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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
17struct brcm_rescal_reset {
18 void __iomem *base;
19 struct device *dev;
20 struct reset_controller_dev rcdev;
21};
22
23static 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
55static 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
62static const struct reset_control_ops brcm_rescal_reset_ops = {
63 .reset = brcm_rescal_reset_set,
64};
65
66static int brcm_rescal_reset_probe(struct platform_device *pdev)
67{
68 struct brcm_rescal_reset *data;
69
70 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
71 if (!data)
72 return -ENOMEM;
73
74 data->base = devm_platform_ioremap_resource(pdev, 0);
75 if (IS_ERR(data->base))
76 return PTR_ERR(data->base);
77
78 data->rcdev.owner = THIS_MODULE;
79 data->rcdev.nr_resets = 1;
80 data->rcdev.ops = &brcm_rescal_reset_ops;
81 data->rcdev.of_node = pdev->dev.of_node;
82 data->rcdev.of_xlate = brcm_rescal_reset_xlate;
83 data->dev = &pdev->dev;
84
85 return devm_reset_controller_register(&pdev->dev, &data->rcdev);
86}
87
88static const struct of_device_id brcm_rescal_reset_of_match[] = {
89 { .compatible = "brcm,bcm7216-pcie-sata-rescal" },
90 { },
91};
92MODULE_DEVICE_TABLE(of, brcm_rescal_reset_of_match);
93
94static struct platform_driver brcm_rescal_reset_driver = {
95 .probe = brcm_rescal_reset_probe,
96 .driver = {
97 .name = "brcm-rescal-reset",
98 .of_match_table = brcm_rescal_reset_of_match,
99 }
100};
101module_platform_driver(brcm_rescal_reset_driver);
102
103MODULE_AUTHOR("Broadcom");
104MODULE_DESCRIPTION("Broadcom SATA/PCIe rescal reset controller");
105MODULE_LICENSE("GPL v2");
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
17struct brcm_rescal_reset {
18 void __iomem *base;
19 struct device *dev;
20 struct reset_controller_dev rcdev;
21};
22
23static 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
55static 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
62static const struct reset_control_ops brcm_rescal_reset_ops = {
63 .reset = brcm_rescal_reset_set,
64};
65
66static 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
90static const struct of_device_id brcm_rescal_reset_of_match[] = {
91 { .compatible = "brcm,bcm7216-pcie-sata-rescal" },
92 { },
93};
94MODULE_DEVICE_TABLE(of, brcm_rescal_reset_of_match);
95
96static 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};
103module_platform_driver(brcm_rescal_reset_driver);
104
105MODULE_AUTHOR("Broadcom");
106MODULE_DESCRIPTION("Broadcom SATA/PCIe rescal reset controller");
107MODULE_LICENSE("GPL v2");