[OE-core] [PATCH 2/2] kernel-fitimage.bbclass: Introduce a way to provide external dtb

[Philip Balister]

With these patches, I made a fitImage that booted on the mini-zed. It
would be nice to include a note on how to enable this. I took at few
stabs at it and ended up with

PREFERRED_PROVIDER_virtual/dtb = "devicetree"

in he machine file to get the code to trigger.

Philip

On 02/14/2019 07:56 PM, Manjukumar Matha wrote:
> Currently kernel-fitimage gets the dtb from KERNEL_DEVICETREE, however
> there are instances when the DTB file can be generated using other
> recipes, provide a way to include the DTB instead of inkernel device
> tree.
> 
> Add support for external device tree during the creation of fitimage.
> If virtual/dtb is set then use the path provided in
> EXTERNAL_KERNEL_DEVICETREE else use KERNEL_DEVICETREE during fitimage
> process
> 
> Signed-off-by: Manjukumar Matha <manjukumar.harthikote-matha at xilinx.com>
> ---
>  meta/classes/kernel-fitimage.bbclass | 20 +++++++++++++++++++-
>  1 file changed, 19 insertions(+), 1 deletion(-)
> 
> diff --git a/meta/classes/kernel-fitimage.bbclass b/meta/classes/kernel-fitimage.bbclass
> index 8ebd3dd..3adb1c9 100644
> --- a/meta/classes/kernel-fitimage.bbclass
> +++ b/meta/classes/kernel-fitimage.bbclass
> @@ -30,6 +30,13 @@ python __anonymous () {
>          if image:
>              d.appendVarFlag('do_assemble_fitimage_initramfs', 'depends', ' ${INITRAMFS_IMAGE}:do_image_complete')
>  
> +	#check if there are any dtb providers
> +        providerdtb = d.getVar("PREFERRED_PROVIDER_virtual/dtb")
> +        if providerdtb:
> +            d.appendVarFlag('do_assemble_fitimage', 'depends', ' virtual/dtb:do_populate_sysroot')
> +            d.appendVarFlag('do_assemble_fitimage_initramfs', 'depends', ' virtual/dtb:do_populate_sysroot')
> +            d.setVar('EXTERNAL_KERNEL_DEVICETREE', "${RECIPE_SYSROOT}/boot/devicetree")
> +
>          # Verified boot will sign the fitImage and append the public key to
>          # U-Boot dtb. We ensure the U-Boot dtb is deployed before assembling
>          # the fitImage:
> @@ -373,7 +380,8 @@ fitimage_assemble() {
>  	#
>  	# Step 2: Prepare a DTB image section
>  	#
> -	if [ -n "${KERNEL_DEVICETREE}" ]; then
> +
> +	if [ -z "${EXTERNAL_KERNEL_DEVICETREE}" ] && [ -n "${KERNEL_DEVICETREE}" ]; then
>  		dtbcount=1
>  		for DTB in ${KERNEL_DEVICETREE}; do
>  			if echo ${DTB} | grep -q '/dts/'; then
> @@ -391,6 +399,16 @@ fitimage_assemble() {
>  		done
>  	fi
>  
> +	if [ -n "${EXTERNAL_KERNEL_DEVICETREE}" ]; then
> +		dtbcount=1
> +		for DTBFILE in ${EXTERNAL_KERNEL_DEVICETREE}/*.dtb; do
> +			DTB=`basename ${DTBFILE}`
> +			DTB=$(echo "${DTB}" | tr '/' '_')
> +			DTBS="${DTBS} ${DTB}"
> +			fitimage_emit_section_dtb ${1} ${DTB} ${DTBFILE}
> +		done
> +	fi
> +
>  	#
>  	# Step 3: Prepare a setup section. (For x86)
>  	#
>