1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
4 *
5 * Derived from linux/arch/mips/bcm63xx/reset.c:
6 * Copyright (C) 2012 Jonas Gorski <jonas.gorski@gmail.com>
7 */
8
9 #include <dm.h>
10 #include <errno.h>
11 #include <log.h>
12 #include <malloc.h>
13 #include <reset-uclass.h>
14 #include <asm/io.h>
15 #include <linux/bitops.h>
16 #include <linux/delay.h>
17
18 #define MAX_RESETS 32
19
20 struct bcm6345_reset_priv {
21 void __iomem *regs;
22 };
23
bcm6345_reset_assert(struct reset_ctl * rst)24 static int bcm6345_reset_assert(struct reset_ctl *rst)
25 {
26 struct bcm6345_reset_priv *priv = dev_get_priv(rst->dev);
27
28 clrbits_be32(priv->regs, BIT(rst->id));
29 mdelay(20);
30
31 return 0;
32 }
33
bcm6345_reset_deassert(struct reset_ctl * rst)34 static int bcm6345_reset_deassert(struct reset_ctl *rst)
35 {
36 struct bcm6345_reset_priv *priv = dev_get_priv(rst->dev);
37
38 setbits_be32(priv->regs, BIT(rst->id));
39 mdelay(20);
40
41 return 0;
42 }
43
bcm6345_reset_request(struct reset_ctl * rst)44 static int bcm6345_reset_request(struct reset_ctl *rst)
45 {
46 if (rst->id >= MAX_RESETS)
47 return -EINVAL;
48
49 return bcm6345_reset_assert(rst);
50 }
51
52 struct reset_ops bcm6345_reset_reset_ops = {
53 .request = bcm6345_reset_request,
54 .rst_assert = bcm6345_reset_assert,
55 .rst_deassert = bcm6345_reset_deassert,
56 };
57
58 static const struct udevice_id bcm6345_reset_ids[] = {
59 { .compatible = "brcm,bcm6345-reset" },
60 { /* sentinel */ }
61 };
62
bcm6345_reset_probe(struct udevice * dev)63 static int bcm6345_reset_probe(struct udevice *dev)
64 {
65 struct bcm6345_reset_priv *priv = dev_get_priv(dev);
66
67 priv->regs = dev_remap_addr(dev);
68 if (!priv->regs)
69 return -EINVAL;
70
71 return 0;
72 }
73
74 U_BOOT_DRIVER(bcm6345_reset) = {
75 .name = "bcm6345-reset",
76 .id = UCLASS_RESET,
77 .of_match = bcm6345_reset_ids,
78 .ops = &bcm6345_reset_reset_ops,
79 .probe = bcm6345_reset_probe,
80 .priv_auto = sizeof(struct bcm6345_reset_priv),
81 };
82