xref: /openbmc/linux/drivers/ata/ahci_st.c (revision 455f9726)
1 /*
2  * Copyright (C) 2012 STMicroelectronics Limited
3  *
4  * Authors: Francesco Virlinzi <francesco.virlinzi@st.com>
5  *	    Alexandre Torgue <alexandre.torgue@st.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/export.h>
15 #include <linux/platform_device.h>
16 #include <linux/clk.h>
17 #include <linux/of.h>
18 #include <linux/ahci_platform.h>
19 #include <linux/libata.h>
20 #include <linux/reset.h>
21 #include <linux/io.h>
22 #include <linux/dma-mapping.h>
23 
24 #include "ahci.h"
25 
26 #define ST_AHCI_OOBR			0xbc
27 #define ST_AHCI_OOBR_WE			BIT(31)
28 #define ST_AHCI_OOBR_CWMIN_SHIFT	24
29 #define ST_AHCI_OOBR_CWMAX_SHIFT	16
30 #define ST_AHCI_OOBR_CIMIN_SHIFT	8
31 #define ST_AHCI_OOBR_CIMAX_SHIFT	0
32 
33 struct st_ahci_drv_data {
34 	struct platform_device *ahci;
35 	struct reset_control *pwr;
36 	struct reset_control *sw_rst;
37 	struct reset_control *pwr_rst;
38 	struct ahci_host_priv *hpriv;
39 };
40 
41 static void st_ahci_configure_oob(void __iomem *mmio)
42 {
43 	unsigned long old_val, new_val;
44 
45 	new_val = (0x02 << ST_AHCI_OOBR_CWMIN_SHIFT) |
46 		  (0x04 << ST_AHCI_OOBR_CWMAX_SHIFT) |
47 		  (0x08 << ST_AHCI_OOBR_CIMIN_SHIFT) |
48 		  (0x0C << ST_AHCI_OOBR_CIMAX_SHIFT);
49 
50 	old_val = readl(mmio + ST_AHCI_OOBR);
51 	writel(old_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
52 	writel(new_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
53 	writel(new_val, mmio + ST_AHCI_OOBR);
54 }
55 
56 static int st_ahci_deassert_resets(struct device *dev)
57 {
58 	struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
59 	int err;
60 
61 	if (drv_data->pwr) {
62 		err = reset_control_deassert(drv_data->pwr);
63 		if (err) {
64 			dev_err(dev, "unable to bring out of pwrdwn\n");
65 			return err;
66 		}
67 	}
68 
69 	st_ahci_configure_oob(drv_data->hpriv->mmio);
70 
71 	if (drv_data->sw_rst) {
72 		err = reset_control_deassert(drv_data->sw_rst);
73 		if (err) {
74 			dev_err(dev, "unable to bring out of sw-rst\n");
75 			return err;
76 		}
77 	}
78 
79 	if (drv_data->pwr_rst) {
80 		err = reset_control_deassert(drv_data->pwr_rst);
81 		if (err) {
82 			dev_err(dev, "unable to bring out of pwr-rst\n");
83 			return err;
84 		}
85 	}
86 
87 	return 0;
88 }
89 
90 static void st_ahci_host_stop(struct ata_host *host)
91 {
92 	struct ahci_host_priv *hpriv = host->private_data;
93 	struct device *dev = host->dev;
94 	struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
95 	int err;
96 
97 	if (drv_data->pwr) {
98 		err = reset_control_assert(drv_data->pwr);
99 		if (err)
100 			dev_err(dev, "unable to pwrdwn\n");
101 	}
102 
103 	ahci_platform_disable_resources(hpriv);
104 }
105 
106 static int st_ahci_probe_resets(struct platform_device *pdev)
107 {
108 	struct st_ahci_drv_data *drv_data = platform_get_drvdata(pdev);
109 
110 	drv_data->pwr = devm_reset_control_get(&pdev->dev, "pwr-dwn");
111 	if (IS_ERR(drv_data->pwr)) {
112 		dev_info(&pdev->dev, "power reset control not defined\n");
113 		drv_data->pwr = NULL;
114 	}
115 
116 	drv_data->sw_rst = devm_reset_control_get(&pdev->dev, "sw-rst");
117 	if (IS_ERR(drv_data->sw_rst)) {
118 		dev_info(&pdev->dev, "soft reset control not defined\n");
119 		drv_data->sw_rst = NULL;
120 	}
121 
122 	drv_data->pwr_rst = devm_reset_control_get(&pdev->dev, "pwr-rst");
123 	if (IS_ERR(drv_data->pwr_rst)) {
124 		dev_dbg(&pdev->dev, "power soft reset control not defined\n");
125 		drv_data->pwr_rst = NULL;
126 	}
127 
128 	return st_ahci_deassert_resets(&pdev->dev);
129 }
130 
131 static struct ata_port_operations st_ahci_port_ops = {
132 	.inherits	= &ahci_platform_ops,
133 	.host_stop	= st_ahci_host_stop,
134 };
135 
136 static const struct ata_port_info st_ahci_port_info = {
137 	.flags          = AHCI_FLAG_COMMON,
138 	.pio_mask       = ATA_PIO4,
139 	.udma_mask      = ATA_UDMA6,
140 	.port_ops       = &st_ahci_port_ops,
141 };
142 
143 static int st_ahci_probe(struct platform_device *pdev)
144 {
145 	struct st_ahci_drv_data *drv_data;
146 	struct ahci_host_priv *hpriv;
147 	int err;
148 
149 	drv_data = devm_kzalloc(&pdev->dev, sizeof(*drv_data), GFP_KERNEL);
150 	if (!drv_data)
151 		return -ENOMEM;
152 
153 	platform_set_drvdata(pdev, drv_data);
154 
155 	hpriv = ahci_platform_get_resources(pdev);
156 	if (IS_ERR(hpriv))
157 		return PTR_ERR(hpriv);
158 
159 	drv_data->hpriv = hpriv;
160 
161 	err = st_ahci_probe_resets(pdev);
162 	if (err)
163 		return err;
164 
165 	err = ahci_platform_enable_resources(hpriv);
166 	if (err)
167 		return err;
168 
169 	err = ahci_platform_init_host(pdev, hpriv, &st_ahci_port_info);
170 	if (err) {
171 		ahci_platform_disable_resources(hpriv);
172 		return err;
173 	}
174 
175 	return 0;
176 }
177 
178 #ifdef CONFIG_PM_SLEEP
179 static int st_ahci_suspend(struct device *dev)
180 {
181 	struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
182 	struct ahci_host_priv *hpriv = drv_data->hpriv;
183 	int err;
184 
185 	err = ahci_platform_suspend_host(dev);
186 	if (err)
187 		return err;
188 
189 	if (drv_data->pwr) {
190 		err = reset_control_assert(drv_data->pwr);
191 		if (err) {
192 			dev_err(dev, "unable to pwrdwn");
193 			return err;
194 		}
195 	}
196 
197 	ahci_platform_disable_resources(hpriv);
198 
199 	return 0;
200 }
201 
202 static int st_ahci_resume(struct device *dev)
203 {
204 	struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
205 	struct ahci_host_priv *hpriv = drv_data->hpriv;
206 	int err;
207 
208 	err = ahci_platform_enable_resources(hpriv);
209 	if (err)
210 		return err;
211 
212 	err = st_ahci_deassert_resets(dev);
213 	if (err) {
214 		ahci_platform_disable_resources(hpriv);
215 		return err;
216 	}
217 
218 	return ahci_platform_resume_host(dev);
219 }
220 #endif
221 
222 static SIMPLE_DEV_PM_OPS(st_ahci_pm_ops, st_ahci_suspend, st_ahci_resume);
223 
224 static const struct of_device_id st_ahci_match[] = {
225 	{ .compatible = "st,ahci", },
226 	{},
227 };
228 MODULE_DEVICE_TABLE(of, st_ahci_match);
229 
230 static struct platform_driver st_ahci_driver = {
231 	.driver = {
232 		.name = "st_ahci",
233 		.owner = THIS_MODULE,
234 		.pm = &st_ahci_pm_ops,
235 		.of_match_table = of_match_ptr(st_ahci_match),
236 	},
237 	.probe = st_ahci_probe,
238 	.remove = ata_platform_remove_one,
239 };
240 module_platform_driver(st_ahci_driver);
241 
242 MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue@st.com>");
243 MODULE_AUTHOR("Francesco Virlinzi <francesco.virlinzi@st.com>");
244 MODULE_DESCRIPTION("STMicroelectronics SATA AHCI Driver");
245 MODULE_LICENSE("GPL v2");
246