1 /* 2 * This program is free software; you can redistribute it and/or modify it 3 * under the terms of the GNU General Public License version 2 as published 4 * by the Free Software Foundation. 5 * 6 * Copyright (C) 2008-2009 Gabor Juhos <juhosg@openwrt.org> 7 * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org> 8 * Copyright (C) 2013 John Crispin <john@phrozen.org> 9 */ 10 11 #include <linux/pm.h> 12 #include <linux/io.h> 13 #include <linux/of.h> 14 #include <linux/delay.h> 15 #include <linux/reset-controller.h> 16 17 #include <asm/reboot.h> 18 19 #include <asm/mach-ralink/ralink_regs.h> 20 21 /* Reset Control */ 22 #define SYSC_REG_RESET_CTRL 0x034 23 24 #define RSTCTL_RESET_PCI BIT(26) 25 #define RSTCTL_RESET_SYSTEM BIT(0) 26 27 static int ralink_assert_device(struct reset_controller_dev *rcdev, 28 unsigned long id) 29 { 30 u32 val; 31 32 if (id < 8) 33 return -1; 34 35 val = rt_sysc_r32(SYSC_REG_RESET_CTRL); 36 val |= BIT(id); 37 rt_sysc_w32(val, SYSC_REG_RESET_CTRL); 38 39 return 0; 40 } 41 42 static int ralink_deassert_device(struct reset_controller_dev *rcdev, 43 unsigned long id) 44 { 45 u32 val; 46 47 if (id < 8) 48 return -1; 49 50 val = rt_sysc_r32(SYSC_REG_RESET_CTRL); 51 val &= ~BIT(id); 52 rt_sysc_w32(val, SYSC_REG_RESET_CTRL); 53 54 return 0; 55 } 56 57 static int ralink_reset_device(struct reset_controller_dev *rcdev, 58 unsigned long id) 59 { 60 ralink_assert_device(rcdev, id); 61 return ralink_deassert_device(rcdev, id); 62 } 63 64 static const struct reset_control_ops reset_ops = { 65 .reset = ralink_reset_device, 66 .assert = ralink_assert_device, 67 .deassert = ralink_deassert_device, 68 }; 69 70 static struct reset_controller_dev reset_dev = { 71 .ops = &reset_ops, 72 .owner = THIS_MODULE, 73 .nr_resets = 32, 74 .of_reset_n_cells = 1, 75 }; 76 77 void ralink_rst_init(void) 78 { 79 reset_dev.of_node = of_find_compatible_node(NULL, NULL, 80 "ralink,rt2880-reset"); 81 if (!reset_dev.of_node) 82 pr_err("Failed to find reset controller node"); 83 else 84 reset_controller_register(&reset_dev); 85 } 86 87 static void ralink_restart(char *command) 88 { 89 if (IS_ENABLED(CONFIG_PCI)) { 90 rt_sysc_m32(0, RSTCTL_RESET_PCI, SYSC_REG_RESET_CTRL); 91 mdelay(50); 92 } 93 94 local_irq_disable(); 95 rt_sysc_w32(RSTCTL_RESET_SYSTEM, SYSC_REG_RESET_CTRL); 96 unreachable(); 97 } 98 99 static int __init mips_reboot_setup(void) 100 { 101 _machine_restart = ralink_restart; 102 103 return 0; 104 } 105 106 arch_initcall(mips_reboot_setup); 107