[thirdparty/u-boot.git] / drivers / reset / reset-sifive.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2020 Sifive, Inc.
 * Author: Sagar Kadam <sagar.kadam@sifive.com>
 */

#include <common.h>
#include <dm.h>
#include <reset-uclass.h>
#include <asm/io.h>
#include <dm/device_compat.h>
#include <dm/device-internal.h>
#include <dm/lists.h>
#include <linux/bitops.h>

#define PRCI_RESETREG_OFFSET 0x28

struct sifive_reset_priv {
	void *base;
	/* number of reset signals */
	int nr_reset;
};

static int sifive_rst_trigger(struct reset_ctl *rst, bool level)
{
	struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
	int id = rst->id;
	int regval = readl(priv->base + PRCI_RESETREG_OFFSET);

	/* Derive bitposition from rst id */
	if (level)
		/* Reset deassert */
		regval |= BIT(id);
	else
		/* Reset assert */
		regval &= ~BIT(id);

	writel(regval, priv->base + PRCI_RESETREG_OFFSET);

	return 0;
}

static int sifive_reset_assert(struct reset_ctl *rst)
{
	return sifive_rst_trigger(rst, false);
}

static int sifive_reset_deassert(struct reset_ctl *rst)
{
	return sifive_rst_trigger(rst, true);
}

static int sifive_reset_request(struct reset_ctl *rst)
{
	struct sifive_reset_priv *priv = dev_get_priv(rst->dev);

	debug("%s(rst=%p) (dev=%p, id=%lu) (nr_reset=%d)\n", __func__,
	      rst, rst->dev, rst->id, priv->nr_reset);

	if (rst->id > priv->nr_reset)
		return -EINVAL;

	return 0;
}

static int sifive_reset_probe(struct udevice *dev)
{
	struct sifive_reset_priv *priv = dev_get_priv(dev);

	priv->base = dev_remap_addr(dev);
	if (!priv->base)
		return -ENOMEM;

	return 0;
}

int sifive_reset_bind(struct udevice *dev, ulong count)
{
	struct udevice *rst_dev;
	struct sifive_reset_priv *priv;
	int ret;

	ret = device_bind_driver_to_node(dev, "sifive-reset", "reset",
					 dev_ofnode(dev), &rst_dev);
	if (ret) {
		dev_err(dev, "failed to bind sifive_reset driver (ret=%d)\n", ret);
		return ret;
	}
	priv = malloc(sizeof(struct sifive_reset_priv));
	priv->nr_reset = count;
	dev_set_priv(rst_dev, priv);

	return 0;
}

const struct reset_ops sifive_reset_ops = {
	.request = sifive_reset_request,
	.rst_assert = sifive_reset_assert,
	.rst_deassert = sifive_reset_deassert,
};

U_BOOT_DRIVER(sifive_reset) = {
	.name		= "sifive-reset",
	.id		= UCLASS_RESET,
	.ops		= &sifive_reset_ops,
	.probe		= sifive_reset_probe,
	.priv_auto	= sizeof(struct sifive_reset_priv),
};
Commit	Line	Data
d04a4642 SSK	1	// SPDX-License-Identifier: GPL-2.0+
	2	/*
	3	* Copyright (C) 2020 Sifive, Inc.
	4	* Author: Sagar Kadam <sagar.kadam@sifive.com>
	5	*/
	6
d678a59d	7	#include <common.h>
d04a4642 SSK	8	#include <dm.h>
	9	#include <reset-uclass.h>
	10	#include <asm/io.h>
	11	#include <dm/device_compat.h>
0fd3d911	12	#include <dm/device-internal.h>
d04a4642 SSK	13	#include <dm/lists.h>
	14	#include <linux/bitops.h>
	15
	16	#define PRCI_RESETREG_OFFSET 0x28
	17
	18	struct sifive_reset_priv {
	19	void *base;
	20	/* number of reset signals */
	21	int nr_reset;
	22	};
	23
	24	static int sifive_rst_trigger(struct reset_ctl *rst, bool level)
	25	{
	26	struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
	27	int id = rst->id;
	28	int regval = readl(priv->base + PRCI_RESETREG_OFFSET);
	29
	30	/* Derive bitposition from rst id */
	31	if (level)
	32	/* Reset deassert */
	33	regval \|= BIT(id);
	34	else
	35	/* Reset assert */
	36	regval &= ~BIT(id);
	37
	38	writel(regval, priv->base + PRCI_RESETREG_OFFSET);
	39
	40	return 0;
	41	}
	42
	43	static int sifive_reset_assert(struct reset_ctl *rst)
	44	{
	45	return sifive_rst_trigger(rst, false);
	46	}
	47
	48	static int sifive_reset_deassert(struct reset_ctl *rst)
	49	{
	50	return sifive_rst_trigger(rst, true);
	51	}
	52
	53	static int sifive_reset_request(struct reset_ctl *rst)
	54	{
	55	struct sifive_reset_priv *priv = dev_get_priv(rst->dev);
	56
	57	debug("%s(rst=%p) (dev=%p, id=%lu) (nr_reset=%d)\n", __func__,
	58	rst, rst->dev, rst->id, priv->nr_reset);
	59
	60	if (rst->id > priv->nr_reset)
	61	return -EINVAL;
	62
	63	return 0;
	64	}
	65
d04a4642 SSK	66	static int sifive_reset_probe(struct udevice *dev)
	67	{
	68	struct sifive_reset_priv *priv = dev_get_priv(dev);
	69
	70	priv->base = dev_remap_addr(dev);
	71	if (!priv->base)
	72	return -ENOMEM;
	73
	74	return 0;
	75	}
	76
	77	int sifive_reset_bind(struct udevice *dev, ulong count)
	78	{
	79	struct udevice *rst_dev;
	80	struct sifive_reset_priv *priv;
	81	int ret;
	82
	83	ret = device_bind_driver_to_node(dev, "sifive-reset", "reset",
	84	dev_ofnode(dev), &rst_dev);
	85	if (ret) {
	86	dev_err(dev, "failed to bind sifive_reset driver (ret=%d)\n", ret);
	87	return ret;
	88	}
	89	priv = malloc(sizeof(struct sifive_reset_priv));
	90	priv->nr_reset = count;
0fd3d911	91	dev_set_priv(rst_dev, priv);
d04a4642 SSK	92
	93	return 0;
	94	}
	95
	96	const struct reset_ops sifive_reset_ops = {
	97	.request = sifive_reset_request,
d04a4642 SSK	98	.rst_assert = sifive_reset_assert,
	99	.rst_deassert = sifive_reset_deassert,
	100	};
	101
	102	U_BOOT_DRIVER(sifive_reset) = {
	103	.name = "sifive-reset",
	104	.id = UCLASS_RESET,
	105	.ops = &sifive_reset_ops,
	106	.probe = sifive_reset_probe,
41575d8e	107	.priv_auto = sizeof(struct sifive_reset_priv),
d04a4642	108	};