From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- .../bindings/arm/coresight-cpu-debug.txt | 49 ++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt (limited to 'Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt') diff --git a/Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt b/Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt new file mode 100644 index 000000000..298291211 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt @@ -0,0 +1,49 @@ +* CoreSight CPU Debug Component: + +CoreSight CPU 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-cpu-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 module is considered to belong to CPU0. + +Optional properties: + +- power-domains: a phandle to the debug power domain. We use "power-domains" + binding to turn on the debug logic if it has own dedicated + power domain and if necessary to use "cpuidle.off=1" or + "nohlt" in the kernel command line or sysfs node to + constrain idle states to ensure registers in the CPU power + domain are accessible. + +Example: + + debug@f6590000 { + compatible = "arm,coresight-cpu-debug","arm,primecell"; + reg = <0 0xf6590000 0 0x1000>; + clocks = <&sys_ctrl HI6220_DAPB_CLK>; + clock-names = "apb_pclk"; + cpu = <&cpu0>; + }; -- cgit v1.2.3