xref: /openbmc/linux/drivers/ata/ahci_st.c (revision 234489ac)
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 const 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 st_ahci_drv_data *drv_data;
148 	struct ahci_host_priv *hpriv;
149 	int err;
150 
151 	drv_data = devm_kzalloc(&pdev->dev, sizeof(*drv_data), GFP_KERNEL);
152 	if (!drv_data)
153 		return -ENOMEM;
154 
155 	hpriv = ahci_platform_get_resources(pdev, 0);
156 	if (IS_ERR(hpriv))
157 		return PTR_ERR(hpriv);
158 	hpriv->plat_data = drv_data;
159 
160 	err = st_ahci_probe_resets(hpriv, &pdev->dev);
161 	if (err)
162 		return err;
163 
164 	err = ahci_platform_enable_resources(hpriv);
165 	if (err)
166 		return err;
167 
168 	st_ahci_configure_oob(hpriv->mmio);
169 
170 	err = ahci_platform_init_host(pdev, hpriv, &st_ahci_port_info,
171 				      &ahci_platform_sht);
172 	if (err) {
173 		ahci_platform_disable_resources(hpriv);
174 		return err;
175 	}
176 
177 	return 0;
178 }
179 
180 #ifdef CONFIG_PM_SLEEP
181 static int st_ahci_suspend(struct device *dev)
182 {
183 	struct ata_host *host = dev_get_drvdata(dev);
184 	struct ahci_host_priv *hpriv = host->private_data;
185 	struct st_ahci_drv_data *drv_data = hpriv->plat_data;
186 	int err;
187 
188 	err = ahci_platform_suspend_host(dev);
189 	if (err)
190 		return err;
191 
192 	if (drv_data->pwr) {
193 		err = reset_control_assert(drv_data->pwr);
194 		if (err) {
195 			dev_err(dev, "unable to pwrdwn");
196 			return err;
197 		}
198 	}
199 
200 	ahci_platform_disable_resources(hpriv);
201 
202 	return 0;
203 }
204 
205 static int st_ahci_resume(struct device *dev)
206 {
207 	struct ata_host *host = dev_get_drvdata(dev);
208 	struct ahci_host_priv *hpriv = host->private_data;
209 	int err;
210 
211 	err = ahci_platform_enable_resources(hpriv);
212 	if (err)
213 		return err;
214 
215 	err = st_ahci_deassert_resets(hpriv, dev);
216 	if (err) {
217 		ahci_platform_disable_resources(hpriv);
218 		return err;
219 	}
220 
221 	st_ahci_configure_oob(hpriv->mmio);
222 
223 	return ahci_platform_resume_host(dev);
224 }
225 #endif
226 
227 static SIMPLE_DEV_PM_OPS(st_ahci_pm_ops, st_ahci_suspend, st_ahci_resume);
228 
229 static const struct of_device_id st_ahci_match[] = {
230 	{ .compatible = "st,ahci", },
231 	{ /* sentinel */ }
232 };
233 MODULE_DEVICE_TABLE(of, st_ahci_match);
234 
235 static struct platform_driver st_ahci_driver = {
236 	.driver = {
237 		.name = DRV_NAME,
238 		.pm = &st_ahci_pm_ops,
239 		.of_match_table = st_ahci_match,
240 	},
241 	.probe = st_ahci_probe,
242 	.remove = ata_platform_remove_one,
243 };
244 module_platform_driver(st_ahci_driver);
245 
246 MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue@st.com>");
247 MODULE_AUTHOR("Francesco Virlinzi <francesco.virlinzi@st.com>");
248 MODULE_DESCRIPTION("STMicroelectronics SATA AHCI Driver");
249 MODULE_LICENSE("GPL v2");
250