[U-Boot] [EXT] Re: [PATCH 1/3] arm64: mvebu: Trigger PCI devices scan at early init stage

[Konstantin Porotchkin]

Hi, Simon,

On 04/01/2017 07:23 AM, Simon Glass wrote:
> External Email
>
> ----------------------------------------------------------------------
> Hi Konstanitin,
>
> On 30 March 2017 at 07:58, Konstantin Porotchkin <kostap at marvell.com> wrote:
>>
>>
>> On 03/30/2017 04:31 PM, Stefan Roese wrote:
>>>
>>> (adding Simon to Cc for PCI related question)
>>>
>>> On 28.03.2017 17:36, kostap at marvell.com wrote:
>>>>
>>>> From: Konstantin Porotchkin <kostap at marvell.com>
>>>>
>>>> Add PCIe initialization at early init stage.
>>>> This operation has a side effect of detecting all PCIe
>>>> plug-in cards, so the operator is not obligated to issue
>>>> "pci enum" command though CLI for this purpose.
>>>
>>>
>>> I'm not sure, if this should be handled this way. Simon, how
>>> is such a default PCI scan with DM supposed to get done? Is
>>> there a way do do this automatically without the need that
>>> the user has to issue "pci enum" manually?
>>
>> I was not sure either, but did not see any other way of doing so.
>> I asked to add this change by our Robot/Jenkins automation test team.
>
> It seems reasonable. We actually have some platforms that require PCI
> buses to be probed before we know what devices are in the system, and
> some of these are important.
>
> For example, if your network controller is on PCI then U-Boot will not
> know about it (unless you have it in the device tree) until PCI is
> probed.
>
> I am wondering whether we should add a uclass flag that indicates that
> uclass members should be automatically probed on start-up?
>
> It would not be set for SATA, but would be for PCI.
Thank you for your explanation.
So, as the bottom line - Can I leave the PCIe init call in place and 
remove the SATA devices walk through from this patch?
In my case the PCIe devices should be initialized for detection of a 
network card.

Thanks
Kosta
>
>>>
>>>
>>>> Also convert the SATA first device scan to a walk through
>>>> all availabel SATA devices.
>>>
>>>
>>> This should be done in a separate patch. But seeing this,
>>> won't this SATA / AHCI code be gone completely from this
>>> file, once this is converted into a "real" DM AHCI / SCSI
>>> driver (please look at my preliminary patch for this).
>>
>> Will check your patch, thank you.
>> Maybe this change has to be completely removed if Simon guide me to the
>> right solution for automatic PCIe enumeration.
>>
>
> Regards,
> Simon
>