[mirror_ubuntu-bionic-kernel.git] / drivers / mtd / maps / physmap_of.c

/*
 * Flash mappings described by the OF (or flattened) device tree
 *
 * Copyright (C) 2006 MontaVista Software Inc.
 * Author: Vitaly Wool <vwool@ru.mvista.com>
 *
 * Revised to handle newer style flash binding by:
 *   Copyright (C) 2007 David Gibson, IBM Corporation.
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <linux/of.h>
#include <linux/of_platform.h>

struct of_flash {
	struct mtd_info		*mtd;
	struct map_info		map;
	struct resource		*res;
#ifdef CONFIG_MTD_PARTITIONS
	struct mtd_partition	*parts;
#endif
};

#ifdef CONFIG_MTD_PARTITIONS
#define OF_FLASH_PARTS(info)	((info)->parts)

static int parse_obsolete_partitions(struct of_device *dev,
				     struct of_flash *info,
				     struct device_node *dp)
{
	int i, plen, nr_parts;
	const struct {
		u32 offset, len;
	} *part;
	const char *names;

	part = of_get_property(dp, "partitions", &plen);
	if (!part)
		return 0; /* No partitions found */

	dev_warn(&dev->dev, "Device tree uses obsolete partition map binding\n");

	nr_parts = plen / sizeof(part[0]);

	info->parts = kzalloc(nr_parts * sizeof(*info->parts), GFP_KERNEL);
	if (!info->parts)
		return -ENOMEM;

	names = of_get_property(dp, "partition-names", &plen);

	for (i = 0; i < nr_parts; i++) {
		info->parts[i].offset = part->offset;
		info->parts[i].size   = part->len & ~1;
		if (part->len & 1) /* bit 0 set signifies read only partition */
			info->parts[i].mask_flags = MTD_WRITEABLE;

		if (names && (plen > 0)) {
			int len = strlen(names) + 1;

			info->parts[i].name = (char *)names;
			plen -= len;
			names += len;
		} else {
			info->parts[i].name = "unnamed";
		}

		part++;
	}

	return nr_parts;
}

static int __devinit parse_partitions(struct of_flash *info,
				      struct of_device *dev)
{
	const char *partname;
	static const char *part_probe_types[]
		= { "cmdlinepart", "RedBoot", NULL };
	struct device_node *dp = dev->node, *pp;
	int nr_parts, i;

	/* First look for RedBoot table or partitions on the command
	 * line, these take precedence over device tree information */
	nr_parts = parse_mtd_partitions(info->mtd, part_probe_types,
					&info->parts, 0);
	if (nr_parts > 0) {
		add_mtd_partitions(info->mtd, info->parts, nr_parts);
		return 0;
	}

	/* First count the subnodes */
	nr_parts = 0;
	for (pp = dp->child; pp; pp = pp->sibling)
		nr_parts++;

	if (nr_parts == 0)
		return parse_obsolete_partitions(dev, info, dp);

	info->parts = kzalloc(nr_parts * sizeof(*info->parts),
			      GFP_KERNEL);
	if (!info->parts)
		return -ENOMEM;

	for (pp = dp->child, i = 0; pp; pp = pp->sibling, i++) {
		const u32 *reg;
		int len;

		reg = of_get_property(pp, "reg", &len);
		if (!reg || (len != 2*sizeof(u32))) {
			dev_err(&dev->dev, "Invalid 'reg' on %s\n",
				dp->full_name);
			kfree(info->parts);
			info->parts = NULL;
			return -EINVAL;
		}
		info->parts[i].offset = reg[0];
		info->parts[i].size = reg[1];

		partname = of_get_property(pp, "label", &len);
		if (!partname)
			partname = of_get_property(pp, "name", &len);
		info->parts[i].name = (char *)partname;

		if (of_get_property(pp, "read-only", &len))
			info->parts[i].mask_flags = MTD_WRITEABLE;
	}

	return nr_parts;
}
#else /* MTD_PARTITIONS */
#define	OF_FLASH_PARTS(info)		(0)
#define parse_partitions(info, dev)	(0)
#endif /* MTD_PARTITIONS */

static int of_flash_remove(struct of_device *dev)
{
	struct of_flash *info;

	info = dev_get_drvdata(&dev->dev);
	if (!info)
		return 0;
	dev_set_drvdata(&dev->dev, NULL);

	if (info->mtd) {
		if (OF_FLASH_PARTS(info)) {
			del_mtd_partitions(info->mtd);
			kfree(OF_FLASH_PARTS(info));
		} else {
			del_mtd_device(info->mtd);
		}
		map_destroy(info->mtd);
	}

	if (info->map.virt)
		iounmap(info->map.virt);

	if (info->res) {
		release_resource(info->res);
		kfree(info->res);
	}

	return 0;
}

/* Helper function to handle probing of the obsolete "direct-mapped"
 * compatible binding, which has an extra "probe-type" property
 * describing the type of flash probe necessary. */
static struct mtd_info * __devinit obsolete_probe(struct of_device *dev,
						  struct map_info *map)
{
	struct device_node *dp = dev->node;
	const char *of_probe;
	struct mtd_info *mtd;
	static const char *rom_probe_types[]
		= { "cfi_probe", "jedec_probe", "map_rom"};
	int i;

	dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" "
		 "flash binding\n");

	of_probe = of_get_property(dp, "probe-type", NULL);
	if (!of_probe) {
		for (i = 0; i < ARRAY_SIZE(rom_probe_types); i++) {
			mtd = do_map_probe(rom_probe_types[i], map);
			if (mtd)
				return mtd;
		}
		return NULL;
	} else if (strcmp(of_probe, "CFI") == 0) {
		return do_map_probe("cfi_probe", map);
	} else if (strcmp(of_probe, "JEDEC") == 0) {
		return do_map_probe("jedec_probe", map);
	} else {
		if (strcmp(of_probe, "ROM") != 0)
			dev_warn(&dev->dev, "obsolete_probe: don't know probe "
				 "type '%s', mapping as rom\n", of_probe);
		return do_map_probe("mtd_rom", map);
	}
}

static int __devinit of_flash_probe(struct of_device *dev,
				    const struct of_device_id *match)
{
	struct device_node *dp = dev->node;
	struct resource res;
	struct of_flash *info;
	const char *probe_type = match->data;
	const u32 *width;
	int err;

	err = -ENXIO;
	if (of_address_to_resource(dp, 0, &res)) {
		dev_err(&dev->dev, "Can't get IO address from device tree\n");
		goto err_out;
	}

       	dev_dbg(&dev->dev, "of_flash device: %.8llx-%.8llx\n",
		(unsigned long long)res.start, (unsigned long long)res.end);

	err = -ENOMEM;
	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (!info)
		goto err_out;

	dev_set_drvdata(&dev->dev, info);

	err = -EBUSY;
	info->res = request_mem_region(res.start, res.end - res.start + 1,
				       dev->dev.bus_id);
	if (!info->res)
		goto err_out;

	err = -ENXIO;
	width = of_get_property(dp, "bank-width", NULL);
	if (!width) {
		dev_err(&dev->dev, "Can't get bank width from device tree\n");
		goto err_out;
	}

	info->map.name = dev->dev.bus_id;
	info->map.phys = res.start;
	info->map.size = res.end - res.start + 1;
	info->map.bankwidth = *width;

	err = -ENOMEM;
	info->map.virt = ioremap(info->map.phys, info->map.size);
	if (!info->map.virt) {
		dev_err(&dev->dev, "Failed to ioremap() flash region\n");
		goto err_out;
	}

	simple_map_init(&info->map);

	if (probe_type)
		info->mtd = do_map_probe(probe_type, &info->map);
	else
		info->mtd = obsolete_probe(dev, &info->map);

	err = -ENXIO;
	if (!info->mtd) {
		dev_err(&dev->dev, "do_map_probe() failed\n");
		goto err_out;
	}
	info->mtd->owner = THIS_MODULE;

	err = parse_partitions(info, dev);
	if (err < 0)
		goto err_out;

	if (err > 0)
		add_mtd_partitions(info->mtd, OF_FLASH_PARTS(info), err);
	else
		add_mtd_device(info->mtd);

	return 0;

err_out:
	of_flash_remove(dev);
	return err;
}

static struct of_device_id of_flash_match[] = {
	{
		.compatible	= "cfi-flash",
		.data		= (void *)"cfi_probe",
	},
	{
		/* FIXME: JEDEC chips can't be safely and reliably
		 * probed, although the mtd code gets it right in
		 * practice most of the time.  We should use the
		 * vendor and device ids specified by the binding to
		 * bypass the heuristic probe code, but the mtd layer
		 * provides, at present, no interface for doing so
		 * :(. */
		.compatible	= "jedec-flash",
		.data		= (void *)"jedec_probe",
	},
	{
		.type		= "rom",
		.compatible	= "direct-mapped"
	},
	{ },
};
MODULE_DEVICE_TABLE(of, of_flash_match);

static struct of_platform_driver of_flash_driver = {
	.name		= "of-flash",
	.match_table	= of_flash_match,
	.probe		= of_flash_probe,
	.remove		= of_flash_remove,
};

static int __init of_flash_init(void)
{
	return of_register_platform_driver(&of_flash_driver);
}

static void __exit of_flash_exit(void)
{
	of_unregister_platform_driver(&of_flash_driver);
}

module_init(of_flash_init);
module_exit(of_flash_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
MODULE_DESCRIPTION("Device tree based MTD map driver");
Commit	Line	Data
a2c2fe4b	1	/*
c4d5e375	2	* Flash mappings described by the OF (or flattened) device tree
a2c2fe4b VW	3	*
	4	* Copyright (C) 2006 MontaVista Software Inc.
	5	* Author: Vitaly Wool <vwool@ru.mvista.com>
	6	*
2099172d DG	7	* Revised to handle newer style flash binding by:
	8	* Copyright (C) 2007 David Gibson, IBM Corporation.
	9	*
a2c2fe4b VW	10	* This program is free software; you can redistribute it and/or modify it
	11	* under the terms of the GNU General Public License as published by the
	12	* Free Software Foundation; either version 2 of the License, or (at your
	13	* option) any later version.
	14	*/
	15
	16	#include <linux/module.h>
	17	#include <linux/types.h>
a2c2fe4b	18	#include <linux/init.h>
a2c2fe4b VW	19	#include <linux/device.h>
	20	#include <linux/mtd/mtd.h>
	21	#include <linux/mtd/map.h>
	22	#include <linux/mtd/partitions.h>
c4d5e375 DG	23	#include <linux/of.h>
c4d5e375 DG	24	#include <linux/of_platform.h>
a2c2fe4b	25
c4d5e375	26	struct of_flash {
a2c2fe4b VW	27	struct mtd_info *mtd;
	28	struct map_info map;
	29	struct resource *res;
	30	#ifdef CONFIG_MTD_PARTITIONS
a2c2fe4b VW	31	struct mtd_partition *parts;
	32	#endif
	33	};
	34
a2c2fe4b	35	#ifdef CONFIG_MTD_PARTITIONS
c4d5e375	36	#define OF_FLASH_PARTS(info) ((info)->parts)
a2c2fe4b	37
2099172d	38	static int parse_obsolete_partitions(struct of_device *dev,
c4d5e375	39	struct of_flash *info,
2099172d	40	struct device_node *dp)
a2c2fe4b	41	{
2099172d DG	42	int i, plen, nr_parts;
	43	const struct {
	44	u32 offset, len;
	45	} *part;
	46	const char *names;
a2c2fe4b	47
2099172d DG	48	part = of_get_property(dp, "partitions", &plen);
2099172d DG	49	if (!part)
c4d5e375	50	return 0; /* No partitions found */
a2c2fe4b	51
2099172d DG	52	dev_warn(&dev->dev, "Device tree uses obsolete partition map binding\n");
	53
	54	nr_parts = plen / sizeof(part[0]);
	55
c4d5e375 DG	56	info->parts = kzalloc(nr_parts * sizeof(*info->parts), GFP_KERNEL);
c4d5e375 DG	57	if (!info->parts)
2099172d	58	return -ENOMEM;
a2c2fe4b	59
2099172d	60	names = of_get_property(dp, "partition-names", &plen);
a2c2fe4b	61
2099172d DG	62	for (i = 0; i < nr_parts; i++) {
	63	info->parts[i].offset = part->offset;
	64	info->parts[i].size = part->len & ~1;
	65	if (part->len & 1) /* bit 0 set signifies read only partition */
	66	info->parts[i].mask_flags = MTD_WRITEABLE;
a2c2fe4b	67
2099172d DG	68	if (names && (plen > 0)) {
2099172d DG	69	int len = strlen(names) + 1;
a2c2fe4b	70
2099172d	71	info->parts[i].name = (char *)names;
a2c2fe4b	72	plen -= len;
2099172d DG	73	names += len;
	74	} else {
	75	info->parts[i].name = "unnamed";
	76	}
	77
	78	part++;
a2c2fe4b	79	}
2099172d DG	80
2099172d DG	81	return nr_parts;
a2c2fe4b	82	}
a2c2fe4b	83
c4d5e375 DG	84	static int __devinit parse_partitions(struct of_flash *info,
c4d5e375 DG	85	struct of_device *dev)
2099172d DG	86	{
	87	const char *partname;
	88	static const char *part_probe_types[]
	89	= { "cmdlinepart", "RedBoot", NULL };
	90	struct device_node dp = dev->node, pp;
	91	int nr_parts, i;
	92
	93	/* First look for RedBoot table or partitions on the command
	94	* line, these take precedence over device tree information */
	95	nr_parts = parse_mtd_partitions(info->mtd, part_probe_types,
	96	&info->parts, 0);
	97	if (nr_parts > 0) {
	98	add_mtd_partitions(info->mtd, info->parts, nr_parts);
	99	return 0;
	100	}
	101
	102	/* First count the subnodes */
	103	nr_parts = 0;
	104	for (pp = dp->child; pp; pp = pp->sibling)
	105	nr_parts++;
	106
c4d5e375 DG	107	if (nr_parts == 0)
	108	return parse_obsolete_partitions(dev, info, dp);
	109
	110	info->parts = kzalloc(nr_parts * sizeof(*info->parts),
	111	GFP_KERNEL);
	112	if (!info->parts)
	113	return -ENOMEM;
2099172d	114
c4d5e375 DG	115	for (pp = dp->child, i = 0; pp; pp = pp->sibling, i++) {
	116	const u32 *reg;
	117	int len;
	118
	119	reg = of_get_property(pp, "reg", &len);
	120	if (!reg \|\| (len != 2*sizeof(u32))) {
	121	dev_err(&dev->dev, "Invalid 'reg' on %s\n",
	122	dp->full_name);
	123	kfree(info->parts);
	124	info->parts = NULL;
	125	return -EINVAL;
2099172d	126	}
c4d5e375 DG	127	info->parts[i].offset = reg[0];
c4d5e375 DG	128	info->parts[i].size = reg[1];
2099172d	129
c4d5e375 DG	130	partname = of_get_property(pp, "label", &len);
	131	if (!partname)
	132	partname = of_get_property(pp, "name", &len);
	133	info->parts[i].name = (char *)partname;
2099172d	134
c4d5e375 DG	135	if (of_get_property(pp, "read-only", &len))
	136	info->parts[i].mask_flags = MTD_WRITEABLE;
	137	}
2099172d	138
c4d5e375	139	return nr_parts;
2099172d DG	140	}
2099172d DG	141	#else /* MTD_PARTITIONS */
c4d5e375 DG	142	#define OF_FLASH_PARTS(info) (0)
c4d5e375 DG	143	#define parse_partitions(info, dev) (0)
2099172d	144	#endif /* MTD_PARTITIONS */
a2c2fe4b	145
c4d5e375	146	static int of_flash_remove(struct of_device *dev)
a2c2fe4b	147	{
c4d5e375	148	struct of_flash *info;
a2c2fe4b VW	149
a2c2fe4b VW	150	info = dev_get_drvdata(&dev->dev);
c4d5e375	151	if (!info)
a2c2fe4b VW	152	return 0;
	153	dev_set_drvdata(&dev->dev, NULL);
	154
c4d5e375 DG	155	if (info->mtd) {
c4d5e375 DG	156	if (OF_FLASH_PARTS(info)) {
a2c2fe4b	157	del_mtd_partitions(info->mtd);
c4d5e375	158	kfree(OF_FLASH_PARTS(info));
a2c2fe4b VW	159	} else {
	160	del_mtd_device(info->mtd);
	161	}
a2c2fe4b VW	162	map_destroy(info->mtd);
	163	}
	164
c4d5e375	165	if (info->map.virt)
a2c2fe4b VW	166	iounmap(info->map.virt);
a2c2fe4b VW	167
c4d5e375	168	if (info->res) {
a2c2fe4b VW	169	release_resource(info->res);
	170	kfree(info->res);
	171	}
	172
	173	return 0;
	174	}
	175
2099172d DG	176	/* Helper function to handle probing of the obsolete "direct-mapped"
	177	* compatible binding, which has an extra "probe-type" property
	178	* describing the type of flash probe necessary. */
	179	static struct mtd_info * __devinit obsolete_probe(struct of_device *dev,
	180	struct map_info *map)
a2c2fe4b VW	181	{
a2c2fe4b VW	182	struct device_node *dp = dev->node;
a2c2fe4b	183	const char *of_probe;
2099172d DG	184	struct mtd_info *mtd;
	185	static const char *rom_probe_types[]
	186	= { "cfi_probe", "jedec_probe", "map_rom"};
	187	int i;
	188
	189	dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" "
	190	"flash binding\n");
	191
	192	of_probe = of_get_property(dp, "probe-type", NULL);
	193	if (!of_probe) {
	194	for (i = 0; i < ARRAY_SIZE(rom_probe_types); i++) {
	195	mtd = do_map_probe(rom_probe_types[i], map);
	196	if (mtd)
	197	return mtd;
	198	}
	199	return NULL;
	200	} else if (strcmp(of_probe, "CFI") == 0) {
	201	return do_map_probe("cfi_probe", map);
	202	} else if (strcmp(of_probe, "JEDEC") == 0) {
	203	return do_map_probe("jedec_probe", map);
	204	} else {
	205	if (strcmp(of_probe, "ROM") != 0)
c4d5e375 DG	206	dev_warn(&dev->dev, "obsolete_probe: don't know probe "
c4d5e375 DG	207	"type '%s', mapping as rom\n", of_probe);
2099172d DG	208	return do_map_probe("mtd_rom", map);
	209	}
	210	}
	211
c4d5e375 DG	212	static int __devinit of_flash_probe(struct of_device *dev,
c4d5e375 DG	213	const struct of_device_id *match)
a2c2fe4b VW	214	{
	215	struct device_node *dp = dev->node;
	216	struct resource res;
c4d5e375 DG	217	struct of_flash *info;
c4d5e375 DG	218	const char *probe_type = match->data;
a2c2fe4b VW	219	const u32 *width;
	220	int err;
	221
c4d5e375	222	err = -ENXIO;
a2c2fe4b	223	if (of_address_to_resource(dp, 0, &res)) {
c4d5e375	224	dev_err(&dev->dev, "Can't get IO address from device tree\n");
a2c2fe4b VW	225	goto err_out;
	226	}
	227
c4d5e375 DG	228	dev_dbg(&dev->dev, "of_flash device: %.8llx-%.8llx\n",
c4d5e375 DG	229	(unsigned long long)res.start, (unsigned long long)res.end);
a2c2fe4b	230
c4d5e375 DG	231	err = -ENOMEM;
	232	info = kzalloc(sizeof(*info), GFP_KERNEL);
	233	if (!info)
a2c2fe4b	234	goto err_out;
a2c2fe4b VW	235
	236	dev_set_drvdata(&dev->dev, info);
	237
c4d5e375	238	err = -EBUSY;
a2c2fe4b	239	info->res = request_mem_region(res.start, res.end - res.start + 1,
c4d5e375 DG	240	dev->dev.bus_id);
c4d5e375 DG	241	if (!info->res)
a2c2fe4b	242	goto err_out;
a2c2fe4b	243
c4d5e375	244	err = -ENXIO;
40cd3a45	245	width = of_get_property(dp, "bank-width", NULL);
c4d5e375 DG	246	if (!width) {
c4d5e375 DG	247	dev_err(&dev->dev, "Can't get bank width from device tree\n");
a2c2fe4b VW	248	goto err_out;
	249	}
	250
	251	info->map.name = dev->dev.bus_id;
	252	info->map.phys = res.start;
	253	info->map.size = res.end - res.start + 1;
	254	info->map.bankwidth = *width;
	255
c4d5e375	256	err = -ENOMEM;
a2c2fe4b	257	info->map.virt = ioremap(info->map.phys, info->map.size);
c4d5e375 DG	258	if (!info->map.virt) {
c4d5e375 DG	259	dev_err(&dev->dev, "Failed to ioremap() flash region\n");
a2c2fe4b VW	260	goto err_out;
	261	}
	262
	263	simple_map_init(&info->map);
	264
2099172d DG	265	if (probe_type)
	266	info->mtd = do_map_probe(probe_type, &info->map);
	267	else
	268	info->mtd = obsolete_probe(dev, &info->map);
	269
c4d5e375 DG	270	err = -ENXIO;
	271	if (!info->mtd) {
	272	dev_err(&dev->dev, "do_map_probe() failed\n");
a2c2fe4b VW	273	goto err_out;
	274	}
	275	info->mtd->owner = THIS_MODULE;
	276
c4d5e375 DG	277	err = parse_partitions(info, dev);
	278	if (err < 0)
	279	goto err_out;
a2c2fe4b	280
c4d5e375 DG	281	if (err > 0)
	282	add_mtd_partitions(info->mtd, OF_FLASH_PARTS(info), err);
	283	else
	284	add_mtd_device(info->mtd);
a2c2fe4b	285
a2c2fe4b VW	286	return 0;
	287
	288	err_out:
c4d5e375	289	of_flash_remove(dev);
a2c2fe4b	290	return err;
a2c2fe4b VW	291	}
a2c2fe4b VW	292
c4d5e375	293	static struct of_device_id of_flash_match[] = {
2099172d DG	294	{
	295	.compatible = "cfi-flash",
	296	.data = (void *)"cfi_probe",
	297	},
	298	{
	299	/* FIXME: JEDEC chips can't be safely and reliably
	300	* probed, although the mtd code gets it right in
	301	* practice most of the time. We should use the
	302	* vendor and device ids specified by the binding to
	303	* bypass the heuristic probe code, but the mtd layer
	304	* provides, at present, no interface for doing so
	305	* :(. */
	306	.compatible = "jedec-flash",
	307	.data = (void *)"jedec_probe",
	308	},
a2c2fe4b VW	309	{
	310	.type = "rom",
	311	.compatible = "direct-mapped"
	312	},
	313	{ },
	314	};
c4d5e375	315	MODULE_DEVICE_TABLE(of, of_flash_match);
a2c2fe4b	316
c4d5e375 DG	317	static struct of_platform_driver of_flash_driver = {
	318	.name = "of-flash",
	319	.match_table = of_flash_match,
	320	.probe = of_flash_probe,
	321	.remove = of_flash_remove,
a2c2fe4b VW	322	};
a2c2fe4b VW	323
c4d5e375	324	static int __init of_flash_init(void)
a2c2fe4b	325	{
c4d5e375	326	return of_register_platform_driver(&of_flash_driver);
a2c2fe4b VW	327	}
a2c2fe4b VW	328
c4d5e375	329	static void __exit of_flash_exit(void)
a2c2fe4b	330	{
c4d5e375	331	of_unregister_platform_driver(&of_flash_driver);
a2c2fe4b VW	332	}
a2c2fe4b VW	333
c4d5e375 DG	334	module_init(of_flash_init);
c4d5e375 DG	335	module_exit(of_flash_exit);
a2c2fe4b VW	336
	337	MODULE_LICENSE("GPL");
	338	MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
c4d5e375	339	MODULE_DESCRIPTION("Device tree based MTD map driver");