xref: /openbmc/linux/drivers/mtd/nand/raw/fsl_upm.c (revision 453431a5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Freescale UPM NAND driver.
4  *
5  * Copyright © 2007-2008  MontaVista Software, Inc.
6  *
7  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/delay.h>
13 #include <linux/mtd/rawnand.h>
14 #include <linux/mtd/nand_ecc.h>
15 #include <linux/mtd/partitions.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/of_address.h>
18 #include <linux/of_platform.h>
19 #include <linux/of_gpio.h>
20 #include <linux/io.h>
21 #include <linux/slab.h>
22 #include <asm/fsl_lbc.h>
23 
24 #define FSL_UPM_WAIT_RUN_PATTERN  0x1
25 #define FSL_UPM_WAIT_WRITE_BYTE   0x2
26 #define FSL_UPM_WAIT_WRITE_BUFFER 0x4
27 
28 struct fsl_upm_nand {
29 	struct device *dev;
30 	struct nand_chip chip;
31 	int last_ctrl;
32 	struct mtd_partition *parts;
33 	struct fsl_upm upm;
34 	uint8_t upm_addr_offset;
35 	uint8_t upm_cmd_offset;
36 	void __iomem *io_base;
37 	int rnb_gpio[NAND_MAX_CHIPS];
38 	uint32_t mchip_offsets[NAND_MAX_CHIPS];
39 	uint32_t mchip_count;
40 	uint32_t mchip_number;
41 	int chip_delay;
42 	uint32_t wait_flags;
43 };
44 
45 static inline struct fsl_upm_nand *to_fsl_upm_nand(struct mtd_info *mtdinfo)
46 {
47 	return container_of(mtd_to_nand(mtdinfo), struct fsl_upm_nand,
48 			    chip);
49 }
50 
51 static int fun_chip_ready(struct nand_chip *chip)
52 {
53 	struct fsl_upm_nand *fun = to_fsl_upm_nand(nand_to_mtd(chip));
54 
55 	if (gpio_get_value(fun->rnb_gpio[fun->mchip_number]))
56 		return 1;
57 
58 	dev_vdbg(fun->dev, "busy\n");
59 	return 0;
60 }
61 
62 static void fun_wait_rnb(struct fsl_upm_nand *fun)
63 {
64 	if (fun->rnb_gpio[fun->mchip_number] >= 0) {
65 		struct mtd_info *mtd = nand_to_mtd(&fun->chip);
66 		int cnt = 1000000;
67 
68 		while (--cnt && !fun_chip_ready(&fun->chip))
69 			cpu_relax();
70 		if (!cnt)
71 			dev_err(fun->dev, "tired waiting for RNB\n");
72 	} else {
73 		ndelay(100);
74 	}
75 }
76 
77 static void fun_cmd_ctrl(struct nand_chip *chip, int cmd, unsigned int ctrl)
78 {
79 	struct fsl_upm_nand *fun = to_fsl_upm_nand(nand_to_mtd(chip));
80 	u32 mar;
81 
82 	if (!(ctrl & fun->last_ctrl)) {
83 		fsl_upm_end_pattern(&fun->upm);
84 
85 		if (cmd == NAND_CMD_NONE)
86 			return;
87 
88 		fun->last_ctrl = ctrl & (NAND_ALE | NAND_CLE);
89 	}
90 
91 	if (ctrl & NAND_CTRL_CHANGE) {
92 		if (ctrl & NAND_ALE)
93 			fsl_upm_start_pattern(&fun->upm, fun->upm_addr_offset);
94 		else if (ctrl & NAND_CLE)
95 			fsl_upm_start_pattern(&fun->upm, fun->upm_cmd_offset);
96 	}
97 
98 	mar = (cmd << (32 - fun->upm.width)) |
99 		fun->mchip_offsets[fun->mchip_number];
100 	fsl_upm_run_pattern(&fun->upm, chip->legacy.IO_ADDR_R, mar);
101 
102 	if (fun->wait_flags & FSL_UPM_WAIT_RUN_PATTERN)
103 		fun_wait_rnb(fun);
104 }
105 
106 static void fun_select_chip(struct nand_chip *chip, int mchip_nr)
107 {
108 	struct fsl_upm_nand *fun = to_fsl_upm_nand(nand_to_mtd(chip));
109 
110 	if (mchip_nr == -1) {
111 		chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
112 	} else if (mchip_nr >= 0 && mchip_nr < NAND_MAX_CHIPS) {
113 		fun->mchip_number = mchip_nr;
114 		chip->legacy.IO_ADDR_R = fun->io_base + fun->mchip_offsets[mchip_nr];
115 		chip->legacy.IO_ADDR_W = chip->legacy.IO_ADDR_R;
116 	} else {
117 		BUG();
118 	}
119 }
120 
121 static uint8_t fun_read_byte(struct nand_chip *chip)
122 {
123 	struct fsl_upm_nand *fun = to_fsl_upm_nand(nand_to_mtd(chip));
124 
125 	return in_8(fun->chip.legacy.IO_ADDR_R);
126 }
127 
128 static void fun_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
129 {
130 	struct fsl_upm_nand *fun = to_fsl_upm_nand(nand_to_mtd(chip));
131 	int i;
132 
133 	for (i = 0; i < len; i++)
134 		buf[i] = in_8(fun->chip.legacy.IO_ADDR_R);
135 }
136 
137 static void fun_write_buf(struct nand_chip *chip, const uint8_t *buf, int len)
138 {
139 	struct fsl_upm_nand *fun = to_fsl_upm_nand(nand_to_mtd(chip));
140 	int i;
141 
142 	for (i = 0; i < len; i++) {
143 		out_8(fun->chip.legacy.IO_ADDR_W, buf[i]);
144 		if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BYTE)
145 			fun_wait_rnb(fun);
146 	}
147 	if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BUFFER)
148 		fun_wait_rnb(fun);
149 }
150 
151 static int fun_chip_init(struct fsl_upm_nand *fun,
152 			 const struct device_node *upm_np,
153 			 const struct resource *io_res)
154 {
155 	struct mtd_info *mtd = nand_to_mtd(&fun->chip);
156 	int ret;
157 	struct device_node *flash_np;
158 
159 	fun->chip.legacy.IO_ADDR_R = fun->io_base;
160 	fun->chip.legacy.IO_ADDR_W = fun->io_base;
161 	fun->chip.legacy.cmd_ctrl = fun_cmd_ctrl;
162 	fun->chip.legacy.chip_delay = fun->chip_delay;
163 	fun->chip.legacy.read_byte = fun_read_byte;
164 	fun->chip.legacy.read_buf = fun_read_buf;
165 	fun->chip.legacy.write_buf = fun_write_buf;
166 	fun->chip.ecc.mode = NAND_ECC_SOFT;
167 	fun->chip.ecc.algo = NAND_ECC_HAMMING;
168 	if (fun->mchip_count > 1)
169 		fun->chip.legacy.select_chip = fun_select_chip;
170 
171 	if (fun->rnb_gpio[0] >= 0)
172 		fun->chip.legacy.dev_ready = fun_chip_ready;
173 
174 	mtd->dev.parent = fun->dev;
175 
176 	flash_np = of_get_next_child(upm_np, NULL);
177 	if (!flash_np)
178 		return -ENODEV;
179 
180 	nand_set_flash_node(&fun->chip, flash_np);
181 	mtd->name = kasprintf(GFP_KERNEL, "0x%llx.%pOFn", (u64)io_res->start,
182 			      flash_np);
183 	if (!mtd->name) {
184 		ret = -ENOMEM;
185 		goto err;
186 	}
187 
188 	ret = nand_scan(&fun->chip, fun->mchip_count);
189 	if (ret)
190 		goto err;
191 
192 	ret = mtd_device_register(mtd, NULL, 0);
193 err:
194 	of_node_put(flash_np);
195 	if (ret)
196 		kfree(mtd->name);
197 	return ret;
198 }
199 
200 static int fun_probe(struct platform_device *ofdev)
201 {
202 	struct fsl_upm_nand *fun;
203 	struct resource io_res;
204 	const __be32 *prop;
205 	int rnb_gpio;
206 	int ret;
207 	int size;
208 	int i;
209 
210 	fun = kzalloc(sizeof(*fun), GFP_KERNEL);
211 	if (!fun)
212 		return -ENOMEM;
213 
214 	ret = of_address_to_resource(ofdev->dev.of_node, 0, &io_res);
215 	if (ret) {
216 		dev_err(&ofdev->dev, "can't get IO base\n");
217 		goto err1;
218 	}
219 
220 	ret = fsl_upm_find(io_res.start, &fun->upm);
221 	if (ret) {
222 		dev_err(&ofdev->dev, "can't find UPM\n");
223 		goto err1;
224 	}
225 
226 	prop = of_get_property(ofdev->dev.of_node, "fsl,upm-addr-offset",
227 			       &size);
228 	if (!prop || size != sizeof(uint32_t)) {
229 		dev_err(&ofdev->dev, "can't get UPM address offset\n");
230 		ret = -EINVAL;
231 		goto err1;
232 	}
233 	fun->upm_addr_offset = *prop;
234 
235 	prop = of_get_property(ofdev->dev.of_node, "fsl,upm-cmd-offset", &size);
236 	if (!prop || size != sizeof(uint32_t)) {
237 		dev_err(&ofdev->dev, "can't get UPM command offset\n");
238 		ret = -EINVAL;
239 		goto err1;
240 	}
241 	fun->upm_cmd_offset = *prop;
242 
243 	prop = of_get_property(ofdev->dev.of_node,
244 			       "fsl,upm-addr-line-cs-offsets", &size);
245 	if (prop && (size / sizeof(uint32_t)) > 0) {
246 		fun->mchip_count = size / sizeof(uint32_t);
247 		if (fun->mchip_count >= NAND_MAX_CHIPS) {
248 			dev_err(&ofdev->dev, "too much multiple chips\n");
249 			goto err1;
250 		}
251 		for (i = 0; i < fun->mchip_count; i++)
252 			fun->mchip_offsets[i] = be32_to_cpu(prop[i]);
253 	} else {
254 		fun->mchip_count = 1;
255 	}
256 
257 	for (i = 0; i < fun->mchip_count; i++) {
258 		fun->rnb_gpio[i] = -1;
259 		rnb_gpio = of_get_gpio(ofdev->dev.of_node, i);
260 		if (rnb_gpio >= 0) {
261 			ret = gpio_request(rnb_gpio, dev_name(&ofdev->dev));
262 			if (ret) {
263 				dev_err(&ofdev->dev,
264 					"can't request RNB gpio #%d\n", i);
265 				goto err2;
266 			}
267 			gpio_direction_input(rnb_gpio);
268 			fun->rnb_gpio[i] = rnb_gpio;
269 		} else if (rnb_gpio == -EINVAL) {
270 			dev_err(&ofdev->dev, "RNB gpio #%d is invalid\n", i);
271 			goto err2;
272 		}
273 	}
274 
275 	prop = of_get_property(ofdev->dev.of_node, "chip-delay", NULL);
276 	if (prop)
277 		fun->chip_delay = be32_to_cpup(prop);
278 	else
279 		fun->chip_delay = 50;
280 
281 	prop = of_get_property(ofdev->dev.of_node, "fsl,upm-wait-flags", &size);
282 	if (prop && size == sizeof(uint32_t))
283 		fun->wait_flags = be32_to_cpup(prop);
284 	else
285 		fun->wait_flags = FSL_UPM_WAIT_RUN_PATTERN |
286 				  FSL_UPM_WAIT_WRITE_BYTE;
287 
288 	fun->io_base = devm_ioremap(&ofdev->dev, io_res.start,
289 					    resource_size(&io_res));
290 	if (!fun->io_base) {
291 		ret = -ENOMEM;
292 		goto err2;
293 	}
294 
295 	fun->dev = &ofdev->dev;
296 	fun->last_ctrl = NAND_CLE;
297 
298 	ret = fun_chip_init(fun, ofdev->dev.of_node, &io_res);
299 	if (ret)
300 		goto err2;
301 
302 	dev_set_drvdata(&ofdev->dev, fun);
303 
304 	return 0;
305 err2:
306 	for (i = 0; i < fun->mchip_count; i++) {
307 		if (fun->rnb_gpio[i] < 0)
308 			break;
309 		gpio_free(fun->rnb_gpio[i]);
310 	}
311 err1:
312 	kfree(fun);
313 
314 	return ret;
315 }
316 
317 static int fun_remove(struct platform_device *ofdev)
318 {
319 	struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
320 	struct nand_chip *chip = &fun->chip;
321 	struct mtd_info *mtd = nand_to_mtd(chip);
322 	int ret, i;
323 
324 	ret = mtd_device_unregister(mtd);
325 	WARN_ON(ret);
326 	nand_cleanup(chip);
327 	kfree(mtd->name);
328 
329 	for (i = 0; i < fun->mchip_count; i++) {
330 		if (fun->rnb_gpio[i] < 0)
331 			break;
332 		gpio_free(fun->rnb_gpio[i]);
333 	}
334 
335 	kfree(fun);
336 
337 	return 0;
338 }
339 
340 static const struct of_device_id of_fun_match[] = {
341 	{ .compatible = "fsl,upm-nand" },
342 	{},
343 };
344 MODULE_DEVICE_TABLE(of, of_fun_match);
345 
346 static struct platform_driver of_fun_driver = {
347 	.driver = {
348 		.name = "fsl,upm-nand",
349 		.of_match_table = of_fun_match,
350 	},
351 	.probe		= fun_probe,
352 	.remove		= fun_remove,
353 };
354 
355 module_platform_driver(of_fun_driver);
356 
357 MODULE_LICENSE("GPL");
358 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
359 MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
360 		   "LocalBus User-Programmable Machine");
361