diff options
Diffstat (limited to 'target/linux/adm5120/files/drivers/mtd/trxsplit.c')
| -rw-r--r-- | target/linux/adm5120/files/drivers/mtd/trxsplit.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/target/linux/adm5120/files/drivers/mtd/trxsplit.c b/target/linux/adm5120/files/drivers/mtd/trxsplit.c new file mode 100644 index 0000000000..7e4a63b74b --- /dev/null +++ b/target/linux/adm5120/files/drivers/mtd/trxsplit.c @@ -0,0 +1,217 @@ +/* + * Copyright (C) Gabor Juhos <juhosg@openwrt.org> + * + * 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/types.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/kmod.h> +#include <linux/root_dev.h> + +#include <linux/mtd/mtd.h> +#include <linux/mtd/partitions.h> + +#include <linux/byteorder/generic.h> + +#define PFX "trxsplit: " + +#define TRX_MAGIC 0x30524448 /* "HDR0" */ +#define TRX_VERSION 1 +#define TRX_MAX_LEN 0x3A0000 +#define TRX_NO_HEADER 0x1 /* do not write TRX header */ +#define TRX_GZ_FILES 0x2 /* contains individual gzip files */ +#define TRX_MAX_OFFSET 3 +#define TRX_MIN_KERNEL_SIZE 256*1024 + +struct trx_header { + u32 magic; /* "HDR0" */ + u32 len; /* Length of file including header */ + u32 crc32; /* 32-bit CRC from flag_version to end of file */ + u32 flag_version; /* 0:15 flags, 16:31 version */ + u32 offsets[TRX_MAX_OFFSET]; /* Offsets of partitions */ +}; + +#define TRX_ALIGN 0x1000 + +static int trx_nr_parts; +static unsigned long trx_offset; +static struct mtd_info *trx_mtd; +static struct mtd_partition trx_parts[TRX_MAX_OFFSET]; +static struct trx_header trx_hdr; + +static int trxsplit_refresh_partitions(struct mtd_info *mtd); + +static int trxsplit_checktrx(struct mtd_info *mtd, unsigned long offset) +{ + size_t retlen; + int err; + + err = mtd->read(mtd, offset, sizeof(trx_hdr), &retlen, + (void *)&trx_hdr); + if (err) { + printk(KERN_ALERT PFX "unable to read from '%s'\n", mtd->name); + goto err_out; + } + + if (retlen != sizeof(trx_hdr)) { + printk(KERN_ALERT PFX "reading failed on '%s'\n", mtd->name); + goto err_out; + } + + trx_hdr.magic = le32_to_cpu(trx_hdr.magic); + trx_hdr.len = le32_to_cpu(trx_hdr.len); + trx_hdr.crc32 = le32_to_cpu(trx_hdr.crc32); + trx_hdr.flag_version = le32_to_cpu(trx_hdr.flag_version); + trx_hdr.offsets[0] = le32_to_cpu(trx_hdr.offsets[0]); + trx_hdr.offsets[1] = le32_to_cpu(trx_hdr.offsets[1]); + trx_hdr.offsets[2] = le32_to_cpu(trx_hdr.offsets[2]); + + /* sanity checks */ + if (trx_hdr.magic != TRX_MAGIC) + goto err_out; + + if (trx_hdr.len > mtd->size - offset) + goto err_out; + + /* TODO: add crc32 checking too? */ + + return 0; + +err_out: + return -1; +} + +static void trxsplit_findtrx(struct mtd_info *mtd) +{ + unsigned long offset; + int err; + + printk(KERN_INFO PFX "searching TRX header in '%s'\n", mtd->name); + + err = 0; + for (offset = 0; offset < mtd->size; offset += TRX_ALIGN) { + err = trxsplit_checktrx(mtd, offset); + if (err == 0) + break; + } + + if (err) + return; + + printk(KERN_INFO PFX "TRX header found at 0x%lX\n", offset); + + trx_mtd = mtd; + trx_offset = offset; +} + +static void trxsplit_create_partitions(struct mtd_info *mtd) +{ + struct mtd_partition *part = trx_parts; + int err; + int i; + + for (i = 0; i < TRX_MAX_OFFSET; i++) { + part = &trx_parts[i]; + if (trx_hdr.offsets[i] == 0) + continue; + part->offset = trx_offset + trx_hdr.offsets[i]; + trx_nr_parts++; + } + + for (i = 0; i < trx_nr_parts-1; i++) + trx_parts[i].size = trx_parts[i+1].offset - trx_parts[i].offset; + + trx_parts[i].size = mtd->size - trx_parts[i].offset; + + i = 0; + part = &trx_parts[i]; + if (part->size < TRX_MIN_KERNEL_SIZE) { + part->name = "loader"; + i++; + } + + part = &trx_parts[i]; + part->name = "kernel"; + i++; + + part = &trx_parts[i]; + part->name = "rootfs"; + + err = add_mtd_partitions(mtd, trx_parts, trx_nr_parts); + if (err) { + printk(KERN_ALERT PFX "adding TRX partitions failed\n"); + return; + } + + mtd->refresh_device = trxsplit_refresh_partitions; +} + +static int trxsplit_refresh_partitions(struct mtd_info *mtd) +{ + printk(KERN_INFO PFX "refreshing TRX partitions in '%s' (%d,%d)\n", + mtd->name, MTD_BLOCK_MAJOR, mtd->index); + + /* remove old partitions */ + del_mtd_partitions(mtd); + + trxsplit_findtrx(mtd); + if (!trx_mtd) + goto err; + + trxsplit_create_partitions(trx_mtd); + return 1; + +err: + return 0; +} + +static void __init trxsplit_add_mtd(struct mtd_info *mtd) +{ + if (mtd->type != MTD_NORFLASH) { + printk(KERN_INFO PFX "'%s' is not a NOR flash, skipped\n", + mtd->name); + return; + } + + if (!trx_mtd) + trxsplit_findtrx(mtd); +} + +static void __init trxsplit_remove_mtd(struct mtd_info *mtd) +{ + /* nothing to do */ +} + +static struct mtd_notifier trxsplit_notifier __initdata = { + .add = trxsplit_add_mtd, + .remove = trxsplit_remove_mtd, +}; + +static void __init trxsplit_scan(void) +{ + register_mtd_user(&trxsplit_notifier); + unregister_mtd_user(&trxsplit_notifier); +} + +static int __init trxsplit_init(void) +{ + trxsplit_scan(); + + if (trx_mtd) { + printk(KERN_INFO PFX "creating TRX partitions in '%s' " + "(%d,%d)\n", trx_mtd->name, MTD_BLOCK_MAJOR, + trx_mtd->index); + trxsplit_create_partitions(trx_mtd); + } + + return 0; +} + +late_initcall(trxsplit_init); |