xref: /openbmc/linux/drivers/ata/pata_ixp4xx_cf.c (revision f71a261a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ixp4xx PATA/Compact Flash driver
4  * Copyright (C) 2006-07 Tower Technologies
5  * Author: Alessandro Zummo <a.zummo@towertech.it>
6  *
7  * An ATA driver to handle a Compact Flash connected
8  * to the ixp4xx expansion bus in TrueIDE mode. The CF
9  * must have it chip selects connected to two CS lines
10  * on the ixp4xx. In the irq is not available, you might
11  * want to modify both this driver and libata to run in
12  * polling mode.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/mfd/syscon.h>
17 #include <linux/module.h>
18 #include <linux/libata.h>
19 #include <linux/irq.h>
20 #include <linux/platform_device.h>
21 #include <linux/regmap.h>
22 #include <scsi/scsi_host.h>
23 
24 #define DRV_NAME	"pata_ixp4xx_cf"
25 #define DRV_VERSION	"1.0"
26 
27 struct ixp4xx_pata {
28 	struct ata_host *host;
29 	struct regmap *rmap;
30 	u32 cmd_csreg;
31 	void __iomem *cmd;
32 	void __iomem *ctl;
33 };
34 
35 #define IXP4XX_EXP_TIMING_STRIDE	0x04
36 /* The timings for the chipselect is in bits 29..16 */
37 #define IXP4XX_EXP_T1_T5_MASK	GENMASK(29, 16)
38 #define IXP4XX_EXP_PIO_0_8	0x0a470000
39 #define IXP4XX_EXP_PIO_1_8	0x06430000
40 #define IXP4XX_EXP_PIO_2_8	0x02410000
41 #define IXP4XX_EXP_PIO_3_8	0x00820000
42 #define IXP4XX_EXP_PIO_4_8	0x00400000
43 #define IXP4XX_EXP_PIO_0_16	0x29640000
44 #define IXP4XX_EXP_PIO_1_16	0x05030000
45 #define IXP4XX_EXP_PIO_2_16	0x00b20000
46 #define IXP4XX_EXP_PIO_3_16	0x00820000
47 #define IXP4XX_EXP_PIO_4_16	0x00400000
48 #define IXP4XX_EXP_BW_MASK	(BIT(6)|BIT(0))
49 #define IXP4XX_EXP_BYTE_RD16	BIT(6) /* Byte reads on half-word devices */
50 #define IXP4XX_EXP_BYTE_EN	BIT(0) /* Use 8bit data bus if set */
51 
52 static void ixp4xx_set_8bit_timing(struct ixp4xx_pata *ixpp, u8 pio_mode)
53 {
54 	switch (pio_mode) {
55 	case XFER_PIO_0:
56 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
57 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_0_8);
58 		break;
59 	case XFER_PIO_1:
60 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
61 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_1_8);
62 		break;
63 	case XFER_PIO_2:
64 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
65 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_2_8);
66 		break;
67 	case XFER_PIO_3:
68 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
69 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_3_8);
70 		break;
71 	case XFER_PIO_4:
72 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
73 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_4_8);
74 		break;
75 	default:
76 		break;
77 	}
78 	regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
79 			   IXP4XX_EXP_BW_MASK, IXP4XX_EXP_BYTE_RD16|IXP4XX_EXP_BYTE_EN);
80 }
81 
82 static void ixp4xx_set_16bit_timing(struct ixp4xx_pata *ixpp, u8 pio_mode)
83 {
84 	switch (pio_mode){
85 	case XFER_PIO_0:
86 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
87 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_0_16);
88 		break;
89 	case XFER_PIO_1:
90 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
91 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_1_16);
92 		break;
93 	case XFER_PIO_2:
94 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
95 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_2_16);
96 		break;
97 	case XFER_PIO_3:
98 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
99 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_3_16);
100 		break;
101 	case XFER_PIO_4:
102 		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
103 				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_4_16);
104 		break;
105 	default:
106 		break;
107 	}
108 	regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
109 			   IXP4XX_EXP_BW_MASK, IXP4XX_EXP_BYTE_RD16);
110 }
111 
112 /* This sets up the timing on the chipselect CMD accordingly */
113 static void ixp4xx_set_piomode(struct ata_port *ap, struct ata_device *adev)
114 {
115 	struct ixp4xx_pata *ixpp = ap->host->private_data;
116 
117 	ata_dev_info(adev, "configured for PIO%d 8bit\n",
118 		       adev->pio_mode - XFER_PIO_0);
119 	ixp4xx_set_8bit_timing(ixpp, adev->pio_mode);
120 }
121 
122 
123 static unsigned int ixp4xx_mmio_data_xfer(struct ata_queued_cmd *qc,
124 					  unsigned char *buf, unsigned int buflen, int rw)
125 {
126 	unsigned int i;
127 	unsigned int words = buflen >> 1;
128 	u16 *buf16 = (u16 *) buf;
129 	struct ata_device *adev = qc->dev;
130 	struct ata_port *ap = qc->dev->link->ap;
131 	void __iomem *mmio = ap->ioaddr.data_addr;
132 	struct ixp4xx_pata *ixpp = ap->host->private_data;
133 	unsigned long flags;
134 
135 	ata_dev_dbg(adev, "%s %d bytes\n", (rw == READ) ? "READ" : "WRITE",
136 		    buflen);
137 	spin_lock_irqsave(ap->lock, flags);
138 
139 	/* set the expansion bus in 16bit mode and restore
140 	 * 8 bit mode after the transaction.
141 	 */
142 	ixp4xx_set_16bit_timing(ixpp, adev->pio_mode);
143 	udelay(5);
144 
145 	/* Transfer multiple of 2 bytes */
146 	if (rw == READ)
147 		for (i = 0; i < words; i++)
148 			buf16[i] = readw(mmio);
149 	else
150 		for (i = 0; i < words; i++)
151 			writew(buf16[i], mmio);
152 
153 	/* Transfer trailing 1 byte, if any. */
154 	if (unlikely(buflen & 0x01)) {
155 		u16 align_buf[1] = { 0 };
156 		unsigned char *trailing_buf = buf + buflen - 1;
157 
158 		if (rw == READ) {
159 			align_buf[0] = readw(mmio);
160 			memcpy(trailing_buf, align_buf, 1);
161 		} else {
162 			memcpy(align_buf, trailing_buf, 1);
163 			writew(align_buf[0], mmio);
164 		}
165 		words++;
166 	}
167 
168 	ixp4xx_set_8bit_timing(ixpp, adev->pio_mode);
169 	udelay(5);
170 
171 	spin_unlock_irqrestore(ap->lock, flags);
172 
173 	return words << 1;
174 }
175 
176 static struct scsi_host_template ixp4xx_sht = {
177 	ATA_PIO_SHT(DRV_NAME),
178 };
179 
180 static struct ata_port_operations ixp4xx_port_ops = {
181 	.inherits		= &ata_sff_port_ops,
182 	.sff_data_xfer		= ixp4xx_mmio_data_xfer,
183 	.cable_detect		= ata_cable_40wire,
184 	.set_piomode		= ixp4xx_set_piomode,
185 };
186 
187 static struct ata_port_info ixp4xx_port_info = {
188 	.flags		= ATA_FLAG_NO_ATAPI,
189 	.pio_mask	= ATA_PIO4,
190 	.port_ops	= &ixp4xx_port_ops,
191 };
192 
193 static void ixp4xx_setup_port(struct ata_port *ap,
194 			      struct ixp4xx_pata *ixpp,
195 			      unsigned long raw_cmd, unsigned long raw_ctl)
196 {
197 	struct ata_ioports *ioaddr = &ap->ioaddr;
198 
199 	raw_ctl += 0x06;
200 	ioaddr->cmd_addr	= ixpp->cmd;
201 	ioaddr->altstatus_addr	= ixpp->ctl + 0x06;
202 	ioaddr->ctl_addr	= ixpp->ctl + 0x06;
203 
204 	ata_sff_std_ports(ioaddr);
205 
206 	if (!IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) {
207 		/* adjust the addresses to handle the address swizzling of the
208 		 * ixp4xx in little endian mode.
209 		 */
210 
211 		*(unsigned long *)&ioaddr->data_addr		^= 0x02;
212 		*(unsigned long *)&ioaddr->cmd_addr		^= 0x03;
213 		*(unsigned long *)&ioaddr->altstatus_addr	^= 0x03;
214 		*(unsigned long *)&ioaddr->ctl_addr		^= 0x03;
215 		*(unsigned long *)&ioaddr->error_addr		^= 0x03;
216 		*(unsigned long *)&ioaddr->feature_addr		^= 0x03;
217 		*(unsigned long *)&ioaddr->nsect_addr		^= 0x03;
218 		*(unsigned long *)&ioaddr->lbal_addr		^= 0x03;
219 		*(unsigned long *)&ioaddr->lbam_addr		^= 0x03;
220 		*(unsigned long *)&ioaddr->lbah_addr		^= 0x03;
221 		*(unsigned long *)&ioaddr->device_addr		^= 0x03;
222 		*(unsigned long *)&ioaddr->status_addr		^= 0x03;
223 		*(unsigned long *)&ioaddr->command_addr		^= 0x03;
224 
225 		raw_cmd ^= 0x03;
226 		raw_ctl ^= 0x03;
227 	}
228 
229 	ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx", raw_cmd, raw_ctl);
230 }
231 
232 static int ixp4xx_pata_probe(struct platform_device *pdev)
233 {
234 	struct resource *cmd, *ctl;
235 	struct ata_port_info pi = ixp4xx_port_info;
236 	const struct ata_port_info *ppi[] = { &pi, NULL };
237 	struct device *dev = &pdev->dev;
238 	struct device_node *np = dev->of_node;
239 	struct ixp4xx_pata *ixpp;
240 	u32 csindex;
241 	int ret;
242 	int irq;
243 
244 	cmd = platform_get_resource(pdev, IORESOURCE_MEM, 0);
245 	ctl = platform_get_resource(pdev, IORESOURCE_MEM, 1);
246 
247 	if (!cmd || !ctl)
248 		return -EINVAL;
249 
250 	ixpp = devm_kzalloc(dev, sizeof(*ixpp), GFP_KERNEL);
251 	if (!ixpp)
252 		return -ENOMEM;
253 
254 	ixpp->rmap = syscon_node_to_regmap(np->parent);
255 	if (IS_ERR(ixpp->rmap))
256 		return dev_err_probe(dev, PTR_ERR(ixpp->rmap), "no regmap\n");
257 	/* Inspect our address to figure out what chipselect the CMD is on */
258 	ret = of_property_read_u32_index(np, "reg", 0, &csindex);
259 	if (ret)
260 		return dev_err_probe(dev, ret, "can't inspect CMD address\n");
261 	dev_info(dev, "using CS%d for PIO timing configuration\n", csindex);
262 	ixpp->cmd_csreg = csindex * IXP4XX_EXP_TIMING_STRIDE;
263 
264 	ixpp->host = ata_host_alloc_pinfo(dev, ppi, 1);
265 	if (!ixpp->host)
266 		return -ENOMEM;
267 	ixpp->host->private_data = ixpp;
268 
269 	ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
270 	if (ret)
271 		return ret;
272 
273 	ixpp->cmd = devm_ioremap_resource(dev, cmd);
274 	ixpp->ctl = devm_ioremap_resource(dev, ctl);
275 	if (IS_ERR(ixpp->cmd) || IS_ERR(ixpp->ctl))
276 		return -ENOMEM;
277 
278 	irq = platform_get_irq(pdev, 0);
279 	if (irq > 0)
280 		irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
281 	else if (irq < 0)
282 		return irq;
283 	else
284 		return -EINVAL;
285 
286 	/* Just one port to set up */
287 	ixp4xx_setup_port(ixpp->host->ports[0], ixpp, cmd->start, ctl->start);
288 
289 	ata_print_version_once(dev, DRV_VERSION);
290 
291 	return ata_host_activate(ixpp->host, irq, ata_sff_interrupt, 0, &ixp4xx_sht);
292 }
293 
294 static const struct of_device_id ixp4xx_pata_of_match[] = {
295 	{ .compatible = "intel,ixp4xx-compact-flash", },
296 	{ /* sentinel */ }
297 };
298 
299 static struct platform_driver ixp4xx_pata_platform_driver = {
300 	.driver	 = {
301 		.name   = DRV_NAME,
302 		.of_match_table = ixp4xx_pata_of_match,
303 	},
304 	.probe		= ixp4xx_pata_probe,
305 	.remove		= ata_platform_remove_one,
306 };
307 
308 module_platform_driver(ixp4xx_pata_platform_driver);
309 
310 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
311 MODULE_DESCRIPTION("low-level driver for ixp4xx Compact Flash PATA");
312 MODULE_LICENSE("GPL");
313 MODULE_VERSION(DRV_VERSION);
314 MODULE_ALIAS("platform:" DRV_NAME);
315