xref: /OK3568_Linux_fs/kernel/arch/mips/ralink/reset.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Copyright (C) 2008-2009 Gabor Juhos <juhosg@openwrt.org>
5*4882a593Smuzhiyun  * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
6*4882a593Smuzhiyun  * Copyright (C) 2013 John Crispin <john@phrozen.org>
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <linux/pm.h>
10*4882a593Smuzhiyun #include <linux/io.h>
11*4882a593Smuzhiyun #include <linux/of.h>
12*4882a593Smuzhiyun #include <linux/delay.h>
13*4882a593Smuzhiyun #include <linux/reset-controller.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun #include <asm/reboot.h>
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun #include <asm/mach-ralink/ralink_regs.h>
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun /* Reset Control */
20*4882a593Smuzhiyun #define SYSC_REG_RESET_CTRL	0x034
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun #define RSTCTL_RESET_PCI	BIT(26)
23*4882a593Smuzhiyun #define RSTCTL_RESET_SYSTEM	BIT(0)
24*4882a593Smuzhiyun 
ralink_assert_device(struct reset_controller_dev * rcdev,unsigned long id)25*4882a593Smuzhiyun static int ralink_assert_device(struct reset_controller_dev *rcdev,
26*4882a593Smuzhiyun 				unsigned long id)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun 	u32 val;
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun 	if (id < 8)
31*4882a593Smuzhiyun 		return -1;
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun 	val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
34*4882a593Smuzhiyun 	val |= BIT(id);
35*4882a593Smuzhiyun 	rt_sysc_w32(val, SYSC_REG_RESET_CTRL);
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun 	return 0;
38*4882a593Smuzhiyun }
39*4882a593Smuzhiyun 
ralink_deassert_device(struct reset_controller_dev * rcdev,unsigned long id)40*4882a593Smuzhiyun static int ralink_deassert_device(struct reset_controller_dev *rcdev,
41*4882a593Smuzhiyun 				  unsigned long id)
42*4882a593Smuzhiyun {
43*4882a593Smuzhiyun 	u32 val;
44*4882a593Smuzhiyun 
45*4882a593Smuzhiyun 	if (id < 8)
46*4882a593Smuzhiyun 		return -1;
47*4882a593Smuzhiyun 
48*4882a593Smuzhiyun 	val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
49*4882a593Smuzhiyun 	val &= ~BIT(id);
50*4882a593Smuzhiyun 	rt_sysc_w32(val, SYSC_REG_RESET_CTRL);
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun 	return 0;
53*4882a593Smuzhiyun }
54*4882a593Smuzhiyun 
ralink_reset_device(struct reset_controller_dev * rcdev,unsigned long id)55*4882a593Smuzhiyun static int ralink_reset_device(struct reset_controller_dev *rcdev,
56*4882a593Smuzhiyun 			       unsigned long id)
57*4882a593Smuzhiyun {
58*4882a593Smuzhiyun 	ralink_assert_device(rcdev, id);
59*4882a593Smuzhiyun 	return ralink_deassert_device(rcdev, id);
60*4882a593Smuzhiyun }
61*4882a593Smuzhiyun 
62*4882a593Smuzhiyun static const struct reset_control_ops reset_ops = {
63*4882a593Smuzhiyun 	.reset = ralink_reset_device,
64*4882a593Smuzhiyun 	.assert = ralink_assert_device,
65*4882a593Smuzhiyun 	.deassert = ralink_deassert_device,
66*4882a593Smuzhiyun };
67*4882a593Smuzhiyun 
68*4882a593Smuzhiyun static struct reset_controller_dev reset_dev = {
69*4882a593Smuzhiyun 	.ops			= &reset_ops,
70*4882a593Smuzhiyun 	.owner			= THIS_MODULE,
71*4882a593Smuzhiyun 	.nr_resets		= 32,
72*4882a593Smuzhiyun 	.of_reset_n_cells	= 1,
73*4882a593Smuzhiyun };
74*4882a593Smuzhiyun 
ralink_rst_init(void)75*4882a593Smuzhiyun void ralink_rst_init(void)
76*4882a593Smuzhiyun {
77*4882a593Smuzhiyun 	reset_dev.of_node = of_find_compatible_node(NULL, NULL,
78*4882a593Smuzhiyun 						"ralink,rt2880-reset");
79*4882a593Smuzhiyun 	if (!reset_dev.of_node)
80*4882a593Smuzhiyun 		pr_err("Failed to find reset controller node");
81*4882a593Smuzhiyun 	else
82*4882a593Smuzhiyun 		reset_controller_register(&reset_dev);
83*4882a593Smuzhiyun }
84*4882a593Smuzhiyun 
ralink_restart(char * command)85*4882a593Smuzhiyun static void ralink_restart(char *command)
86*4882a593Smuzhiyun {
87*4882a593Smuzhiyun 	if (IS_ENABLED(CONFIG_PCI)) {
88*4882a593Smuzhiyun 		rt_sysc_m32(0, RSTCTL_RESET_PCI, SYSC_REG_RESET_CTRL);
89*4882a593Smuzhiyun 		mdelay(50);
90*4882a593Smuzhiyun 	}
91*4882a593Smuzhiyun 
92*4882a593Smuzhiyun 	local_irq_disable();
93*4882a593Smuzhiyun 	rt_sysc_w32(RSTCTL_RESET_SYSTEM, SYSC_REG_RESET_CTRL);
94*4882a593Smuzhiyun 	unreachable();
95*4882a593Smuzhiyun }
96*4882a593Smuzhiyun 
mips_reboot_setup(void)97*4882a593Smuzhiyun static int __init mips_reboot_setup(void)
98*4882a593Smuzhiyun {
99*4882a593Smuzhiyun 	_machine_restart = ralink_restart;
100*4882a593Smuzhiyun 
101*4882a593Smuzhiyun 	return 0;
102*4882a593Smuzhiyun }
103*4882a593Smuzhiyun 
104*4882a593Smuzhiyun arch_initcall(mips_reboot_setup);
105