xref: /linux/drivers/mtd/maps/physmap-core.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Normal mappings of chips in physical memory
4  *
5  * Copyright (C) 2003 MontaVista Software Inc.
6  * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
7  *
8  * 031022 - [jsun] add run-time configure and partition setup
9  *
10  * Device tree support:
11  *    Copyright (C) 2006 MontaVista Software Inc.
12  *    Author: Vitaly Wool <vwool@ru.mvista.com>
13  *
14  *    Revised to handle newer style flash binding by:
15  *    Copyright (C) 2007 David Gibson, IBM Corporation.
16  *
17  * GPIO address extension:
18  *    Handle the case where a flash device is mostly addressed using physical
19  *    line and supplemented by GPIOs.  This way you can hook up say a 8MiB flash
20  *    to a 2MiB memory range and use the GPIOs to select a particular range.
21  *
22  *    Copyright © 2000 Nicolas Pitre <nico@cam.org>
23  *    Copyright © 2005-2009 Analog Devices Inc.
24  */
25 
26 #include <linux/module.h>
27 #include <linux/types.h>
28 #include <linux/kernel.h>
29 #include <linux/init.h>
30 #include <linux/slab.h>
31 #include <linux/device.h>
32 #include <linux/platform_device.h>
33 #include <linux/property.h>
34 #include <linux/mtd/mtd.h>
35 #include <linux/mtd/map.h>
36 #include <linux/mtd/partitions.h>
37 #include <linux/mtd/physmap.h>
38 #include <linux/mtd/concat.h>
39 #include <linux/mtd/cfi_endian.h>
40 #include <linux/io.h>
41 #include <linux/of.h>
42 #include <linux/pm_runtime.h>
43 #include <linux/gpio/consumer.h>
44 
45 #include "physmap-bt1-rom.h"
46 #include "physmap-gemini.h"
47 #include "physmap-ixp4xx.h"
48 #include "physmap-versatile.h"
49 
50 struct physmap_flash_info {
51 	unsigned int		nmaps;
52 	struct mtd_info		**mtds;
53 	struct mtd_info		*cmtd;
54 	struct map_info		*maps;
55 	spinlock_t		vpp_lock;
56 	int			vpp_refcnt;
57 	const char		*probe_type;
58 	const char * const	*part_types;
59 	unsigned int		nparts;
60 	const struct mtd_partition *parts;
61 	struct gpio_descs	*gpios;
62 	unsigned int		gpio_values;
63 	unsigned int		win_order;
64 };
65 
66 static void physmap_flash_remove(struct platform_device *dev)
67 {
68 	struct physmap_flash_info *info;
69 	struct physmap_flash_data *physmap_data;
70 	int i;
71 
72 	info = platform_get_drvdata(dev);
73 
74 	if (info->cmtd) {
75 		WARN_ON(mtd_device_unregister(info->cmtd));
76 
77 		if (info->cmtd != info->mtds[0])
78 			mtd_concat_destroy(info->cmtd);
79 	}
80 
81 	for (i = 0; i < info->nmaps; i++) {
82 		if (info->mtds[i])
83 			map_destroy(info->mtds[i]);
84 	}
85 
86 	physmap_data = dev_get_platdata(&dev->dev);
87 	if (physmap_data && physmap_data->exit)
88 		physmap_data->exit(dev);
89 
90 	pm_runtime_put(&dev->dev);
91 	pm_runtime_disable(&dev->dev);
92 }
93 
94 static void physmap_set_vpp(struct map_info *map, int state)
95 {
96 	struct platform_device *pdev;
97 	struct physmap_flash_data *physmap_data;
98 	struct physmap_flash_info *info;
99 	unsigned long flags;
100 
101 	pdev = (struct platform_device *)map->map_priv_1;
102 	physmap_data = dev_get_platdata(&pdev->dev);
103 
104 	if (!physmap_data->set_vpp)
105 		return;
106 
107 	info = platform_get_drvdata(pdev);
108 
109 	spin_lock_irqsave(&info->vpp_lock, flags);
110 	if (state) {
111 		if (++info->vpp_refcnt == 1)    /* first nested 'on' */
112 			physmap_data->set_vpp(pdev, 1);
113 	} else {
114 		if (--info->vpp_refcnt == 0)    /* last nested 'off' */
115 			physmap_data->set_vpp(pdev, 0);
116 	}
117 	spin_unlock_irqrestore(&info->vpp_lock, flags);
118 }
119 
120 #if IS_ENABLED(CONFIG_MTD_PHYSMAP_GPIO_ADDR)
121 static void physmap_set_addr_gpios(struct physmap_flash_info *info,
122 				   unsigned long ofs)
123 {
124 	unsigned int i;
125 
126 	ofs >>= info->win_order;
127 	if (info->gpio_values == ofs)
128 		return;
129 
130 	for (i = 0; i < info->gpios->ndescs; i++) {
131 		if ((BIT(i) & ofs) == (BIT(i) & info->gpio_values))
132 			continue;
133 
134 		gpiod_set_value(info->gpios->desc[i], !!(BIT(i) & ofs));
135 	}
136 
137 	info->gpio_values = ofs;
138 }
139 
140 #define win_mask(order)		(BIT(order) - 1)
141 
142 static map_word physmap_addr_gpios_read(struct map_info *map,
143 					unsigned long ofs)
144 {
145 	struct platform_device *pdev;
146 	struct physmap_flash_info *info;
147 	map_word mw;
148 	u16 word;
149 
150 	pdev = (struct platform_device *)map->map_priv_1;
151 	info = platform_get_drvdata(pdev);
152 	physmap_set_addr_gpios(info, ofs);
153 
154 	word = readw(map->virt + (ofs & win_mask(info->win_order)));
155 	mw.x[0] = word;
156 	return mw;
157 }
158 
159 static void physmap_addr_gpios_copy_from(struct map_info *map, void *buf,
160 					 unsigned long ofs, ssize_t len)
161 {
162 	struct platform_device *pdev;
163 	struct physmap_flash_info *info;
164 
165 	pdev = (struct platform_device *)map->map_priv_1;
166 	info = platform_get_drvdata(pdev);
167 
168 	while (len) {
169 		unsigned int winofs = ofs & win_mask(info->win_order);
170 		unsigned int chunklen = min_t(unsigned int, len,
171 					      BIT(info->win_order) - winofs);
172 
173 		physmap_set_addr_gpios(info, ofs);
174 		memcpy_fromio(buf, map->virt + winofs, chunklen);
175 		len -= chunklen;
176 		buf += chunklen;
177 		ofs += chunklen;
178 	}
179 }
180 
181 static void physmap_addr_gpios_write(struct map_info *map, map_word mw,
182 				     unsigned long ofs)
183 {
184 	struct platform_device *pdev;
185 	struct physmap_flash_info *info;
186 	u16 word;
187 
188 	pdev = (struct platform_device *)map->map_priv_1;
189 	info = platform_get_drvdata(pdev);
190 	physmap_set_addr_gpios(info, ofs);
191 
192 	word = mw.x[0];
193 	writew(word, map->virt + (ofs & win_mask(info->win_order)));
194 }
195 
196 static void physmap_addr_gpios_copy_to(struct map_info *map, unsigned long ofs,
197 				       const void *buf, ssize_t len)
198 {
199 	struct platform_device *pdev;
200 	struct physmap_flash_info *info;
201 
202 	pdev = (struct platform_device *)map->map_priv_1;
203 	info = platform_get_drvdata(pdev);
204 
205 	while (len) {
206 		unsigned int winofs = ofs & win_mask(info->win_order);
207 		unsigned int chunklen = min_t(unsigned int, len,
208 					      BIT(info->win_order) - winofs);
209 
210 		physmap_set_addr_gpios(info, ofs);
211 		memcpy_toio(map->virt + winofs, buf, chunklen);
212 		len -= chunklen;
213 		buf += chunklen;
214 		ofs += chunklen;
215 	}
216 }
217 
218 static int physmap_addr_gpios_map_init(struct map_info *map)
219 {
220 	map->phys = NO_XIP;
221 	map->read = physmap_addr_gpios_read;
222 	map->copy_from = physmap_addr_gpios_copy_from;
223 	map->write = physmap_addr_gpios_write;
224 	map->copy_to = physmap_addr_gpios_copy_to;
225 
226 	return 0;
227 }
228 #else
229 static int physmap_addr_gpios_map_init(struct map_info *map)
230 {
231 	return -ENOTSUPP;
232 }
233 #endif
234 
235 #if IS_ENABLED(CONFIG_MTD_PHYSMAP_OF)
236 static const struct of_device_id of_flash_match[] = {
237 	{
238 		.compatible = "cfi-flash",
239 		.data = "cfi_probe",
240 	},
241 	{
242 		/*
243 		 * FIXME: JEDEC chips can't be safely and reliably
244 		 * probed, although the mtd code gets it right in
245 		 * practice most of the time.  We should use the
246 		 * vendor and device ids specified by the binding to
247 		 * bypass the heuristic probe code, but the mtd layer
248 		 * provides, at present, no interface for doing so
249 		 * :(.
250 		 */
251 		.compatible = "jedec-flash",
252 		.data = "jedec_probe",
253 	},
254 	{
255 		.compatible = "mtd-ram",
256 		.data = "map_ram",
257 	},
258 	{
259 		.compatible = "mtd-rom",
260 		.data = "map_rom",
261 	},
262 	{
263 		.type = "rom",
264 		.compatible = "direct-mapped"
265 	},
266 	{ /* sentinel */ },
267 };
268 MODULE_DEVICE_TABLE(of, of_flash_match);
269 
270 static const char * const of_default_part_probes[] = {
271 	"cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL
272 };
273 
274 static const char * const *of_get_part_probes(struct platform_device *dev)
275 {
276 	struct device_node *dp = dev->dev.of_node;
277 	const char **res;
278 	int count;
279 
280 	count = of_property_count_strings(dp, "linux,part-probe");
281 	if (count < 0)
282 		return of_default_part_probes;
283 
284 	res = devm_kcalloc(&dev->dev, count + 1, sizeof(*res), GFP_KERNEL);
285 	if (!res)
286 		return NULL;
287 
288 	count = of_property_read_string_array(dp, "linux,part-probe", res,
289 					      count);
290 	if (count < 0)
291 		return NULL;
292 
293 	return res;
294 }
295 
296 static const char *of_select_probe_type(struct platform_device *dev)
297 {
298 	struct device_node *dp = dev->dev.of_node;
299 	const char *probe_type;
300 
301 	probe_type = device_get_match_data(&dev->dev);
302 	if (probe_type)
303 		return probe_type;
304 
305 	dev_warn(&dev->dev,
306 		 "Device tree uses obsolete \"direct-mapped\" flash binding\n");
307 
308 	of_property_read_string(dp, "probe-type", &probe_type);
309 	if (!probe_type)
310 		return NULL;
311 
312 	if (!strcmp(probe_type, "CFI")) {
313 		probe_type = "cfi_probe";
314 	} else if (!strcmp(probe_type, "JEDEC")) {
315 		probe_type = "jedec_probe";
316 	} else if (!strcmp(probe_type, "ROM")) {
317 		probe_type = "map_rom";
318 	} else {
319 		dev_warn(&dev->dev,
320 			 "obsolete_probe: don't know probe type '%s', mapping as rom\n",
321 			 probe_type);
322 		probe_type = "map_rom";
323 	}
324 
325 	return probe_type;
326 }
327 
328 static int physmap_flash_of_init(struct platform_device *dev)
329 {
330 	struct physmap_flash_info *info = platform_get_drvdata(dev);
331 	struct device_node *dp = dev->dev.of_node;
332 	const char *mtd_name = NULL;
333 	int err, swap = 0;
334 	bool map_indirect;
335 	unsigned int i;
336 	u32 bankwidth;
337 
338 	if (!dp)
339 		return -EINVAL;
340 
341 	info->probe_type = of_select_probe_type(dev);
342 
343 	info->part_types = of_get_part_probes(dev);
344 	if (!info->part_types)
345 		return -ENOMEM;
346 
347 	of_property_read_string(dp, "linux,mtd-name", &mtd_name);
348 
349 	map_indirect = of_property_read_bool(dp, "no-unaligned-direct-access");
350 
351 	err = of_property_read_u32(dp, "bank-width", &bankwidth);
352 	if (err) {
353 		dev_err(&dev->dev, "Can't get bank width from device tree\n");
354 		return err;
355 	}
356 
357 	if (of_property_read_bool(dp, "big-endian"))
358 		swap = CFI_BIG_ENDIAN;
359 	else if (of_property_read_bool(dp, "little-endian"))
360 		swap = CFI_LITTLE_ENDIAN;
361 
362 	for (i = 0; i < info->nmaps; i++) {
363 		info->maps[i].name = mtd_name;
364 		info->maps[i].swap = swap;
365 		info->maps[i].bankwidth = bankwidth;
366 		info->maps[i].device_node = dp;
367 
368 		err = of_flash_probe_bt1_rom(dev, dp, &info->maps[i]);
369 		if (err)
370 			return err;
371 
372 		err = of_flash_probe_gemini(dev, dp, &info->maps[i]);
373 		if (err)
374 			return err;
375 
376 		err = of_flash_probe_ixp4xx(dev, dp, &info->maps[i]);
377 		if (err)
378 			return err;
379 
380 		err = of_flash_probe_versatile(dev, dp, &info->maps[i]);
381 		if (err)
382 			return err;
383 
384 		/*
385 		 * On some platforms (e.g. MPC5200) a direct 1:1 mapping
386 		 * may cause problems with JFFS2 usage, as the local bus (LPB)
387 		 * doesn't support unaligned accesses as implemented in the
388 		 * JFFS2 code via memcpy(). By setting NO_XIP, the
389 		 * flash will not be exposed directly to the MTD users
390 		 * (e.g. JFFS2) any more.
391 		 */
392 		if (map_indirect)
393 			info->maps[i].phys = NO_XIP;
394 	}
395 
396 	return 0;
397 }
398 #else /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
399 #define of_flash_match NULL
400 
401 static int physmap_flash_of_init(struct platform_device *dev)
402 {
403 	return -ENOTSUPP;
404 }
405 #endif /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
406 
407 static const char * const rom_probe_types[] = {
408 	"cfi_probe", "jedec_probe", "qinfo_probe", "map_rom",
409 };
410 
411 static const char * const part_probe_types[] = {
412 	"cmdlinepart", "RedBoot", "afs", NULL
413 };
414 
415 static int physmap_flash_pdata_init(struct platform_device *dev)
416 {
417 	struct physmap_flash_info *info = platform_get_drvdata(dev);
418 	struct physmap_flash_data *physmap_data;
419 	unsigned int i;
420 	int err;
421 
422 	physmap_data = dev_get_platdata(&dev->dev);
423 	if (!physmap_data)
424 		return -EINVAL;
425 
426 	info->probe_type = physmap_data->probe_type;
427 	info->part_types = physmap_data->part_probe_types ? : part_probe_types;
428 	info->parts = physmap_data->parts;
429 	info->nparts = physmap_data->nr_parts;
430 
431 	if (physmap_data->init) {
432 		err = physmap_data->init(dev);
433 		if (err)
434 			return err;
435 	}
436 
437 	for (i = 0; i < info->nmaps; i++) {
438 		info->maps[i].bankwidth = physmap_data->width;
439 		info->maps[i].pfow_base = physmap_data->pfow_base;
440 		info->maps[i].set_vpp = physmap_set_vpp;
441 	}
442 
443 	return 0;
444 }
445 
446 static int physmap_flash_probe(struct platform_device *dev)
447 {
448 	struct physmap_flash_info *info;
449 	int err = 0;
450 	int i;
451 
452 	if (!dev->dev.of_node && !dev_get_platdata(&dev->dev))
453 		return -EINVAL;
454 
455 	info = devm_kzalloc(&dev->dev, sizeof(*info), GFP_KERNEL);
456 	if (!info)
457 		return -ENOMEM;
458 
459 	while (platform_get_resource(dev, IORESOURCE_MEM, info->nmaps))
460 		info->nmaps++;
461 
462 	if (!info->nmaps)
463 		return -ENODEV;
464 
465 	info->maps = devm_kzalloc(&dev->dev,
466 				  sizeof(*info->maps) * info->nmaps,
467 				  GFP_KERNEL);
468 	if (!info->maps)
469 		return -ENOMEM;
470 
471 	info->mtds = devm_kzalloc(&dev->dev,
472 				  sizeof(*info->mtds) * info->nmaps,
473 				  GFP_KERNEL);
474 	if (!info->mtds)
475 		return -ENOMEM;
476 
477 	platform_set_drvdata(dev, info);
478 
479 	info->gpios = devm_gpiod_get_array_optional(&dev->dev, "addr",
480 						    GPIOD_OUT_LOW);
481 	if (IS_ERR(info->gpios))
482 		return PTR_ERR(info->gpios);
483 
484 	if (info->gpios && info->nmaps > 1) {
485 		dev_err(&dev->dev, "addr-gpios only supported for nmaps == 1\n");
486 		return -EINVAL;
487 	}
488 
489 	pm_runtime_enable(&dev->dev);
490 	pm_runtime_get_sync(&dev->dev);
491 
492 	if (dev->dev.of_node)
493 		err = physmap_flash_of_init(dev);
494 	else
495 		err = physmap_flash_pdata_init(dev);
496 
497 	if (err) {
498 		pm_runtime_put(&dev->dev);
499 		pm_runtime_disable(&dev->dev);
500 		return err;
501 	}
502 
503 	for (i = 0; i < info->nmaps; i++) {
504 		struct resource *res;
505 
506 		info->maps[i].virt = devm_platform_get_and_ioremap_resource(dev, i, &res);
507 		if (IS_ERR(info->maps[i].virt)) {
508 			err = PTR_ERR(info->maps[i].virt);
509 			goto err_out;
510 		}
511 
512 		dev_notice(&dev->dev, "physmap platform flash device: %pR\n",
513 			   res);
514 
515 		if (!info->maps[i].name)
516 			info->maps[i].name = dev_name(&dev->dev);
517 
518 		if (!info->maps[i].phys)
519 			info->maps[i].phys = res->start;
520 
521 		info->win_order = fls64(resource_size(res)) - 1;
522 		info->maps[i].size = BIT(info->win_order +
523 					 (info->gpios ?
524 					  info->gpios->ndescs : 0));
525 
526 		info->maps[i].map_priv_1 = (unsigned long)dev;
527 
528 		if (info->gpios) {
529 			err = physmap_addr_gpios_map_init(&info->maps[i]);
530 			if (err)
531 				goto err_out;
532 		}
533 
534 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
535 		/*
536 		 * Only use the simple_map implementation if map hooks are not
537 		 * implemented. Since map->read() is mandatory checking for its
538 		 * presence is enough.
539 		 */
540 		if (!info->maps[i].read)
541 			simple_map_init(&info->maps[i]);
542 #else
543 		simple_map_init(&info->maps[i]);
544 #endif
545 
546 		if (info->probe_type) {
547 			info->mtds[i] = do_map_probe(info->probe_type,
548 						     &info->maps[i]);
549 
550 			/* Fall back to mapping region as ROM */
551 			if (!info->mtds[i] && IS_ENABLED(CONFIG_MTD_ROM) &&
552 			    strcmp(info->probe_type, "map_rom")) {
553 				dev_warn(&dev->dev,
554 					 "map_probe() failed for type %s\n",
555 					 info->probe_type);
556 
557 				info->mtds[i] = do_map_probe("map_rom",
558 							     &info->maps[i]);
559 			}
560 		} else {
561 			int j;
562 
563 			for (j = 0; j < ARRAY_SIZE(rom_probe_types); j++) {
564 				info->mtds[i] = do_map_probe(rom_probe_types[j],
565 							     &info->maps[i]);
566 				if (info->mtds[i])
567 					break;
568 			}
569 		}
570 
571 		if (!info->mtds[i]) {
572 			dev_err(&dev->dev, "map_probe failed\n");
573 			err = -ENXIO;
574 			goto err_out;
575 		}
576 		info->mtds[i]->dev.parent = &dev->dev;
577 	}
578 
579 	if (info->nmaps == 1) {
580 		info->cmtd = info->mtds[0];
581 	} else {
582 		/*
583 		 * We detected multiple devices. Concatenate them together.
584 		 */
585 		info->cmtd = mtd_concat_create(info->mtds, info->nmaps,
586 					       dev_name(&dev->dev));
587 		if (!info->cmtd)
588 			err = -ENXIO;
589 	}
590 	if (err)
591 		goto err_out;
592 
593 	spin_lock_init(&info->vpp_lock);
594 
595 	mtd_set_of_node(info->cmtd, dev->dev.of_node);
596 	err = mtd_device_parse_register(info->cmtd, info->part_types, NULL,
597 					info->parts, info->nparts);
598 	if (err)
599 		goto err_out;
600 
601 	return 0;
602 
603 err_out:
604 	physmap_flash_remove(dev);
605 	return err;
606 }
607 
608 #ifdef CONFIG_PM
609 static void physmap_flash_shutdown(struct platform_device *dev)
610 {
611 	struct physmap_flash_info *info = platform_get_drvdata(dev);
612 	int i;
613 
614 	for (i = 0; i < info->nmaps && info->mtds[i]; i++)
615 		if (mtd_suspend(info->mtds[i]) == 0)
616 			mtd_resume(info->mtds[i]);
617 }
618 #else
619 #define physmap_flash_shutdown NULL
620 #endif
621 
622 static struct platform_driver physmap_flash_driver = {
623 	.probe		= physmap_flash_probe,
624 	.remove_new	= physmap_flash_remove,
625 	.shutdown	= physmap_flash_shutdown,
626 	.driver		= {
627 		.name	= "physmap-flash",
628 		.of_match_table = of_flash_match,
629 	},
630 };
631 
632 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
633 static struct physmap_flash_data physmap_flash_data = {
634 	.width		= CONFIG_MTD_PHYSMAP_BANKWIDTH,
635 };
636 
637 static struct resource physmap_flash_resource = {
638 	.start		= CONFIG_MTD_PHYSMAP_START,
639 	.end		= CONFIG_MTD_PHYSMAP_START + CONFIG_MTD_PHYSMAP_LEN - 1,
640 	.flags		= IORESOURCE_MEM,
641 };
642 
643 static struct platform_device physmap_flash = {
644 	.name		= "physmap-flash",
645 	.id		= 0,
646 	.dev		= {
647 		.platform_data	= &physmap_flash_data,
648 	},
649 	.num_resources	= 1,
650 	.resource	= &physmap_flash_resource,
651 };
652 #endif
653 
654 static int __init physmap_init(void)
655 {
656 	int err;
657 
658 	err = platform_driver_register(&physmap_flash_driver);
659 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
660 	if (err == 0) {
661 		err = platform_device_register(&physmap_flash);
662 		if (err)
663 			platform_driver_unregister(&physmap_flash_driver);
664 	}
665 #endif
666 
667 	return err;
668 }
669 
670 static void __exit physmap_exit(void)
671 {
672 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
673 	platform_device_unregister(&physmap_flash);
674 #endif
675 	platform_driver_unregister(&physmap_flash_driver);
676 }
677 
678 module_init(physmap_init);
679 module_exit(physmap_exit);
680 
681 MODULE_LICENSE("GPL");
682 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
683 MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
684 MODULE_AUTHOR("Mike Frysinger <vapier@gentoo.org>");
685 MODULE_DESCRIPTION("Generic configurable MTD map driver");
686 
687 /* legacy platform drivers can't hotplug or coldplg */
688 #ifndef CONFIG_MTD_PHYSMAP_COMPAT
689 /* work with hotplug and coldplug */
690 MODULE_ALIAS("platform:physmap-flash");
691 #endif
692