xref: /openbmc/linux/drivers/ata/ahci_st.c (revision e6c81cce)
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 DRV_NAME  "st_ahci"
27 
28 #define ST_AHCI_OOBR			0xbc
29 #define ST_AHCI_OOBR_WE			BIT(31)
30 #define ST_AHCI_OOBR_CWMIN_SHIFT	24
31 #define ST_AHCI_OOBR_CWMAX_SHIFT	16
32 #define ST_AHCI_OOBR_CIMIN_SHIFT	8
33 #define ST_AHCI_OOBR_CIMAX_SHIFT	0
34 
35 struct st_ahci_drv_data {
36 	struct platform_device *ahci;
37 	struct reset_control *pwr;
38 	struct reset_control *sw_rst;
39 	struct reset_control *pwr_rst;
40 	struct ahci_host_priv *hpriv;
41 };
42 
43 static void st_ahci_configure_oob(void __iomem *mmio)
44 {
45 	unsigned long old_val, new_val;
46 
47 	new_val = (0x02 << ST_AHCI_OOBR_CWMIN_SHIFT) |
48 		  (0x04 << ST_AHCI_OOBR_CWMAX_SHIFT) |
49 		  (0x08 << ST_AHCI_OOBR_CIMIN_SHIFT) |
50 		  (0x0C << ST_AHCI_OOBR_CIMAX_SHIFT);
51 
52 	old_val = readl(mmio + ST_AHCI_OOBR);
53 	writel(old_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
54 	writel(new_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
55 	writel(new_val, mmio + ST_AHCI_OOBR);
56 }
57 
58 static int st_ahci_deassert_resets(struct device *dev)
59 {
60 	struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
61 	int err;
62 
63 	if (drv_data->pwr) {
64 		err = reset_control_deassert(drv_data->pwr);
65 		if (err) {
66 			dev_err(dev, "unable to bring out of pwrdwn\n");
67 			return err;
68 		}
69 	}
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 struct scsi_host_template ahci_platform_sht = {
144 	AHCI_SHT(DRV_NAME),
145 };
146 
147 static int st_ahci_probe(struct platform_device *pdev)
148 {
149 	struct st_ahci_drv_data *drv_data;
150 	struct ahci_host_priv *hpriv;
151 	int err;
152 
153 	drv_data = devm_kzalloc(&pdev->dev, sizeof(*drv_data), GFP_KERNEL);
154 	if (!drv_data)
155 		return -ENOMEM;
156 
157 	platform_set_drvdata(pdev, drv_data);
158 
159 	hpriv = ahci_platform_get_resources(pdev);
160 	if (IS_ERR(hpriv))
161 		return PTR_ERR(hpriv);
162 
163 	drv_data->hpriv = hpriv;
164 
165 	err = st_ahci_probe_resets(pdev);
166 	if (err)
167 		return err;
168 
169 	err = ahci_platform_enable_resources(hpriv);
170 	if (err)
171 		return err;
172 
173 	st_ahci_configure_oob(drv_data->hpriv->mmio);
174 
175 	err = ahci_platform_init_host(pdev, hpriv, &st_ahci_port_info,
176 				      &ahci_platform_sht);
177 	if (err) {
178 		ahci_platform_disable_resources(hpriv);
179 		return err;
180 	}
181 
182 	return 0;
183 }
184 
185 #ifdef CONFIG_PM_SLEEP
186 static int st_ahci_suspend(struct device *dev)
187 {
188 	struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
189 	struct ahci_host_priv *hpriv = drv_data->hpriv;
190 	int err;
191 
192 	err = ahci_platform_suspend_host(dev);
193 	if (err)
194 		return err;
195 
196 	if (drv_data->pwr) {
197 		err = reset_control_assert(drv_data->pwr);
198 		if (err) {
199 			dev_err(dev, "unable to pwrdwn");
200 			return err;
201 		}
202 	}
203 
204 	ahci_platform_disable_resources(hpriv);
205 
206 	return 0;
207 }
208 
209 static int st_ahci_resume(struct device *dev)
210 {
211 	struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
212 	struct ahci_host_priv *hpriv = drv_data->hpriv;
213 	int err;
214 
215 	err = ahci_platform_enable_resources(hpriv);
216 	if (err)
217 		return err;
218 
219 	err = st_ahci_deassert_resets(dev);
220 	if (err) {
221 		ahci_platform_disable_resources(hpriv);
222 		return err;
223 	}
224 
225 	st_ahci_configure_oob(drv_data->hpriv->mmio);
226 
227 	return ahci_platform_resume_host(dev);
228 }
229 #endif
230 
231 static SIMPLE_DEV_PM_OPS(st_ahci_pm_ops, st_ahci_suspend, st_ahci_resume);
232 
233 static const struct of_device_id st_ahci_match[] = {
234 	{ .compatible = "st,ahci", },
235 	{},
236 };
237 MODULE_DEVICE_TABLE(of, st_ahci_match);
238 
239 static struct platform_driver st_ahci_driver = {
240 	.driver = {
241 		.name = DRV_NAME,
242 		.pm = &st_ahci_pm_ops,
243 		.of_match_table = of_match_ptr(st_ahci_match),
244 	},
245 	.probe = st_ahci_probe,
246 	.remove = ata_platform_remove_one,
247 };
248 module_platform_driver(st_ahci_driver);
249 
250 MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue@st.com>");
251 MODULE_AUTHOR("Francesco Virlinzi <francesco.virlinzi@st.com>");
252 MODULE_DESCRIPTION("STMicroelectronics SATA AHCI Driver");
253 MODULE_LICENSE("GPL v2");
254