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

Dinh Nguyen
2016-11-01T20:43:30Z

On 11/01/2016 03:42 PM, Marek Vasut wrote:
> On 11/01/2016 09:39 PM, Dinh Nguyen wrote:
>>
>>
>> On 11/01/2016 03:09 PM, Marek Vasut wrote:
>>> On 11/01/2016 04:43 PM, Dinh Nguyen wrote:
>>>>
>>>>
>>>> On 10/29/2016 02:59 PM, Marek Vasut wrote:
>>>>> On 10/18/2016 05:50 PM, Dinh Nguyen wrote:
>>>>>> On Sun, Oct 16, 2016 at 10:59 AM, Marek Vasut <marex@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.
>>>>>
>>>>
>>>> Can I ask what board are you seeing this on? I'm seeing that on my Atlas
>>>> board, it does not reset properly(even with the patch reverted). But
>>>> "reset" is working fine on my devkit, with and without the patch.
>>>
>>> SoCKit and MCVEVK.
>>>
>>> I tried bisecting it, it worked on 2016.07 and doesn't on 2016.09 , and
>>> I arrived at this patch. Maybe you can double-check this ?
>>>
>>
>> Okay, I can check it on the SoCKit.
>
> It also happens on MCVEVK, but that's probably moot for your test ;-)
>

I don't have an MCVEVK.

Dinh