diff options
Diffstat (limited to 'Documentation/devicetree/bindings/arm')
6 files changed, 253 insertions, 9 deletions
diff --git a/Documentation/devicetree/bindings/arm/msm/ids.txt b/Documentation/devicetree/bindings/arm/msm/ids.txt new file mode 100644 index 000000000000..9ee8428f4670 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/msm/ids.txt @@ -0,0 +1,65 @@ +* MSM-ID + +The qcom,msm-id entry specifies the MSM chipset and hardware revision. It can +optionally be an array of these to indicate multiple hardware that use the same +device tree. It is expected that the bootloader will use this information at +boot-up to decide which device tree to use when given multiple device trees, +some of which may not be compatible with the actual hardware. It is the +bootloader's responsibility to pass the correct device tree to the kernel. + +PROPERTIES + +- qcom,msm-id: + Usage: required + Value type: <prop-encoded-array> (<chipset_id, rev_id> [, <c2, r2> ..]) + Definition: + The "chipset_id" consists of three fields as below: + + bits 0-15 = The unique MSM chipset id. + bits 16-31 = Reserved. Should be 0 + + chipset_id is an exact match value + + The "rev_id" is a chipset specific 32-bit id that represents + the version of the chipset. + + The rev_id is a best match id. The bootloader will look for + the closest possible patch. + +* BOARD-ID + +The qcom,board-id entry specifies the board type and revision information. It +can optionally be an array of these to indicate multiple boards that use the +same device tree. It is expected that the bootloader will use this information +at boot-up to decide which device tree to use when given multiple device trees, +some of which may not be compatible with the actual hardware. It is the +bootloader's responsibility to pass the correct device tree to the kernel. + +PROPERTIES + +- qcom,board-id: + Usage: required + Value type: <prop-encoded-array> (<board_id, subtype_id> [, <b2, s2> ..]) + Definition: + The "board_id" consists of three fields as below: + + bits 31-24 = Unusued. + bits 23-16 = Platform Version Major + bits 15-8 = Platfrom Version Minor + bits 7-0 = Platform Type + + Platform Type field is an exact match value. The Platform + Major/Minor field is a best match. The bootloader will look + for the closest possible match. + + The "subtype_id" is unique to a Platform Type/Chipset ID. For + a given Platform Type, there will typically only be a single + board and the subtype_id will be 0. However in some cases board + variants may need to be distinquished by different subtype_id + values. + + subtype_id is an exact match value. + +EXAMPLE: + qcom,board-id = <15 2>; + qcom,msm-id = <0x1007e 0>; diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt b/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt new file mode 100644 index 000000000000..06df04cc827a --- /dev/null +++ b/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt @@ -0,0 +1,84 @@ +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/arm/idle-states.txt diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt index 1333db9acfee..382a574a5c55 100644 --- a/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt +++ b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt @@ -21,10 +21,17 @@ PROPERTIES the register region. An optional second element specifies the base address and size of the alias register region. +- clock-output-names: + Usage: optional + Value type: <string> + Definition: Name of the output clock. Typically acpuX_aux where X is a + CPU number starting at 0. + Example: clock-controller@2088000 { compatible = "qcom,kpss-acc-v2"; reg = <0x02088000 0x1000>, <0x02008000 0x1000>; + clock-output-names = "acpu0_aux"; }; diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,kpss-gcc.txt b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-gcc.txt new file mode 100644 index 000000000000..d1e12f16a28c --- /dev/null +++ b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-gcc.txt @@ -0,0 +1,28 @@ +Krait Processor Sub-system (KPSS) Global Clock Controller (GCC) + +PROPERTIES + +- compatible: + Usage: required + Value type: <string> + Definition: should be one of: + "qcom,kpss-gcc" + +- reg: + Usage: required + Value type: <prop-encoded-array> + Definition: base address and size of the register region + +- clock-output-names: + Usage: required + Value type: <string> + Definition: Name of the output clock. Typically acpu_l2_aux indicating + an L2 cache auxiliary clock. + +Example: + + l2cc: clock-controller@2011000 { + compatible = "qcom,kpss-gcc"; + reg = <0x2011000 0x1000>; + clock-output-names = "acpu_l2_aux"; + }; diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,pvs.txt b/Documentation/devicetree/bindings/arm/msm/qcom,pvs.txt new file mode 100644 index 000000000000..e7cb10426a3b --- /dev/null +++ b/Documentation/devicetree/bindings/arm/msm/qcom,pvs.txt @@ -0,0 +1,38 @@ +Qualcomm Process Voltage Scaling Tables + +The node name is required to be "qcom,pvs". There shall only be one +such node present in the root of the tree. + +PROPERTIES + +- qcom,pvs-format-a or qcom,pvs-format-b: + Usage: required + Value type: <empty> + Definition: Indicates the format of qcom,speedX-pvsY-bin-vZ properties. + If qcom,pvs-format-a is used the table is two columns + (frequency and voltage in that order). If qcom,pvs-format-b is used the table is three columns (frequency, voltage, + and current in that order). + +- qcom,speedX-pvsY-bin-vZ: + Usage: required + Value type: <prop-encoded-array> + Definition: The PVS table corresponding to the speed bin X, pvs bin Y, + and version Z. +Example: + + qcom,pvs { + qcom,pvs-format-a; + qcom,speed0-pvs0-bin-v0 = + < 384000000 950000 >, + < 486000000 975000 >, + < 594000000 1000000 >, + < 702000000 1025000 >, + < 810000000 1075000 >, + < 918000000 1100000 >, + < 1026000000 1125000 >, + < 1134000000 1175000 >, + < 1242000000 1200000 >, + < 1350000000 1225000 >, + < 1458000000 1237500 >, + < 1512000000 1250000 >; + }; diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,saw2.txt b/Documentation/devicetree/bindings/arm/msm/qcom,saw2.txt index 1505fb8e131a..ae4afc6dcfe0 100644 --- a/Documentation/devicetree/bindings/arm/msm/qcom,saw2.txt +++ b/Documentation/devicetree/bindings/arm/msm/qcom,saw2.txt @@ -2,22 +2,31 @@ SPM AVS Wrapper 2 (SAW2) The SAW2 is a wrapper around the Subsystem Power Manager (SPM) and the Adaptive Voltage Scaling (AVS) hardware. The SPM is a programmable -micro-controller that transitions a piece of hardware (like a processor or +power-controller that transitions a piece of hardware (like a processor or subsystem) into and out of low power modes via a direct connection to the PMIC. It can also be wired up to interact with other processors in the system, notifying them when a low power state is entered or exited. +Multiple revisions of the SAW hardware are supported using these Device Nodes. +SAW2 revisions differ in the register offset and configuration data. Also, the +same revision of the SAW in different SoCs may have different configuration +data due the the differences in hardware capabilities. Hence the SoC name, the +version of the SAW hardware in that SoC and the distinction between cpu (big +or Little) or cache, may be needed to uniquely identify the SAW register +configuration and initialization data. The compatible string is used to +indicate this parameter. + PROPERTIES - compatible: Usage: required Value type: <string> - Definition: shall contain "qcom,saw2". A more specific value should be - one of: - "qcom,saw2-v1" - "qcom,saw2-v1.1" - "qcom,saw2-v2" - "qcom,saw2-v2.1" + Definition: Must have + "qcom,saw2" + A more specific value could be one of: + "qcom,apq8064-saw2-v1.1-cpu" + "qcom,msm8974-saw2-v2.1-cpu" + "qcom,apq8084-saw2-v2.1-cpu" - reg: Usage: required @@ -26,10 +35,23 @@ PROPERTIES the register region. An optional second element specifies the base address and size of the alias register region. +- regulator: + Usage: optional + Value type: boolean + Definition: Indicates that this SPM device acts as a regulator device + device for the core (CPU or Cache) the SPM is attached + to. -Example: +Example 1: - regulator@2099000 { + power-controller@2099000 { compatible = "qcom,saw2"; reg = <0x02099000 0x1000>, <0x02009000 0x1000>; + regulator; + }; + +Example 2: + saw0: power-controller@f9089000 { + compatible = "qcom,apq8084-saw2-v2.1-cpu", "qcom,saw2"; + reg = <0xf9089000 0x1000>, <0xf9009000 0x1000>; }; |