[U-Boot] [PATCH v3 07/14] fdt: Add DEV_TREE_BIN option to specify a device tree binary file

[Simon Glass]

Hi Masahiro,

On 9 June 2014 23:59, Masahiro Yamada <yamada.m at jp.panasonic.com> wrote:
> Hi Simon,
>
>
> On Mon,  2 Jun 2014 22:04:50 -0600
> Simon Glass <sjg at chromium.org> wrote:
>
>> In some cases, an externally-built device tree binary is required to be
>> attached to U-Boot. An example is when using image signing, since in that
>> case the .dtb file must include the public keys.
>
> I do not want to expand this argument, but
> I am not sure if DTB stands for "device tree binary".
>
> linux/Documentation often refer it as "device tree blob",
> while   linux/Documentation/devicetree/booting-without-of.txt
> says  "device tree block".
>
>
>> Add a DEV_TREE_BIN option to the Makefile, and update the documentation.
>
> Is it possible to rename it without mentioning  _BIN or _BLOB ?
>
> For example,  DTB_PATH=...   or  EXT_DTB=...
> or some other variable name you like.

I think EXT_DTB is quite a nice name so I've made that change.

>
>
>> diff --git a/Makefile b/Makefile
>> index ece622f..92819bf 100644
>> --- a/Makefile
>> +++ b/Makefile
>> @@ -867,7 +867,7 @@ MKIMAGEFLAGS_u-boot.kwb = -n $(srctree)/$(CONFIG_SYS_KWD_CONFIG:"%"=%) \
>>  MKIMAGEFLAGS_u-boot.pbl = -n $(srctree)/$(CONFIG_SYS_FSL_PBL_RCW:"%"=%) \
>>               -R $(srctree)/$(CONFIG_SYS_FSL_PBL_PBI:"%"=%) -T pblimage
>>
>> -u-boot.img u-boot.kwb u-boot.pbl: u-boot.bin FORCE
>> +u-boot.img u-boot.kwb u-boot.pbl: u-boot$(if $(CONFIG_OF_SEPARATE),-dtb,).bin FORCE
>>       $(call if_changed,mkimage)
>
> The second comma  in   '(if $(CONFIG_OF_SEPARATE),-dtb,)'  is redundant.
>

OK
>
> This is duplicating the same image as  u-boot-dtb.img
>
> Your way is that "u-boot.img" includes DTB in some time and doesn't in the other.
> I am not sure which way is better.
> But we don't need two rules to generate the equivalent image.
>
> If you go along with this change, I think it's OK with me.
> Please consider removing below in that case:
>
>
> ifeq ($(CONFIG_SPL_FRAMEWORK),y)
> ALL-$(CONFIG_OF_SEPARATE) += u-boot-dtb.img
> endif
>
>   and
>
> u-boot-dtb.img: u-boot-dtb.bin FORCE
>         $(call if_changed,mkimage)

I took a look this morning but I'm still not quite sure about this. I
will spend some more time to understand it fully.

Regards,
Simon