device tree blob must be 4-bytes alingned

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 <[email protected]> Signed-off-by: Piotr Wilczek <[email protected]> Signed-off-by: Kyungmin Park <[email protected]>
zonque · Dec 18, 2013 · ec09d8a · ec09d8a
1 parent 1e29caa
commit ec09d8a
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diff --git 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
@@ -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;