[U-Boot] [PATCH 10/10] ARM: socfpga: arria10: add support for building Arria10

[Dinh Nguyen <dinguyen@opensource.altera.com>]

On 11/23/2015 05:20 PM, Marek Vasut wrote:
> On Tuesday, November 24, 2015 at 12:04:10 AM, Dinh Nguyen wrote:
>> On 11/23/2015 05:03 PM, Marek Vasut wrote:
>>> On Monday, November 23, 2015 at 11:50:15 PM, Dinh Nguyen wrote:
>>>> On 11/23/2015 04:46 PM, Marek Vasut wrote:
>>>>> On Monday, November 23, 2015 at 11:32:27 PM, Dinh Nguyen wrote:
>>>>> [...]
>>>>>
>>>>>>>>>> The main point is that we need to program the FPGA
>>>>>>>>>> during U-Boot booting up with a ~>10 MB rbf file while being
>>>>>>>>>> limited to the OCRAM's size. I would like to contain this
>>>>>>>>>> ugliness in it's own directory.
>>>>>>>>>
>>>>>>>>> What's the problem with this ? We already support loading files
>>>>>>>>> from storage in SPL, so just compile the FPGA manager into SPL as
>>>>>>>>> well and use it.
>>>>>>>>
>>>>>>>> Ok, let me re-work it all under the c5/a5 directory. Thanks for
>>>>>>>> reviewing.
>>>>>>>
>>>>>>> But you didn't really answer my question -- what is the problem with
>>>>>>> the FPGA loader in SPL ?
>>>>>>
>>>>>> I thought you've already answered your own question. For whatever
>>>>>> reason, the downstream A10 is re-doing the FPGA manager just for this
>>>>>> purpose.
>>>>>
>>>>> Could the reason be that the FPGA manager in it's current state expects
>>>>> one big buffer with the entire FPGA bitstream ? When you're in SPL and
>>>>> you still don't have DRAM running, you cannot create such buffer
>>>>> anywhere. Thus, what you need to do is to have some sort of code which
>>>>> loads a bit of the bitstream file at time and feeds it into the FPGA
>>>>> manager, piece by piece. This should be doable pretty easily, what do
>>>>> you think ?
>>>>
>>>> That's exactly what is being in the mach-socfpga directory.
>>>
>>> Um, am I missing it in this patchset ?
>>
>> No, you're not missing it, I have not sent it up yet. That support is in
>> the downstream, but also with the fpga-manager driver re-written. I need
>> to clean this up before I can send it.
> 
> OK, thanks :)
> 
>>>> Yes, but should that code go into mach-socfpga or drivers?
>>>
>>> The FPGA manager bits are already in drivers/fpga/ , so that's where the
>>> improvements should go. If you need some special handling in the SPL,
>>> that should be in mach-socfpga . In case it's too much change to the
>>> current SPL, moving the spl.c to spl-gen5.c and creating new spl-gen10.c
>>> might make sense ... or something like that, possibly even with some
>>> spl-common.c .
>>
>> Ok. BTW, Arria10 is not using SPL. It has 256K of OCRAM that U-Boot can
>> use to setup the SDRAM.
> 
> So what do I do if I want to boot arria10 from NAND ? UBI and UBIFS won't
> fit into 256kiB, so I think using SPL might be the sensible thing afterall,
> since you would be able to use arbitrarily-sized U-Boot.
> 

I hope Chin Liang can chime here, I know that we have support for NAND,
but I haven't been part of that task, so I don't know how it's being done.

Dinh