On Fri, 6 Dec 2019, at 03:45, Eddie James wrote:
> Document the bindings for the Aspeed AST25XX and AST26XX XDMA engine.
>
> Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>
> Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> Changes since v1:
> - Add 'clocks', 'scu', 'sdmc', 'vga-mem', and 'pcie-device' property
> documentation
>
> .../devicetree/bindings/soc/aspeed/xdma.txt | 43 ++++++++++++++++++++++
> MAINTAINERS | 6 +++
> 2 files changed, 49 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/soc/aspeed/xdma.txt
>
> diff --git a/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> new file mode 100644
> index 0000000..942dc07
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> @@ -0,0 +1,43 @@
> +Aspeed AST25XX and AST26XX XDMA Engine
> +
> +The XDMA Engine embedded in the AST2500 and AST2600 SOCs can perform
> automatic
> +DMA operations over PCI between the SOC (acting as a BMC) and a host
> processor.
> +
> +Required properties:
> + - compatible : must be "aspeed,ast2500-xdma" or
> + "aspeed,ast2600-xdma"
> + - reg : contains the address and size of the memory region
> + associated with the XDMA engine registers
> + - clocks : clock specifier for the clock associated with the
> + XDMA engine
> + - resets : reset specifier for the syscon reset associated with
> + the XDMA engine
> + - interrupts-extended : two interrupt nodes; the first specifies the
s/nodes/cells/?
> global
> + interrupt for the XDMA engine and the second
> + specifies the PCI-E reset or PERST interrupt.
> + - scu : a phandle to the syscon node for the system control
> + unit of the SOC
> + - sdmc : a phandle to the syscon node for the SDRAM memory
> + controller of the SOC
This is a driver and is unrelated to the XDMA hardware. I think we can avoid
touching the SDMC in the XDMA driver anyway (it should be up to the
platform configuration to make sure the remapping is set correctly, not a
behaviour of the XDMA driver).
> + - vga-mem : contains the address and size of the VGA memory space
> + to be used by the XDMA engine
Shouldn't we generalise this to just a 'memory' property? It doesn't have to
be the VGA memory, just we tend to use the VGA memory to uphold security
properties of our platforms.
> +
> +Optional properties:
> + - pcie-device : should be either "bmc" or "vga", corresponding to
> + which device should be used by the XDMA engine for
> + DMA operations. If this property is not set, the XDMA
> + engine will use the BMC PCI-E device.
> +
> +Example:
> +
> + xdma@1e6e7000 {
> + compatible = "aspeed,ast2500-xdma";
> + reg = <0x1e6e7000 0x100>;
> + clocks = <&syscon ASPEED_CLK_GATE_BCLK>;
> + resets = <&syscon ASPEED_RESET_XDMA>;
> + interrupts-extended = <&vic 6>, <&scu_ic
> ASPEED_AST2500_SCU_IC_PCIE_RESET_LO_TO_HI>;
> + scu = <&syscon>;
> + sdmc = <&edac>;
> + pcie-device = "bmc";
> + vga-mem = <0x9f000000 0x01000000>;
> + };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 398861a..528a142 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2707,6 +2707,12 @@ S: Maintained
> F: drivers/media/platform/aspeed-video.c
> F: Documentation/devicetree/bindings/media/aspeed-video.txt
>
> +ASPEED XDMA ENGINE DRIVER
> +M: Eddie James <eajames@xxxxxxxxxxxxx>
> +L: linux-aspeed@xxxxxxxxxxxxxxxx (moderated for non-subscribers)
> +S: Maintained
> +F: Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> +
> ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS
> M: Corentin Chary <corentin.chary@xxxxxxxxx>
> L: acpi4asus-user@xxxxxxxxxxxxxxxxxxxxx
> --
> 1.8.3.1
>
>
