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
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
/*
* I/O delay strategies for inb_p/outb_p
*
* Allow for a DMI based override of port 0x80, needed for certain HP laptops
* and possibly other systems. Also allow for the gradual elimination of
* outb_p/inb_p API uses.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/dmi.h>
#include <asm/io.h>
int io_delay_type __read_mostly = CONFIG_DEFAULT_IO_DELAY_TYPE;
EXPORT_SYMBOL_GPL(io_delay_type);
static int __initdata io_delay_override;
/*
* Paravirt wants native_io_delay to be a constant.
*/
void native_io_delay(void)
{
switch (io_delay_type) {
default:
case CONFIG_IO_DELAY_TYPE_0X80:
asm volatile ("outb %al, $0x80");
break;
case CONFIG_IO_DELAY_TYPE_0XED:
asm volatile ("outb %al, $0xed");
break;
case CONFIG_IO_DELAY_TYPE_UDELAY:
/*
* 2 usecs is an upper-bound for the outb delay but
* note that udelay doesn't have the bus-level
* side-effects that outb does, nor does udelay() have
* precise timings during very early bootup (the delays
* are shorter until calibrated):
*/
udelay(2);
case CONFIG_IO_DELAY_TYPE_NONE:
break;
}
}
EXPORT_SYMBOL(native_io_delay);
static int __init dmi_io_delay_0xed_port(const struct dmi_system_id *id)
{
if (io_delay_type == CONFIG_IO_DELAY_TYPE_0X80) {
printk(KERN_NOTICE "%s: using 0xed I/O delay port\n",
id->ident);
io_delay_type = CONFIG_IO_DELAY_TYPE_0XED;
}
return 0;
}
/*
* Quirk table for systems that misbehave (lock up, etc.) if port
* 0x80 is used:
*/
static struct dmi_system_id __initdata io_delay_0xed_port_dmi_table[] = {
{
.callback = dmi_io_delay_0xed_port,
.ident = "HP Pavilion dv9000z",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "Quanta"),
DMI_MATCH(DMI_BOARD_NAME, "30B9")
}
},
{ }
};
void __init io_delay_init(void)
{
if (!io_delay_override)
dmi_check_system(io_delay_0xed_port_dmi_table);
}
static int __init io_delay_param(char *s)
{
if (!strcmp(s, "0x80"))
io_delay_type = CONFIG_IO_DELAY_TYPE_0X80;
else if (!strcmp(s, "0xed"))
io_delay_type = CONFIG_IO_DELAY_TYPE_0XED;
else if (!strcmp(s, "udelay"))
io_delay_type = CONFIG_IO_DELAY_TYPE_UDELAY;
else if (!strcmp(s, "none"))
io_delay_type = CONFIG_IO_DELAY_TYPE_NONE;
else
return -EINVAL;
io_delay_override = 1;
return 0;
}
early_param("io_delay", io_delay_param);
|
