1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (C) 2020 Sifive, Inc.
4 * Author: Sagar Kadam <sagar.kadam@sifive.com>
9 #include <reset-uclass.h>
11 #include <dm/device_compat.h>
12 #include <dm/device-internal.h>
14 #include <linux/bitops.h>
16 #define PRCI_RESETREG_OFFSET 0x28
18 struct sifive_reset_priv {
20 /* number of reset signals */
24 static int sifive_rst_trigger(struct reset_ctl *rst, bool level)
26 struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
28 int regval = readl(priv->base + PRCI_RESETREG_OFFSET);
30 /* Derive bitposition from rst id */
38 writel(regval, priv->base + PRCI_RESETREG_OFFSET);
43 static int sifive_reset_assert(struct reset_ctl *rst)
45 return sifive_rst_trigger(rst, false);
48 static int sifive_reset_deassert(struct reset_ctl *rst)
50 return sifive_rst_trigger(rst, true);
53 static int sifive_reset_request(struct reset_ctl *rst)
55 struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
57 debug("%s(rst=%p) (dev=%p, id=%lu) (nr_reset=%d)\n", __func__,
58 rst, rst->dev, rst->id, priv->nr_reset);
60 if (rst->id > priv->nr_reset)
66 static int sifive_reset_free(struct reset_ctl *rst)
68 struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
70 debug("%s(rst=%p) (dev=%p, id=%lu) (nr_reset=%d)\n", __func__,
71 rst, rst->dev, rst->id, priv->nr_reset);
76 static int sifive_reset_probe(struct udevice *dev)
78 struct sifive_reset_priv *priv = dev_get_priv(dev);
80 priv->base = dev_remap_addr(dev);
87 int sifive_reset_bind(struct udevice *dev, ulong count)
89 struct udevice *rst_dev;
90 struct sifive_reset_priv *priv;
93 ret = device_bind_driver_to_node(dev, "sifive-reset", "reset",
94 dev_ofnode(dev), &rst_dev);
96 dev_err(dev, "failed to bind sifive_reset driver (ret=%d)\n", ret);
99 priv = malloc(sizeof(struct sifive_reset_priv));
100 priv->nr_reset = count;
101 dev_set_priv(rst_dev, priv);
106 const struct reset_ops sifive_reset_ops = {
107 .request = sifive_reset_request,
108 .rfree = sifive_reset_free,
109 .rst_assert = sifive_reset_assert,
110 .rst_deassert = sifive_reset_deassert,
113 U_BOOT_DRIVER(sifive_reset) = {
114 .name = "sifive-reset",
116 .ops = &sifive_reset_ops,
117 .probe = sifive_reset_probe,
118 .priv_auto = sizeof(struct sifive_reset_priv),