xref: /openbmc/linux/arch/mips/pic32/common/reset.c (revision 68198dca)
1 /*
2  * Joshua Henderson <joshua.henderson@microchip.com>
3  * Copyright (C) 2015 Microchip Technology Inc.  All rights reserved.
4  *
5  *  This program is free software; you can distribute it and/or modify it
6  *  under the terms of the GNU General Public License (Version 2) as
7  *  published by the Free Software Foundation.
8  *
9  *  This program is distributed in the hope it will be useful, but WITHOUT
10  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  *  for more details.
13  */
14 #include <linux/init.h>
15 #include <linux/pm.h>
16 #include <asm/reboot.h>
17 #include <asm/mach-pic32/pic32.h>
18 
19 #define PIC32_RSWRST		0x10
20 
21 static void pic32_halt(void)
22 {
23 	while (1) {
24 		__asm__(".set push;\n"
25 			".set arch=r4000;\n"
26 			"wait;\n"
27 			".set pop;\n"
28 		);
29 	}
30 }
31 
32 static void pic32_machine_restart(char *command)
33 {
34 	void __iomem *reg =
35 		ioremap(PIC32_BASE_RESET + PIC32_RSWRST, sizeof(u32));
36 
37 	pic32_syskey_unlock();
38 
39 	/* magic write/read */
40 	__raw_writel(1, reg);
41 	(void)__raw_readl(reg);
42 
43 	pic32_halt();
44 }
45 
46 static void pic32_machine_halt(void)
47 {
48 	local_irq_disable();
49 
50 	pic32_halt();
51 }
52 
53 static int __init mips_reboot_setup(void)
54 {
55 	_machine_restart = pic32_machine_restart;
56 	_machine_halt = pic32_machine_halt;
57 	pm_power_off = pic32_machine_halt;
58 
59 	return 0;
60 }
61 
62 arch_initcall(mips_reboot_setup);
63