[PATCH v8 1/5] dt-bindings: soc: Add Aspeed XDMA Engine
andrew at aj.id.au
Sun Apr 5 17:10:33 AEST 2020
On Sat, 4 Apr 2020, at 02:58, Eddie James wrote:
> Document the bindings for the Aspeed AST25XX and AST26XX XDMA engine.
> Signed-off-by: Eddie James <eajames at linux.ibm.com>
> Reviewed-by: Rob Herring <robh at kernel.org>
> Reviewed-by: Andrew Jeffery <andrew at aj.id.au>
> Changes since v6:
> - Add PCI-E root complex reset documentation
> - Add reset-names documentation
> - Switch to memory-region phandle instead of memory regs
> .../devicetree/bindings/soc/aspeed/xdma.txt | 44 +++++++++++++++++++
> MAINTAINERS | 6 +++
> 2 files changed, 50 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> diff --git a/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> new file mode 100644
> index 000000000000..c3d7cdeb1db6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> @@ -0,0 +1,44 @@
> +Aspeed AST25XX and AST26XX XDMA Engine
> +The XDMA Engine embedded in the AST2500 and AST2600 SOCs can perform
> +DMA operations over PCI between the SOC (acting as a BMC) and a host
> +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, and, for the AST2600, a second reset
> + associated with the PCI-E root complex
> + - reset-names : required only for the AST2600; must be "dev, "rc"
Bit of a nit, but I find "root-complex" to not be so onerous as to shorten it to "rc".
Is there a need to be so economical? Contracting it makes it harder to read.
While we're here we might also expand "dev" to "device".
Also you're missing the closing quote on "dev".
> + - interrupts-extended : two interrupt cells; the first specifies the
> + interrupt for the XDMA engine and the second
> + specifies the PCI-E reset or PERST interrupt.
> + - aspeed,scu : a phandle to the syscon node for the system control
> + unit of the SOC
> + - memory-region : a phandle to the reserved memory region to be used
> + the XDMA engine for DMA operations
Might have been worth dropping the tags for this patch given the changes. I
feel Rob will welcome the switch to describing the memory with a phandle
to a reserved region, but removing his tag makes it easier for him to protest :)
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