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Release 4.14 drivers/mtd/bcm47xxpart.c

Directory: drivers/mtd
/*
 * 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; }

Contributors

PersonTokensPropCommitsCommitProp
Rafał Miłecki40100.00%2100.00%
Total40100.00%2100.00%

/** * 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; }

Contributors

PersonTokensPropCommitsCommitProp
Rafał Miłecki55100.00%1100.00%
Total55100.00%1100.00%


static int bcm47xxpart_parse(struct mtd_info *master, const struct mtd_partition **pparts, struct mtd_part_parser_data *data) { struct mtd_partition *parts; uint8_t i, curr_part = 0; uint32_t *buf; size_t bytes_read; uint32_t offset; uint32_t blocksize = master->erasesize; int trx_parts[2]; /* Array with indexes of TRX partitions */ int trx_num = 0; /* Number of found TRX partitions */ int possible_nvram_sizes[] = { 0x8000, 0xF000, 0x10000, }; int err; /* * Some really old flashes (like AT45DB*) had smaller erasesize-s, but * partitions were aligned to at least 0x1000 anyway. */ if (blocksize < 0x1000) blocksize = 0x1000; /* Alloc */ parts = kzalloc(sizeof(struct mtd_partition) * BCM47XXPART_MAX_PARTS, GFP_KERNEL); if (!parts) return -ENOMEM; buf = kzalloc(BCM47XXPART_BYTES_TO_READ, GFP_KERNEL); if (!buf) { kfree(parts); return -ENOMEM; } /* Parse block by block looking for magics */ for (offset = 0; offset <= master->size - blocksize; offset += blocksize) { /* Nothing more in higher memory on BCM47XX (MIPS) */ if (IS_ENABLED(CONFIG_BCM47XX) && offset >= 0x2000000) break; if (curr_part >= BCM47XXPART_MAX_PARTS) { pr_warn("Reached maximum number of partitions, scanning stopped!\n"); break; } /* Read beginning of the block */ err = mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ, &bytes_read, (uint8_t *)buf); if (err && !mtd_is_bitflip(err)) { pr_err("mtd_read error while parsing (offset: 0x%X): %d\n", offset, err); continue; } /* Magic or small NVRAM at 0x400 */ if ((buf[0x4e0 / 4] == CFE_MAGIC && buf[0x4e4 / 4] == CFE_MAGIC) || (buf[0x400 / 4] == NVRAM_HEADER)) { bcm47xxpart_add_part(&parts[curr_part++], "boot", offset, MTD_WRITEABLE); continue; } /* * board_data starts with board_id which differs across boards, * but we can use 'MPFR' (hopefully) magic at 0x100 */ if (buf[0x100 / 4] == BOARD_DATA_MAGIC) { bcm47xxpart_add_part(&parts[curr_part++], "board_data", offset, MTD_WRITEABLE); continue; } /* Found on Huawei E970 */ if (buf[0x000 / 4] == FACTORY_MAGIC) { bcm47xxpart_add_part(&parts[curr_part++], "factory", offset, MTD_WRITEABLE); continue; } /* POT(TOP) */ if (buf[0x000 / 4] == POT_MAGIC1 && (buf[0x004 / 4] & 0xFFFF) == POT_MAGIC2) { bcm47xxpart_add_part(&parts[curr_part++], "POT", offset, MTD_WRITEABLE); continue; } /* ML */ if (buf[0x010 / 4] == ML_MAGIC1 && buf[0x014 / 4] == ML_MAGIC2) { bcm47xxpart_add_part(&parts[curr_part++], "ML", offset, MTD_WRITEABLE); continue; } /* TRX */ if (buf[0x000 / 4] == TRX_MAGIC) { struct trx_header *trx; if (trx_num >= ARRAY_SIZE(trx_parts)) pr_warn("No enough space to store another TRX found at 0x%X\n", offset); else trx_parts[trx_num++] = curr_part; bcm47xxpart_add_part(&parts[curr_part++], "firmware", offset, 0); /* Jump to the end of TRX */ trx = (struct trx_header *)buf; offset = roundup(offset + trx->length, blocksize); /* Next loop iteration will increase the offset */ offset -= blocksize; continue; } /* Squashfs on devices not using TRX */ if (le32_to_cpu(buf[0x000 / 4]) == SQUASHFS_MAGIC || buf[0x000 / 4] == SHSQ_MAGIC) { bcm47xxpart_add_part(&parts[curr_part++], "rootfs", offset, 0); continue; } /* * New (ARM?) devices may have NVRAM in some middle block. Last * block will be checked later, so skip it. */ if (offset != master->size - blocksize && buf[0x000 / 4] == NVRAM_HEADER) { bcm47xxpart_add_part(&parts[curr_part++], "nvram", offset, 0); continue; } /* Read middle of the block */ err = mtd_read(master, offset + 0x8000, 0x4, &bytes_read, (uint8_t *)buf); if (err && !mtd_is_bitflip(err)) { pr_err("mtd_read error while parsing (offset: 0x%X): %d\n", offset, err); continue; } /* Some devices (ex. WNDR3700v3) don't have a standard 'MPFR' */ if (buf[0x000 / 4] == BOARD_DATA_MAGIC2) { bcm47xxpart_add_part(&parts[curr_part++], "board_data", offset, MTD_WRITEABLE); continue; } } /* Look for NVRAM at the end of the last block. */ for (i = 0; i < ARRAY_SIZE(possible_nvram_sizes); i++) { if (curr_part >= BCM47XXPART_MAX_PARTS) { pr_warn("Reached maximum number of partitions, scanning stopped!\n"); break; } offset = master->size - possible_nvram_sizes[i]; err = mtd_read(master, offset, 0x4, &bytes_read, (uint8_t *)buf); if (err && !mtd_is_bitflip(err)) { pr_err("mtd_read error while reading (offset 0x%X): %d\n", offset, err); continue; } /* Standard NVRAM */ if (buf[0] == NVRAM_HEADER) { bcm47xxpart_add_part(&parts[curr_part++], "nvram", master->size - blocksize, 0); break; } } kfree(buf); /* * Assume that partitions end at the beginning of the one they are * followed by. */ for (i = 0; i < curr_part; i++) { u64 next_part_offset = (i < curr_part - 1) ? parts[i + 1].offset : master->size; parts[i].size = next_part_offset - parts[i].offset; } /* If there was TRX parse it now */ for (i = 0; i < trx_num; i++) { struct mtd_partition *trx = &parts[trx_parts[i]]; if (i == bcm47xxpart_bootpartition()) trx->types = trx_types; else trx->name = "failsafe"; } *pparts = parts; return curr_part; }

Contributors

PersonTokensPropCommitsCommitProp
Rafał Miłecki87995.96%1982.61%
Hauke Mehrtens353.82%28.70%
Brian Norris10.11%14.35%
Masahiro Yamada10.11%14.35%
Total916100.00%23100.00%

; static struct mtd_part_parser bcm47xxpart_mtd_parser = { .parse_fn = bcm47xxpart_parse, .name = "bcm47xxpart", }; module_mtd_part_parser(bcm47xxpart_mtd_parser); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("MTD partitioning for BCM47XX flash memories");

Overall Contributors

PersonTokensPropCommitsCommitProp
Rafał Miłecki113196.67%2281.48%
Hauke Mehrtens352.99%27.41%
Brian Norris30.26%27.41%
Masahiro Yamada10.09%13.70%
Total1170100.00%27100.00%
Directory: drivers/mtd
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