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
50struct 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
66static 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
94static 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)
121static 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
142static 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
159static 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
181static 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
196static 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
218static 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
229static 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)
236static 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};
268MODULE_DEVICE_TABLE(of, of_flash_match);
269
270static const char * const of_default_part_probes[] = {
271	"cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL
272};
273
274static 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
296static 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
328static 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
401static int physmap_flash_of_init(struct platform_device *dev)
402{
403	return -ENOTSUPP;
404}
405#endif /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
406
407static const char * const rom_probe_types[] = {
408	"cfi_probe", "jedec_probe", "qinfo_probe", "map_rom",
409};
410
411static const char * const part_probe_types[] = {
412	"cmdlinepart", "RedBoot", "afs", NULL
413};
414
415static 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
446static 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
603err_out:
604	physmap_flash_remove(dev);
605	return err;
606}
607
608#ifdef CONFIG_PM
609static 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
622static 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
633static struct physmap_flash_data physmap_flash_data = {
634	.width		= CONFIG_MTD_PHYSMAP_BANKWIDTH,
635};
636
637static 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
643static 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
654static 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
670static 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
678module_init(physmap_init);
679module_exit(physmap_exit);
680
681MODULE_LICENSE("GPL");
682MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
683MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
684MODULE_AUTHOR("Mike Frysinger <vapier@gentoo.org>");
685MODULE_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 */
690MODULE_ALIAS("platform:physmap-flash");
691#endif
692