xref: /OK3568_Linux_fs/kernel/arch/mips/sni/reset.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  *  linux/arch/mips/sni/process.c
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  *  Reset a SNI machine.
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun #include <linux/delay.h>
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <asm/io.h>
10*4882a593Smuzhiyun #include <asm/reboot.h>
11*4882a593Smuzhiyun #include <asm/sni.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun /*
14*4882a593Smuzhiyun  * This routine reboots the machine by asking the keyboard
15*4882a593Smuzhiyun  * controller to pulse the reset-line low. We try that for a while,
16*4882a593Smuzhiyun  * and if it doesn't work, we do some other stupid things.
17*4882a593Smuzhiyun  */
kb_wait(void)18*4882a593Smuzhiyun static inline void kb_wait(void)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun 	int i;
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun 	for (i = 0; i < 0x10000; i++)
23*4882a593Smuzhiyun 		if ((inb_p(0x64) & 0x02) == 0)
24*4882a593Smuzhiyun 			break;
25*4882a593Smuzhiyun }
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun /* XXX This ends up at the ARC firmware prompt ...  */
sni_machine_restart(char * command)28*4882a593Smuzhiyun void sni_machine_restart(char *command)
29*4882a593Smuzhiyun {
30*4882a593Smuzhiyun 	int i;
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun 	/* This does a normal via the keyboard controller like a PC.
33*4882a593Smuzhiyun 	   We can do that easier ...  */
34*4882a593Smuzhiyun 	local_irq_disable();
35*4882a593Smuzhiyun 	for (;;) {
36*4882a593Smuzhiyun 		for (i = 0; i < 100; i++) {
37*4882a593Smuzhiyun 			kb_wait();
38*4882a593Smuzhiyun 			udelay(50);
39*4882a593Smuzhiyun 			outb_p(0xfe, 0x64);	 /* pulse reset low */
40*4882a593Smuzhiyun 			udelay(50);
41*4882a593Smuzhiyun 		}
42*4882a593Smuzhiyun 	}
43*4882a593Smuzhiyun }
44*4882a593Smuzhiyun 
sni_machine_power_off(void)45*4882a593Smuzhiyun void sni_machine_power_off(void)
46*4882a593Smuzhiyun {
47*4882a593Smuzhiyun 	*(volatile unsigned char *)PCIMT_CSWCSM = 0xfd;
48*4882a593Smuzhiyun }
49