On Tue, Feb 28, 2017 at 11:06:58PM +0800, Leo Yan wrote:
> According to ARMv8 architecture reference manual (ARM DDI 0487A.k)
> Chapter 'Part H: External debug', the CPU can integrate debug module
> and it can support self-hosted debug and external debug. Especially
> for supporting self-hosted debug, this means the program can access
> the debug module from mmio region; and usually the mmio region is
> integrated with coresight.
>
> So add document for binding debug component, includes binding to APB
> clock; and also need specify the CPU node which the debug module is
> dedicated to specific CPU.
>
> Suggested-by: Mike Leach <mike.le...@linaro.org>
> Signed-off-by: Leo Yan <leo....@linaro.org>
> ---
> .../devicetree/bindings/arm/coresight-debug.txt | 40
> ++++++++++++++++++++++
> 1 file changed, 40 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/arm/coresight-debug.txt
>
> diff --git a/Documentation/devicetree/bindings/arm/coresight-debug.txt
> b/Documentation/devicetree/bindings/arm/coresight-debug.txt
> new file mode 100644
> index 0000000..89820d5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/coresight-debug.txt
> @@ -0,0 +1,40 @@
> +* CoreSight Debug Component:
> +
> +CoreSight debug component are compliant with the ARMv8 architecture reference
> +manual (ARM DDI 0487A.k) Chapter 'Part H: External debug'. The external debug
> +module is mainly used for two modes: self-hosted debug and external debug,
> and
> +it can be accessed from mmio region from Coresight and eventually the debug
> +module connects with CPU for debugging. And the debug module provides
> +sample-based profiling extension, which can be used to sample CPU program
> +counter, secure state and exception level, etc; usually every CPU has one
> +dedicated debug module to be connected.
> +
> +Required properties:
> +
> +- compatible : should be
> + * "arm,coresight-debug", "arm,primecell"; supplemented with
> + "arm,primecell" as driver is using the AMBA bus interface.
* "arm,coresight-debug"; supplemented with "arm,primecell" since
this driver is using the AMBA bus interface.
> +
> +- reg : physical base address and length of the register set.
> +
> +- clocks : the clock associated to this component.
> +
> +- clock-names : the name of the clock referenced by the code. Since we are
> + using the AMBA framework, the name of the clock providing
> + the interconnect should be "apb_pclk" and the clock is
> + mandatory. The interface between the debug logic and the
> + processor core is clocked by the internal CPU clock, so it
> + is enabled with CPU clock by default.
> +
> +- cpu : the cpu phandle the debug module is affined to. When omitted
> + the source is considered to belong to CPU0.
s/source/module
With those change:
Reviewed-by: Mathieu Poirier <mathieu.poir...@linaro.org>
> +
> +Example:
> +
> + debug@f6590000 {
> + compatible = "arm,coresight-debug","arm,primecell";
> + reg = <0 0xf6590000 0 0x1000>;
> + clocks = <&sys_ctrl HI6220_DAPB_CLK>;
> + clock-names = "apb_pclk";
> + cpu = <&cpu0>;
> + };
> --
> 2.7.4
>
