[U-Boot] SoCFPGA PL330 DMA driver and ECC scrubbing

[Jason Rush <jarush@gmail.com>]

On 6/29/2018 9:34 AM, Marek Vasut wrote:
> On 06/29/2018 04:31 PM, Jason Rush wrote:
>> Dinh,
> Hi,
>
>> A while ago, you posted the following patchset for SoCFPGA to add the PL330
>> DMA driver, and updated the SoCFPGA SDRAM init to write zeros to SDRAM to
>> initialize the ECC bits if ECC was enabled:
>>
>> https://lists.denx.de/pipermail/u-boot/2016-October/269643.html
>>
>> I know it's been a long time, so I'll summarize some of the conversation...
>>
>> At the time, you had a problem with the patchset causing the SPL to fail to
>> find the MMC.  You had tracked it down to an issue with the following commit
>> "a78cd8613204 ARM: Rework and correct barrier definitions".  You and Marek
>> discussed it a bit, but I don't think there was a real conclusion.  You
>> submitted a second version of the patchset asking for advice on debugging
>> the issue:
>>
>> https://lists.denx.de/pipermail/u-boot/2016-December/275822.html
>>
>> No real conversation came from the second patchset, and that was the end of
>> the patch.
>>
>> I was hoping we could revisit adding your patchset again. I am working on a
>> custom SoCFPGA board with a Cyclone V and ECC SDRAM. I rebased your patchset
>> against v2018.05 and it is working on my custom board (although I don't have
>> an MMC). I also tested it on a SoCKit booting from an MMC (I forced it to
>> scrub the SDRAM on the SoCKit, because it doesn't have ECC RAM), and the
>> SoCKit finds the MMC and boots.
>>
>> I don't have any suggestions on why it is working now on my board and not
>> back when you first submitted the patchset.  Maybe something else was fixed
>> in the MMC? I was hoping you and Marek could test this patch again on some
>> different SoCFPGA boards to see if you get the same results.
> Look at this patch
> http://git.denx.de/?p=u-boot/u-boot-socfpga.git;a=commit;h=9bb8a249b292d26f152c20e3641600b3d7b3924b
>
> You likely want similar approach, it's faster then the DMA and much simpler.
>
Thanks Marek.  I'll give it a try.  Would you be interested in a similar patch for the Gen 5?

Jason