[PATCH 2/3] clk: shmobile: Add MSTP clock support

[Kumar Gala]

On Oct 29, 2013, at 9:55 AM, Laurent Pinchart wrote:

> MSTP clocks are gate clocks controlled through a register that handles
> up to 32 clocks. The register is often sparsely populated.
> 
> Those clocks are found on Renesas ARM SoCs.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
> ---
> .../bindings/clock/renesas,cpg-mstp-clocks.txt     |  47 +++++
> drivers/clk/shmobile/Makefile                      |   1 +
> drivers/clk/shmobile/clk-mstp.c                    | 229 +++++++++++++++++++++
> include/dt-bindings/clock/r8a7790-clock.h          |  56 +++++
> 4 files changed, 333 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt
> create mode 100644 drivers/clk/shmobile/clk-mstp.c
> create mode 100644 include/dt-bindings/clock/r8a7790-clock.h
> 
> diff --git a/Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt
> new file mode 100644
> index 0000000..b3a1ce0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt
> @@ -0,0 +1,47 @@
> +* Renesas R8A7790 MSTP Clocks

can we spell out MSTP once in the heading?

> +
> +The CPG can gate SoC device clocks. The gates are organized in groups of up to
> +32 gates.
> +
> +This device tree binding describes a single 32 gate clocks group per node.
> +Clocks are referenced by user nodes by the MSTP node phandle and the clock
> +index in the group, from 0 to 31.
> +
> +Required Properties:
> +
> +  - compatible: Must be one of the following
> +    - "renesas,r8a7790-mstp-clocks" for R8A7790 (R-Car H2) MSTP gate clocks
> +    - "renesas,cpg-mstp-clock" for generic MSTP gate clocks
> +  - reg: Base address and length of the memory resource used by the MSTP
> +    clocks
> +  - clocks: Reference to the parent clocks
> +  - #clock-cells: Must be 1
> +  - clock-output-names: The name of the clocks as free-form strings
> +  - renesas,indices: Index of the gate clocks (0 to 31)

Index of the gate clock into what?

> +
> +The clocks, clock-output-names and renesas,indices properties contain one
> +entry per gate. The MSTP groups are sparsely populated. Unimplemented gates

per gate clock. (?)

> +must not be declared.
> +
> +
> +Example
> +-------
> +
> +	#include <dt-bindings/clock/r8a7790-clock.h>
> +
> +	mstp3_clks: mstp3_clks {
> +		compatible = "renesas,r8a7790-mstp-clocks", "renesas,cpg-mstp-clocks";
> +		reg = <0 0xe615013c 0 4>, <0 0xe6150048 0 4>;
> +		clocks = <&cp_clk>, <&mmc1_clk>, <&sd3_clk>, <&sd2_clk>,
> +			 <&cpg_clocks R8A7790_CLK_SD1>, <&cpg_clocks R8A7790_CLK_SD0>,
> +			 <&mmc0_clk>;
> +		#clock-cells = <1>;
> +		clock-output-names =
> +			"tpu0", "mmcif1", "sdhi3", "sdhi2",
> +			 "sdhi1", "sdhi0", "mmcif0";
> +		renesas,clock-indices = <
> +			R8A7790_CLK_TPU0 R8A7790_CLK_MMCIF1 R8A7790_CLK_SDHI3
> +			R8A7790_CLK_SDHI2 R8A7790_CLK_SDHI1 R8A7790_CLK_SDHI0
> +			R8A7790_CLK_MMCIF0
> +		>;
> +	};

- k

-- 
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