xref: /openbmc/linux/drivers/ata/pata_imx.c (revision d9fd5a71)
1 /*
2  * Freescale iMX PATA driver
3  *
4  * Copyright (C) 2011 Arnaud Patard <arnaud.patard@rtp-net.org>
5  *
6  * Based on pata_platform - Copyright (C) 2006 - 2007  Paul Mundt
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License.  See the file "COPYING" in the main directory of this archive
10  * for more details.
11  *
12  * TODO:
13  * - dmaengine support
14  */
15 
16 #include <linux/ata.h>
17 #include <linux/clk.h>
18 #include <linux/libata.h>
19 #include <linux/module.h>
20 #include <linux/mod_devicetable.h>
21 #include <linux/platform_device.h>
22 
23 #define DRV_NAME "pata_imx"
24 
25 #define PATA_IMX_ATA_TIME_OFF		0x00
26 #define PATA_IMX_ATA_TIME_ON		0x01
27 #define PATA_IMX_ATA_TIME_1		0x02
28 #define PATA_IMX_ATA_TIME_2W		0x03
29 #define PATA_IMX_ATA_TIME_2R		0x04
30 #define PATA_IMX_ATA_TIME_AX		0x05
31 #define PATA_IMX_ATA_TIME_PIO_RDX	0x06
32 #define PATA_IMX_ATA_TIME_4		0x07
33 #define PATA_IMX_ATA_TIME_9		0x08
34 
35 #define PATA_IMX_ATA_CONTROL		0x24
36 #define PATA_IMX_ATA_CTRL_FIFO_RST_B	(1<<7)
37 #define PATA_IMX_ATA_CTRL_ATA_RST_B	(1<<6)
38 #define PATA_IMX_ATA_CTRL_IORDY_EN	(1<<0)
39 #define PATA_IMX_ATA_INT_EN		0x2C
40 #define PATA_IMX_ATA_INTR_ATA_INTRQ2	(1<<3)
41 #define PATA_IMX_DRIVE_DATA		0xA0
42 #define PATA_IMX_DRIVE_CONTROL		0xD8
43 
44 static u32 pio_t4[] = { 30,  20,  15,  10,  10 };
45 static u32 pio_t9[] = { 20,  15,  10,  10,  10 };
46 static u32 pio_tA[] = { 35,  35,  35,  35,  35 };
47 
48 struct pata_imx_priv {
49 	struct clk *clk;
50 	/* timings/interrupt/control regs */
51 	void __iomem *host_regs;
52 	u32 ata_ctl;
53 };
54 
55 static void pata_imx_set_timing(struct ata_device *adev,
56 				struct pata_imx_priv *priv)
57 {
58 	struct ata_timing timing;
59 	unsigned long clkrate;
60 	u32 T, mode;
61 
62 	clkrate = clk_get_rate(priv->clk);
63 
64 	if (adev->pio_mode < XFER_PIO_0 || adev->pio_mode > XFER_PIO_4 ||
65 	    !clkrate)
66 		return;
67 
68 	T = 1000000000 / clkrate;
69 	ata_timing_compute(adev, adev->pio_mode, &timing, T * 1000, 0);
70 
71 	mode = adev->pio_mode - XFER_PIO_0;
72 
73 	writeb(3, priv->host_regs + PATA_IMX_ATA_TIME_OFF);
74 	writeb(3, priv->host_regs + PATA_IMX_ATA_TIME_ON);
75 	writeb(timing.setup, priv->host_regs + PATA_IMX_ATA_TIME_1);
76 	writeb(timing.act8b, priv->host_regs + PATA_IMX_ATA_TIME_2W);
77 	writeb(timing.act8b, priv->host_regs + PATA_IMX_ATA_TIME_2R);
78 	writeb(1, priv->host_regs + PATA_IMX_ATA_TIME_PIO_RDX);
79 
80 	writeb(pio_t4[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_4);
81 	writeb(pio_t9[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_9);
82 	writeb(pio_tA[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_AX);
83 }
84 
85 static void pata_imx_set_piomode(struct ata_port *ap, struct ata_device *adev)
86 {
87 	struct pata_imx_priv *priv = ap->host->private_data;
88 	u32 val;
89 
90 	pata_imx_set_timing(adev, priv);
91 
92 	val = __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
93 	if (ata_pio_need_iordy(adev))
94 		val |= PATA_IMX_ATA_CTRL_IORDY_EN;
95 	else
96 		val &= ~PATA_IMX_ATA_CTRL_IORDY_EN;
97 	__raw_writel(val, priv->host_regs + PATA_IMX_ATA_CONTROL);
98 }
99 
100 static struct scsi_host_template pata_imx_sht = {
101 	ATA_PIO_SHT(DRV_NAME),
102 };
103 
104 static struct ata_port_operations pata_imx_port_ops = {
105 	.inherits		= &ata_sff_port_ops,
106 	.sff_data_xfer		= ata_sff_data_xfer32,
107 	.cable_detect		= ata_cable_unknown,
108 	.set_piomode		= pata_imx_set_piomode,
109 };
110 
111 static void pata_imx_setup_port(struct ata_ioports *ioaddr)
112 {
113 	/* Fixup the port shift for platforms that need it */
114 	ioaddr->data_addr	= ioaddr->cmd_addr + (ATA_REG_DATA    << 2);
115 	ioaddr->error_addr	= ioaddr->cmd_addr + (ATA_REG_ERR     << 2);
116 	ioaddr->feature_addr	= ioaddr->cmd_addr + (ATA_REG_FEATURE << 2);
117 	ioaddr->nsect_addr	= ioaddr->cmd_addr + (ATA_REG_NSECT   << 2);
118 	ioaddr->lbal_addr	= ioaddr->cmd_addr + (ATA_REG_LBAL    << 2);
119 	ioaddr->lbam_addr	= ioaddr->cmd_addr + (ATA_REG_LBAM    << 2);
120 	ioaddr->lbah_addr	= ioaddr->cmd_addr + (ATA_REG_LBAH    << 2);
121 	ioaddr->device_addr	= ioaddr->cmd_addr + (ATA_REG_DEVICE  << 2);
122 	ioaddr->status_addr	= ioaddr->cmd_addr + (ATA_REG_STATUS  << 2);
123 	ioaddr->command_addr	= ioaddr->cmd_addr + (ATA_REG_CMD     << 2);
124 }
125 
126 static int pata_imx_probe(struct platform_device *pdev)
127 {
128 	struct ata_host *host;
129 	struct ata_port *ap;
130 	struct pata_imx_priv *priv;
131 	int irq = 0;
132 	struct resource *io_res;
133 	int ret;
134 
135 	irq = platform_get_irq(pdev, 0);
136 	if (irq < 0)
137 		return irq;
138 
139 	priv = devm_kzalloc(&pdev->dev,
140 				sizeof(struct pata_imx_priv), GFP_KERNEL);
141 	if (!priv)
142 		return -ENOMEM;
143 
144 	priv->clk = devm_clk_get(&pdev->dev, NULL);
145 	if (IS_ERR(priv->clk)) {
146 		dev_err(&pdev->dev, "Failed to get clock\n");
147 		return PTR_ERR(priv->clk);
148 	}
149 
150 	ret = clk_prepare_enable(priv->clk);
151 	if (ret)
152 		return ret;
153 
154 	host = ata_host_alloc(&pdev->dev, 1);
155 	if (!host) {
156 		ret = -ENOMEM;
157 		goto err;
158 	}
159 
160 	host->private_data = priv;
161 	ap = host->ports[0];
162 
163 	ap->ops = &pata_imx_port_ops;
164 	ap->pio_mask = ATA_PIO4;
165 	ap->flags |= ATA_FLAG_SLAVE_POSS;
166 
167 	io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
168 	priv->host_regs = devm_ioremap_resource(&pdev->dev, io_res);
169 	if (IS_ERR(priv->host_regs)) {
170 		ret = PTR_ERR(priv->host_regs);
171 		goto err;
172 	}
173 
174 	ap->ioaddr.cmd_addr = priv->host_regs + PATA_IMX_DRIVE_DATA;
175 	ap->ioaddr.ctl_addr = priv->host_regs + PATA_IMX_DRIVE_CONTROL;
176 
177 	ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;
178 
179 	pata_imx_setup_port(&ap->ioaddr);
180 
181 	ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
182 		(unsigned long long)io_res->start + PATA_IMX_DRIVE_DATA,
183 		(unsigned long long)io_res->start + PATA_IMX_DRIVE_CONTROL);
184 
185 	/* deassert resets */
186 	__raw_writel(PATA_IMX_ATA_CTRL_FIFO_RST_B |
187 			PATA_IMX_ATA_CTRL_ATA_RST_B,
188 			priv->host_regs + PATA_IMX_ATA_CONTROL);
189 	/* enable interrupts */
190 	__raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
191 			priv->host_regs + PATA_IMX_ATA_INT_EN);
192 
193 	/* activate */
194 	ret = ata_host_activate(host, irq, ata_sff_interrupt, 0,
195 				&pata_imx_sht);
196 
197 	if (ret)
198 		goto err;
199 
200 	return 0;
201 err:
202 	clk_disable_unprepare(priv->clk);
203 
204 	return ret;
205 }
206 
207 static int pata_imx_remove(struct platform_device *pdev)
208 {
209 	struct ata_host *host = platform_get_drvdata(pdev);
210 	struct pata_imx_priv *priv = host->private_data;
211 
212 	ata_host_detach(host);
213 
214 	__raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
215 
216 	clk_disable_unprepare(priv->clk);
217 
218 	return 0;
219 }
220 
221 #ifdef CONFIG_PM_SLEEP
222 static int pata_imx_suspend(struct device *dev)
223 {
224 	struct ata_host *host = dev_get_drvdata(dev);
225 	struct pata_imx_priv *priv = host->private_data;
226 	int ret;
227 
228 	ret = ata_host_suspend(host, PMSG_SUSPEND);
229 	if (!ret) {
230 		__raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
231 		priv->ata_ctl =
232 			__raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
233 		clk_disable_unprepare(priv->clk);
234 	}
235 
236 	return ret;
237 }
238 
239 static int pata_imx_resume(struct device *dev)
240 {
241 	struct ata_host *host = dev_get_drvdata(dev);
242 	struct pata_imx_priv *priv = host->private_data;
243 
244 	int ret = clk_prepare_enable(priv->clk);
245 	if (ret)
246 		return ret;
247 
248 	__raw_writel(priv->ata_ctl, priv->host_regs + PATA_IMX_ATA_CONTROL);
249 
250 	__raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
251 			priv->host_regs + PATA_IMX_ATA_INT_EN);
252 
253 	ata_host_resume(host);
254 
255 	return 0;
256 }
257 #endif
258 
259 static SIMPLE_DEV_PM_OPS(pata_imx_pm_ops, pata_imx_suspend, pata_imx_resume);
260 
261 static const struct of_device_id imx_pata_dt_ids[] = {
262 	{
263 		.compatible = "fsl,imx27-pata",
264 	}, {
265 		/* sentinel */
266 	}
267 };
268 MODULE_DEVICE_TABLE(of, imx_pata_dt_ids);
269 
270 static struct platform_driver pata_imx_driver = {
271 	.probe		= pata_imx_probe,
272 	.remove		= pata_imx_remove,
273 	.driver = {
274 		.name		= DRV_NAME,
275 		.of_match_table	= imx_pata_dt_ids,
276 		.pm		= &pata_imx_pm_ops,
277 	},
278 };
279 
280 module_platform_driver(pata_imx_driver);
281 
282 MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>");
283 MODULE_DESCRIPTION("low-level driver for iMX PATA");
284 MODULE_LICENSE("GPL");
285 MODULE_ALIAS("platform:" DRV_NAME);
286