Re: [PATCH 4/4] use builtin DT for nanopi-neo target

[Jan Kiszka <jan.kiszka@siemens.com>]

On 31.08.23 07:34, MOESSBAUER, Felix (T CED INW-CN) wrote:
> On Tue, 2023-08-08 at 10:48 +0200, Jan Kiszka wrote:
>> On 01.08.23 11:37, Felix Moessbauer wrote:
>>> The upstream kernel still misses the __symbol__ information in the
>>> device tree. By that, overlays cannot be applied (DT was compiled
>>> without -@). However, all u-boot internal device trees are compiled
>>> with
>>> symbol information. By that, just use the one from u-boot.
>>> Note, that the mmclbk entry changed in this device tree (mmclbk2
>>> instead of mmclbk0). This change is reflected in the wks file. An
>>> alternative option would be to use --use-uuid.
>>>
>>
>> I assume you actually booted with that modification, right? Did you
>> check if there are no other differences between the two DTs? They can
>> be
>> subtle as U-Boot is not yet consistently syncing in the kernel DTs
>> for
>> all boards.
> 
> I booted the board with an MTDA image [1] which uses a lot of the
> peripherals of that board. However, I did not do a 1:1 comparison of
> the device tree from u-boot and the kernel.

If all major features of the board still work (networking, storage,
other I/O) and this board is actually looked after in U-Boot as Andre
suggested, then we are good. I was just asking based on past negative
experiences I made.

Jan

> 
> The idea to use the DT from u-boot is based on
> 
> 1. A kernel developer proposed this in [2]
> 2. It showcases the added (but now reverted) builtin_dt=yes support
> 
> In addition, the kernel DT from the stock debian kernel currently
> cannot be used, as this does not support overlays (not compiled with
> symbol information). Back then, it was unclear if the corresponding
> kernel patch to compile with -@ will be accepted and by that this was
> the only feasible solution. Now, the patch from [2] got accepted, but
> there is still no release of the bookworm-backports kernel that
> includes it.
> 
> [1] https://github.com/siemens/mtda
> [2] https://www.spinics.net/lists/devicetree/msg622846.html
> 
> Best regards,
> Felix
> 
>>
>> Jan
>>
>>> Signed-off-by: Felix Moessbauer <felix.moessbauer@siemens.com>
>>> ---
>>>  meta-isar/scripts/lib/wic/canned-wks/nanopi-neo.wks.in | 4 ++--
>>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/meta-isar/scripts/lib/wic/canned-wks/nanopi-neo.wks.in
>>> b/meta-isar/scripts/lib/wic/canned-wks/nanopi-neo.wks.in
>>> index de1c92c4..af5b6f08 100644
>>> --- a/meta-isar/scripts/lib/wic/canned-wks/nanopi-neo.wks.in
>>> +++ b/meta-isar/scripts/lib/wic/canned-wks/nanopi-neo.wks.in
>>> @@ -1,10 +1,10 @@
>>>  #
>>> -# Copyright (c) Siemens AG, 2018
>>> +# Copyright (c) Siemens AG, 2018-2023
>>>  #
>>>  # SPDX-License-Identifier: MIT
>>>
>>>  part u-boot --source rawcopy --sourceparams "file=/usr/lib/u-
>>> boot/nanopi_neo/u-boot-sunxi-with-spl.bin" --no-table --align 8
>>>
>>> -part / --source rootfs-u-boot --ondisk mmcblk0 --fstype ext4 --
>>> mkfs-extraopts "-T default" --label platform --align 1024 --active
>>> +part / --source rootfs-u-boot --ondisk mmcblk2 --fstype ext4 --
>>> mkfs-extraopts "-T default" --sourceparams "builtin_dt=yes" --label
>>> platform --align 1024 --active
>>>
>>>  bootloader --append "rw rootwait"
>>
> 

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