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git01.mediatek.com / filogic / uboot / ff184fe9ab195cd9fdb7d72774872bfdbf8669c1 / . / drivers / reset / reset-sifive.c
blob: 527757f8533da841620e5a4d0725db26db39e19b [file] [log] [blame]
Sagar Shrikant Kadame1ff6eb2020-07-29 02:36:13 -0700[diff] [blame]1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2020 Sifive, Inc.
4 * Author: Sagar Kadam <sagar.kadam@sifive.com>
5 */
6
7#include <common.h>
8#include <dm.h>
9#include <reset-uclass.h>
10#include <asm/io.h>
11#include <dm/device_compat.h>
12#include <dm/lists.h>
13#include <linux/bitops.h>
14
15#define PRCI_RESETREG_OFFSET 0x28
16
17struct sifive_reset_priv {
18 void *base;
19 /* number of reset signals */
20 int nr_reset;
21};
22
23static int sifive_rst_trigger(struct reset_ctl *rst, bool level)
24{
25 struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
26 int id = rst->id;
27 int regval = readl(priv->base + PRCI_RESETREG_OFFSET);
28
29 /* Derive bitposition from rst id */
30 if (level)
31 /* Reset deassert */
32 regval |= BIT(id);
33 else
34 /* Reset assert */
35 regval &= ~BIT(id);
36
37 writel(regval, priv->base + PRCI_RESETREG_OFFSET);
38
39 return 0;
40}
41
42static int sifive_reset_assert(struct reset_ctl *rst)
43{
44 return sifive_rst_trigger(rst, false);
45}
46
47static int sifive_reset_deassert(struct reset_ctl *rst)
48{
49 return sifive_rst_trigger(rst, true);
50}
51
52static int sifive_reset_request(struct reset_ctl *rst)
53{
54 struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
55
56 debug("%s(rst=%p) (dev=%p, id=%lu) (nr_reset=%d)\n", __func__,
57 rst, rst->dev, rst->id, priv->nr_reset);
58
59 if (rst->id > priv->nr_reset)
60 return -EINVAL;
61
62 return 0;
63}
64
65static int sifive_reset_free(struct reset_ctl *rst)
66{
67 struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
68
69 debug("%s(rst=%p) (dev=%p, id=%lu) (nr_reset=%d)\n", __func__,
70 rst, rst->dev, rst->id, priv->nr_reset);
71
72 return 0;
73}
74
75static int sifive_reset_probe(struct udevice *dev)
76{
77 struct sifive_reset_priv *priv = dev_get_priv(dev);
78
79 priv->base = dev_remap_addr(dev);
80 if (!priv->base)
81 return -ENOMEM;
82
83 return 0;
84}
85
86int sifive_reset_bind(struct udevice *dev, ulong count)
87{
88 struct udevice *rst_dev;
89 struct sifive_reset_priv *priv;
90 int ret;
91
92 ret = device_bind_driver_to_node(dev, "sifive-reset", "reset",
93 dev_ofnode(dev), &rst_dev);
94 if (ret) {
95 dev_err(dev, "failed to bind sifive_reset driver (ret=%d)\n", ret);
96 return ret;
97 }
98 priv = malloc(sizeof(struct sifive_reset_priv));
99 priv->nr_reset = count;
100 rst_dev->priv = priv;
101
102 return 0;
103}
104
105const struct reset_ops sifive_reset_ops = {
106 .request = sifive_reset_request,
107 .rfree = sifive_reset_free,
108 .rst_assert = sifive_reset_assert,
109 .rst_deassert = sifive_reset_deassert,
110};
111
112U_BOOT_DRIVER(sifive_reset) = {
113 .name = "sifive-reset",
114 .id = UCLASS_RESET,
115 .ops = &sifive_reset_ops,
116 .probe = sifive_reset_probe,
117 .priv_auto_alloc_size = sizeof(struct sifive_reset_priv),
118};