[mirror_ubuntu-artful-kernel.git] / drivers / mtd / bcm63xxpart.c

/*
 * BCM63XX CFE image tag parser
 *
 * Copyright © 2006-2008  Florian Fainelli <florian@openwrt.org>
 *			  Mike Albon <malbon@openwrt.org>
 * Copyright © 2009-2010  Daniel Dickinson <openwrt@cshore.neomailbox.net>
 * Copyright © 2011-2013  Jonas Gorski <jonas.gorski@gmail.com>
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/bcm963xx_nvram.h>
#include <linux/bcm963xx_tag.h>
#include <linux/crc32.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>

#define BCM963XX_CFE_BLOCK_SIZE		SZ_64K	/* always at least 64KiB */

#define BCM963XX_CFE_MAGIC_OFFSET	0x4e0
#define BCM963XX_CFE_VERSION_OFFSET	0x570
#define BCM963XX_NVRAM_OFFSET		0x580

/* Ensure strings read from flash structs are null terminated */
#define STR_NULL_TERMINATE(x) \
	do { char *_str = (x); _str[sizeof(x) - 1] = 0; } while (0)

static int bcm63xx_detect_cfe(struct mtd_info *master)
{
	char buf[9];
	int ret;
	size_t retlen;

	ret = mtd_read(master, BCM963XX_CFE_VERSION_OFFSET, 5, &retlen,
		       (void *)buf);
	buf[retlen] = 0;

	if (ret)
		return ret;

	if (strncmp("cfe-v", buf, 5) == 0)
		return 0;

	/* very old CFE's do not have the cfe-v string, so check for magic */
	ret = mtd_read(master, BCM963XX_CFE_MAGIC_OFFSET, 8, &retlen,
		       (void *)buf);
	buf[retlen] = 0;

	return strncmp("CFE1CFE1", buf, 8);
}

static int bcm63xx_read_nvram(struct mtd_info *master,
	struct bcm963xx_nvram *nvram)
{
	u32 actual_crc, expected_crc;
	size_t retlen;
	int ret;

	/* extract nvram data */
	ret = mtd_read(master, BCM963XX_NVRAM_OFFSET, BCM963XX_NVRAM_V5_SIZE,
			&retlen, (void *)nvram);
	if (ret)
		return ret;

	ret = bcm963xx_nvram_checksum(nvram, &expected_crc, &actual_crc);
	if (ret)
		pr_warn("nvram checksum failed, contents may be invalid (expected %08x, got %08x)\n",
			expected_crc, actual_crc);

	if (!nvram->psi_size)
		nvram->psi_size = BCM963XX_DEFAULT_PSI_SIZE;

	return 0;
}

static int bcm63xx_read_image_tag(struct mtd_info *master, const char *name,
	loff_t tag_offset, struct bcm_tag *buf)
{
	int ret;
	size_t retlen;
	u32 computed_crc;

	ret = mtd_read(master, tag_offset, sizeof(*buf), &retlen, (void *)buf);
	if (ret)
		return ret;

	if (retlen != sizeof(*buf))
		return -EIO;

	computed_crc = crc32_le(IMAGETAG_CRC_START, (u8 *)buf,
				offsetof(struct bcm_tag, header_crc));
	if (computed_crc == buf->header_crc) {
		STR_NULL_TERMINATE(buf->board_id);
		STR_NULL_TERMINATE(buf->tag_version);

		pr_info("%s: CFE image tag found at 0x%llx with version %s, board type %s\n",
			name, tag_offset, buf->tag_version, buf->board_id);

		return 0;
	}

	pr_warn("%s: CFE image tag at 0x%llx CRC invalid (expected %08x, actual %08x)\n",
		name, tag_offset, buf->header_crc, computed_crc);
	return 1;
}

static int bcm63xx_parse_cfe_partitions(struct mtd_info *master,
					const struct mtd_partition **pparts,
					struct mtd_part_parser_data *data)
{
	/* CFE, NVRAM and global Linux are always present */
	int nrparts = 3, curpart = 0;
	struct bcm963xx_nvram *nvram = NULL;
	struct bcm_tag *buf = NULL;
	struct mtd_partition *parts;
	int ret;
	unsigned int rootfsaddr, kerneladdr, spareaddr;
	unsigned int rootfslen, kernellen, sparelen, totallen;
	unsigned int cfelen, nvramlen;
	unsigned int cfe_erasesize;
	int i;
	bool rootfs_first = false;

	if (bcm63xx_detect_cfe(master))
		return -EINVAL;

	nvram = vzalloc(sizeof(*nvram));
	if (!nvram)
		return -ENOMEM;

	ret = bcm63xx_read_nvram(master, nvram);
	if (ret)
		goto out;

	cfe_erasesize = max_t(uint32_t, master->erasesize,
			      BCM963XX_CFE_BLOCK_SIZE);

	cfelen = cfe_erasesize;
	nvramlen = nvram->psi_size * SZ_1K;
	nvramlen = roundup(nvramlen, cfe_erasesize);

	/* Allocate memory for buffer */
	buf = vmalloc(sizeof(struct bcm_tag));
	if (!buf) {
		ret = -ENOMEM;
		goto out;
	}

	/* Get the tag */
	ret = bcm63xx_read_image_tag(master, "rootfs", cfelen, buf);
	if (!ret) {
		sscanf(buf->flash_image_start, "%u", &rootfsaddr);
		sscanf(buf->kernel_address, "%u", &kerneladdr);
		sscanf(buf->kernel_length, "%u", &kernellen);
		sscanf(buf->total_length, "%u", &totallen);

		kerneladdr = kerneladdr - BCM963XX_EXTENDED_SIZE;
		rootfsaddr = rootfsaddr - BCM963XX_EXTENDED_SIZE;
		spareaddr = roundup(totallen, master->erasesize) + cfelen;

		if (rootfsaddr < kerneladdr) {
			/* default Broadcom layout */
			rootfslen = kerneladdr - rootfsaddr;
			rootfs_first = true;
		} else {
			/* OpenWrt layout */
			rootfsaddr = kerneladdr + kernellen;
			rootfslen = spareaddr - rootfsaddr;
		}
	} else if (ret > 0) {
		kernellen = 0;
		rootfslen = 0;
		rootfsaddr = 0;
		spareaddr = cfelen;
	} else {
		goto out;
	}
	sparelen = master->size - spareaddr - nvramlen;

	/* Determine number of partitions */
	if (rootfslen > 0)
		nrparts++;

	if (kernellen > 0)
		nrparts++;

	/* Ask kernel for more memory */
	parts = kzalloc(sizeof(*parts) * nrparts + 10 * nrparts, GFP_KERNEL);
	if (!parts) {
		ret = -ENOMEM;
		goto out;
	}

	/* Start building partition list */
	parts[curpart].name = "CFE";
	parts[curpart].offset = 0;
	parts[curpart].size = cfelen;
	curpart++;

	if (kernellen > 0) {
		int kernelpart = curpart;

		if (rootfslen > 0 && rootfs_first)
			kernelpart++;
		parts[kernelpart].name = "kernel";
		parts[kernelpart].offset = kerneladdr;
		parts[kernelpart].size = kernellen;
		curpart++;
	}

	if (rootfslen > 0) {
		int rootfspart = curpart;

		if (kernellen > 0 && rootfs_first)
			rootfspart--;
		parts[rootfspart].name = "rootfs";
		parts[rootfspart].offset = rootfsaddr;
		parts[rootfspart].size = rootfslen;
		if (sparelen > 0  && !rootfs_first)
			parts[rootfspart].size += sparelen;
		curpart++;
	}

	parts[curpart].name = "nvram";
	parts[curpart].offset = master->size - nvramlen;
	parts[curpart].size = nvramlen;
	curpart++;

	/* Global partition "linux" to make easy firmware upgrade */
	parts[curpart].name = "linux";
	parts[curpart].offset = cfelen;
	parts[curpart].size = master->size - cfelen - nvramlen;

	for (i = 0; i < nrparts; i++)
		pr_info("Partition %d is %s offset %llx and length %llx\n", i,
			parts[i].name, parts[i].offset,	parts[i].size);

	pr_info("Spare partition is offset %x and length %x\n",	spareaddr,
		sparelen);

	*pparts = parts;
	ret = 0;

out:
	vfree(nvram);
	vfree(buf);

	if (ret)
		return ret;

	return nrparts;
};

static struct mtd_part_parser bcm63xx_cfe_parser = {
	.parse_fn = bcm63xx_parse_cfe_partitions,
	.name = "bcm63xxpart",
};
module_mtd_part_parser(bcm63xx_cfe_parser);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");
MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com");
MODULE_DESCRIPTION("MTD partitioning for BCM63XX CFE bootloaders");
Commit	Line	Data
70a3c167 JG	1	/*
	2	* BCM63XX CFE image tag parser
	3	*
	4	* Copyright © 2006-2008 Florian Fainelli <florian@openwrt.org>
	5	* Mike Albon <malbon@openwrt.org>
	6	* Copyright © 2009-2010 Daniel Dickinson <openwrt@cshore.neomailbox.net>
d085eea1	7	* Copyright © 2011-2013 Jonas Gorski <jonas.gorski@gmail.com>
70a3c167 JG	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or
	12	* (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to the Free Software
	21	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	22	*
	23	*/
	24
	25	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	26
436e94a6	27	#include <linux/bcm963xx_nvram.h>
8fce60b8	28	#include <linux/bcm963xx_tag.h>
f98872fc	29	#include <linux/crc32.h>
70a3c167 JG	30	#include <linux/module.h>
70a3c167 JG	31	#include <linux/kernel.h>
c88fd9d9	32	#include <linux/sizes.h>
70a3c167 JG	33	#include <linux/slab.h>
	34	#include <linux/vmalloc.h>
	35	#include <linux/mtd/mtd.h>
	36	#include <linux/mtd/partitions.h>
	37
436e94a6	38	#define BCM963XX_CFE_BLOCK_SIZE SZ_64K /* always at least 64KiB */
70a3c167	39
436e94a6 SA	40	#define BCM963XX_CFE_MAGIC_OFFSET 0x4e0
	41	#define BCM963XX_CFE_VERSION_OFFSET 0x570
	42	#define BCM963XX_NVRAM_OFFSET 0x580
f2d9739b	43
7fffa694 SA	44	/* Ensure strings read from flash structs are null terminated */
	45	#define STR_NULL_TERMINATE(x) \
	46	do { char *_str = (x); _str[sizeof(x) - 1] = 0; } while (0)
	47
70a3c167 JG	48	static int bcm63xx_detect_cfe(struct mtd_info *master)
70a3c167 JG	49	{
70a3c167 JG	50	char buf[9];
	51	int ret;
	52	size_t retlen;
	53
329ad399 AB	54	ret = mtd_read(master, BCM963XX_CFE_VERSION_OFFSET, 5, &retlen,
329ad399 AB	55	(void *)buf);
f2d9739b JG	56	buf[retlen] = 0;
	57
	58	if (ret)
	59	return ret;
	60
	61	if (strncmp("cfe-v", buf, 5) == 0)
	62	return 0;
	63
	64	/* very old CFE's do not have the cfe-v string, so check for magic */
436e94a6	65	ret = mtd_read(master, BCM963XX_CFE_MAGIC_OFFSET, 8, &retlen,
329ad399	66	(void *)buf);
70a3c167	67	buf[retlen] = 0;
70a3c167	68
f2d9739b	69	return strncmp("CFE1CFE1", buf, 8);
70a3c167 JG	70	}
70a3c167 JG	71
436e94a6 SA	72	static int bcm63xx_read_nvram(struct mtd_info *master,
	73	struct bcm963xx_nvram *nvram)
	74	{
	75	u32 actual_crc, expected_crc;
	76	size_t retlen;
	77	int ret;
	78
	79	/* extract nvram data */
	80	ret = mtd_read(master, BCM963XX_NVRAM_OFFSET, BCM963XX_NVRAM_V5_SIZE,
	81	&retlen, (void *)nvram);
	82	if (ret)
	83	return ret;
	84
	85	ret = bcm963xx_nvram_checksum(nvram, &expected_crc, &actual_crc);
	86	if (ret)
	87	pr_warn("nvram checksum failed, contents may be invalid (expected %08x, got %08x)\n",
	88	expected_crc, actual_crc);
	89
	90	if (!nvram->psi_size)
	91	nvram->psi_size = BCM963XX_DEFAULT_PSI_SIZE;
	92
	93	return 0;
	94	}
	95
7fffa694 SA	96	static int bcm63xx_read_image_tag(struct mtd_info master, const char name,
	97	loff_t tag_offset, struct bcm_tag *buf)
	98	{
	99	int ret;
	100	size_t retlen;
	101	u32 computed_crc;
	102
	103	ret = mtd_read(master, tag_offset, sizeof(buf), &retlen, (void )buf);
	104	if (ret)
	105	return ret;
	106
	107	if (retlen != sizeof(*buf))
	108	return -EIO;
	109
	110	computed_crc = crc32_le(IMAGETAG_CRC_START, (u8 *)buf,
	111	offsetof(struct bcm_tag, header_crc));
	112	if (computed_crc == buf->header_crc) {
	113	STR_NULL_TERMINATE(buf->board_id);
	114	STR_NULL_TERMINATE(buf->tag_version);
	115
	116	pr_info("%s: CFE image tag found at 0x%llx with version %s, board type %s\n",
	117	name, tag_offset, buf->tag_version, buf->board_id);
	118
	119	return 0;
	120	}
	121
	122	pr_warn("%s: CFE image tag at 0x%llx CRC invalid (expected %08x, actual %08x)\n",
	123	name, tag_offset, buf->header_crc, computed_crc);
	124	return 1;
	125	}
	126
70a3c167	127	static int bcm63xx_parse_cfe_partitions(struct mtd_info *master,
b9adf469	128	const struct mtd_partition **pparts,
70a3c167 JG	129	struct mtd_part_parser_data *data)
	130	{
	131	/* CFE, NVRAM and global Linux are always present */
	132	int nrparts = 3, curpart = 0;
436e94a6 SA	133	struct bcm963xx_nvram *nvram = NULL;
436e94a6 SA	134	struct bcm_tag *buf = NULL;
70a3c167 JG	135	struct mtd_partition *parts;
70a3c167 JG	136	int ret;
70a3c167 JG	137	unsigned int rootfsaddr, kerneladdr, spareaddr;
70a3c167 JG	138	unsigned int rootfslen, kernellen, sparelen, totallen;
678eb9bb	139	unsigned int cfelen, nvramlen;
4e4fb639	140	unsigned int cfe_erasesize;
70a3c167	141	int i;
5329d67c	142	bool rootfs_first = false;
70a3c167 JG	143
	144	if (bcm63xx_detect_cfe(master))
	145	return -EINVAL;
	146
436e94a6 SA	147	nvram = vzalloc(sizeof(*nvram));
	148	if (!nvram)
	149	return -ENOMEM;
	150
	151	ret = bcm63xx_read_nvram(master, nvram);
	152	if (ret)
	153	goto out;
	154
4e4fb639	155	cfe_erasesize = max_t(uint32_t, master->erasesize,
436e94a6	156	BCM963XX_CFE_BLOCK_SIZE);
4e4fb639 JG	157
4e4fb639 JG	158	cfelen = cfe_erasesize;
436e94a6	159	nvramlen = nvram->psi_size * SZ_1K;
d085eea1	160	nvramlen = roundup(nvramlen, cfe_erasesize);
678eb9bb	161
70a3c167 JG	162	/* Allocate memory for buffer */
70a3c167 JG	163	buf = vmalloc(sizeof(struct bcm_tag));
436e94a6 SA	164	if (!buf) {
	165	ret = -ENOMEM;
	166	goto out;
	167	}
70a3c167 JG	168
70a3c167 JG	169	/* Get the tag */
7fffa694 SA	170	ret = bcm63xx_read_image_tag(master, "rootfs", cfelen, buf);
7fffa694 SA	171	if (!ret) {
5329d67c	172	sscanf(buf->flash_image_start, "%u", &rootfsaddr);
f98872fc JG	173	sscanf(buf->kernel_address, "%u", &kerneladdr);
	174	sscanf(buf->kernel_length, "%u", &kernellen);
	175	sscanf(buf->total_length, "%u", &totallen);
	176
1f29cb19 SA	177	kerneladdr = kerneladdr - BCM963XX_EXTENDED_SIZE;
1f29cb19 SA	178	rootfsaddr = rootfsaddr - BCM963XX_EXTENDED_SIZE;
f98872fc	179	spareaddr = roundup(totallen, master->erasesize) + cfelen;
5329d67c JG	180
	181	if (rootfsaddr < kerneladdr) {
	182	/* default Broadcom layout */
	183	rootfslen = kerneladdr - rootfsaddr;
	184	rootfs_first = true;
	185	} else {
	186	/* OpenWrt layout */
	187	rootfsaddr = kerneladdr + kernellen;
	188	rootfslen = spareaddr - rootfsaddr;
	189	}
7fffa694	190	} else if (ret > 0) {
f98872fc JG	191	kernellen = 0;
	192	rootfslen = 0;
	193	rootfsaddr = 0;
	194	spareaddr = cfelen;
7fffa694 SA	195	} else {
7fffa694 SA	196	goto out;
f98872fc	197	}
e190401b	198	sparelen = master->size - spareaddr - nvramlen;
70a3c167 JG	199
70a3c167 JG	200	/* Determine number of partitions */
fafc3d68	201	if (rootfslen > 0)
70a3c167	202	nrparts++;
fafc3d68 JG	203
fafc3d68 JG	204	if (kernellen > 0)
70a3c167	205	nrparts++;
70a3c167 JG	206
	207	/* Ask kernel for more memory */
	208	parts = kzalloc(sizeof(parts) nrparts + 10 * nrparts, GFP_KERNEL);
	209	if (!parts) {
436e94a6 SA	210	ret = -ENOMEM;
436e94a6 SA	211	goto out;
70a3c167 JG	212	}
	213
	214	/* Start building partition list */
	215	parts[curpart].name = "CFE";
	216	parts[curpart].offset = 0;
678eb9bb	217	parts[curpart].size = cfelen;
70a3c167 JG	218	curpart++;
	219
	220	if (kernellen > 0) {
5329d67c JG	221	int kernelpart = curpart;
	222
	223	if (rootfslen > 0 && rootfs_first)
	224	kernelpart++;
	225	parts[kernelpart].name = "kernel";
	226	parts[kernelpart].offset = kerneladdr;
	227	parts[kernelpart].size = kernellen;
70a3c167 JG	228	curpart++;
	229	}
	230
	231	if (rootfslen > 0) {
5329d67c JG	232	int rootfspart = curpart;
	233
	234	if (kernellen > 0 && rootfs_first)
	235	rootfspart--;
	236	parts[rootfspart].name = "rootfs";
	237	parts[rootfspart].offset = rootfsaddr;
	238	parts[rootfspart].size = rootfslen;
	239	if (sparelen > 0 && !rootfs_first)
	240	parts[rootfspart].size += sparelen;
70a3c167 JG	241	curpart++;
	242	}
	243
	244	parts[curpart].name = "nvram";
678eb9bb JG	245	parts[curpart].offset = master->size - nvramlen;
678eb9bb JG	246	parts[curpart].size = nvramlen;
f3f9a5da	247	curpart++;
70a3c167 JG	248
70a3c167 JG	249	/* Global partition "linux" to make easy firmware upgrade */
70a3c167	250	parts[curpart].name = "linux";
327c62c5 JG	251	parts[curpart].offset = cfelen;
327c62c5 JG	252	parts[curpart].size = master->size - cfelen - nvramlen;
70a3c167 JG	253
70a3c167 JG	254	for (i = 0; i < nrparts; i++)
60768368 JG	255	pr_info("Partition %d is %s offset %llx and length %llx\n", i,
60768368 JG	256	parts[i].name, parts[i].offset, parts[i].size);
70a3c167 JG	257
	258	pr_info("Spare partition is offset %x and length %x\n", spareaddr,
	259	sparelen);
	260
	261	*pparts = parts;
436e94a6 SA	262	ret = 0;
	263
	264	out:
	265	vfree(nvram);
70a3c167 JG	266	vfree(buf);
70a3c167 JG	267
436e94a6 SA	268	if (ret)
	269	return ret;
	270
70a3c167 JG	271	return nrparts;
	272	};
	273
	274	static struct mtd_part_parser bcm63xx_cfe_parser = {
70a3c167 JG	275	.parse_fn = bcm63xx_parse_cfe_partitions,
	276	.name = "bcm63xxpart",
	277	};
b8f70bad	278	module_mtd_part_parser(bcm63xx_cfe_parser);
70a3c167 JG	279
	280	MODULE_LICENSE("GPL");
	281	MODULE_AUTHOR("Daniel Dickinson <openwrt@cshore.neomailbox.net>");
	282	MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
	283	MODULE_AUTHOR("Mike Albon <malbon@openwrt.org>");
	284	MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com");
	285	MODULE_DESCRIPTION("MTD partitioning for BCM63XX CFE bootloaders");