diff options
Diffstat (limited to 'Documentation/devicetree/bindings/arm')
3 files changed, 52 insertions, 85 deletions
diff --git a/Documentation/devicetree/bindings/arm/calxeda/l2ecc.yaml b/Documentation/devicetree/bindings/arm/calxeda/l2ecc.yaml index a9fe01238a88..76b65ea149b6 100644 --- a/Documentation/devicetree/bindings/arm/calxeda/l2ecc.yaml +++ b/Documentation/devicetree/bindings/arm/calxeda/l2ecc.yaml @@ -16,7 +16,7 @@ maintainers: properties: compatible: - const: "calxeda,hb-sregs-l2-ecc" + const: calxeda,hb-sregs-l2-ecc reg: maxItems: 1 diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt b/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt deleted file mode 100644 index 606b4b1b709d..000000000000 --- a/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt +++ /dev/null @@ -1,84 +0,0 @@ -QCOM Idle States for cpuidle driver - -ARM provides idle-state node to define the cpuidle states, as defined in [1]. -cpuidle-qcom is the cpuidle driver for Qualcomm SoCs and uses these idle -states. Idle states have different enter/exit latency and residency values. -The idle states supported by the QCOM SoC are defined as - - - * Standby - * Retention - * Standalone Power Collapse (Standalone PC or SPC) - * Power Collapse (PC) - -Standby: Standby does a little more in addition to architectural clock gating. -When the WFI instruction is executed the ARM core would gate its internal -clocks. In addition to gating the clocks, QCOM cpus use this instruction as a -trigger to execute the SPM state machine. The SPM state machine waits for the -interrupt to trigger the core back in to active. This triggers the cache -hierarchy to enter standby states, when all cpus are idle. An interrupt brings -the SPM state machine out of its wait, the next step is to ensure that the -cache hierarchy is also out of standby, and then the cpu is allowed to resume -execution. This state is defined as a generic ARM WFI state by the ARM cpuidle -driver and is not defined in the DT. The SPM state machine should be -configured to execute this state by default and after executing every other -state below. - -Retention: Retention is a low power state where the core is clock gated and -the memory and the registers associated with the core are retained. The -voltage may be reduced to the minimum value needed to keep the processor -registers active. The SPM should be configured to execute the retention -sequence and would wait for interrupt, before restoring the cpu to execution -state. Retention may have a slightly higher latency than Standby. - -Standalone PC: A cpu can power down and warmboot if there is a sufficient time -between the time it enters idle and the next known wake up. SPC mode is used -to indicate a core entering a power down state without consulting any other -cpu or the system resources. This helps save power only on that core. The SPM -sequence for this idle state is programmed to power down the supply to the -core, wait for the interrupt, restore power to the core, and ensure the -system state including cache hierarchy is ready before allowing core to -resume. Applying power and resetting the core causes the core to warmboot -back into Elevation Level (EL) which trampolines the control back to the -kernel. Entering a power down state for the cpu, needs to be done by trapping -into a EL. Failing to do so, would result in a crash enforced by the warm boot -code in the EL for the SoC. On SoCs with write-back L1 cache, the cache has to -be flushed in s/w, before powering down the core. - -Power Collapse: This state is similar to the SPC mode, but distinguishes -itself in that the cpu acknowledges and permits the SoC to enter deeper sleep -modes. In a hierarchical power domain SoC, this means L2 and other caches can -be flushed, system bus, clocks - lowered, and SoC main XO clock gated and -voltages reduced, provided all cpus enter this state. Since the span of low -power modes possible at this state is vast, the exit latency and the residency -of this low power mode would be considered high even though at a cpu level, -this essentially is cpu power down. The SPM in this state also may handshake -with the Resource power manager (RPM) processor in the SoC to indicate a -complete application processor subsystem shut down. - -The idle-state for QCOM SoCs are distinguished by the compatible property of -the idle-states device node. - -The devicetree representation of the idle state should be - - -Required properties: - -- compatible: Must be one of - - "qcom,idle-state-ret", - "qcom,idle-state-spc", - "qcom,idle-state-pc", - and "arm,idle-state". - -Other required and optional properties are specified in [1]. - -Example: - - idle-states { - CPU_SPC: spc { - compatible = "qcom,idle-state-spc", "arm,idle-state"; - entry-latency-us = <150>; - exit-latency-us = <200>; - min-residency-us = <2000>; - }; - }; - -[1]. Documentation/devicetree/bindings/cpu/idle-states.yaml diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-remote-etm.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-remote-etm.yaml new file mode 100644 index 000000000000..4fd5752978cd --- /dev/null +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-remote-etm.yaml @@ -0,0 +1,51 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/arm/qcom,coresight-remote-etm.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Qualcomm Coresight Remote ETM(Embedded Trace Macrocell) + +maintainers: + - Jinlong Mao <quic_jinlmao@quicinc.com> + - Tao Zhang <quic_taozha@quicinc.com> + +description: + Support for ETM trace collection on remote processor using coresight + framework. Enabling this will allow turning on ETM tracing on remote + processor like modem processor via sysfs and collecting the trace + via coresight TMC sinks. + +properties: + compatible: + const: qcom,coresight-remote-etm + + out-ports: + $ref: /schemas/graph.yaml#/properties/ports + additionalProperties: false + + properties: + port: + description: Output connection to the CoreSight Trace bus. + $ref: /schemas/graph.yaml#/properties/port + +required: + - compatible + - out-ports + +additionalProperties: false + +examples: + - | + etm { + compatible = "qcom,coresight-remote-etm"; + + out-ports { + port { + modem_etm0_out_funnel_modem: endpoint { + remote-endpoint = <&funnel_modem_in_modem_etm0>; + }; + }; + }; + }; +... |