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

Christopher Covington cov at codeaurora.org
Fri Mar 6 07:09:36 PST 2015


On 03/05/2015 09:28 PM, Rob Clark wrote:
> On Thu, Mar 5, 2015 at 8:59 PM, Olof Johansson <olof at lixom.net> wrote:
>> On Thu, Mar 5, 2015 at 12:23 PM, Kumar Gala <galak at codeaurora.org> wrote:
>>>
>>> On Mar 5, 2015, at 1:42 PM, Kevin Hilman <khilman at kernel.org> wrote:
>>>
>>>> Kumar Gala <galak at 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 at vger.kernel.org>
>>>>> Signed-off-by: Kumar Gala <galak at 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?
>>
> 
> I never managed to figure out how to get that to work (at least on my
> apq8074 dragonboard.. fortunately ifc6540 seems to work w/ appended
> dtb).. kind of a pita because it is a bit of a non-standard boot.img
> format too..

I think you're talking about the boot flow from plain poweron which I wish I
knew more about, but in case it's any help, here are some fastboot boot steps
what worked for me a while back.

http://elinux.org/Dragonboard/APQ8074

Chris

-- 
Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project



More information about the linux-arm-kernel mailing list