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-rw-r--r--drivers/mtd/afs.c296
1 files changed, 296 insertions, 0 deletions
diff --git a/drivers/mtd/afs.c b/drivers/mtd/afs.c
new file mode 100644
index 00000000000..801e6c7d089
--- /dev/null
+++ b/drivers/mtd/afs.c
@@ -0,0 +1,296 @@
+/*======================================================================
+
+ drivers/mtd/afs.c: ARM Flash Layout/Partitioning
+
+ Copyright (C) 2000 ARM Limited
+
+ 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
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ This is access code for flashes using ARM's flash partitioning
+ standards.
+
+ $Id: afs.c,v 1.13 2004/02/27 22:09:59 rmk Exp $
+
+======================================================================*/
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/init.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/partitions.h>
+
+struct footer_struct {
+ u32 image_info_base; /* Address of first word of ImageFooter */
+ u32 image_start; /* Start of area reserved by this footer */
+ u32 signature; /* 'Magic' number proves it's a footer */
+ u32 type; /* Area type: ARM Image, SIB, customer */
+ u32 checksum; /* Just this structure */
+};
+
+struct image_info_struct {
+ u32 bootFlags; /* Boot flags, compression etc. */
+ u32 imageNumber; /* Unique number, selects for boot etc. */
+ u32 loadAddress; /* Address program should be loaded to */
+ u32 length; /* Actual size of image */
+ u32 address; /* Image is executed from here */
+ char name[16]; /* Null terminated */
+ u32 headerBase; /* Flash Address of any stripped header */
+ u32 header_length; /* Length of header in memory */
+ u32 headerType; /* AIF, RLF, s-record etc. */
+ u32 checksum; /* Image checksum (inc. this struct) */
+};
+
+static u32 word_sum(void *words, int num)
+{
+ u32 *p = words;
+ u32 sum = 0;
+
+ while (num--)
+ sum += *p++;
+
+ return sum;
+}
+
+static int
+afs_read_footer(struct mtd_info *mtd, u_int *img_start, u_int *iis_start,
+ u_int off, u_int mask)
+{
+ struct footer_struct fs;
+ u_int ptr = off + mtd->erasesize - sizeof(fs);
+ size_t sz;
+ int ret;
+
+ ret = mtd->read(mtd, ptr, sizeof(fs), &sz, (u_char *) &fs);
+ if (ret >= 0 && sz != sizeof(fs))
+ ret = -EINVAL;
+
+ if (ret < 0) {
+ printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n",
+ ptr, ret);
+ return ret;
+ }
+
+ ret = 1;
+
+ /*
+ * Does it contain the magic number?
+ */
+ if (fs.signature != 0xa0ffff9f)
+ ret = 0;
+
+ /*
+ * Check the checksum.
+ */
+ if (word_sum(&fs, sizeof(fs) / sizeof(u32)) != 0xffffffff)
+ ret = 0;
+
+ /*
+ * Don't touch the SIB.
+ */
+ if (fs.type == 2)
+ ret = 0;
+
+ *iis_start = fs.image_info_base & mask;
+ *img_start = fs.image_start & mask;
+
+ /*
+ * Check the image info base. This can not
+ * be located after the footer structure.
+ */
+ if (*iis_start >= ptr)
+ ret = 0;
+
+ /*
+ * Check the start of this image. The image
+ * data can not be located after this block.
+ */
+ if (*img_start > off)
+ ret = 0;
+
+ return ret;
+}
+
+static int
+afs_read_iis(struct mtd_info *mtd, struct image_info_struct *iis, u_int ptr)
+{
+ size_t sz;
+ int ret, i;
+
+ memset(iis, 0, sizeof(*iis));
+ ret = mtd->read(mtd, ptr, sizeof(*iis), &sz, (u_char *) iis);
+ if (ret < 0)
+ goto failed;
+
+ if (sz != sizeof(*iis)) {
+ ret = -EINVAL;
+ goto failed;
+ }
+
+ ret = 0;
+
+ /*
+ * Validate the name - it must be NUL terminated.
+ */
+ for (i = 0; i < sizeof(iis->name); i++)
+ if (iis->name[i] == '\0')
+ break;
+
+ if (i < sizeof(iis->name))
+ ret = 1;
+
+ return ret;
+
+ failed:
+ printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n",
+ ptr, ret);
+ return ret;
+}
+
+static int parse_afs_partitions(struct mtd_info *mtd,
+ struct mtd_partition **pparts,
+ unsigned long origin)
+{
+ struct mtd_partition *parts;
+ u_int mask, off, idx, sz;
+ int ret = 0;
+ char *str;
+
+ /*
+ * This is the address mask; we use this to mask off out of
+ * range address bits.
+ */
+ mask = mtd->size - 1;
+
+ /*
+ * First, calculate the size of the array we need for the
+ * partition information. We include in this the size of
+ * the strings.
+ */
+ for (idx = off = sz = 0; off < mtd->size; off += mtd->erasesize) {
+ struct image_info_struct iis;
+ u_int iis_ptr, img_ptr;
+
+ ret = afs_read_footer(mtd, &img_ptr, &iis_ptr, off, mask);
+ if (ret < 0)
+ break;
+ if (ret == 0)
+ continue;
+
+ ret = afs_read_iis(mtd, &iis, iis_ptr);
+ if (ret < 0)
+ break;
+ if (ret == 0)
+ continue;
+
+ sz += sizeof(struct mtd_partition);
+ sz += strlen(iis.name) + 1;
+ idx += 1;
+ }
+
+ if (!sz)
+ return ret;
+
+ parts = kmalloc(sz, GFP_KERNEL);
+ if (!parts)
+ return -ENOMEM;
+
+ memset(parts, 0, sz);
+ str = (char *)(parts + idx);
+
+ /*
+ * Identify the partitions
+ */
+ for (idx = off = 0; off < mtd->size; off += mtd->erasesize) {
+ struct image_info_struct iis;
+ u_int iis_ptr, img_ptr, size;
+
+ /* Read the footer. */
+ ret = afs_read_footer(mtd, &img_ptr, &iis_ptr, off, mask);
+ if (ret < 0)
+ break;
+ if (ret == 0)
+ continue;
+
+ /* Read the image info block */
+ ret = afs_read_iis(mtd, &iis, iis_ptr);
+ if (ret < 0)
+ break;
+ if (ret == 0)
+ continue;
+
+ strcpy(str, iis.name);
+ size = mtd->erasesize + off - img_ptr;
+
+ /*
+ * In order to support JFFS2 partitions on this layout,
+ * we must lie to MTD about the real size of JFFS2
+ * partitions; this ensures that the AFS flash footer
+ * won't be erased by JFFS2. Please ensure that your
+ * JFFS2 partitions are given image numbers between
+ * 1000 and 2000 inclusive.
+ */
+ if (iis.imageNumber >= 1000 && iis.imageNumber < 2000)
+ size -= mtd->erasesize;
+
+ parts[idx].name = str;
+ parts[idx].size = size;
+ parts[idx].offset = img_ptr;
+ parts[idx].mask_flags = 0;
+
+ printk(" mtd%d: at 0x%08x, %5dKB, %8u, %s\n",
+ idx, img_ptr, parts[idx].size / 1024,
+ iis.imageNumber, str);
+
+ idx += 1;
+ str = str + strlen(iis.name) + 1;
+ }
+
+ if (!idx) {
+ kfree(parts);
+ parts = NULL;
+ }
+
+ *pparts = parts;
+ return idx ? idx : ret;
+}
+
+static struct mtd_part_parser afs_parser = {
+ .owner = THIS_MODULE,
+ .parse_fn = parse_afs_partitions,
+ .name = "afs",
+};
+
+static int __init afs_parser_init(void)
+{
+ return register_mtd_parser(&afs_parser);
+}
+
+static void __exit afs_parser_exit(void)
+{
+ deregister_mtd_parser(&afs_parser);
+}
+
+module_init(afs_parser_init);
+module_exit(afs_parser_exit);
+
+
+MODULE_AUTHOR("ARM Ltd");
+MODULE_DESCRIPTION("ARM Firmware Suite partition parser");
+MODULE_LICENSE("GPL");
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