0xcfc + (offset&3)); |
24 | return v; |
25 | } |
26 | |
27 | u16 read_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset) |
28 | { |
29 | u16 v; |
30 | outl(value: 0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, port: 0xcf8); |
31 | v = inw(port: 0xcfc + (offset&2)); |
32 | return v; |
33 | } |
34 | |
35 | void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset, |
36 | u32 val) |
37 | { |
38 | outl(value: 0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, port: 0xcf8); |
39 | outl(value: val, port: 0xcfc); |
40 | } |
41 | |
42 | void write_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset, u8 val) |
43 | { |
44 | outl(value: 0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, port: 0xcf8); |
45 | outb(value: val, port: 0xcfc + (offset&3)); |
46 | } |
47 | |
48 | void write_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset, u16 val) |
49 | { |
50 | outl(value: 0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, port: 0xcf8); |
51 | outw(value: val, port: 0xcfc + (offset&2)); |
52 | } |
53 | |
54 | int early_pci_allowed(void) |
55 | { |
56 | return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) == |
57 | PCI_PROBE_CONF1; |
58 | } |
59 | |
60 | |