[U-Boot] [RFC] 0/4] Add Pl330 DMA support

[Marek Vasut]

On 10/18/2016 05:50 PM, Dinh Nguyen wrote:
> On Sun, Oct 16, 2016 at 10:59 AM, Marek Vasut <marex at denx.de> wrote:
>> On 10/15/2016 12:10 AM, Dinh Nguyen wrote:
>>>
>>>
>>> On 10/10/2016 10:52 AM, Dinh Nguyen wrote:
>>>> Hi,
>>>>
>>>> This patchset adds the PL330 DMA driver to U-Boot. The SoCFPGA platform makes
>>>> use of the PL330 to transfer zereos to the SDRAM which enables the ECC bit.
>>>>
>>>> This is only an RFC because after rebasing to v2016.11-rc1, I had to revert
>>>> the following patch "a78cd8613204 ARM: Rework and correct barrier definitions"
>>>> in order for this patch set to work correctly. With the above patch applied,
>>>> after the SDRAM scrubbing is complete, the SPL is failing to find the MMC
>>>> device.
>>>>
>>>
>>> I kinda figured out why patch "a78cd8613204 ARM: Rework and correct
>>> barrier definitions" is causing SPL to fail after the SDRAM scrub
>>> operation. It appears that before the above mentioned patch, the dmb()
>>> operation is defined as this:
>>>
>>> #define dmb()          __asm__ __volatile__ ("" : : : "memory")
>>>
>>> after the patch, the dmb is now:
>>>
>>> #define DMB    asm volatile ("dmb sy" : : : "memory")
>>>
>>> So the "dmb sy" as described in the ARM documentation is a "Full system
>>> DMB operation". For whatever reason, this change is causing the SPL
>>> error after the SDRAM scrub operation.
>>
>> Thanks for looking into this, can you poke into it some more ?
>>
> 
> Of course..

The patch is causing a failure even in normal operation -- if you boot
the socfpga board and type "reset", it won't reset with the patch.

-- 
Best regards,
Marek Vasut