mtd: bcm47part driver for BCM47XX chipsets (3cf7f131) · Commits · 戴 / test

drivers/mtd/Kconfig

+7 −0

Original line number	Diff line number	Diff line
		@@ -148,6 +148,13 @@ config MTD_BCM63XX_PARTS
		This provides partions parsing for BCM63xx devices with CFE
		bootloaders.

		config MTD_BCM47XX_PARTS
		tristate "BCM47XX partitioning support"
		depends on BCM47XX
		help
		This provides partitions parser for devices based on BCM47xx
		boards.

		comment "User Modules And Translation Layers"

		config MTD_CHAR

drivers/mtd/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -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_BCM47XX_PARTS) += bcm47xxpart.o

		# 'Users' - code which presents functionality to userspace.
		obj-$(CONFIG_MTD_CHAR) += mtdchar.o

drivers/mtd/bcm47xxpart.c

0 → 100644

+202 −0

Original line number	Diff line number	Diff line
		/*
		* 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/module.h>
		#include <linux/kernel.h>
		#include <linux/slab.h>
		#include <linux/mtd/mtd.h>
		#include <linux/mtd/partitions.h>
		#include <asm/mach-bcm47xx/nvram.h>

		/* 10 parts were found on sflash on Netgear WNDR4500 */
		#define BCM47XXPART_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 BCM47XXPART_BYTES_TO_READ 0x404

		/* Magics */
		#define BOARD_DATA_MAGIC 0x5246504D /* MPFR */
		#define POT_MAGIC1 0x54544f50 /* POTT */
		#define POT_MAGIC2 0x504f /* OP */
		#define ML_MAGIC1 0x39685a42
		#define ML_MAGIC2 0x26594131
		#define TRX_MAGIC 0x30524448

		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, char name,
		u64 offset, uint32_t mask_flags)
		{
		part->name = name;
		part->offset = offset;
		part->mask_flags = mask_flags;
		}

		static int bcm47xxpart_parse(struct mtd_info *master,
		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 = 0x10000;
		struct trx_header *trx;

		/* Alloc */
		parts = kzalloc(sizeof(struct mtd_partition) * BCM47XXPART_MAX_PARTS,
		GFP_KERNEL);
		buf = kzalloc(BCM47XXPART_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;

		if (curr_part > BCM47XXPART_MAX_PARTS) {
		pr_warn("Reached maximum number of partitions, scanning stopped!\n");
		break;
		}

		/* Read beginning of the block */
		if (mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ,
		&bytes_read, (uint8_t *)buf) < 0) {
		pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
		offset);
		continue;
		}

		/* CFE has small NVRAM at 0x400 */
		if (buf[0x400 / 4] == NVRAM_HEADER) {
		bcm47xxpart_add_part(&parts[curr_part++], "boot",
		offset, MTD_WRITEABLE);
		continue;
		}

		/* Standard NVRAM */
		if (buf[0x000 / 4] == NVRAM_HEADER) {
		bcm47xxpart_add_part(&parts[curr_part++], "nvram",
		offset, 0);
		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;
		}

		/* 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) {
		trx = (struct trx_header *)buf;

		i = 0;
		/* We have LZMA loader if offset[2] points to sth */
		if (trx->offset[2]) {
		bcm47xxpart_add_part(&parts[curr_part++],
		"loader",
		offset + trx->offset[i],
		0);
		i++;
		}

		bcm47xxpart_add_part(&parts[curr_part++], "linux",
		offset + trx->offset[i], 0);
		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.
		*/
		bcm47xxpart_add_part(&parts[curr_part++], "rootfs",
		offset + trx->offset[i], 0);
		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);
		continue;
		}
		}
		kfree(buf);

		/*
		* Assume that partitions end at the beginning of the one they are
		* followed by.
		*/
		for (i = 0; i < curr_part - 1; i++)
		parts[i].size = parts[i + 1].offset - parts[i].offset;
		if (curr_part > 0)
		parts[curr_part - 1].size =
		master->size - parts[curr_part - 1].offset;

		*pparts = parts;
		return curr_part;
		};

		static struct mtd_part_parser bcm47xxpart_mtd_parser = {
		.owner = THIS_MODULE,
		.parse_fn = bcm47xxpart_parse,
		.name = "bcm47xxpart",
		};

		static int __init bcm47xxpart_init(void)
		{
		return register_mtd_parser(&bcm47xxpart_mtd_parser);
		}

		static void __exit bcm47xxpart_exit(void)
		{
		deregister_mtd_parser(&bcm47xxpart_mtd_parser);
		}

		module_init(bcm47xxpart_init);
		module_exit(bcm47xxpart_exit);

		MODULE_LICENSE("GPL");
		MODULE_DESCRIPTION("MTD partitioning for BCM47XX flash memories");

Admin message