1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
#include "pci.h"
#include "string.h"
void pci_controller_init( pci_controller_t *controller )
{
memset( controller, 0, sizeof( pci_controller_t ) );
port32_init( &controller->command_port, 0xCF8 );
port32_init( &controller->data_port, 0xCFC );
}
static uint32_t compute_id( uint16_t bus, uint16_t device, uint16_t function, uint32_t offset )
{
uint32_t id;
id = ( 0x01 << 31 )
| ( ( bus & 0xFF ) << 16 )
| ( ( device & 0x1F ) << 11 )
| ( ( function & 0x07 ) << 8 )
| ( offset & 0xFC );
return id;
}
uint16_t pci_controller_read( pci_controller_t *controller, uint16_t bus, uint16_t device, uint16_t function, uint32_t offset )
{
uint32_t id = compute_id( bus, device, function, offset );
port32_write( &controller->command_port, id );
uint32_t data = port32_read( &controller->data_port );
// we get 256 byte data blocks aligned to 32-bit addresses
// for each offset
data = data >> ( ( 8 * ( offset % 4 ) ) & 0xFFFF );
return data;
}
void pci_controller_write( pci_controller_t *controller, uint16_t bus, uint16_t device, uint16_t function, uint32_t offset, uint32_t data )
{
uint32_t id = compute_id( bus, device, function, offset );
port32_write( &controller->command_port, id );
port32_write( &controller->data_port, data );
}
|
