From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934771AbdDFNcJ (ORCPT ); Thu, 6 Apr 2017 09:32:09 -0400 Received: from mail-pg0-f51.google.com ([74.125.83.51]:35285 "EHLO mail-pg0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934750AbdDFNcA (ORCPT ); Thu, 6 Apr 2017 09:32:00 -0400 From: Leo Yan To: Jonathan Corbet , Rob Herring , Mark Rutland , Wei Xu , Catalin Marinas , Will Deacon , Andy Gross , David Brown , Mathieu Poirier , Suzuki K Poulose , Stephen Boyd , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, Mike Leach , Sudeep Holla Cc: Leo Yan Subject: [PATCH v6 1/8] coresight: bindings for CPU debug module Date: Thu, 6 Apr 2017 21:30:54 +0800 Message-Id: <1491485461-22800-2-git-send-email-leo.yan@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1491485461-22800-1-git-send-email-leo.yan@linaro.org> References: <1491485461-22800-1-git-send-email-leo.yan@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Reviewed-by: Mathieu Poirier Reviewed-by: Suzuki K Poulose Acked-by: Rob Herring Signed-off-by: Leo Yan --- .../bindings/arm/coresight-cpu-debug.txt | 49 ++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 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 0000000..2982912 --- /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>; + }; -- 2.7.4