[PATCH v2 1/3] devicetree: bindings: Document qcom, msm-id and qcom, board-id

Kumar Gala
2015-03-10T17:13:46Z

On Mar 9, 2015, at 7:11 AM, Arnd Bergmann <arnd@arndb.de> wrote:

> On Friday 06 March 2015 14:37:52 Kumar Gala wrote:
>> On Mar 6, 2015, at 1:15 PM, Olof Johansson <olof@lixom.net> wrote:
>>
>>> On Fri, Mar 6, 2015 at 8:08 AM, Kumar Gala <galak@codeaurora.org> wrote:
>>>>
>>>> On Mar 5, 2015, at 7:59 PM, Olof Johansson <olof@lixom.net> wrote:
>>>>
>>>>> On Thu, Mar 5, 2015 at 12:23 PM, Kumar Gala <galak@codeaurora.org> wrote:
>>>>>>
>>>>>> On Mar 5, 2015, at 1:42 PM, Kevin Hilman <khilman@kernel.org> wrote:
>>>>>>
>>>>>>> Kumar Gala <galak@codeaurora.org> writes:
>>>>>>>
>>>>>>>> The top level qcom,msm-id and qcom,board-id are utilized by bootloaders
>>>>>>>> on Qualcomm MSM platforms to determine which device tree should be
>>>>>>>> utilized and passed to the kernel.
>>>>>>>>
>>>>>>>> Cc: <devicetree@vger.kernel.org>
>>>>>>>> Signed-off-by: Kumar Gala <galak@codeaurora.org>
>>>>>>>
>>>>>>> Is this the special magic that allows qcom bootloaders to take a kernel
>>>>>>> plus multiple DTBs and figure out which DTB to pass?
>>>>>>>
>>>>>>> Kevin
>>>>>>
>>>>>> yes
>>>>>
>>>>> That's a bummer.
>>>>>
>>>>> Luckily, the solution for upstream is still quite simple: Provide only
>>>>> one devicetree, and it'll be used, right?
>>>>
>>>> We can provide only one, we still need the IDs in the DT.
>>>
>>> How are the DTS provided? Concatenated with the kernel, or in a
>>> wrapped data format? Or in a separate partition from the kernel?
>>
>> Its a wrapped data format that is than concatenated with the kernel if I remember correctly.
>
> Then you should be able to create a tool that can write this concatenated
> format and insert these properties from a table that matches the boot
> loader, right?
>
> Arnd

Are you suggesting the tool insert the properties in the DT? I?m not sure I understand what the point of doing that would be.

- k