[meta-freescale] Freescale Linux kernel 3.10.17_1.0.0_beta

[Otavio Salvador]

John,

On Mon, Dec 30, 2013 at 6:32 PM, John Weber <rjohnweber at gmail.com> wrote:
> On 12/30/13 2:17 PM, Otavio Salvador wrote:
>>
>> On Mon, Dec 30, 2013 at 5:51 PM, Fabio Estevam <festevam at gmail.com> wrote:
>>>
>>> On Mon, Dec 30, 2013 at 5:37 PM, John Weber <rjohnweber at gmail.com> wrote:
>>>
>>>>> I think this is a great idea but I believe we ought to make this for
>>>>> all boards so we have it uniform across the boards; otherwise we'll
>>>>> have a mix and it makes the support harder.
>>>
>>> Yes, in mainline U-boot I plan to convert them all at once.
>>
>> Please do one commit per board; so it is easier to revert (if needed).
>>
>>>>> Considering we'd target this for 1.6, what would be the conversion
>>>>> plan?
>>>>>
>>>>> Who could be responsible for each board for converting/testing?
>>>>>
>>>> Not sure, my thought was to leave it to the board maintainers. Unless
>>>> I'm
>>>> mistaken (which is a possibility), for some reason uImage does not work
>>>> when
>>>> booting with the 3.10.X kernels.  It that is the case then we either
>>>> need to
>>>> figure out the problem with uImages or others will be forced to use
>>>> zImage
>>>> anyway.
>>>
>>> I managed to boot FSL imx_3.10.9_1.0.0_alpha with mainline U-boot.
>>
>> Me too; All customer-kernels I've been doing (based on 3.10) been
>> using zImage and it works quite well. Did you test older kernels
>> (3.0.35 and 2.6.35, for example)?
>
> Right now, all my zImage attempts have been made using 3.10.17 beta, but I
> plan to go back and do 3.0.35.  I shall stay away from 2.6.35.  :-)

Good; this would be 'good enough' for us to consider the migration of
Wandboard for zImage.

>>> Haven't tested imx_3.10.17_1.0.0_beta yet, but I can try it next week.
>>>
>>> Even if we manage to get imx_3.10.17_1.0.0_beta booting fine with
>>> uImage, I still think that booting the zImage makes sense, as it can
>>> avoid user errors by passing incorrect LOADADDR.
>>
>> I like this as a goal but this is not a simple change for the BSP; we
>> need to make it work for both supported kernels and test both. The
>> ideal would be to have all boards using zImage but we have a long way
>> for this...
>
> It does seem like a rather large change.  For each board, the changes are
> fairly minimal (as long as it works), but when you figure in 30+ boards, and
> for custom boards, that is a whole different problem.  I'd like to know what
> other maintainers think here.

Yes; I fully agree. We cannot underestimate this change as it has a
high impact the BSP.

>> Even if we convert all boards to zImage we need to keep support for
>> uImage as customers may be using it for their internal boards.
>>
> Assuming that the default images filenames would be 'uImage' and 'zImage'
> one could do a hack-ish thing like test to see which file is present and
> then either bootz or bootm based on that.  I actually did half of this
> earlier today (minus the testing which file is present), by selecting bootz
> when image=zImage, and bootm when image=uImage.  While this would be nice to
> make it work by default with uImage or zImage, it is not very elegant and
> would need to repeated for each board config file, therefore it is a hack.
> It would be much better for a simple 'bootany' command to test which type of
> image is loaded into memory and pick the appropriate one.

Yes; this was the ugly hack I was talking about ;-)

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
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