How to obtain preloader with yocto meta-altera layer

I Installed yocto and meta-altera layer. Did run a bitbake core-image-minimal, which created a kernel, rootfs and u-boot in de deploy folder.

The only parts which is missing is the preloader. When checking the work folder for u-boot ( version 2016.05 )
an spl seems to be build: ( files in …/socfpga_cyclone5_defconfig/spl/ : u-boot-spl.bin, u-boot-spl.sfp, u-boot-spl-nodtb.bin )

On some forum discussion I found the following:
“If you upgrade to the U-Boot 2016.01 (or maybe even earlier?), mkimage
actually supports adding the Bootrom signature to the SPL for you. The
current makefile is kind enough to concatenate the U-Boot SPL and its DTS
for you, and then run mkpimage to create an ‘spl/u-boot-spl-dts.sfp’ file”

Some questions I still have:

  1. Are the fles in the u-boot tree in /socfpga_cyclone5_defconfig/spl/* the dorrect files for the spl ?
  2. Why am I missing the spl in the deploy directory ?
  3. What is the sfp file ?
  4. Is there somewhere an explanation how to create an sdcard image by using the meta-altera layer ?
  5. How to customize the layer (bbappend ? ) for using different handover files ?
  6. It seems an old yocto install from altera had some script, which is not present in meta-altera. Did I miss soemthing in my install ? What is the official sourec for this script ?

Note: I found out that adding image type sdcard creates and sdcard image, however using the generated sdcard on a Cyclone V altera SOC development kit board does event not start u-boot. Is teh default configuration not correct ?

Any help would be appreciated,