image_types_fsl.bbclass: use a sparse file for sdcard generation

This speeds up the generation of the sdcard and reduces the amount of
space used for it.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Reported-by: "John Passaniti" <jpassaniti@ashly.com>

diff --git a/meta-fsl-arm/classes/image_types_fsl.bbclass b/meta-fsl-arm/classes/image_types_fsl.bbclass
index d9e292c69cd48674fd3597078b9d9448b63aaa2e..5d213e51a04ae69788f504d9c1a7545df0ac6bc3 100644 (file)
--- a/meta-fsl-arm/classes/image_types_fsl.bbclass
+++ b/meta-fsl-arm/classes/image_types_fsl.bbclass
@@ -53,7 +53,8 @@ IMAGE_CMD_sdcard () {
        TMP=${WORKDIR}/tmp
        SDCARD=${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.sdcard
 
-       dd if=/dev/zero of=${SDCARD} bs=$(expr 1000 \* 1000) count=${SDCARD_SIZE}
+       # Initialize a sparse file
+       dd if=/dev/zero of=${SDCARD} bs=1 count=0 seek=$(expr 1000 \* 1000 \* ${SDCARD_SIZE})
 
        # Create partition table
        parted -s ${SDCARD} mklabel msdos