Linux PCI subsystem development
 help / color / mirror / Atom feed
From: Florian Fainelli <florian.fainelli@broadcom.com>
To: Andrea della Porta <andrea.porta@suse.com>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Broadcom internal kernel review list
	<bcm-kernel-feedback-list@broadcom.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-rpi-kernel@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org,
	iivanov@suse.de, svarbanov@suse.de, mbrugger@suse.com,
	Phil Elwell <phil@raspberrypi.com>
Subject: Re: [PATCH 0/4] Fix RP1 DeviceTree hierarchy and drop overlay support
Date: Thu, 18 Dec 2025 11:11:00 -0800	[thread overview]
Message-ID: <8cbf63d2-1510-4d58-b2ca-0fd23a476539@broadcom.com> (raw)
In-Reply-To: <cover.1766077285.git.andrea.porta@suse.com>

On 12/18/25 11:09, Andrea della Porta wrote:
> The current RP1 implementation is plagued by several issues, as follows:
> 
> - the node name for RP1 is too specific and should be generic instead
>    (see [1]).
> 
> - the fully defined DTS has its PCI hierarchy wrongly described. There
>    should be a PCI root port between the root complex and the endpoint
>    (see [1]).
> 
> - since CONFIG_PCI_DYNAMIC_OF_NODES can be dropped in the future
>    becoming an automatically enabled feature, it would be wise to not
>    depend on it (see [2]).
> 
> - overlay support has led to a lot of confusion. It's not really usable
>    right now and users are not even used to it (see [3]).
> 
> This patch aims at solving the aforementioned problems by amending the
> PCI topology as follows:
> 
>    ...
>    pcie@1000120000 {
>      ...
> 
>      pci@0,0 {
>        device_type = "pci";
>        reg = <0x00 0x00 0x00 0x00 0x00>;
>        ...
> 
>        dev@0,0 {
>          compatible = "pci1de4,1";
>          reg = <0x10000 0x00 0x00 0x00 0x00>;
>          ...
> 
>          pci-ep-bus@1 {
>            compatible = "simple-bus";
>            ...
> 
>            /* peripherals child nodes */
>          };
>        };
>      };
>    };
> 
> The reg property is important since it permits the binding the OF
> device_node structure to the pci_dev, encoding the BDF in the upper
> portion of the address.
> 
> This patch also drops the overlay support in favor of the fully
> described DT while streamlining it as a result.

Timing could not have been better as I was just going to apply Rob's patch:

https://lore.kernel.org/all/20251211193854.1778221-1-robh@kernel.org

Yours is definitively more complete. Rob, Krzysztof, can you review this 
series and I will fast track it today.

Thanks!
-- 
Florian

  parent reply	other threads:[~2025-12-18 19:11 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-12-18 19:09 [PATCH 0/4] Fix RP1 DeviceTree hierarchy and drop overlay support Andrea della Porta
2025-12-18 19:09 ` [PATCH 1/4] dt-bindings: misc: pci1de4,1: add required reg property for endpoint Andrea della Porta
2025-12-19 20:41   ` Florian Fainelli
2025-12-18 19:09 ` [PATCH 2/4] misc: rp1: drop overlay support Andrea della Porta
2025-12-19 20:41   ` Florian Fainelli
2025-12-18 19:09 ` [PATCH 3/4] arm64: dts: broadcom: bcm2712: fix RP1 endpoint PCI topology Andrea della Porta
2025-12-19 20:41   ` Florian Fainelli
2025-12-18 19:09 ` [PATCH 4/4] arm64: dts: broadcom: rp1: drop RP1 overlay Andrea della Porta
2025-12-19 20:41   ` Florian Fainelli
2025-12-18 19:11 ` Florian Fainelli [this message]
2025-12-19 15:25 ` [PATCH 0/4] Fix RP1 DeviceTree hierarchy and drop overlay support Rob Herring

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=8cbf63d2-1510-4d58-b2ca-0fd23a476539@broadcom.com \
    --to=florian.fainelli@broadcom.com \
    --cc=andrea.porta@suse.com \
    --cc=bcm-kernel-feedback-list@broadcom.com \
    --cc=bhelgaas@google.com \
    --cc=conor+dt@kernel.org \
    --cc=devicetree@vger.kernel.org \
    --cc=iivanov@suse.de \
    --cc=krzk+dt@kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linux-rpi-kernel@lists.infradead.org \
    --cc=mbrugger@suse.com \
    --cc=phil@raspberrypi.com \
    --cc=robh@kernel.org \
    --cc=svarbanov@suse.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox