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

Dinh Nguyen
2016-11-03T14:21:19Z

On 11/02/2016 03:47 PM, Marek Vasut wrote:
> On 11/02/2016 05:30 PM, Dinh Nguyen wrote:
>> On Tue, Nov 1, 2016 at 3:43 PM, Dinh Nguyen <dinguyen@kernel.org> wrote:
>>>
>>>
>>> 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.
>>>
>>
>> The "reset" functionality is working fine on the SoCKit with 2016.11-rc3.
>
> Does it work on 2016.09.01 too ?
>

Yes...reset works fine on 2016.09.01 and 2016.09 on my SoCKit.

Dinh