xref: /openbmc/linux/drivers/mtd/nand/raw/fsl_upm.c (revision f220d3eb)
1 /*
2  * Freescale UPM NAND driver.
3  *
4  * Copyright © 2007-2008  MontaVista Software, Inc.
5  *
6  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/delay.h>
17 #include <linux/mtd/rawnand.h>
18 #include <linux/mtd/nand_ecc.h>
19 #include <linux/mtd/partitions.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/of_address.h>
22 #include <linux/of_platform.h>
23 #include <linux/of_gpio.h>
24 #include <linux/io.h>
25 #include <linux/slab.h>
26 #include <asm/fsl_lbc.h>
27 
28 #define FSL_UPM_WAIT_RUN_PATTERN  0x1
29 #define FSL_UPM_WAIT_WRITE_BYTE   0x2
30 #define FSL_UPM_WAIT_WRITE_BUFFER 0x4
31 
32 struct fsl_upm_nand {
33 	struct device *dev;
34 	struct nand_chip chip;
35 	int last_ctrl;
36 	struct mtd_partition *parts;
37 	struct fsl_upm upm;
38 	uint8_t upm_addr_offset;
39 	uint8_t upm_cmd_offset;
40 	void __iomem *io_base;
41 	int rnb_gpio[NAND_MAX_CHIPS];
42 	uint32_t mchip_offsets[NAND_MAX_CHIPS];
43 	uint32_t mchip_count;
44 	uint32_t mchip_number;
45 	int chip_delay;
46 	uint32_t wait_flags;
47 };
48 
49 static inline struct fsl_upm_nand *to_fsl_upm_nand(struct mtd_info *mtdinfo)
50 {
51 	return container_of(mtd_to_nand(mtdinfo), struct fsl_upm_nand,
52 			    chip);
53 }
54 
55 static int fun_chip_ready(struct mtd_info *mtd)
56 {
57 	struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
58 
59 	if (gpio_get_value(fun->rnb_gpio[fun->mchip_number]))
60 		return 1;
61 
62 	dev_vdbg(fun->dev, "busy\n");
63 	return 0;
64 }
65 
66 static void fun_wait_rnb(struct fsl_upm_nand *fun)
67 {
68 	if (fun->rnb_gpio[fun->mchip_number] >= 0) {
69 		struct mtd_info *mtd = nand_to_mtd(&fun->chip);
70 		int cnt = 1000000;
71 
72 		while (--cnt && !fun_chip_ready(mtd))
73 			cpu_relax();
74 		if (!cnt)
75 			dev_err(fun->dev, "tired waiting for RNB\n");
76 	} else {
77 		ndelay(100);
78 	}
79 }
80 
81 static void fun_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
82 {
83 	struct nand_chip *chip = mtd_to_nand(mtd);
84 	struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
85 	u32 mar;
86 
87 	if (!(ctrl & fun->last_ctrl)) {
88 		fsl_upm_end_pattern(&fun->upm);
89 
90 		if (cmd == NAND_CMD_NONE)
91 			return;
92 
93 		fun->last_ctrl = ctrl & (NAND_ALE | NAND_CLE);
94 	}
95 
96 	if (ctrl & NAND_CTRL_CHANGE) {
97 		if (ctrl & NAND_ALE)
98 			fsl_upm_start_pattern(&fun->upm, fun->upm_addr_offset);
99 		else if (ctrl & NAND_CLE)
100 			fsl_upm_start_pattern(&fun->upm, fun->upm_cmd_offset);
101 	}
102 
103 	mar = (cmd << (32 - fun->upm.width)) |
104 		fun->mchip_offsets[fun->mchip_number];
105 	fsl_upm_run_pattern(&fun->upm, chip->IO_ADDR_R, mar);
106 
107 	if (fun->wait_flags & FSL_UPM_WAIT_RUN_PATTERN)
108 		fun_wait_rnb(fun);
109 }
110 
111 static void fun_select_chip(struct mtd_info *mtd, int mchip_nr)
112 {
113 	struct nand_chip *chip = mtd_to_nand(mtd);
114 	struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
115 
116 	if (mchip_nr == -1) {
117 		chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
118 	} else if (mchip_nr >= 0 && mchip_nr < NAND_MAX_CHIPS) {
119 		fun->mchip_number = mchip_nr;
120 		chip->IO_ADDR_R = fun->io_base + fun->mchip_offsets[mchip_nr];
121 		chip->IO_ADDR_W = chip->IO_ADDR_R;
122 	} else {
123 		BUG();
124 	}
125 }
126 
127 static uint8_t fun_read_byte(struct mtd_info *mtd)
128 {
129 	struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
130 
131 	return in_8(fun->chip.IO_ADDR_R);
132 }
133 
134 static void fun_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
135 {
136 	struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
137 	int i;
138 
139 	for (i = 0; i < len; i++)
140 		buf[i] = in_8(fun->chip.IO_ADDR_R);
141 }
142 
143 static void fun_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
144 {
145 	struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
146 	int i;
147 
148 	for (i = 0; i < len; i++) {
149 		out_8(fun->chip.IO_ADDR_W, buf[i]);
150 		if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BYTE)
151 			fun_wait_rnb(fun);
152 	}
153 	if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BUFFER)
154 		fun_wait_rnb(fun);
155 }
156 
157 static int fun_chip_init(struct fsl_upm_nand *fun,
158 			 const struct device_node *upm_np,
159 			 const struct resource *io_res)
160 {
161 	struct mtd_info *mtd = nand_to_mtd(&fun->chip);
162 	int ret;
163 	struct device_node *flash_np;
164 
165 	fun->chip.IO_ADDR_R = fun->io_base;
166 	fun->chip.IO_ADDR_W = fun->io_base;
167 	fun->chip.cmd_ctrl = fun_cmd_ctrl;
168 	fun->chip.chip_delay = fun->chip_delay;
169 	fun->chip.read_byte = fun_read_byte;
170 	fun->chip.read_buf = fun_read_buf;
171 	fun->chip.write_buf = fun_write_buf;
172 	fun->chip.ecc.mode = NAND_ECC_SOFT;
173 	fun->chip.ecc.algo = NAND_ECC_HAMMING;
174 	if (fun->mchip_count > 1)
175 		fun->chip.select_chip = fun_select_chip;
176 
177 	if (fun->rnb_gpio[0] >= 0)
178 		fun->chip.dev_ready = fun_chip_ready;
179 
180 	mtd->dev.parent = fun->dev;
181 
182 	flash_np = of_get_next_child(upm_np, NULL);
183 	if (!flash_np)
184 		return -ENODEV;
185 
186 	nand_set_flash_node(&fun->chip, flash_np);
187 	mtd->name = kasprintf(GFP_KERNEL, "0x%llx.%s", (u64)io_res->start,
188 			      flash_np->name);
189 	if (!mtd->name) {
190 		ret = -ENOMEM;
191 		goto err;
192 	}
193 
194 	ret = nand_scan(mtd, fun->mchip_count);
195 	if (ret)
196 		goto err;
197 
198 	ret = mtd_device_register(mtd, NULL, 0);
199 err:
200 	of_node_put(flash_np);
201 	if (ret)
202 		kfree(mtd->name);
203 	return ret;
204 }
205 
206 static int fun_probe(struct platform_device *ofdev)
207 {
208 	struct fsl_upm_nand *fun;
209 	struct resource io_res;
210 	const __be32 *prop;
211 	int rnb_gpio;
212 	int ret;
213 	int size;
214 	int i;
215 
216 	fun = kzalloc(sizeof(*fun), GFP_KERNEL);
217 	if (!fun)
218 		return -ENOMEM;
219 
220 	ret = of_address_to_resource(ofdev->dev.of_node, 0, &io_res);
221 	if (ret) {
222 		dev_err(&ofdev->dev, "can't get IO base\n");
223 		goto err1;
224 	}
225 
226 	ret = fsl_upm_find(io_res.start, &fun->upm);
227 	if (ret) {
228 		dev_err(&ofdev->dev, "can't find UPM\n");
229 		goto err1;
230 	}
231 
232 	prop = of_get_property(ofdev->dev.of_node, "fsl,upm-addr-offset",
233 			       &size);
234 	if (!prop || size != sizeof(uint32_t)) {
235 		dev_err(&ofdev->dev, "can't get UPM address offset\n");
236 		ret = -EINVAL;
237 		goto err1;
238 	}
239 	fun->upm_addr_offset = *prop;
240 
241 	prop = of_get_property(ofdev->dev.of_node, "fsl,upm-cmd-offset", &size);
242 	if (!prop || size != sizeof(uint32_t)) {
243 		dev_err(&ofdev->dev, "can't get UPM command offset\n");
244 		ret = -EINVAL;
245 		goto err1;
246 	}
247 	fun->upm_cmd_offset = *prop;
248 
249 	prop = of_get_property(ofdev->dev.of_node,
250 			       "fsl,upm-addr-line-cs-offsets", &size);
251 	if (prop && (size / sizeof(uint32_t)) > 0) {
252 		fun->mchip_count = size / sizeof(uint32_t);
253 		if (fun->mchip_count >= NAND_MAX_CHIPS) {
254 			dev_err(&ofdev->dev, "too much multiple chips\n");
255 			goto err1;
256 		}
257 		for (i = 0; i < fun->mchip_count; i++)
258 			fun->mchip_offsets[i] = be32_to_cpu(prop[i]);
259 	} else {
260 		fun->mchip_count = 1;
261 	}
262 
263 	for (i = 0; i < fun->mchip_count; i++) {
264 		fun->rnb_gpio[i] = -1;
265 		rnb_gpio = of_get_gpio(ofdev->dev.of_node, i);
266 		if (rnb_gpio >= 0) {
267 			ret = gpio_request(rnb_gpio, dev_name(&ofdev->dev));
268 			if (ret) {
269 				dev_err(&ofdev->dev,
270 					"can't request RNB gpio #%d\n", i);
271 				goto err2;
272 			}
273 			gpio_direction_input(rnb_gpio);
274 			fun->rnb_gpio[i] = rnb_gpio;
275 		} else if (rnb_gpio == -EINVAL) {
276 			dev_err(&ofdev->dev, "RNB gpio #%d is invalid\n", i);
277 			goto err2;
278 		}
279 	}
280 
281 	prop = of_get_property(ofdev->dev.of_node, "chip-delay", NULL);
282 	if (prop)
283 		fun->chip_delay = be32_to_cpup(prop);
284 	else
285 		fun->chip_delay = 50;
286 
287 	prop = of_get_property(ofdev->dev.of_node, "fsl,upm-wait-flags", &size);
288 	if (prop && size == sizeof(uint32_t))
289 		fun->wait_flags = be32_to_cpup(prop);
290 	else
291 		fun->wait_flags = FSL_UPM_WAIT_RUN_PATTERN |
292 				  FSL_UPM_WAIT_WRITE_BYTE;
293 
294 	fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
295 					    resource_size(&io_res));
296 	if (!fun->io_base) {
297 		ret = -ENOMEM;
298 		goto err2;
299 	}
300 
301 	fun->dev = &ofdev->dev;
302 	fun->last_ctrl = NAND_CLE;
303 
304 	ret = fun_chip_init(fun, ofdev->dev.of_node, &io_res);
305 	if (ret)
306 		goto err2;
307 
308 	dev_set_drvdata(&ofdev->dev, fun);
309 
310 	return 0;
311 err2:
312 	for (i = 0; i < fun->mchip_count; i++) {
313 		if (fun->rnb_gpio[i] < 0)
314 			break;
315 		gpio_free(fun->rnb_gpio[i]);
316 	}
317 err1:
318 	kfree(fun);
319 
320 	return ret;
321 }
322 
323 static int fun_remove(struct platform_device *ofdev)
324 {
325 	struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
326 	struct mtd_info *mtd = nand_to_mtd(&fun->chip);
327 	int i;
328 
329 	nand_release(mtd);
330 	kfree(mtd->name);
331 
332 	for (i = 0; i < fun->mchip_count; i++) {
333 		if (fun->rnb_gpio[i] < 0)
334 			break;
335 		gpio_free(fun->rnb_gpio[i]);
336 	}
337 
338 	kfree(fun);
339 
340 	return 0;
341 }
342 
343 static const struct of_device_id of_fun_match[] = {
344 	{ .compatible = "fsl,upm-nand" },
345 	{},
346 };
347 MODULE_DEVICE_TABLE(of, of_fun_match);
348 
349 static struct platform_driver of_fun_driver = {
350 	.driver = {
351 		.name = "fsl,upm-nand",
352 		.of_match_table = of_fun_match,
353 	},
354 	.probe		= fun_probe,
355 	.remove		= fun_remove,
356 };
357 
358 module_platform_driver(of_fun_driver);
359 
360 MODULE_LICENSE("GPL");
361 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
362 MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
363 		   "LocalBus User-Programmable Machine");
364