Re: [PATCH 8/8] PCI: qcom: Add support to PCIe slot power supplies

From: Konrad Dybcio
Date: Thu Sep 12 2024 - 10:16:19 EST


On 12.09.2024 3:39 PM, Qiang Yu wrote:
>
> On 9/11/2024 11:32 PM, Manivannan Sadhasivam wrote:
>> On Wed, Sep 11, 2024 at 04:17:41PM +0800, Qiang Yu wrote:
>>> On 8/28/2024 12:58 AM, Manivannan Sadhasivam wrote:
>>>> On Tue, Aug 27, 2024 at 02:44:09PM +0300, Dmitry Baryshkov wrote:
>>>>> On Tue, 27 Aug 2024 at 09:36, Qiang Yu <quic_qianyu@xxxxxxxxxxx> wrote:
>>>>>> On platform x1e80100 QCP, PCIe3 is a standard x8 form factor. Hence, add
>>>>>> support to use 3.3v, 3.3v aux and 12v regulators.
>>>>> First of all, I don't see corresponding bindings change.
>>>>>
>>>>> Second, these supplies power up the slot, not the host controller
>>>>> itself. As such these supplies do not belong to the host controller
>>>>> entry. Please consider using the pwrseq framework instead.
>>>>>
>>>> Indeed. For legacy reasons, slot power supplies were populated in the host
>>>> bridge node itself until recently Rob started objecting it [1]. And it makes
>>>> real sense to put these supplies in the root port node and handle them in the
>>>> relevant driver.
>>>>
>>>> I'm still evaluating whether the handling should be done in the portdrv or
>>>> pwrctl driver, but haven't reached the conclusion. Pwrctl seems to be the ideal
>>>> choice, but I see a few issues related to handling the OF node for the root
>>>> port.
>>>>
>>>> Hope I'll come to a conclusion in the next few days and will update this thread.
>>>>
>>>> - Mani
>>>>
>>>> [1] https://lore.kernel.org/lkml/20240604235806.GA1903493-robh@xxxxxxxxxx/
>>> Hi Mani, do you have any updates?
>>>
>> I'm working with Bartosz to add a new pwrctl driver for rootports. And we are
>> debugging an issue currently. Unfortunately, the progress is very slow as I'm on
>> vacation still.
>>
>> Will post the patches once it got resolved.
>>
>> - Mani
> OK, thanks for your update.

Qiang, you can still resubmit the rest of the patches without having
to wait on that to be resolved

Konrad