Building kernel for more than one SoC

[Robert Nelson]

On Mon, Aug 11, 2014 at 4:15 PM, Grant Edwards
<grant.b.edwards at gmail.com> wrote:
> On 2014-08-11, Russell King - ARM Linux <linux at arm.linux.org.uk> wrote:
>> On Mon, Aug 11, 2014 at 08:43:35PM +0000, Grant Edwards wrote:
>>> On 2014-08-11, Robert Nelson <robertcnelson at gmail.com> wrote:
>>> >> Now it's up to somebody else to decide if the price difference between
>>> >> a G20 and G25 is worth the engineering time to upgrade U-Boot and
>>> >> Linux kernel to versions that know about device trees...
>>> >
>>> > http://cateee.net/lkddb/web-lkddb/ARM_APPENDED_DTB.html
>>>
>>> Interesting.  That would still require modifying U-Boot so that at
>>> run-time it detects the SoC type and appends the proper DTB to the
>>> kernel image, but it that may be less work than "real" DTB support in
>>> U-Boot.
>>
>> The idea of that feature is:
>>
>> - You take the kernel zImage
>> - You take the appropriate dtb file
>> - You concatenate the dtb file into the zImage
>> - You run mkimage on the resulting combined image to create the special
>>   uboot format file for uboot to load
>
> The problem is now you've got a kernel image that won't run on both
> the '9g20 and the '9g25.  The requirement is to have a kernel image
> that will run on either.

Then, upgrade your u-boot to mainline, use the dtb, etc.  You have a
lot of excuses. ;)

Regards,

-- 
Robert Nelson
http://www.rcn-ee.com/