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 | #define RESET_SOURCE_ENABLE_REG 1 |
22 | #define SW_MASTER_RESET_REG 2 |
23 | |
24 | static struct regmap *regmap; |
25 | static u32 rst_src_en; |
26 | static u32 sw_mstr_rst; |
27 | |
28 | struct reset_reg_mask { |
29 | u32 rst_src_en_mask; |
30 | u32 sw_mstr_rst_mask; |
31 | }; |
32 | |
33 | static const struct reset_reg_mask *reset_masks; |
34 | |
35 | static int brcmstb_restart_handler(struct notifier_block *this, |
36 | unsigned long mode, void *cmd) |
37 | { |
38 | int rc; |
39 | u32 tmp; |
40 | |
41 | rc = regmap_write(map: regmap, reg: rst_src_en, val: reset_masks->rst_src_en_mask); |
42 | if (rc) { |
43 | pr_err("failed to write rst_src_en (%d)\n" , rc); |
44 | return NOTIFY_DONE; |
45 | } |
46 | |
47 | rc = regmap_read(map: regmap, reg: rst_src_en, val: &tmp); |
48 | if (rc) { |
49 | pr_err("failed to read rst_src_en (%d)\n" , rc); |
50 | return NOTIFY_DONE; |
51 | } |
52 | |
53 | rc = regmap_write(map: regmap, reg: sw_mstr_rst, val: reset_masks->sw_mstr_rst_mask); |
54 | if (rc) { |
55 | pr_err("failed to write sw_mstr_rst (%d)\n" , rc); |
56 | return NOTIFY_DONE; |
57 | } |
58 | |
59 | rc = regmap_read(map: regmap, reg: sw_mstr_rst, val: &tmp); |
60 | if (rc) { |
61 | pr_err("failed to read sw_mstr_rst (%d)\n" , rc); |
62 | return NOTIFY_DONE; |
63 | } |
64 | |
65 | while (1) |
66 | ; |
67 | |
68 | return NOTIFY_DONE; |
69 | } |
70 | |
71 | static struct notifier_block brcmstb_restart_nb = { |
72 | .notifier_call = brcmstb_restart_handler, |
73 | .priority = 128, |
74 | }; |
75 | |
76 | static const struct reset_reg_mask reset_bits_40nm = { |
77 | .rst_src_en_mask = BIT(0), |
78 | .sw_mstr_rst_mask = BIT(0), |
79 | }; |
80 | |
81 | static const struct reset_reg_mask reset_bits_65nm = { |
82 | .rst_src_en_mask = BIT(3), |
83 | .sw_mstr_rst_mask = BIT(31), |
84 | }; |
85 | |
86 | static const struct of_device_id of_match[] = { |
87 | { .compatible = "brcm,brcmstb-reboot" , .data = &reset_bits_40nm }, |
88 | { .compatible = "brcm,bcm7038-reboot" , .data = &reset_bits_65nm }, |
89 | {}, |
90 | }; |
91 | |
92 | static int brcmstb_reboot_probe(struct platform_device *pdev) |
93 | { |
94 | int rc; |
95 | struct device_node *np = pdev->dev.of_node; |
96 | const struct of_device_id *of_id; |
97 | |
98 | of_id = of_match_node(matches: of_match, node: np); |
99 | if (!of_id) { |
100 | pr_err("failed to look up compatible string\n" ); |
101 | return -EINVAL; |
102 | } |
103 | reset_masks = of_id->data; |
104 | |
105 | regmap = syscon_regmap_lookup_by_phandle(np, property: "syscon" ); |
106 | if (IS_ERR(ptr: regmap)) { |
107 | pr_err("failed to get syscon phandle\n" ); |
108 | return -EINVAL; |
109 | } |
110 | |
111 | rc = of_property_read_u32_index(np, propname: "syscon" , RESET_SOURCE_ENABLE_REG, |
112 | out_value: &rst_src_en); |
113 | if (rc) { |
114 | pr_err("can't get rst_src_en offset (%d)\n" , rc); |
115 | return -EINVAL; |
116 | } |
117 | |
118 | rc = of_property_read_u32_index(np, propname: "syscon" , SW_MASTER_RESET_REG, |
119 | out_value: &sw_mstr_rst); |
120 | if (rc) { |
121 | pr_err("can't get sw_mstr_rst offset (%d)\n" , rc); |
122 | return -EINVAL; |
123 | } |
124 | |
125 | rc = register_restart_handler(&brcmstb_restart_nb); |
126 | if (rc) |
127 | dev_err(&pdev->dev, |
128 | "cannot register restart handler (err=%d)\n" , rc); |
129 | |
130 | return rc; |
131 | } |
132 | |
133 | static struct platform_driver brcmstb_reboot_driver = { |
134 | .probe = brcmstb_reboot_probe, |
135 | .driver = { |
136 | .name = "brcmstb-reboot" , |
137 | .of_match_table = of_match, |
138 | }, |
139 | }; |
140 | |
141 | static int __init brcmstb_reboot_init(void) |
142 | { |
143 | return platform_driver_probe(&brcmstb_reboot_driver, |
144 | brcmstb_reboot_probe); |
145 | } |
146 | subsys_initcall(brcmstb_reboot_init); |
147 | |