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 25 static int ralink_assert_device(struct reset_controller_dev *rcdev, 26 unsigned long id) 27 { 28 u32 val; 29 30 if (id == 0) 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 40 static int ralink_deassert_device(struct reset_controller_dev *rcdev, 41 unsigned long id) 42 { 43 u32 val; 44 45 if (id == 0) 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 55 static 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 62 static const struct reset_control_ops reset_ops = { 63 .reset = ralink_reset_device, 64 .assert = ralink_assert_device, 65 .deassert = ralink_deassert_device, 66 }; 67 68 static 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 75 void 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 85 static 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 97 static int __init mips_reboot_setup(void) 98 { 99 _machine_restart = ralink_restart; 100 101 return 0; 102 } 103 104 arch_initcall(mips_reboot_setup); 105