Contributors: 8
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| René Herman |
178 |
44.61% |
1 |
10.00% |
| Ingo Molnar |
173 |
43.36% |
3 |
30.00% |
| Chuck Ebbert |
31 |
7.77% |
1 |
10.00% |
| Cyrill V. Gorcunov |
9 |
2.26% |
1 |
10.00% |
| Jaswinder Singh Rajput |
4 |
1.00% |
1 |
10.00% |
| Christoph Hellwig |
2 |
0.50% |
1 |
10.00% |
| Paul Gortmaker |
1 |
0.25% |
1 |
10.00% |
| Greg Kroah-Hartman |
1 |
0.25% |
1 |
10.00% |
| Total |
399 |
|
10 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* 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/export.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/dmi.h>
#include <linux/io.h>
int io_delay_type __read_mostly = CONFIG_DEFAULT_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) {
pr_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 const struct dmi_system_id io_delay_0xed_port_dmi_table[] __initconst = {
{
.callback = dmi_io_delay_0xed_port,
.ident = "Compaq Presario V6000",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "Quanta"),
DMI_MATCH(DMI_BOARD_NAME, "30B7")
}
},
{
.callback = dmi_io_delay_0xed_port,
.ident = "HP Pavilion dv9000z",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "Quanta"),
DMI_MATCH(DMI_BOARD_NAME, "30B9")
}
},
{
.callback = dmi_io_delay_0xed_port,
.ident = "HP Pavilion dv6000",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "Quanta"),
DMI_MATCH(DMI_BOARD_NAME, "30B8")
}
},
{
.callback = dmi_io_delay_0xed_port,
.ident = "HP Pavilion tx1000",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "Quanta"),
DMI_MATCH(DMI_BOARD_NAME, "30BF")
}
},
{
.callback = dmi_io_delay_0xed_port,
.ident = "Presario F700",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "Quanta"),
DMI_MATCH(DMI_BOARD_NAME, "30D3")
}
},
{ }
};
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 (!s)
return -EINVAL;
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);