xref: /openbmc/linux/drivers/ata/ahci_mvebu.c (revision 1edd0337)
1 /*
2  * AHCI glue platform driver for Marvell EBU SOCs
3  *
4  * Copyright (C) 2014 Marvell
5  *
6  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
7  * Marcin Wojtas <mw@semihalf.com>
8  *
9  * This file is licensed under the terms of the GNU General Public
10  * License version 2.  This program is licensed "as is" without any
11  * warranty of any kind, whether express or implied.
12  */
13 
14 #include <linux/ahci_platform.h>
15 #include <linux/kernel.h>
16 #include <linux/mbus.h>
17 #include <linux/module.h>
18 #include <linux/of_device.h>
19 #include <linux/platform_device.h>
20 #include "ahci.h"
21 
22 #define DRV_NAME "ahci-mvebu"
23 
24 #define AHCI_VENDOR_SPECIFIC_0_ADDR  0xa0
25 #define AHCI_VENDOR_SPECIFIC_0_DATA  0xa4
26 
27 #define AHCI_WINDOW_CTRL(win)	(0x60 + ((win) << 4))
28 #define AHCI_WINDOW_BASE(win)	(0x64 + ((win) << 4))
29 #define AHCI_WINDOW_SIZE(win)	(0x68 + ((win) << 4))
30 
31 struct ahci_mvebu_plat_data {
32 	int (*plat_config)(struct ahci_host_priv *hpriv);
33 	unsigned int flags;
34 };
35 
36 static void ahci_mvebu_mbus_config(struct ahci_host_priv *hpriv,
37 				   const struct mbus_dram_target_info *dram)
38 {
39 	int i;
40 
41 	for (i = 0; i < 4; i++) {
42 		writel(0, hpriv->mmio + AHCI_WINDOW_CTRL(i));
43 		writel(0, hpriv->mmio + AHCI_WINDOW_BASE(i));
44 		writel(0, hpriv->mmio + AHCI_WINDOW_SIZE(i));
45 	}
46 
47 	for (i = 0; i < dram->num_cs; i++) {
48 		const struct mbus_dram_window *cs = dram->cs + i;
49 
50 		writel((cs->mbus_attr << 8) |
51 		       (dram->mbus_dram_target_id << 4) | 1,
52 		       hpriv->mmio + AHCI_WINDOW_CTRL(i));
53 		writel(cs->base >> 16, hpriv->mmio + AHCI_WINDOW_BASE(i));
54 		writel(((cs->size - 1) & 0xffff0000),
55 		       hpriv->mmio + AHCI_WINDOW_SIZE(i));
56 	}
57 }
58 
59 static void ahci_mvebu_regret_option(struct ahci_host_priv *hpriv)
60 {
61 	/*
62 	 * Enable the regret bit to allow the SATA unit to regret a
63 	 * request that didn't receive an acknowlegde and avoid a
64 	 * deadlock
65 	 */
66 	writel(0x4, hpriv->mmio + AHCI_VENDOR_SPECIFIC_0_ADDR);
67 	writel(0x80, hpriv->mmio + AHCI_VENDOR_SPECIFIC_0_DATA);
68 }
69 
70 static int ahci_mvebu_armada_380_config(struct ahci_host_priv *hpriv)
71 {
72 	const struct mbus_dram_target_info *dram;
73 	int rc = 0;
74 
75 	dram = mv_mbus_dram_info();
76 	if (dram)
77 		ahci_mvebu_mbus_config(hpriv, dram);
78 	else
79 		rc = -ENODEV;
80 
81 	ahci_mvebu_regret_option(hpriv);
82 
83 	return rc;
84 }
85 
86 static int ahci_mvebu_armada_3700_config(struct ahci_host_priv *hpriv)
87 {
88 	u32 reg;
89 
90 	writel(0, hpriv->mmio + AHCI_VENDOR_SPECIFIC_0_ADDR);
91 
92 	reg = readl(hpriv->mmio + AHCI_VENDOR_SPECIFIC_0_DATA);
93 	reg |= BIT(6);
94 	writel(reg, hpriv->mmio + AHCI_VENDOR_SPECIFIC_0_DATA);
95 
96 	return 0;
97 }
98 
99 /**
100  * ahci_mvebu_stop_engine
101  *
102  * @ap:	Target ata port
103  *
104  * Errata Ref#226 - SATA Disk HOT swap issue when connected through
105  * Port Multiplier in FIS-based Switching mode.
106  *
107  * To avoid the issue, according to design, the bits[11:8, 0] of
108  * register PxFBS are cleared when Port Command and Status (0x18) bit[0]
109  * changes its value from 1 to 0, i.e. falling edge of Port
110  * Command and Status bit[0] sends PULSE that resets PxFBS
111  * bits[11:8; 0].
112  *
113  * This function is used to override function of "ahci_stop_engine"
114  * from libahci.c by adding the mvebu work around(WA) to save PxFBS
115  * value before the PxCMD ST write of 0, then restore PxFBS value.
116  *
117  * Return: 0 on success; Error code otherwise.
118  */
119 static int ahci_mvebu_stop_engine(struct ata_port *ap)
120 {
121 	void __iomem *port_mmio = ahci_port_base(ap);
122 	u32 tmp, port_fbs;
123 
124 	tmp = readl(port_mmio + PORT_CMD);
125 
126 	/* check if the HBA is idle */
127 	if ((tmp & (PORT_CMD_START | PORT_CMD_LIST_ON)) == 0)
128 		return 0;
129 
130 	/* save the port PxFBS register for later restore */
131 	port_fbs = readl(port_mmio + PORT_FBS);
132 
133 	/* setting HBA to idle */
134 	tmp &= ~PORT_CMD_START;
135 	writel(tmp, port_mmio + PORT_CMD);
136 
137 	/*
138 	 * bit #15 PxCMD signal doesn't clear PxFBS,
139 	 * restore the PxFBS register right after clearing the PxCMD ST,
140 	 * no need to wait for the PxCMD bit #15.
141 	 */
142 	writel(port_fbs, port_mmio + PORT_FBS);
143 
144 	/* wait for engine to stop. This could be as long as 500 msec */
145 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
146 				PORT_CMD_LIST_ON, PORT_CMD_LIST_ON, 1, 500);
147 	if (tmp & PORT_CMD_LIST_ON)
148 		return -EIO;
149 
150 	return 0;
151 }
152 
153 #ifdef CONFIG_PM_SLEEP
154 static int ahci_mvebu_suspend(struct platform_device *pdev, pm_message_t state)
155 {
156 	return ahci_platform_suspend_host(&pdev->dev);
157 }
158 
159 static int ahci_mvebu_resume(struct platform_device *pdev)
160 {
161 	struct ata_host *host = platform_get_drvdata(pdev);
162 	struct ahci_host_priv *hpriv = host->private_data;
163 	const struct ahci_mvebu_plat_data *pdata = hpriv->plat_data;
164 
165 	pdata->plat_config(hpriv);
166 
167 	return ahci_platform_resume_host(&pdev->dev);
168 }
169 #else
170 #define ahci_mvebu_suspend NULL
171 #define ahci_mvebu_resume NULL
172 #endif
173 
174 static const struct ata_port_info ahci_mvebu_port_info = {
175 	.flags	   = AHCI_FLAG_COMMON,
176 	.pio_mask  = ATA_PIO4,
177 	.udma_mask = ATA_UDMA6,
178 	.port_ops  = &ahci_platform_ops,
179 };
180 
181 static struct scsi_host_template ahci_platform_sht = {
182 	AHCI_SHT(DRV_NAME),
183 };
184 
185 static int ahci_mvebu_probe(struct platform_device *pdev)
186 {
187 	const struct ahci_mvebu_plat_data *pdata;
188 	struct ahci_host_priv *hpriv;
189 	int rc;
190 
191 	pdata = of_device_get_match_data(&pdev->dev);
192 	if (!pdata)
193 		return -EINVAL;
194 
195 	hpriv = ahci_platform_get_resources(pdev, 0);
196 	if (IS_ERR(hpriv))
197 		return PTR_ERR(hpriv);
198 
199 	hpriv->flags |= pdata->flags;
200 	hpriv->plat_data = (void *)pdata;
201 
202 	rc = ahci_platform_enable_resources(hpriv);
203 	if (rc)
204 		return rc;
205 
206 	hpriv->stop_engine = ahci_mvebu_stop_engine;
207 
208 	rc = pdata->plat_config(hpriv);
209 	if (rc)
210 		goto disable_resources;
211 
212 	rc = ahci_platform_init_host(pdev, hpriv, &ahci_mvebu_port_info,
213 				     &ahci_platform_sht);
214 	if (rc)
215 		goto disable_resources;
216 
217 	return 0;
218 
219 disable_resources:
220 	ahci_platform_disable_resources(hpriv);
221 	return rc;
222 }
223 
224 static const struct ahci_mvebu_plat_data ahci_mvebu_armada_380_plat_data = {
225 	.plat_config = ahci_mvebu_armada_380_config,
226 };
227 
228 static const struct ahci_mvebu_plat_data ahci_mvebu_armada_3700_plat_data = {
229 	.plat_config = ahci_mvebu_armada_3700_config,
230 	.flags = AHCI_HFLAG_SUSPEND_PHYS,
231 };
232 
233 static const struct of_device_id ahci_mvebu_of_match[] = {
234 	{
235 		.compatible = "marvell,armada-380-ahci",
236 		.data = &ahci_mvebu_armada_380_plat_data,
237 	},
238 	{
239 		.compatible = "marvell,armada-3700-ahci",
240 		.data = &ahci_mvebu_armada_3700_plat_data,
241 	},
242 	{ /* sentinel */ }
243 };
244 MODULE_DEVICE_TABLE(of, ahci_mvebu_of_match);
245 
246 static struct platform_driver ahci_mvebu_driver = {
247 	.probe = ahci_mvebu_probe,
248 	.remove = ata_platform_remove_one,
249 	.suspend = ahci_mvebu_suspend,
250 	.resume = ahci_mvebu_resume,
251 	.driver = {
252 		.name = DRV_NAME,
253 		.of_match_table = ahci_mvebu_of_match,
254 	},
255 };
256 module_platform_driver(ahci_mvebu_driver);
257 
258 MODULE_DESCRIPTION("Marvell EBU AHCI SATA driver");
259 MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@free-electrons.com>, Marcin Wojtas <mw@semihalf.com>");
260 MODULE_LICENSE("GPL");
261 MODULE_ALIAS("platform:ahci_mvebu");
262