From patchwork Sat Aug 25 18:50:52 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [V2] mtd: bcm47part driver for BCM47XX chipsets Date: Sat, 25 Aug 2012 08:50:52 -0000 From: =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= X-Patchwork-Id: 179983 Message-Id: <1345920652-11728-1-git-send-email-zajec5@gmail.com> To: linux-mtd@lists.infradead.org Cc: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= This driver provides parser detecting partitions on BCM47XX flash memories. It has many differences in comparision to older BCM63XX, like: 1) Different CFE with no more trivial MAGICs 2) More partitions types (board_data, ML, POT) 3) Supporting more than 1 flash on a device which resulted in decision of writing new parser. It uses generic mtd interface and was successfully tested with Netgear WNDR4500 router which has 2 flash memories: serial one and NAND one. Signed-off-by: Rafał Miłecki --- V2: 1) Add support for more partitinos (ML and POT) 2) Optimize: don't scan whole flash (like up to 128 MiB) 3) Optimize: don't scan TRX partitions after detecting header --- drivers/mtd/Kconfig | 4 + drivers/mtd/Makefile | 1 + drivers/mtd/bcm47part.c | 193 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 198 insertions(+), 0 deletions(-) create mode 100644 drivers/mtd/bcm47part.c diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig index 27143e0..0cd4096 100644 --- a/drivers/mtd/Kconfig +++ b/drivers/mtd/Kconfig @@ -148,6 +148,10 @@ config MTD_BCM63XX_PARTS This provides partions parsing for BCM63xx devices with CFE bootloaders. +config MTD_BCM47_PARTS + tristate "BCM47XX partitioning support" + depends on BCM47XX + comment "User Modules And Translation Layers" config MTD_CHAR diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile index f901354..dac90e6 100644 --- a/drivers/mtd/Makefile +++ b/drivers/mtd/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_MTD_CMDLINE_PARTS) += cmdlinepart.o obj-$(CONFIG_MTD_AFS_PARTS) += afs.o obj-$(CONFIG_MTD_AR7_PARTS) += ar7part.o obj-$(CONFIG_MTD_BCM63XX_PARTS) += bcm63xxpart.o +obj-$(CONFIG_MTD_BCM47_PARTS) += bcm47part.o # 'Users' - code which presents functionality to userspace. obj-$(CONFIG_MTD_CHAR) += mtdchar.o diff --git a/drivers/mtd/bcm47part.c b/drivers/mtd/bcm47part.c new file mode 100644 index 0000000..29c6828 --- /dev/null +++ b/drivers/mtd/bcm47part.c @@ -0,0 +1,193 @@ +/* + * BCM47XX MTD partitioning + * + * Copyright (C) 2012 Rafał Miłecki + * + * 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 +#include +#include +#include +#include +#include + +/* 10 parts were found on sflash on Netgear WNDR4500 */ +#define BCM47PART_MAX_PARTS 12 + +/* 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 BCM47PART_BYTES_TO_READ 0x401 + +#define TRX_MAGIC 0x30524448 + +struct trx_header { + u32 magic; + u32 length; + u32 crc32; + u16 flags; + u16 version; + u32 offset[3]; +} __packed; + +static int bcm47part_parse(struct mtd_info *master, + struct mtd_partition **pparts, + struct mtd_part_parser_data *data) +{ + struct mtd_partition *parts; + u8 i, curr_part = 0; + u8 *buf; + u32 *fourcc, *fourcc2; + size_t bytes_read; + u32 offset; + u32 blocksize = 0x10000; + struct trx_header *trx; + + /* Alloc */ + parts = kzalloc(sizeof(struct mtd_partition) * BCM47PART_MAX_PARTS, + GFP_KERNEL); + buf = kzalloc(sizeof(*buf) * BCM47PART_BYTES_TO_READ, GFP_KERNEL); + + /* Parse block by block looking for magics */ + for (offset = 0; offset <= master->size - blocksize; + offset += blocksize) { + /* Nothing more in higher memory */ + if (offset >= 0x2000000) + break; + + /* Read beginning of the block */ + if (mtd_read(master, offset, BCM47PART_BYTES_TO_READ, + &bytes_read, buf) < 0) { + pr_err("mtd_read error while parsing (offset: 0x%X)!\n", + offset); + continue; + } + + /* CFE has small NVRAM at 0x400 */ + fourcc = (u32 *)&buf[0x400]; + if (*fourcc == NVRAM_HEADER) { + parts[curr_part].name = "boot"; + parts[curr_part].mask_flags = MTD_WRITEABLE; + parts[curr_part].offset = offset; + curr_part++; + } + + /* Standard NVRAM */ + fourcc = (u32 *)&buf[0x000]; + if (*fourcc == NVRAM_HEADER) { + parts[curr_part].name = "nvram"; + parts[curr_part].mask_flags = MTD_WRITEABLE; + parts[curr_part].offset = offset; + curr_part++; + } + + /* board_data starts with board_id which differs across boards, + * but we can use 'MPFR' (hopefully) magic at 0x100 */ + fourcc = (u32 *)&buf[0x100]; + if (*fourcc == 0x5246504D) { /* MPFR */ + parts[curr_part].name = "board_data"; + parts[curr_part].mask_flags = MTD_WRITEABLE; + parts[curr_part].offset = offset; + curr_part++; + } + + /* POT(TOP) */ + fourcc = (u32 *)&buf[0x000]; + fourcc2 = (u32 *)&buf[0x004]; + if (*fourcc == 0x54544f50 && /* POTT */ + (*fourcc2 & 0xFFFF) == 0x504f) { /* OP */ + parts[curr_part].name = "POT"; + parts[curr_part].mask_flags = MTD_WRITEABLE; + parts[curr_part].offset = offset; + curr_part++; + } + + /* ML */ + fourcc = (u32 *)&buf[0x010]; + fourcc2 = (u32 *)&buf[0x014]; + if (*fourcc == 0x39685a42 && *fourcc2 == 0x26594131) { + parts[curr_part].name = "ML"; + parts[curr_part].mask_flags = MTD_WRITEABLE; + parts[curr_part].offset = offset; + curr_part++; + } + + /* TRX */ + fourcc = (u32 *)&buf[0x000]; + if (*fourcc == TRX_MAGIC) { + trx = (struct trx_header *)buf; + + i = 0; + /* We have LZMA loader if offset[2] points to sth */ + if (trx->offset[2]) { + /* TODO: should we add LZMA loader partition? */ + i++; + } + + parts[curr_part].name = "linux"; + parts[curr_part].mask_flags = MTD_WRITEABLE; + parts[curr_part].offset = offset + trx->offset[i]; + curr_part++; + i++; + + parts[curr_part].name = "rootfs"; + parts[curr_part].mask_flags = MTD_WRITEABLE; + parts[curr_part].offset = offset + trx->offset[i]; + /* Pure rootfs size is known and can be calculated as: + * trx->length - trx->offset[i]. We don't fill it as + * we want to have jffs2 (overlay) in the same mtd. */ + curr_part++; + i++; + + /* We have whole TRX scanned, skip to the next part. Use + * roundown (not roundup), as the loop will increase + * offset in next step. */ + offset = rounddown(offset + trx->length, blocksize); + } + + if (curr_part == BCM47PART_MAX_PARTS) { + pr_warn("Reached maximum number of partitions, scanning stopped!\n"); + break; + } + } + + /* We can't read sizes of some (most of) partitions. Assume that + * these partitions end at the beginning of the one they are + * followed by. */ + for (i = 0; i < curr_part - 1; i++) { + if (parts[i].size == 0) + parts[i].size = parts[i + 1].offset - parts[i].offset; + } + if (curr_part > 0 && parts[curr_part - 1].size == 0) + parts[curr_part - 1].size = + master->size - parts[curr_part - 1].offset; + + *pparts = parts; + return curr_part; +}; + +static struct mtd_part_parser bcm47part_mtd_parser = { + .owner = THIS_MODULE, + .parse_fn = bcm47part_parse, + .name = "bcm47part", +}; + +static int __init bcm47part_init(void) +{ + return register_mtd_parser(&bcm47part_mtd_parser); +} + +static void __exit bcm47part_exit(void) +{ + deregister_mtd_parser(&bcm47part_mtd_parser); +} + +module_init(bcm47part_init); +module_exit(bcm47part_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("MTD partitioning for BCM47XX flash memories");