[linux-2.6-block.git] / drivers / reset / reset-brcmstb-rescal.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2018-2020 Broadcom */

#include <linux/device.h>
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>

#define BRCM_RESCAL_START	0x0
#define  BRCM_RESCAL_START_BIT	BIT(0)
#define BRCM_RESCAL_CTRL	0x4
#define BRCM_RESCAL_STATUS	0x8
#define  BRCM_RESCAL_STATUS_BIT	BIT(0)

struct brcm_rescal_reset {
	void __iomem *base;
	struct device *dev;
	struct reset_controller_dev rcdev;
};

static int brcm_rescal_reset_set(struct reset_controller_dev *rcdev,
				 unsigned long id)
{
	struct brcm_rescal_reset *data =
		container_of(rcdev, struct brcm_rescal_reset, rcdev);
	void __iomem *base = data->base;
	u32 reg;
	int ret;

	reg = readl(base + BRCM_RESCAL_START);
	writel(reg | BRCM_RESCAL_START_BIT, base + BRCM_RESCAL_START);
	reg = readl(base + BRCM_RESCAL_START);
	if (!(reg & BRCM_RESCAL_START_BIT)) {
		dev_err(data->dev, "failed to start SATA/PCIe rescal\n");
		return -EIO;
	}

	ret = readl_poll_timeout(base + BRCM_RESCAL_STATUS, reg,
				 !(reg & BRCM_RESCAL_STATUS_BIT), 100, 1000);
	if (ret) {
		dev_err(data->dev, "time out on SATA/PCIe rescal\n");
		return ret;
	}

	reg = readl(base + BRCM_RESCAL_START);
	writel(reg & ~BRCM_RESCAL_START_BIT, base + BRCM_RESCAL_START);

	dev_dbg(data->dev, "SATA/PCIe rescal success\n");

	return 0;
}

static int brcm_rescal_reset_xlate(struct reset_controller_dev *rcdev,
				   const struct of_phandle_args *reset_spec)
{
	/* This is needed if #reset-cells == 0. */
	return 0;
}

static const struct reset_control_ops brcm_rescal_reset_ops = {
	.reset = brcm_rescal_reset_set,
};

static int brcm_rescal_reset_probe(struct platform_device *pdev)
{
	struct brcm_rescal_reset *data;
	struct resource *res;

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	data->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(data->base))
		return PTR_ERR(data->base);

	data->rcdev.owner = THIS_MODULE;
	data->rcdev.nr_resets = 1;
	data->rcdev.ops = &brcm_rescal_reset_ops;
	data->rcdev.of_node = pdev->dev.of_node;
	data->rcdev.of_xlate = brcm_rescal_reset_xlate;
	data->dev = &pdev->dev;

	return devm_reset_controller_register(&pdev->dev, &data->rcdev);
}

static const struct of_device_id brcm_rescal_reset_of_match[] = {
	{ .compatible = "brcm,bcm7216-pcie-sata-rescal" },
	{ },
};
MODULE_DEVICE_TABLE(of, brcm_rescal_reset_of_match);

static struct platform_driver brcm_rescal_reset_driver = {
	.probe = brcm_rescal_reset_probe,
	.driver = {
		.name	= "brcm-rescal-reset",
		.of_match_table	= brcm_rescal_reset_of_match,
	}
};
module_platform_driver(brcm_rescal_reset_driver);

MODULE_AUTHOR("Broadcom");
MODULE_DESCRIPTION("Broadcom SATA/PCIe rescal reset controller");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
4cf176e5 JQ	1	// SPDX-License-Identifier: GPL-2.0
	2	/* Copyright (C) 2018-2020 Broadcom */
	3
	4	#include <linux/device.h>
	5	#include <linux/iopoll.h>
	6	#include <linux/module.h>
	7	#include <linux/of.h>
	8	#include <linux/platform_device.h>
	9	#include <linux/reset-controller.h>
	10
	11	#define BRCM_RESCAL_START 0x0
	12	#define BRCM_RESCAL_START_BIT BIT(0)
	13	#define BRCM_RESCAL_CTRL 0x4
	14	#define BRCM_RESCAL_STATUS 0x8
	15	#define BRCM_RESCAL_STATUS_BIT BIT(0)
	16
	17	struct brcm_rescal_reset {
	18	void __iomem *base;
	19	struct device *dev;
	20	struct reset_controller_dev rcdev;
	21	};
	22
	23	static int brcm_rescal_reset_set(struct reset_controller_dev *rcdev,
	24	unsigned long id)
	25	{
	26	struct brcm_rescal_reset *data =
	27	container_of(rcdev, struct brcm_rescal_reset, rcdev);
	28	void __iomem *base = data->base;
	29	u32 reg;
	30	int ret;
	31
	32	reg = readl(base + BRCM_RESCAL_START);
	33	writel(reg \| BRCM_RESCAL_START_BIT, base + BRCM_RESCAL_START);
	34	reg = readl(base + BRCM_RESCAL_START);
	35	if (!(reg & BRCM_RESCAL_START_BIT)) {
	36	dev_err(data->dev, "failed to start SATA/PCIe rescal\n");
	37	return -EIO;
	38	}
	39
	40	ret = readl_poll_timeout(base + BRCM_RESCAL_STATUS, reg,
	41	!(reg & BRCM_RESCAL_STATUS_BIT), 100, 1000);
	42	if (ret) {
	43	dev_err(data->dev, "time out on SATA/PCIe rescal\n");
	44	return ret;
	45	}
	46
	47	reg = readl(base + BRCM_RESCAL_START);
	48	writel(reg & ~BRCM_RESCAL_START_BIT, base + BRCM_RESCAL_START);
	49
	50	dev_dbg(data->dev, "SATA/PCIe rescal success\n");
	51
	52	return 0;
	53	}
	54
	55	static int brcm_rescal_reset_xlate(struct reset_controller_dev *rcdev,
	56	const struct of_phandle_args *reset_spec)
	57	{
	58	/* This is needed if #reset-cells == 0. */
	59	return 0;
	60	}
	61
	62	static const struct reset_control_ops brcm_rescal_reset_ops = {
	63	.reset = brcm_rescal_reset_set,
	64	};
65
66	static int brcm_rescal_reset_probe(struct platform_device *pdev)
67	{
68	struct brcm_rescal_reset *data;
69	struct resource *res;
70
71	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
72	if (!data)
73	return -ENOMEM;
74
75	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
76	data->base = devm_ioremap_resource(&pdev->dev, res);
77	if (IS_ERR(data->base))
78	return PTR_ERR(data->base);
79
80	data->rcdev.owner = THIS_MODULE;
81	data->rcdev.nr_resets = 1;
82	data->rcdev.ops = &brcm_rescal_reset_ops;
83	data->rcdev.of_node = pdev->dev.of_node;
84	data->rcdev.of_xlate = brcm_rescal_reset_xlate;
85	data->dev = &pdev->dev;
86
87	return devm_reset_controller_register(&pdev->dev, &data->rcdev);
88	}
89
90	static const struct of_device_id brcm_rescal_reset_of_match[] = {
91	{ .compatible = "brcm,bcm7216-pcie-sata-rescal" },
92	{ },
93	};
94	MODULE_DEVICE_TABLE(of, brcm_rescal_reset_of_match);
95
96	static struct platform_driver brcm_rescal_reset_driver = {
97	.probe = brcm_rescal_reset_probe,
98	.driver = {
99	.name = "brcm-rescal-reset",
100	.of_match_table = brcm_rescal_reset_of_match,
101	}
102	};
103	module_platform_driver(brcm_rescal_reset_driver);
104
105	MODULE_AUTHOR("Broadcom");
106	MODULE_DESCRIPTION("Broadcom SATA/PCIe rescal reset controller");
107	MODULE_LICENSE("GPL v2");