[PATCH v5 4/5] ARM: dts: mt8135: enable basic SMP bringup for mt8135

[Kevin Hilman]

Hi Eddie,

Eddie Huang <eddie.huang at mediatek.com> writes:

> On Tue, 2015-11-10 at 17:16 -0800, Kevin Hilman wrote:
>> Hi Eddie,
>> 
>> [...]
>> 
>> > I check the log [0],
>> 
>> Thanks for checking into this boot failure.
>> 
>> > it seems first time mt8135-evbp1 boot to kernel
>> > shell successfully, then boot again. In the second time, mt8135 stay in
>> > fastboot mode, waiting host send boot image, then timeout.
>> 
>> Actually, it never gets to a shell the first time.  If you look closely,
>> the target reboots as soon as userspace starts.   Look for the PYBOOT
>> line which says "finished booting, starting userspace"
>> 
>> Later on, pyboot thinks it finds a root shell due to finding '#'
>> characters, but clearly it never got to a shell.
>> 
>> > I download zImage and dtb in [1], and kernel run to shell successfully
>> > on my platform.
>> 
>> Are you can you try using a ramdisk as well?  You can use the pre-built
>> one here:
>> http://storage.kernelci.org/images/rootfs/buildroot/armel/rootfs.cpio.gz
>> 
>
> Yes, I tried this ramdisk, and I can reproduce fail issue.
>

OK, good.   Thanks for looking into it.

>> Please check my boot logs to see how I'm generating the boot.img file
>> (search for mkbootimg) with a kernel/dtb/ramdisk.  It may be possible
>> that the kernel image size with a ramdisk is breaking some of the
>> assumptions in the fastboot mode.  I've seen problems like this on other
>> platforms due to hard-coded sizes/addresses in the boot firmware.
>> 
>
> MT8135 allocate 10MB for BOOT partition, but the test boot.img is 11MB,
> thus cause user space fail.

Aha, I was right!  ;)

> I will prepare new firmware that extend BOOT
> partition to 16MB. and put new firmware on Howard's github. I will mail
> to you when I am ready..

Great, thanks for working on this.

Any chance of making it even bigger?  We're working on running some more
automated testing from a ramdisk, and those ramdisks will be easily
30-50 Mb with modules included and a rootfs with extra tests.

Kevin