[OE-core] [PATCH v9] kernel-devicetree.bbclass: Add support to generate append to kernel

[Otavio Salvador]

On Thu, Sep 21, 2017 at 11:37 AM, Tom Rini <trini at konsulko.com> wrote:
> On Thu, Sep 21, 2017 at 10:58:33AM -0300, Otavio Salvador wrote:
>
>> The are use cases where the Device Tree appended to the kernel is
>> convinient, so we generate the bundle concatenating the kernel (and
>> potentionally the initramfs) and the Device Tree binaries.
>>
>> To enable it, set KERNEL_DEVICETREE_BUNDLE variable to '1'
>>
>> Signed-off-by: Otavio Salvador <otavio at ossystems.com.br>
> [snip]
>> diff --git a/meta/classes/kernel-devicetree.bbclass b/meta/classes/kernel-devicetree.bbclass
>> index 72814ca224..6e08be4b70 100644
>> --- a/meta/classes/kernel-devicetree.bbclass
>> +++ b/meta/classes/kernel-devicetree.bbclass
>> @@ -1,6 +1,13 @@
>>  # Support for device tree generation
>> -PACKAGES_append = " kernel-devicetree"
>> +PACKAGES_append = " \
>> +    kernel-devicetree \
>> +    ${@['kernel-image-zimage-bundle', ''][d.getVar('KERNEL_DEVICETREE_BUNDLE') != '1']} \
>> +"
>>  FILES_kernel-devicetree = "/${KERNEL_IMAGEDEST}/*.dtb /${KERNEL_IMAGEDEST}/*.dtbo"
>> +FILES_kernel-image-zimage-bundle = "/${KERNEL_IMAGEDEST}/zImage-*.dtb.bin"
>
> Frankly, the most common use case today for still needing to concat the
> dtb to the zImage is for very legacy U-Boot where 'bootz' doesn't exist,
> so we need uImage (which is in turn why we need to patch the kernel
> build process, or manually run mkimage, it must be (zImage + dtb) +
> uImage-header).

There is also the use case of a single binary to boot. We use it in a
customer project and we found it quite useful.

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
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