4 * Copyright (C) 2007 OpenWrt.org
5 * Copyright (C) Gabor Juhos <juhosg at openwrt.org>
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published
9 * by the Free Software Foundation.
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/list.h>
18 #include <linux/kmod.h>
19 #include <linux/root_dev.h>
21 #include <linux/mtd/mtd.h>
22 #include <linux/mtd/partitions.h>
24 #include <linux/byteorder/generic.h>
26 #define PFX "trxsplit: "
28 #define TRX_MAGIC 0x30524448 /* "HDR0" */
30 #define TRX_MAX_LEN 0x3A0000
31 #define TRX_NO_HEADER 0x1 /* do not write TRX header */
32 #define TRX_GZ_FILES 0x2 /* contains individual gzip files */
33 #define TRX_MAX_OFFSET 3
34 #define TRX_MIN_KERNEL_SIZE 256*1024
37 u32 magic; /* "HDR0" */
38 u32 len; /* Length of file including header */
39 u32 crc32; /* 32-bit CRC from flag_version to end of file */
40 u32 flag_version; /* 0:15 flags, 16:31 version */
41 u32 offsets[TRX_MAX_OFFSET]; /* Offsets of partitions */
44 #define TRX_ALIGN 0x1000
46 static int trx_nr_parts;
47 static unsigned long trx_offset;
48 static struct mtd_info *trx_mtd;
49 static struct mtd_partition trx_parts[TRX_MAX_OFFSET];
50 static struct trx_header trx_hdr;
52 static int trxsplit_refresh_partitions(struct mtd_info *mtd);
54 static int trxsplit_checktrx(struct mtd_info *mtd, unsigned long offset)
59 err = mtd->read(mtd, offset, sizeof(trx_hdr), &retlen,
62 printk(KERN_ALERT PFX "unable to read from '%s'\n", mtd->name);
66 if (retlen != sizeof(trx_hdr)) {
67 printk(KERN_ALERT PFX "reading failed on '%s'\n", mtd->name);
71 trx_hdr.magic = le32_to_cpu(trx_hdr.magic);
72 trx_hdr.len = le32_to_cpu(trx_hdr.len);
73 trx_hdr.crc32 = le32_to_cpu(trx_hdr.crc32);
74 trx_hdr.flag_version = le32_to_cpu(trx_hdr.flag_version);
75 trx_hdr.offsets[0] = le32_to_cpu(trx_hdr.offsets[0]);
76 trx_hdr.offsets[1] = le32_to_cpu(trx_hdr.offsets[1]);
77 trx_hdr.offsets[2] = le32_to_cpu(trx_hdr.offsets[2]);
80 if (trx_hdr.magic != TRX_MAGIC)
83 if (trx_hdr.len > mtd->size - offset)
86 /* TODO: add crc32 checking too? */
94 static void trxsplit_findtrx(struct mtd_info *mtd)
99 printk(KERN_INFO PFX "searching TRX header in '%s'\n", mtd->name);
102 for (offset = 0; offset < mtd->size; offset += TRX_ALIGN) {
103 err = trxsplit_checktrx(mtd, offset);
111 printk(KERN_INFO PFX "TRX header found at 0x%lX\n", offset);
117 static void trxsplit_create_partitions(struct mtd_info *mtd)
119 struct mtd_partition *part = trx_parts;
123 for (i = 0; i < TRX_MAX_OFFSET; i++) {
124 part = &trx_parts[i];
125 if (trx_hdr.offsets[i] == 0)
127 part->offset = trx_offset + trx_hdr.offsets[i];
131 for (i = 0; i < trx_nr_parts-1; i++)
132 trx_parts[i].size = trx_parts[i+1].offset - trx_parts[i].offset;
134 trx_parts[i].size = mtd->size - trx_parts[i].offset;
137 part = &trx_parts[i];
138 if (part->size < TRX_MIN_KERNEL_SIZE) {
139 part->name = "loader";
143 part = &trx_parts[i];
144 part->name = "kernel";
147 part = &trx_parts[i];
148 part->name = "rootfs";
150 err = add_mtd_partitions(mtd, trx_parts, trx_nr_parts);
152 printk(KERN_ALERT PFX "adding TRX partitions failed\n");
156 mtd->refresh_device = trxsplit_refresh_partitions;
159 static int trxsplit_refresh_partitions(struct mtd_info *mtd)
161 printk(KERN_INFO PFX "refreshing TRX partitions in '%s' (%d,%d)\n",
162 mtd->name, MTD_BLOCK_MAJOR, mtd->index);
164 /* remove old partitions */
165 del_mtd_partitions(mtd);
167 trxsplit_findtrx(mtd);
171 trxsplit_create_partitions(trx_mtd);
178 static void __init trxsplit_add_mtd(struct mtd_info *mtd)
180 if (mtd->type != MTD_NORFLASH) {
181 printk(KERN_INFO PFX "'%s' is not a NOR flash, skipped\n",
187 trxsplit_findtrx(mtd);
190 static void __init trxsplit_remove_mtd(struct mtd_info *mtd)
195 static struct mtd_notifier trxsplit_notifier __initdata = {
196 .add = trxsplit_add_mtd,
197 .remove = trxsplit_remove_mtd,
200 static void __init trxsplit_scan(void)
202 register_mtd_user(&trxsplit_notifier);
203 unregister_mtd_user(&trxsplit_notifier);
206 static int __init trxsplit_init(void)
211 printk(KERN_INFO PFX "creating TRX partitions in '%s' "
212 "(%d,%d)\n", trx_mtd->name, MTD_BLOCK_MAJOR,
214 trxsplit_create_partitions(trx_mtd);
220 late_initcall(trxsplit_init);