39 строки
1.2 KiB
C
39 строки
1.2 KiB
C
|
/*
|
||
|
|
* linux/arch/alpha/kernel/ns87312.c
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/init.h>
|
||
|
|
#include <asm/io.h>
|
||
|
|
#include "proto.h"
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
* The SRM console *disables* the IDE interface, this code ensures it's
|
||
|
|
* enabled.
|
||
|
|
*
|
||
|
|
* This code bangs on a control register of the 87312 Super I/O chip
|
||
|
|
* that implements parallel port/serial ports/IDE/FDI. Depending on
|
||
|
|
* the motherboard, the Super I/O chip can be configured through a
|
||
|
|
* pair of registers that are located either at I/O ports 0x26e/0x26f
|
||
|
|
* or 0x398/0x399. Unfortunately, autodetecting which base address is
|
||
|
|
* in use works only once (right after a reset). The Super I/O chip
|
||
|
|
* has the additional quirk that configuration register data must be
|
||
|
|
* written twice (I believe this is a safety feature to prevent
|
||
|
|
* accidental modification---fun, isn't it?).
|
||
|
|
*/
|
||
|
|
|
||
|
|
void __init
|
||
|
|
ns87312_enable_ide(long ide_base)
|
||
|
|
{
|
||
|
|
int data;
|
||
|
|
unsigned long flags;
|
||
|
|
|
||
|
|
local_irq_save(flags);
|
||
|
|
outb(0, ide_base); /* set the index register for reg #0 */
|
||
|
|
data = inb(ide_base+1); /* read the current contents */
|
||
|
|
outb(0, ide_base); /* set the index register for reg #0 */
|
||
|
|
outb(data | 0x40, ide_base+1); /* turn on IDE */
|
||
|
|
outb(data | 0x40, ide_base+1); /* turn on IDE, really! */
|
||
|
|
local_irq_restore(flags);
|
||
|
|
}
|