1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
4 * Author(s): Patrice Chotard, <patrice.chotard@foss.st.com> for STMicroelectronics.
5 */
6
7 #include <common.h>
8 #include <dm.h>
9 #include <regmap.h>
10 #include <syscon.h>
11 #include <sysreset.h>
12 #include <asm/global_data.h>
13 #include <asm/io.h>
14 #include <linux/bitops.h>
15
16 DECLARE_GLOBAL_DATA_PTR;
17
18 struct sti_sysreset_priv {
19 phys_addr_t base;
20 };
21
sti_sysreset_request(struct udevice * dev,enum sysreset_t type)22 static int sti_sysreset_request(struct udevice *dev, enum sysreset_t type)
23 {
24 struct sti_sysreset_priv *priv = dev_get_priv(dev);
25
26 generic_clear_bit(0, (void __iomem *)priv->base);
27
28 return -EINPROGRESS;
29 }
30
sti_sysreset_probe(struct udevice * dev)31 static int sti_sysreset_probe(struct udevice *dev)
32 {
33 struct sti_sysreset_priv *priv = dev_get_priv(dev);
34 struct udevice *syscon;
35 struct regmap *regmap;
36 struct fdtdec_phandle_args syscfg_phandle;
37 int ret;
38
39 /* get corresponding syscon phandle */
40 ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev_of_offset(dev),
41 "st,syscfg", NULL, 0, 0,
42 &syscfg_phandle);
43 if (ret < 0) {
44 pr_err("Can't get syscfg phandle: %d\n", ret);
45 return ret;
46 }
47
48 ret = uclass_get_device_by_of_offset(UCLASS_SYSCON,
49 syscfg_phandle.node,
50 &syscon);
51 if (ret) {
52 pr_err("%s: uclass_get_device_by_of_offset failed: %d\n",
53 __func__, ret);
54 return ret;
55 }
56
57 regmap = syscon_get_regmap(syscon);
58 if (!regmap) {
59 pr_err("unable to get regmap for %s\n", syscon->name);
60 return -ENODEV;
61 }
62
63 priv->base = regmap->ranges[0].start;
64
65 return 0;
66 }
67
68 static struct sysreset_ops sti_sysreset = {
69 .request = sti_sysreset_request,
70 };
71
72 static const struct udevice_id sti_sysreset_ids[] = {
73 { .compatible = "st,stih407-restart" },
74 { }
75 };
76
77 U_BOOT_DRIVER(sysreset_sti) = {
78 .name = "sysreset_sti",
79 .id = UCLASS_SYSRESET,
80 .ops = &sti_sysreset,
81 .probe = sti_sysreset_probe,
82 .of_match = sti_sysreset_ids,
83 .priv_auto = sizeof(struct sti_sysreset_priv),
84 };
85