xref: /openbmc/linux/drivers/ata/ahci_st.c (revision 6dfcd296)
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 };
41 
42 static void st_ahci_configure_oob(void __iomem *mmio)
43 {
44 	unsigned long old_val, new_val;
45 
46 	new_val = (0x02 << ST_AHCI_OOBR_CWMIN_SHIFT) |
47 		  (0x04 << ST_AHCI_OOBR_CWMAX_SHIFT) |
48 		  (0x08 << ST_AHCI_OOBR_CIMIN_SHIFT) |
49 		  (0x0C << ST_AHCI_OOBR_CIMAX_SHIFT);
50 
51 	old_val = readl(mmio + ST_AHCI_OOBR);
52 	writel(old_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
53 	writel(new_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
54 	writel(new_val, mmio + ST_AHCI_OOBR);
55 }
56 
57 static int st_ahci_deassert_resets(struct ahci_host_priv *hpriv,
58 				struct device *dev)
59 {
60 	struct st_ahci_drv_data *drv_data = hpriv->plat_data;
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 st_ahci_drv_data *drv_data = hpriv->plat_data;
94 	struct device *dev = host->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 ahci_host_priv *hpriv,
107 				struct device *dev)
108 {
109 	struct st_ahci_drv_data *drv_data = hpriv->plat_data;
110 
111 	drv_data->pwr = devm_reset_control_get(dev, "pwr-dwn");
112 	if (IS_ERR(drv_data->pwr)) {
113 		dev_info(dev, "power reset control not defined\n");
114 		drv_data->pwr = NULL;
115 	}
116 
117 	drv_data->sw_rst = devm_reset_control_get(dev, "sw-rst");
118 	if (IS_ERR(drv_data->sw_rst)) {
119 		dev_info(dev, "soft reset control not defined\n");
120 		drv_data->sw_rst = NULL;
121 	}
122 
123 	drv_data->pwr_rst = devm_reset_control_get(dev, "pwr-rst");
124 	if (IS_ERR(drv_data->pwr_rst)) {
125 		dev_dbg(dev, "power soft reset control not defined\n");
126 		drv_data->pwr_rst = NULL;
127 	}
128 
129 	return st_ahci_deassert_resets(hpriv, dev);
130 }
131 
132 static struct ata_port_operations st_ahci_port_ops = {
133 	.inherits	= &ahci_platform_ops,
134 	.host_stop	= st_ahci_host_stop,
135 };
136 
137 static const struct ata_port_info st_ahci_port_info = {
138 	.flags          = AHCI_FLAG_COMMON,
139 	.pio_mask       = ATA_PIO4,
140 	.udma_mask      = ATA_UDMA6,
141 	.port_ops       = &st_ahci_port_ops,
142 };
143 
144 static struct scsi_host_template ahci_platform_sht = {
145 	AHCI_SHT(DRV_NAME),
146 };
147 
148 static int st_ahci_probe(struct platform_device *pdev)
149 {
150 	struct device *dev = &pdev->dev;
151 	struct st_ahci_drv_data *drv_data;
152 	struct ahci_host_priv *hpriv;
153 	int err;
154 
155 	drv_data = devm_kzalloc(&pdev->dev, sizeof(*drv_data), GFP_KERNEL);
156 	if (!drv_data)
157 		return -ENOMEM;
158 
159 	hpriv = ahci_platform_get_resources(pdev);
160 	if (IS_ERR(hpriv))
161 		return PTR_ERR(hpriv);
162 	hpriv->plat_data = drv_data;
163 
164 	err = st_ahci_probe_resets(hpriv, &pdev->dev);
165 	if (err)
166 		return err;
167 
168 	err = ahci_platform_enable_resources(hpriv);
169 	if (err)
170 		return err;
171 
172 	st_ahci_configure_oob(hpriv->mmio);
173 
174 	of_property_read_u32(dev->of_node,
175 			     "ports-implemented", &hpriv->force_port_map);
176 
177 	err = ahci_platform_init_host(pdev, hpriv, &st_ahci_port_info,
178 				      &ahci_platform_sht);
179 	if (err) {
180 		ahci_platform_disable_resources(hpriv);
181 		return err;
182 	}
183 
184 	return 0;
185 }
186 
187 #ifdef CONFIG_PM_SLEEP
188 static int st_ahci_suspend(struct device *dev)
189 {
190 	struct ata_host *host = dev_get_drvdata(dev);
191 	struct ahci_host_priv *hpriv = host->private_data;
192 	struct st_ahci_drv_data *drv_data = hpriv->plat_data;
193 	int err;
194 
195 	err = ahci_platform_suspend_host(dev);
196 	if (err)
197 		return err;
198 
199 	if (drv_data->pwr) {
200 		err = reset_control_assert(drv_data->pwr);
201 		if (err) {
202 			dev_err(dev, "unable to pwrdwn");
203 			return err;
204 		}
205 	}
206 
207 	ahci_platform_disable_resources(hpriv);
208 
209 	return 0;
210 }
211 
212 static int st_ahci_resume(struct device *dev)
213 {
214 	struct ata_host *host = dev_get_drvdata(dev);
215 	struct ahci_host_priv *hpriv = host->private_data;
216 	int err;
217 
218 	err = ahci_platform_enable_resources(hpriv);
219 	if (err)
220 		return err;
221 
222 	err = st_ahci_deassert_resets(hpriv, dev);
223 	if (err) {
224 		ahci_platform_disable_resources(hpriv);
225 		return err;
226 	}
227 
228 	st_ahci_configure_oob(hpriv->mmio);
229 
230 	return ahci_platform_resume_host(dev);
231 }
232 #endif
233 
234 static SIMPLE_DEV_PM_OPS(st_ahci_pm_ops, st_ahci_suspend, st_ahci_resume);
235 
236 static const struct of_device_id st_ahci_match[] = {
237 	{ .compatible = "st,ahci", },
238 	{},
239 };
240 MODULE_DEVICE_TABLE(of, st_ahci_match);
241 
242 static struct platform_driver st_ahci_driver = {
243 	.driver = {
244 		.name = DRV_NAME,
245 		.pm = &st_ahci_pm_ops,
246 		.of_match_table = of_match_ptr(st_ahci_match),
247 	},
248 	.probe = st_ahci_probe,
249 	.remove = ata_platform_remove_one,
250 };
251 module_platform_driver(st_ahci_driver);
252 
253 MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue@st.com>");
254 MODULE_AUTHOR("Francesco Virlinzi <francesco.virlinzi@st.com>");
255 MODULE_DESCRIPTION("STMicroelectronics SATA AHCI Driver");
256 MODULE_LICENSE("GPL v2");
257