diff options
| -rw-r--r-- | drivers/mtd/parsers/afs.c | 158 |
1 files changed, 157 insertions, 1 deletions
diff --git a/drivers/mtd/parsers/afs.c b/drivers/mtd/parsers/afs.c index 72c688b8a383..0c730024f806 100644 --- a/drivers/mtd/parsers/afs.c +++ b/drivers/mtd/parsers/afs.c @@ -3,6 +3,7 @@ drivers/mtd/afs.c: ARM Flash Layout/Partitioning Copyright © 2000 ARM Limited + Copyright (C) 2019 Linus Walleij This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -35,6 +36,8 @@ #include <linux/mtd/partitions.h> #define AFSV1_FOOTER_MAGIC 0xA0FFFF9F +#define AFSV2_FOOTER_MAGIC1 0x464C5348 /* "FLSH" */ +#define AFSV2_FOOTER_MAGIC2 0x464F4F54 /* "FOOT" */ struct footer_v1 { u32 image_info_base; /* Address of first word of ImageFooter */ @@ -68,6 +71,22 @@ static u32 word_sum(void *words, int num) return sum; } +static u32 word_sum_v2(u32 *p, u32 num) +{ + u32 sum = 0; + int i; + + for (i = 0; i < num; i++) { + u32 val; + + val = p[i]; + if (val > ~sum) + sum++; + sum += val; + } + return ~sum; +} + static bool afs_is_v1(struct mtd_info *mtd, u_int off) { /* The magic is 12 bytes from the end of the erase block */ @@ -88,6 +107,27 @@ static bool afs_is_v1(struct mtd_info *mtd, u_int off) return (magic == AFSV1_FOOTER_MAGIC); } +static bool afs_is_v2(struct mtd_info *mtd, u_int off) +{ + /* The magic is the 8 last bytes of the erase block */ + u_int ptr = off + mtd->erasesize - 8; + u32 foot[2]; + size_t sz; + int ret; + + ret = mtd_read(mtd, ptr, 8, &sz, (u_char *)foot); + if (ret < 0) { + printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n", + ptr, ret); + return false; + } + if (ret >= 0 && sz != 8) + return false; + + return (foot[0] == AFSV2_FOOTER_MAGIC1 && + foot[1] == AFSV2_FOOTER_MAGIC2); +} + static int afs_parse_v1_partition(struct mtd_info *mtd, u_int off, struct mtd_partition *part) { @@ -185,6 +225,113 @@ static int afs_parse_v1_partition(struct mtd_info *mtd, return 0; } +static int afs_parse_v2_partition(struct mtd_info *mtd, + u_int off, struct mtd_partition *part) +{ + u_int ptr; + u32 footer[12]; + u32 imginfo[36]; + char *name; + u32 version; + u32 entrypoint; + u32 attributes; + u32 region_count; + u32 block_start; + u32 block_end; + u32 crc; + size_t sz; + int ret; + int i; + int pad = 0; + + pr_debug("Parsing v2 partition @%08x-%08x\n", + off, off + mtd->erasesize); + + /* First read the footer */ + ptr = off + mtd->erasesize - sizeof(footer); + ret = mtd_read(mtd, ptr, sizeof(footer), &sz, (u_char *)footer); + if ((ret < 0) || (ret >= 0 && sz != sizeof(footer))) { + pr_err("AFS: mtd read failed at 0x%x: %d\n", + ptr, ret); + return -EIO; + } + name = (char *) &footer[0]; + version = footer[9]; + ptr = off + mtd->erasesize - sizeof(footer) - footer[8]; + + pr_debug("found image \"%s\", version %08x, info @%08x\n", + name, version, ptr); + + /* Then read the image information */ + ret = mtd_read(mtd, ptr, sizeof(imginfo), &sz, (u_char *)imginfo); + if ((ret < 0) || (ret >= 0 && sz != sizeof(imginfo))) { + pr_err("AFS: mtd read failed at 0x%x: %d\n", + ptr, ret); + return -EIO; + } + + /* 32bit platforms have 4 bytes padding */ + crc = word_sum_v2(&imginfo[1], 34); + if (!crc) { + pr_debug("Padding 1 word (4 bytes)\n"); + pad = 1; + } else { + /* 64bit platforms have 8 bytes padding */ + crc = word_sum_v2(&imginfo[2], 34); + if (!crc) { + pr_debug("Padding 2 words (8 bytes)\n"); + pad = 2; + } + } + if (crc) { + pr_err("AFS: bad checksum on v2 image info: %08x\n", crc); + return -EINVAL; + } + entrypoint = imginfo[pad]; + attributes = imginfo[pad+1]; + region_count = imginfo[pad+2]; + block_start = imginfo[20]; + block_end = imginfo[21]; + + pr_debug("image entry=%08x, attr=%08x, regions=%08x, " + "bs=%08x, be=%08x\n", + entrypoint, attributes, region_count, + block_start, block_end); + + for (i = 0; i < region_count; i++) { + u32 region_load_addr = imginfo[pad + 3 + i*4]; + u32 region_size = imginfo[pad + 4 + i*4]; + u32 region_offset = imginfo[pad + 5 + i*4]; + u32 region_start; + u32 region_end; + + pr_debug(" region %d: address: %08x, size: %08x, " + "offset: %08x\n", + i, + region_load_addr, + region_size, + region_offset); + + region_start = off + region_offset; + region_end = region_start + region_size; + /* Align partition to end of erase block */ + region_end += (mtd->erasesize - 1); + region_end &= ~(mtd->erasesize -1); + pr_debug(" partition start = %08x, partition end = %08x\n", + region_start, region_end); + + /* Create one partition per region */ + part->name = kstrdup(name, GFP_KERNEL); + if (!part->name) + return -ENOMEM; + part->offset = region_start; + part->size = region_end - region_start; + part->mask_flags = 0; + } + + return 0; +} + static int parse_afs_partitions(struct mtd_info *mtd, const struct mtd_partition **pparts, struct mtd_part_parser_data *data) @@ -200,6 +347,10 @@ static int parse_afs_partitions(struct mtd_info *mtd, sz += sizeof(struct mtd_partition); i += 1; } + if (afs_is_v2(mtd, off)) { + sz += sizeof(struct mtd_partition); + i += 1; + } } if (!i) @@ -213,13 +364,18 @@ static int parse_afs_partitions(struct mtd_info *mtd, * Identify the partitions */ for (i = off = 0; off < mtd->size; off += mtd->erasesize) { - if (afs_is_v1(mtd, off)) { ret = afs_parse_v1_partition(mtd, off, &parts[i]); if (ret) goto out_free_parts; i++; } + if (afs_is_v2(mtd, off)) { + ret = afs_parse_v2_partition(mtd, off, &parts[i]); + if (ret) + goto out_free_parts; + i++; + } } *pparts = parts; |