[PATCH 3/8] device tree blob must be 4-bytes alingned
Piotr Wilczek
p.wilczek at samsung.com
Wed Dec 11 08:07:34 EST 2013
Each appended device tree blob must be 4-bytes aligned.
This patch modifies append_dtbs script to append bytes to each device tree
file so the size is multiple of 4.
When finding dtb the addres of next dtb is also aligned to 4-bytes.
Signed-off-by: Tomasz Figa <t.figa at samsung.com>
Signed-off-by: Piotr Wilczek <p.wilczek at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
---
append_dtbs.sh | 11 +++++++++++
dtbs.c | 4 ++++
2 files changed, 15 insertions(+)
diff --git a/append_dtbs.sh b/append_dtbs.sh
index 82bb463..a8a7cda 100755
--- a/append_dtbs.sh
+++ b/append_dtbs.sh
@@ -4,5 +4,16 @@ OUT="$1"
shift
DTBS="$*"
+while [ -n "$*" ]
+do
+ SIZE=`stat $1 -c %s`
+ MOD=`expr $SIZE % 4`
+ if [ $MOD -ne 0 ]; then
+ PADDING=`expr 4 - $MOD`
+ dd if=/dev/zero count=$PADDING bs=1 >> $1 2> /dev/null
+ fi
+ shift
+done
+
cat $DTBS >>$OUT
dd if=/dev/zero of=$OUT oflag=append conv=notrunc bs=1 count=8 #sentinel
diff --git a/dtbs.c b/dtbs.c
index 812c2ef..26e3b83 100644
--- a/dtbs.c
+++ b/dtbs.c
@@ -30,6 +30,10 @@ void *find_dtb(void *dtbs, const char *compat)
return d;
d = (struct fdt_header *)((char *)d + be_to_cpu(d->totalsize));
+
+ /* align to 4-bytes */
+ d = (struct fdt_header *)((((unsigned int)d + 0x3) & ~0x3));
+
}
return NULL;
--
1.7.9.5
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