Re: [PATCH v3 3/5] arm64: dts: agilex: add dtsi for PCIe Root Port

[Bjorn Helgaas <helgaas@kernel.org>]

On Wed, Jan 08, 2025 at 02:53:50PM -0800, matthew.gerlach@linux.intel.com wrote:
> On Wed, 8 Jan 2025, Bjorn Helgaas wrote:
> > On Wed, Jan 08, 2025 at 10:59:07AM -0600, Matthew Gerlach wrote:
> > > Add the base device tree for support of the PCIe Root Port
> > > for the Agilex family of chips.
> > > 
> > > Signed-off-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
> > > ---
> > > v3:
> > >  - Remove accepted patches from patch set.
> > > 
> > > v2:
> > >  - Rename node to fix schema check error.
> > > ---
> > >  .../intel/socfpga_agilex_pcie_root_port.dtsi  | 55 +++++++++++++++++++
> > >  1 file changed, 55 insertions(+)
> > >  create mode 100644 arch/arm64/boot/dts/intel/socfpga_agilex_pcie_root_port.dtsi
> > > 
> > > diff --git a/arch/arm64/boot/dts/intel/socfpga_agilex_pcie_root_port.dtsi b/arch/arm64/boot/dts/intel/socfpga_agilex_pcie_root_port.dtsi
> > > new file mode 100644
> > > index 000000000000..50f131f5791b
> > > --- /dev/null
> > > +++ b/arch/arm64/boot/dts/intel/socfpga_agilex_pcie_root_port.dtsi
> > > @@ -0,0 +1,55 @@
> > > +// SPDX-License-Identifier:     GPL-2.0
> > > +/*
> > > + * Copyright (C) 2024, Intel Corporation
> > > + */
> > > +&soc0 {
> > > +	aglx_hps_bridges: fpga-bus@80000000 {
> > > +		compatible = "simple-bus";
> > > +		reg = <0x80000000 0x20200000>,
> > > +		      <0xf9000000 0x00100000>;
> > > +		reg-names = "axi_h2f", "axi_h2f_lw";
> > > +		#address-cells = <0x2>;
> > > +		#size-cells = <0x1>;
> > > +		ranges = <0x00000000 0x00000000 0x80000000 0x00040000>,
> > > +			 <0x00000000 0x10000000 0x90100000 0x0ff00000>,
> > > +			 <0x00000000 0x20000000 0xa0000000 0x00200000>,
> > > +			 <0x00000001 0x00010000 0xf9010000 0x00008000>,
> > > +			 <0x00000001 0x00018000 0xf9018000 0x00000080>,
> > > +			 <0x00000001 0x00018080 0xf9018080 0x00000010>;
> > > +
> > > +		pcie_0_pcie_aglx: pcie@200000000 {
> > > +			reg = <0x00000000 0x10000000 0x10000000>,
> > > +			      <0x00000001 0x00010000 0x00008000>,
> > > +			      <0x00000000 0x20000000 0x00200000>;
> > > +			reg-names = "Txs", "Cra", "Hip";
> > > +			interrupt-parent = <&intc>;
> > > +			interrupts = <GIC_SPI 0x14 IRQ_TYPE_LEVEL_HIGH>;
> > > +			interrupt-controller;
> > > +			#interrupt-cells = <0x1>;
> > > +			device_type = "pci";
> > > +			bus-range = <0x0000000 0x000000ff>;
> > 
> > I don't think this bus-range is needed since
> > pci_parse_request_of_pci_ranges() defaults to 00-ff when bus-range is
> > absent.
> 
> Yes, pci_parse_request_of_pci_ranges() does default to using 00-ff when the
> bus-range property is absent. Removing the bus-range property does result in
> an extra kernel message at startup:
>     No bus range found for ...,using [bus 00-ff].
> 
> If the extra kernel message is not a problem, then removing the bus-range
> property does result in a smaller device tree.

Interesting, I think we should remove that message.