[PATCH 2/4] Documentation: dt: misc: Add Aspeed ast2400/2500 LPC Control bindings

[Rob Herring]

On Thu, Jan 12, 2017 at 11:29:08AM +1100, Cyril Bur wrote:
> Signed-off-by: Cyril Bur <cyrilbur at gmail.com>
> ---
>  .../devicetree/bindings/misc/aspeed-lpc-ctrl.txt   | 78 ++++++++++++++++++++++
>  1 file changed, 78 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/misc/aspeed-lpc-ctrl.txt
> 
> diff --git a/Documentation/devicetree/bindings/misc/aspeed-lpc-ctrl.txt b/Documentation/devicetree/bindings/misc/aspeed-lpc-ctrl.txt
> new file mode 100644
> index 000000000000..f84ac83211ec
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/aspeed-lpc-ctrl.txt
> @@ -0,0 +1,78 @@
> +ASpeed LPC Control
> +==================
> +This binding defines the LPC control for ASpeed SoCs. Partitions of
> +the LPC bus can be access by other processors on the system, address
> +ranges on the bus can map accesses from another processor to regions
> +of the ASpeed SoC memory space.
> +
> +Reserved Memory:
> +================
> +The driver provides functionality to map the LPC bus to a region of
> +ASpeed ram. A phandle to a reserved memory node must be provided so
> +that the driver can safely use this region.
> +
> +Flash:
> +======
> +The driver provides functionality to unmap the LPC bus from ASpeed
> +RAM, historically the default mapping has been to the SPI flash
> +controller on the ASpeed SoC, a phandle to this node should be
> +supplied.
> +
> +Device Node:
> +============
> +
> +As LPC bus configuration registers are at the start of the LPC bus
> +memory space, it makes most sense for the device to be within the LPC
> +host node. See Documentation/devicetree/bindings/mfd/aspeed-lpc.txt
> +for more information. This does not have to be the case, provided the
> +reg property can give the full address of the LPC bus.

Same comment here.

> +
> +Required properties:
> +--------------------
> +
> +- compatible:		"aspeed,ast2400-lpc-ctrl" for ASpeed ast2400 SoCs
> +					"aspeed,ast2500-lpc-ctrl" for ASpeed ast2500 SoCs
> +
> +- reg:				Location and size of the configuration registers
> +					for the LPC bus. Note that if the device node is
> +					within the LPC host node then base is relative to
> +					that.
> +
> +- memory-region:	phandle of the reserved memory region
> +- flash:			phandle of the SPI flash controller
> +
> +Example:
> +--------
> +
> +reserved-memory {
> +	#address-cells = <1>;
> +	#size-cells = <1>;
> +	ranges;
> +
> +	...
> +
> +	flash_memory: region at 54000000 {
> +		compatible = "aspeed,ast2400-lpc-ctrl";

This doesn't look right?

> +		no-map;
> +		reg = <0x54000000 0x04000000>; /* 64M */

Is this system RAM? reserved-memory is generally for carveouts in system 
RAM (e.g. the memory node).

> +	};
> +};
> +
> +host_pnor: spi at 1e630000 {
> +	reg = < 0x1e630000 0x18
> +			0x30000000 0x02000000 >;
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +	compatible = "aspeed,ast2400-smc";
> +
> +	...
> +
> +};
> +
> +lpc-ctrl at 0 {
> +	compatible = "aspeed,ast2400-lpc-ctrl";
> +	memory-region = <&flash_memory>;
> +	flash = <&host_pnor>;
> +	reg = <0x0 0x80>;
> +};
> +
> -- 
> 2.11.0
>