xref: /openbmc/linux/drivers/ata/ahci_st.c (revision 0a94608f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 STMicroelectronics Limited
4  *
5  * Authors: Francesco Virlinzi <francesco.virlinzi@st.com>
6  *	    Alexandre Torgue <alexandre.torgue@st.com>
7  */
8 
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/export.h>
12 #include <linux/platform_device.h>
13 #include <linux/clk.h>
14 #include <linux/of.h>
15 #include <linux/ahci_platform.h>
16 #include <linux/libata.h>
17 #include <linux/reset.h>
18 #include <linux/io.h>
19 #include <linux/dma-mapping.h>
20 
21 #include "ahci.h"
22 
23 #define DRV_NAME  "st_ahci"
24 
25 #define ST_AHCI_OOBR			0xbc
26 #define ST_AHCI_OOBR_WE			BIT(31)
27 #define ST_AHCI_OOBR_CWMIN_SHIFT	24
28 #define ST_AHCI_OOBR_CWMAX_SHIFT	16
29 #define ST_AHCI_OOBR_CIMIN_SHIFT	8
30 #define ST_AHCI_OOBR_CIMAX_SHIFT	0
31 
32 struct st_ahci_drv_data {
33 	struct platform_device *ahci;
34 	struct reset_control *pwr;
35 	struct reset_control *sw_rst;
36 	struct reset_control *pwr_rst;
37 };
38 
39 static void st_ahci_configure_oob(void __iomem *mmio)
40 {
41 	unsigned long old_val, new_val;
42 
43 	new_val = (0x02 << ST_AHCI_OOBR_CWMIN_SHIFT) |
44 		  (0x04 << ST_AHCI_OOBR_CWMAX_SHIFT) |
45 		  (0x08 << ST_AHCI_OOBR_CIMIN_SHIFT) |
46 		  (0x0C << ST_AHCI_OOBR_CIMAX_SHIFT);
47 
48 	old_val = readl(mmio + ST_AHCI_OOBR);
49 	writel(old_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
50 	writel(new_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
51 	writel(new_val, mmio + ST_AHCI_OOBR);
52 }
53 
54 static int st_ahci_deassert_resets(struct ahci_host_priv *hpriv,
55 				struct device *dev)
56 {
57 	struct st_ahci_drv_data *drv_data = hpriv->plat_data;
58 	int err;
59 
60 	if (drv_data->pwr) {
61 		err = reset_control_deassert(drv_data->pwr);
62 		if (err) {
63 			dev_err(dev, "unable to bring out of pwrdwn\n");
64 			return err;
65 		}
66 	}
67 
68 	if (drv_data->sw_rst) {
69 		err = reset_control_deassert(drv_data->sw_rst);
70 		if (err) {
71 			dev_err(dev, "unable to bring out of sw-rst\n");
72 			return err;
73 		}
74 	}
75 
76 	if (drv_data->pwr_rst) {
77 		err = reset_control_deassert(drv_data->pwr_rst);
78 		if (err) {
79 			dev_err(dev, "unable to bring out of pwr-rst\n");
80 			return err;
81 		}
82 	}
83 
84 	return 0;
85 }
86 
87 static void st_ahci_host_stop(struct ata_host *host)
88 {
89 	struct ahci_host_priv *hpriv = host->private_data;
90 	struct st_ahci_drv_data *drv_data = hpriv->plat_data;
91 	struct device *dev = host->dev;
92 	int err;
93 
94 	if (drv_data->pwr) {
95 		err = reset_control_assert(drv_data->pwr);
96 		if (err)
97 			dev_err(dev, "unable to pwrdwn\n");
98 	}
99 
100 	ahci_platform_disable_resources(hpriv);
101 }
102 
103 static int st_ahci_probe_resets(struct ahci_host_priv *hpriv,
104 				struct device *dev)
105 {
106 	struct st_ahci_drv_data *drv_data = hpriv->plat_data;
107 
108 	drv_data->pwr = devm_reset_control_get(dev, "pwr-dwn");
109 	if (IS_ERR(drv_data->pwr)) {
110 		dev_info(dev, "power reset control not defined\n");
111 		drv_data->pwr = NULL;
112 	}
113 
114 	drv_data->sw_rst = devm_reset_control_get(dev, "sw-rst");
115 	if (IS_ERR(drv_data->sw_rst)) {
116 		dev_info(dev, "soft reset control not defined\n");
117 		drv_data->sw_rst = NULL;
118 	}
119 
120 	drv_data->pwr_rst = devm_reset_control_get(dev, "pwr-rst");
121 	if (IS_ERR(drv_data->pwr_rst)) {
122 		dev_dbg(dev, "power soft reset control not defined\n");
123 		drv_data->pwr_rst = NULL;
124 	}
125 
126 	return st_ahci_deassert_resets(hpriv, dev);
127 }
128 
129 static struct ata_port_operations st_ahci_port_ops = {
130 	.inherits	= &ahci_platform_ops,
131 	.host_stop	= st_ahci_host_stop,
132 };
133 
134 static const struct ata_port_info st_ahci_port_info = {
135 	.flags          = AHCI_FLAG_COMMON,
136 	.pio_mask       = ATA_PIO4,
137 	.udma_mask      = ATA_UDMA6,
138 	.port_ops       = &st_ahci_port_ops,
139 };
140 
141 static struct scsi_host_template ahci_platform_sht = {
142 	AHCI_SHT(DRV_NAME),
143 };
144 
145 static int st_ahci_probe(struct platform_device *pdev)
146 {
147 	struct device *dev = &pdev->dev;
148 	struct st_ahci_drv_data *drv_data;
149 	struct ahci_host_priv *hpriv;
150 	int err;
151 
152 	drv_data = devm_kzalloc(&pdev->dev, sizeof(*drv_data), GFP_KERNEL);
153 	if (!drv_data)
154 		return -ENOMEM;
155 
156 	hpriv = ahci_platform_get_resources(pdev, 0);
157 	if (IS_ERR(hpriv))
158 		return PTR_ERR(hpriv);
159 	hpriv->plat_data = drv_data;
160 
161 	err = st_ahci_probe_resets(hpriv, &pdev->dev);
162 	if (err)
163 		return err;
164 
165 	err = ahci_platform_enable_resources(hpriv);
166 	if (err)
167 		return err;
168 
169 	st_ahci_configure_oob(hpriv->mmio);
170 
171 	of_property_read_u32(dev->of_node,
172 			     "ports-implemented", &hpriv->force_port_map);
173 
174 	err = ahci_platform_init_host(pdev, hpriv, &st_ahci_port_info,
175 				      &ahci_platform_sht);
176 	if (err) {
177 		ahci_platform_disable_resources(hpriv);
178 		return err;
179 	}
180 
181 	return 0;
182 }
183 
184 #ifdef CONFIG_PM_SLEEP
185 static int st_ahci_suspend(struct device *dev)
186 {
187 	struct ata_host *host = dev_get_drvdata(dev);
188 	struct ahci_host_priv *hpriv = host->private_data;
189 	struct st_ahci_drv_data *drv_data = hpriv->plat_data;
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 ata_host *host = dev_get_drvdata(dev);
212 	struct ahci_host_priv *hpriv = host->private_data;
213 	int err;
214 
215 	err = ahci_platform_enable_resources(hpriv);
216 	if (err)
217 		return err;
218 
219 	err = st_ahci_deassert_resets(hpriv, dev);
220 	if (err) {
221 		ahci_platform_disable_resources(hpriv);
222 		return err;
223 	}
224 
225 	st_ahci_configure_oob(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 	{ /* sentinel */ }
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