Re: [PATCH v1 0/5] PolarFire SoC Icicle Reference Design PCIe ?support?/fixes

["Rob Herring (Arm)" <robh@kernel.org>]

On Mon, 10 Jun 2024 12:09:12 +0100, Conor Dooley wrote:
> Hey all,
> 
> Here's some patches that add an Erratum to enable non-coherent DMA
> support for PolarFire SoC. By nature of being an FPGA, and due to the
> PCIe root ports being only 32-bit capable, many bitstreams configure the
> FPGA fabric such that peripherals in the fabric become non-coherent. The
> PCIe root ports on PolarFire SoC are connected to the core-complex via
> the fabric, and therefore can be (and regularly are) made DMA
> non-coherent. The Icicle Kit Reference Design has been configuring the
> PCIe root port in this manner since late 2022 and in a way unsupported
> by mainline since earlier that year. Adding this non-coherent DMA
> support makes PCIe functional on those FPGA designs. Daire did almost all
> the work to figure out how to support these kinds of designs, and this
> series depends on his patches to introduce the required dma-ranges
> handling for the root port driver:
> https://lore.kernel.org/linux-pci/20240531085333.2501399-1-daire.mcnamara@microchip.com/
> 
> The final patch depends on:
> https://lore.kernel.org/linux-pci/20240527-slather-backfire-db4605ae7cd7@wendy/
> 
> I'm not sure if an Erratum is really the right way to go about doing
> this, but I didn't want to make ARCH_MICROCHIP depend on NONPORTABLE.
> An alternative would be to add a menu under drivers/soc like Renesas
> does and allow it to be toggled as an option there instead.
> 
> Thanks,
> Conor.
> 
> CC: Paul Walmsley <paul.walmsley@sifive.com>
> CC: Palmer Dabbelt <palmer@dabbelt.com>
> CC: Conor Dooley <conor.dooley@microchip.com>
> CC: Daire McNamara <daire.mcnamara@microchip.com>
> CC: Rob Herring <robh@kernel.org>
> CC: Krzysztof Kozlowski <krzk+dt@kernel.org>
> CC: Samuel Holland <samuel.holland@sifive.com>
> CC: linux-riscv@lists.infradead.org
> CC: devicetree@vger.kernel.org
> 
> Conor Dooley (5):
>   cache: ccache: allow building for PolarFire
>   cache: ccache: add mpfs to nonstandard cache ops list
>   RISC-V: Add an MPFS erratum for PCIe
>   riscv: dts: microchip: modify memory map & add dma-ranges for pcie on
>     icicle
>   riscv: dts: microchip: update pcie reg properties
> 
>  arch/riscv/Kconfig.errata                     | 19 +++++
>  .../dts/microchip/mpfs-icicle-kit-fabric.dtsi | 77 ++++++++++++-------
>  .../boot/dts/microchip/mpfs-icicle-kit.dts    | 44 +++++++++--
>  .../dts/microchip/mpfs-m100pfs-fabric.dtsi    |  6 +-
>  .../dts/microchip/mpfs-polarberry-fabric.dtsi |  6 +-
>  drivers/cache/Kconfig                         |  2 +-
>  drivers/cache/sifive_ccache.c                 |  2 +
>  7 files changed, 116 insertions(+), 40 deletions(-)
> 
> --
> 2.43.2
> 
> 
> 


My bot found new DTB warnings on the .dts files added or changed in this
series.

Some warnings may be from an existing SoC .dtsi. Or perhaps the warnings
are fixed by another series. Ultimately, it is up to the platform
maintainer whether these warnings are acceptable or not. No need to reply
unless the platform maintainer has comments.

If you already ran DT checks and didn't see these error(s), then
make sure dt-schema is up to date:

  pip3 install dtschema --upgrade


New warnings running 'make CHECK_DTBS=y microchip/mpfs-icicle-kit.dtb' for 20240610-vertical-frugally-a92a55427dd9@wendy:

arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dtb: pcie@3000000000: reg: [[48, 0, 0, 134217728], [0, 1124106240, 0, 8192], [0, 1124114432, 0, 8192]] is too long
	from schema $id: http://devicetree.org/schemas/pci/microchip,pcie-host.yaml#
arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dtb: pcie@3000000000: reg-names:1: 'apb' was expected
	from schema $id: http://devicetree.org/schemas/pci/microchip,pcie-host.yaml#
arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dtb: pcie@3000000000: reg-names: ['cfg', 'bridge', 'ctrl'] is too long
	from schema $id: http://devicetree.org/schemas/pci/microchip,pcie-host.yaml#
arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dtb: pcie@3000000000: Unevaluated properties are not allowed ('#address-cells', '#interrupt-cells', '#size-cells', 'bus-range', 'device_type', 'dma-noncoherent', 'interrupt-controller', 'interrupt-map', 'interrupt-map-mask', 'interrupt-parent', 'interrupts', 'msi-parent', 'reg', 'reg-names' were unexpected)
	from schema $id: http://devicetree.org/schemas/pci/microchip,pcie-host.yaml#