Re: [PATCH v2 1/4] dt-bindings: imx6q-pcie: Add reg-name "dbi2" and "atu" for i.MX8M PCIe Endpoint

From: Krzysztof Kozlowski
Date: Wed Jul 24 2024 - 02:32:54 EST


On 24/07/2024 08:26, Hongxing Zhu wrote:
>> -----Original Message-----
>> From: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
>> Sent: 2024年7月24日 14:07
>> To: Hongxing Zhu <hongxing.zhu@xxxxxxx>; robh@xxxxxxxxxx;
>> krzk+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx; shawnguo@xxxxxxxxxx;
>> l.stach@xxxxxxxxxxxxxx
>> Cc: devicetree@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx;
>> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
>> kernel@xxxxxxxxxxxxxx; imx@xxxxxxxxxxxxxxx
>> Subject: Re: [PATCH v2 1/4] dt-bindings: imx6q-pcie: Add reg-name "dbi2" and
>> "atu" for i.MX8M PCIe Endpoint
>>
>> On 24/07/2024 05:03, Richard Zhu wrote:
>>> Add reg-name: "dbi2", "atu" for i.MX8M PCIe Endpoint.
>>
>> This we see in the diff. What I do not see is why? Hardware changed? How come?
>>
> For i.MX8M PCIe EP, the dbi2 and atu address are pre-defined in the driver.
> This method is not good.
> In commit b7d67c6130ee ("PCI: imx6: Add iMX95 Endpoint (EP) support"),
> Frank suggests to fetch the dbi2 and atu from DT directly.
> This series is preparation to do that for i.MX8M PCIe EP.

This all must be explained in commit msg.

Anyway, this will be an ABI break, so explain exactly why it is OK to
break the ABI.

Best regards,
Krzysztof