linux-imx

/*

 * BCM47XX MTD partitioning

 *

 * Copyright © 2012 Rafał Miłecki <zajec5@gmail.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 */

​

#include <linux/bcm47xx_nvram.h>

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/slab.h>

#include <linux/mtd/mtd.h>

#include <linux/mtd/partitions.h>

​

#include <uapi/linux/magic.h>

​

/*

 * NAND flash on Netgear R6250 was verified to contain 15 partitions.

 * This will result in allocating too big array for some old devices, but the

 * memory will be freed soon anyway (see mtd_device_parse_register).

 */

#define BCM47XXPART_MAX_PARTS       20

​

/*

 * Amount of bytes we read when analyzing each block of flash memory.

 * Set it big enough to allow detecting partition and reading important data.

 */

#define BCM47XXPART_BYTES_TO_READ   0x4e8

​

/* Magics */

#define BOARD_DATA_MAGIC        0x5246504D  /* MPFR */

#define BOARD_DATA_MAGIC2       0xBD0D0BBD

#define CFE_MAGIC           0x43464531  /* 1EFC */

#define FACTORY_MAGIC           0x59544346  /* FCTY */

#define NVRAM_HEADER            0x48534C46  /* FLSH */

#define POT_MAGIC1          0x54544f50  /* POTT */

#define POT_MAGIC2          0x504f      /* OP */

#define ML_MAGIC1           0x39685a42

#define ML_MAGIC2           0x26594131

#define TRX_MAGIC           0x30524448

#define SHSQ_MAGIC          0x71736873  /* shsq (weird ZTE H218N endianness) */

​

static const char * const trx_types[] = { "trx", NULL };

​

struct trx_header {

    uint32_t magic;

    uint32_t length;

    uint32_t crc32;

    uint16_t flags;

    uint16_t version;

    uint32_t offset[3];

} __packed;

​

static void bcm47xxpart_add_part(struct mtd_partition *part, const char *name,

                 u64 offset, uint32_t mask_flags)

{

    part->name = name;

    part->offset = offset;

    part->mask_flags = mask_flags;

}

​

/**

 * bcm47xxpart_bootpartition - gets index of TRX partition used by bootloader

 *

 * Some devices may have more than one TRX partition. In such case one of them

 * is the main one and another a failsafe one. Bootloader may fallback to the

 * failsafe firmware if it detects corruption of the main image.

 *

 * This function provides info about currently used TRX partition. It's the one

 * containing kernel started by the bootloader.

 */

static int bcm47xxpart_bootpartition(void)

{

    char buf[4];

    int bootpartition;

​

    /* Check CFE environment variable */

    if (bcm47xx_nvram_getenv("bootpartition", buf, sizeof(buf)) > 0) {

        if (!kstrtoint(buf, 0, &bootpartition))

            return bootpartition;

    }

​

    return 0;

}

​

static int bcm47xxpart_parse(struct mtd_info *master,

                 const struct mtd_partition **pparts,

                 struct mtd_part_parser_data *data)