[LEDE-DEV] ar71xx kernel size starts getting oversized

[Yousong Zhou]

                yousong


On 17 June 2016 at 16:28, John Crispin <john at phrozen.org> wrote:
>
>
> On 17/06/2016 10:10, Yousong Zhou wrote:
>> On 4 June 2016 at 12:49, Yousong Zhou <yszhou4tech at gmail.com> wrote:
>>> Several days ago I tried to build a firmware for HiWiFi-HC6361 with
>>> LEDE master branch.  Yet the firmware was not present in
>>> bin/targets/ar71xx/generic after the build completed.  I checked the
>>> downloads.lede-project.org the firmware was also missing there.
>>>
>>> The problem is that mtdparts layout of HC6361 requires the kernel part
>>> to be not bigger than 1280KB (1310720 bytes).  Yet the lzma-compressed
>>> kernel uImage has exceeded this size limit.
>>>
>>> The current size of lede-ar71xx-generic-uImage-lzma.bin in
>>> downloads.lede-project.org is 1367988
>>>
>>> The corresponding file in OpenWrt downloads site are as follows
>>>
>>>     snapshot         1295637
>>>     15.05.1            1176662
>>>     14.07               1107048
>>>
>>> My device is currently running 4.1.16 with OpenWrt r48975.  So the
>>> bloat probably comes from the 4.4 bump.  Sorry that at the moment I
>>> can just bring the issue up and cannot find time to do further
>>> investigation.
>>
>> Comparing config-4.1 before the bump with config-4.4, and config-3.10
>> from bb branch and config-4.4, it seems that the size increase
>> probably comes from Open Firmware device tree support recently
>> introduced to ath79 mach  :(
>>
>>                 yousong
>>
>>>
>>> Regards
>>>
>>>                 yousong
>>
>
> i plan to work on converting the target to full dts support after the
> release. this will safe us around 25k of mach files and platform code in
> the kernel
>
>         John

It should be possible to lift the size limit on kernel and rootfs part
with mtdsplit.  I will git it a try and see if it can catch up with
the release schedule :)

                yousong