Re: Freescale Linux kernel 3.10.17_1.0.0_beta

[John Weber <rjohnweber@gmail.com>]

Hi Otavio -

On 12/30/13 2:17 PM, Otavio Salvador wrote:
> On Mon, Dec 30, 2013 at 5:51 PM, Fabio Estevam <festevam@gmail.com> wrote:
>> On Mon, Dec 30, 2013 at 5:37 PM, John Weber <rjohnweber@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.  :-)
>> 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.
>
> 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.

John