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Message-ID: <458ce909-0616-487d-b4bd-42b58d059198@linaro.org>
Date: Thu, 11 Apr 2024 08:01:37 +0200
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Subject: Re: [PATCH v2 2/4] dt-bindings: PCI: mediatek,mt7621: add missing
 child node reg
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
 Lorenzo Pieralisi <lpieralisi@kernel.org>,
 =?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= <kw@linux.com>,
 Rob Herring <robh@kernel.org>, Krzysztof Kozlowski <krzk+dt@kernel.org>,
 Conor Dooley <conor+dt@kernel.org>, Hector Martin <marcan@marcan.st>,
 Sven Peter <sven@svenpeter.dev>, Alyssa Rosenzweig <alyssa@rosenzweig.io>,
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 Broadcom internal kernel review list
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References: <20240410212638.GA2159326@bhelgaas>
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From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
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In-Reply-To: <20240410212638.GA2159326@bhelgaas>
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On 10/04/2024 23:26, Bjorn Helgaas wrote:
> On Wed, Apr 10, 2024 at 08:15:19PM +0200, Krzysztof Kozlowski wrote:
>> MT7621 PCI host bridge has children which apparently are also PCI host
>> bridges, at least that's what the binding suggest.
> 
> What does it even mean for a PCI host bridge to have a child that is
> also a PCI host bridge?
> 
> Does this mean a driver binds to the "parent" host bridge, enumerates
> the PCI devices below it, and finds a "child" host bridge?

I think the question should be towards Mediatek folks. I don't know what
this hardware is exactly, just looks like pci-pci-bridge. The driver
calls the children host bridges as "ports".

Best regards,
Krzysztof