[PATCH 1/9] microblaze: dts: Use the normal build rule

[Michal Simek]

On 12/28/23 15:26, Tom Rini wrote:
> On Thu, Dec 28, 2023 at 01:37:49PM +0000, Simon Glass wrote:
>> Hi Tom,
>>
>> On Wed, Dec 27, 2023 at 1:20 PM Tom Rini <trini at konsulko.com> wrote:
>>>
>>> On Wed, Dec 27, 2023 at 08:23:57AM +0000, Simon Glass wrote:
>>>> Build devicetree files using the normal SoC-generic rule. For
>>>> microblaze there is actually only one SoC and one board.
>>>>
>>>> Signed-off-by: Simon Glass <sjg at chromium.org>
>>>> ---
>>>>
>>>>   arch/microblaze/dts/Makefile | 2 +-
>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/arch/microblaze/dts/Makefile b/arch/microblaze/dts/Makefile
>>>> index 427a8f9aaca..adc76ddf21f 100644
>>>> --- a/arch/microblaze/dts/Makefile
>>>> +++ b/arch/microblaze/dts/Makefile
>>>> @@ -1,6 +1,6 @@
>>>>   # SPDX-License-Identifier: GPL-2.0+
>>>>
>>>> -dtb-y += $(shell echo $(CONFIG_DEFAULT_DEVICE_TREE)).dtb
>>>> +dtb-$(CONFIG_MICROBLAZE) += microblaze-generic.dtb
>>>>
>>>>   include $(srctree)/scripts/Makefile.dts
>>>
>>> This (and nios2 and perhaps a few other arches) show that it would be
>>> easier to just drop the dts- line as it adds nothing over what
>>> scripts/Makefile.dts gives us.
>>
>> For consistency I like to see a rule for each .dtb in the directory.
> 
> Yes, and for consistency I'd like to see Makefiles be as minimal as
> required.
> 
>>> I wonder how this will interact with
>>> OF_UPSTREAM and how it compares with arch/microblaze/boot/dts/system.dts
>>> in the linux kernel.
>>
>> I don't see any interaction. Perhaps the maintainer can move this to
>> OF_UPSTREAM?
> 
> Well, that's the big question here, how exactly does microblaze work
> with device trees? The U-Boot one is basically empty. I think we're both
> going to be waiting on Michal now :)

U-Boot and Linux DT is just for reference. There is no really golden DT to use. 
Every design is different and I am fine with completely remove their content but 
I would like to keep just one empty DT as we have now in u-boot.
The reason is that when you have your own design and you want to test it quickly 
you can just cp your new file over microblaze-generic.dts with existing makefile 
rule and build u-boot with OF embed and just test it.

In Linux there is very old DT and I should likely remove it completely. It 
targets designed which were used a lot of years ago and definitely not passing 
any dt schema validation.

Thanks,
Michal