Re: [PATCH v3 0/2] Apple M1 PCIe DT bindings

From: Marc Zyngier
Date: Mon Jul 26 2021 - 06:05:35 EST


On Mon, 26 Jul 2021 09:31:59 +0100,
Mark Kettenis <mark.kettenis@xxxxxxxxx> wrote:
>
> From: Mark Kettenis <kettenis@xxxxxxxxxxx>
>
> This small series adds bindings for the PCIe controller found on the
> Apple M1 SoC.
>
> At this point, the primary consumer for these bindings is U-Boot.
> With these bindings U-Boot can bring up the links for the root ports
> of the PCIe root complex. A simple OS driver can then provide
> standard ECAM access and manage MSI interrupts to provide access
> to the built-in Ethernet and XHCI controllers of the Mac mini.
>
> The Apple controller incorporates Synopsys Designware PCIe logic
> to implement its root port. But unlike other hardware currently
> supported by U-Boot and the Linux kernel the Apple hardware
> integrates multiple root ports. As such the existing bindings
> for the DWC PCIe interface can't be used. There is a single ECAM
> space for all root space, but separate GPIOs to take the PCI devices
> on those ports out of reset. Therefore the standard "reset-gpio" and
> "max-link-speed" properties appear on the child nodes representing
> the PCI devices that correspond to the individual root ports.
>
> MSIs are handled by the PCIe controller and translated into "regular
> interrupts". A range of 32 MSIs is provided. These 32 MSIs can be
> distributed over the root ports as the OS sees fit by programming the
> PCIe controller port registers.
>
> I still hope to hear from Marc Zyngier on the way MSIs are represented
> in this binding.
>
> Patch 2/2 of this series depends on the pinctrl series I sent earlier
> and will probably go through Hector Martin's Apple M1 SoC tree.
>
>
> Changelog:
>
> v3: - Remove unneeded include in example
>
> v2: - Adjust name for ECAM in "reg-names"
> - Drop "phy" registers
> - Expand description
> - Add description for "interrupts"
> - Fix incorrect minItems for "interrupts"
> - Fix incorrect MaxItems for "reg-names"
> - Document the use of "msi-controller", "msi-parent", "iommu-map" and
> "iommu-map-mask"
> - Fix "bus-range" and "iommu-map" properties in the example
>
> Mark Kettenis (2):
> dt-bindings: pci: Add DT bindings for apple,pcie
> arm64: apple: Add PCIe node
>
> .../devicetree/bindings/pci/apple,pcie.yaml | 166 ++++++++++++++++++
> MAINTAINERS | 1 +
> arch/arm64/boot/dts/apple/t8103.dtsi | 63 +++++++
> 3 files changed, 230 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/pci/apple,pcie.yaml

Thanks a log for doing this! For the whole series:

Reviewed-by: Marc Zyngier <maz@xxxxxxxxxx>

M.

--
Without deviation from the norm, progress is not possible.