[U-Boot] [RFC PATCH 00/10] sunxi: Allwinner A64 SPL support

[Alexander Graf]

On 11/03/2016 10:51 AM, Andre Przywara wrote:
> Hi,
>
> On 03/11/16 09:34, Hans de Goede wrote:
>> <Adding Peter Robinson to the Cc to see how much he will
>>   object my packaging ideas>
>>
>> Hi,
>>
>> First of all cool stuff! Thank you Andre and all others
>> involved for making this happen.
>>
>> On 03-11-16 09:49, Alexander Graf wrote:
>>> On 11/03/2016 02:36 AM, Andre Przywara wrote:
>>>> Hi,
>>>>
>>>> this is my first take on the SPL support for the Allwinner A64 SoC.
>>>> The actual meat - the DRAM initialization code - has been provided
>>>> by Jens - many thanks for that!
>>>> The rest of the patches mostly deal with the 32-bit/64-bit switch.
>>>>
>>>> While it is possible and seems natural to let the SPL also run in
>>>> 64-bit,
>>>> this creates a really large binary (32600 Bytes in my case). With some
>>>> hacks (plus some fixes to make the SPL 64-bit safe) I got this to work,
>>> So how about we merge the 64bit version first (since that's *way*
>>> easier to compile for everyone) and then consider the move to 32bit
>>> afterwards? I don't even want to start to imagine how to squeeze a
>>> 32bit SPL build into the build process for our U-Boot binaries.
>>>
>>>> but any addition will probably break it and exceed the 32KB limit that
>>>> the BROM imposes. Debug is the first obvious victim here.
>>> Do you have some section size comparisons between the two?
>> Later down in the mail Andre says that in 32 bit (thumb) mode
>> the size goes down to 20KB which gives us a lot more head-room
>> then the 32600 out of 32768 bytes available for the 64 bit
>> version.
>>
>> With that said I agree with you (Alex) that having a 32 bit
>> SPL + 64 bit u-boot proper is worry-some from a distro pov.
> What's even nastier is the requirement of a cross compiler even for a
> native build. Do Fedora and Suse offer packaged cross-compilers for the
> other ARM bitness, respectively?

Andreas Faerber was working on cross compilers in openSUSE, but I don't 
think they're part of the distribution yet.


Alex