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