Re: [PATCH v4 0/4] Apple M1 PCIe DT bindings

From: Marc Zyngier
Date: Tue Sep 21 2021 - 07:01:43 EST


On Fri, 27 Aug 2021 18:15:25 +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.
>
> This now adds an MSI controller binding schema and uses the generic
> msi-ranges property to specify how the MSIs are mapped to interrupts
> on the AIC. I copied some of the description text in the MSI
> controller binding schema from msi.txt but it may need some further
> tweaks to make sense.
>
> 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:
>
> v4: - Convert MSI controller binding to YAML
> - Add generic msi-ranges property to MSI controller binding
> - Fix typos/formatting in apple,pcie binding
> - Use generic MSI controller binding in apple,pcie
>
> 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 (4):
> dt-bindings: interrupt-controller: Convert MSI controller to
> json-schema
> dt-bindings: interrupt-controller: msi: Add msi-ranges property
> dt-bindings: pci: Add DT bindings for apple,pcie
> arm64: apple: Add PCIe node
>
> .../interrupt-controller/msi-controller.yaml | 42 +++++
> .../devicetree/bindings/pci/apple,pcie.yaml | 165 ++++++++++++++++++
> .../bindings/pci/brcm,stb-pcie.yaml | 1 +
> .../bindings/pci/microchip,pcie-host.yaml | 1 +
> MAINTAINERS | 1 +
> arch/arm64/boot/dts/apple/t8103.dtsi | 63 +++++++
> 6 files changed, 273 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/interrupt-controller/msi-controller.yaml
> create mode 100644 Documentation/devicetree/bindings/pci/apple,pcie.yaml

With Rob's comments addressed, and the fix on the M1 RC MMIO region,
for the whole series:

Acked-by: Marc Zyngier <maz@xxxxxxxxxx>

M.

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