1 // SPDX-License-Identifier: GPL-2.0-only 2 // Copyright (C) 2013 Broadcom Corporation 3 4 #include <linux/bitops.h> 5 #include <linux/device.h> 6 #include <linux/errno.h> 7 #include <linux/init.h> 8 #include <linux/io.h> 9 #include <linux/jiffies.h> 10 #include <linux/notifier.h> 11 #include <linux/of_address.h> 12 #include <linux/of_irq.h> 13 #include <linux/of_platform.h> 14 #include <linux/platform_device.h> 15 #include <linux/printk.h> 16 #include <linux/reboot.h> 17 #include <linux/regmap.h> 18 #include <linux/smp.h> 19 #include <linux/mfd/syscon.h> 20 21 static struct regmap *regmap; 22 static u32 rst_src_en; 23 static u32 sw_mstr_rst; 24 25 struct reset_reg_mask { 26 u32 rst_src_en_mask; 27 u32 sw_mstr_rst_mask; 28 }; 29 30 static const struct reset_reg_mask *reset_masks; 31 32 static int brcmstb_restart_handler(struct sys_off_data *data) 33 { 34 int rc; 35 u32 tmp; 36 37 rc = regmap_write(regmap, rst_src_en, reset_masks->rst_src_en_mask); 38 if (rc) { 39 pr_err("failed to write rst_src_en (%d)\n", rc); 40 return NOTIFY_DONE; 41 } 42 43 rc = regmap_read(regmap, rst_src_en, &tmp); 44 if (rc) { 45 pr_err("failed to read rst_src_en (%d)\n", rc); 46 return NOTIFY_DONE; 47 } 48 49 rc = regmap_write(regmap, sw_mstr_rst, reset_masks->sw_mstr_rst_mask); 50 if (rc) { 51 pr_err("failed to write sw_mstr_rst (%d)\n", rc); 52 return NOTIFY_DONE; 53 } 54 55 rc = regmap_read(regmap, sw_mstr_rst, &tmp); 56 if (rc) { 57 pr_err("failed to read sw_mstr_rst (%d)\n", rc); 58 return NOTIFY_DONE; 59 } 60 61 return NOTIFY_DONE; 62 } 63 64 static const struct reset_reg_mask reset_bits_40nm = { 65 .rst_src_en_mask = BIT(0), 66 .sw_mstr_rst_mask = BIT(0), 67 }; 68 69 static const struct reset_reg_mask reset_bits_65nm = { 70 .rst_src_en_mask = BIT(3), 71 .sw_mstr_rst_mask = BIT(31), 72 }; 73 74 static int brcmstb_reboot_probe(struct platform_device *pdev) 75 { 76 int rc; 77 struct device_node *np = pdev->dev.of_node; 78 unsigned int args[2]; 79 80 reset_masks = device_get_match_data(&pdev->dev); 81 if (!reset_masks) { 82 pr_err("failed to get match data\n"); 83 return -EINVAL; 84 } 85 86 regmap = syscon_regmap_lookup_by_phandle_args(np, "syscon", ARRAY_SIZE(args), args); 87 if (IS_ERR(regmap)) { 88 pr_err("failed to get syscon phandle\n"); 89 return -EINVAL; 90 } 91 rst_src_en = args[0]; 92 sw_mstr_rst = args[1]; 93 94 rc = devm_register_sys_off_handler(&pdev->dev, SYS_OFF_MODE_RESTART, 95 128, brcmstb_restart_handler, NULL); 96 if (rc) 97 dev_err(&pdev->dev, 98 "cannot register restart handler (err=%d)\n", rc); 99 100 return rc; 101 } 102 103 static const struct of_device_id of_match[] = { 104 { .compatible = "brcm,brcmstb-reboot", .data = &reset_bits_40nm }, 105 { .compatible = "brcm,bcm7038-reboot", .data = &reset_bits_65nm }, 106 {}, 107 }; 108 109 static struct platform_driver brcmstb_reboot_driver = { 110 .probe = brcmstb_reboot_probe, 111 .driver = { 112 .name = "brcmstb-reboot", 113 .of_match_table = of_match, 114 }, 115 }; 116 117 static int __init brcmstb_reboot_init(void) 118 { 119 return platform_driver_register(&brcmstb_reboot_driver); 120 } 121 subsys_initcall(brcmstb_reboot_init); 122