NVIDIA Tegra Power Management Controller (PMC) == Power Management Controller Node == The PMC block interacts with an external Power Management Unit. The PMC mostly controls the entry and exit of the system from different sleep modes. It provides power-gating controllers for SoC and CPU power-islands. Required properties: - name : Should be pmc - compatible : Should contain one of the following: For Tegra20 must contain "nvidia,tegra20-pmc". For Tegra30 must contain "nvidia,tegra30-pmc". For Tegra114 must contain "nvidia,tegra114-pmc" For Tegra124 must contain "nvidia,tegra124-pmc" For Tegra132 must contain "nvidia,tegra124-pmc" For Tegra210 must contain "nvidia,tegra210-pmc" - reg : Offset and length of the register set for the device - clocks : Must contain an entry for each entry in clock-names. See ../clocks/clock-bindings.txt for details. - clock-names : Must include the following entries: "pclk" (The Tegra clock of that name), "clk32k_in" (The 32KHz clock input to Tegra). Optional properties: - nvidia,invert-interrupt : If present, inverts the PMU interrupt signal. The PMU is an external Power Management Unit, whose interrupt output signal is fed into the PMC. This signal is optionally inverted, and then fed into the ARM GIC. The PMC is not involved in the detection or handling of this interrupt signal, merely its inversion. - nvidia,suspend-mode : The suspend mode that the platform should use. Valid values are 0, 1 and 2: 0 (LP0): CPU + Core voltage off and DRAM in self-refresh 1 (LP1): CPU voltage off and DRAM in self-refresh 2 (LP2): CPU voltage off - nvidia,core-power-req-active-high : Boolean, core power request active-high - nvidia,sys-clock-req-active-high : Boolean, system clock request active-high - nvidia,combined-power-req : Boolean, combined power request for CPU & Core - nvidia,cpu-pwr-good-en : Boolean, CPU power good signal (from PMIC to PMC) is enabled. Required properties when nvidia,suspend-mode is specified: - nvidia,cpu-pwr-good-time : CPU power good time in uS. - nvidia,cpu-pwr-off-time : CPU power off time in uS. - nvidia,core-pwr-good-time : Core power good time in uS. - nvidia,core-pwr-off-time : Core power off time in uS. Required properties when nvidia,suspend-mode=<0>: - nvidia,lp0-vec : Starting address and length of LP0 vector The LP0 vector contains the warm boot code that is executed by AVP when resuming from the LP0 state. The AVP (Audio-Video Processor) is an ARM7 processor and always being the first boot processor when chip is power on or resume from deep sleep mode. When the system is resumed from the deep sleep mode, the warm boot code will restore some PLLs, clocks and then bring up CPU0 for resuming the system. Hardware-triggered thermal reset: On Tegra30, Tegra114 and Tegra124, if the 'i2c-thermtrip' subnode exists, hardware-triggered thermal reset will be enabled. Required properties for hardware-triggered thermal reset (inside 'i2c-thermtrip'): - nvidia,i2c-controller-id : ID of I2C controller to send poweroff command to. Valid values are described in section 9.2.148 "APBDEV_PMC_SCRATCH53_0" of the Tegra K1 Technical Reference Manual. - nvidia,bus-addr : Bus address of the PMU on the I2C bus - nvidia,reg-addr : I2C register address to write poweroff command to - nvidia,reg-data : Poweroff command to write to PMU Optional properties for hardware-triggered thermal reset (inside 'i2c-thermtrip'): - nvidia,pinmux-id : Pinmux used by the hardware when issuing poweroff command. Defaults to 0. Valid values are described in section 12.5.2 "Pinmux Support" of the Tegra4 Technical Reference Manual. Optional nodes: - powergates : This node contains a hierarchy of power domain nodes, which should match the powergates on the Tegra SoC. See "Powergate Nodes" below. Example: / SoC dts including file pmc@7000f400 { compatible = "nvidia,tegra20-pmc"; reg = <0x7000e400 0x400>; clocks = <&tegra_car 110>, <&clk32k_in>; clock-names = "pclk", "clk32k_in"; nvidia,invert-interrupt; nvidia,suspend-mode = <1>; nvidia,cpu-pwr-good-time = <2000>; nvidia,cpu-pwr-off-time = <100>; nvidia,core-pwr-good-time = <3845 3845>; nvidia,core-pwr-off-time = <458>; nvidia,core-power-req-active-high; nvidia,sys-clock-req-active-high; nvidia,lp0-vec = <0xbdffd000 0x2000>; }; / Tegra board dts file { ... pmc@7000f400 { i2c-thermtrip { nvidia,i2c-controller-id = <4>; nvidia,bus-addr = <0x40>; nvidia,reg-addr = <0x36>; nvidia,reg-data = <0x2>; }; }; ... clocks { compatible = "simple-bus"; #address-cells = <1>; #size-cells = <0>; clk32k_in: clock { compatible = "fixed-clock"; reg=<0>; #clock-cells = <0>; clock-frequency = <32768>; }; }; ... }; == Powergate Nodes == Each of the powergate nodes represents a power-domain on the Tegra SoC that can be power-gated by the Tegra PMC. The name of the powergate node should be one of the below. Note that not every powergate is applicable to all Tegra devices and the following list shows which powergates are applicable to which devices. Please refer to the Tegra TRM for more details on the various powergates. Name Description Devices Applicable 3d 3D Graphics Tegra20/114/124/210 3d0 3D Graphics 0 Tegra30 3d1 3D Graphics 1 Tegra30 aud Audio Tegra210 dfd Debug Tegra210 dis Display A Tegra114/124/210 disb Display B Tegra114/124/210 heg 2D Graphics Tegra30/114/124/210 iram Internal RAM Tegra124/210 mpe MPEG Encode All nvdec NVIDIA Video Decode Engine Tegra210 nvjpg NVIDIA JPEG Engine Tegra210 pcie PCIE Tegra20/30/124/210 sata SATA Tegra30/124/210 sor Display interfaces Tegra124/210 ve2 Video Encode Engine 2 Tegra210 venc Video Encode Engine All vdec Video Decode Engine Tegra20/30/114/124 vic Video Imaging Compositor Tegra124/210 xusba USB Partition A Tegra114/124/210 xusbb USB Partition B Tegra114/124/210 xusbc USB Partition C Tegra114/124/210 Required properties: - clocks: Must contain an entry for each clock required by the PMC for controlling a power-gate. See ../clocks/clock-bindings.txt for details. - resets: Must contain an entry for each reset required by the PMC for controlling a power-gate. See ../reset/reset.txt for details. - #power-domain-cells: Must be 0. Example: pmc: pmc@7000e400 { compatible = "nvidia,tegra210-pmc"; reg = <0x0 0x7000e400 0x0 0x400>; clocks = <&tegra_car TEGRA210_CLK_PCLK>, <&clk32k_in>; clock-names = "pclk", "clk32k_in"; powergates { pd_audio: aud { clocks = <&tegra_car TEGRA210_CLK_APE>, <&tegra_car TEGRA210_CLK_APB2APE>; resets = <&tegra_car 198>; #power-domain-cells = <0>; }; }; }; == Powergate Clients == Hardware blocks belonging to a power domain should contain a "power-domains" property that is a phandle pointing to the corresponding powergate node. Example: adma: adma@702e2000 { ... power-domains = <&pd_audio>; ... }; == Pad Control == On Tegra SoCs a pad is a set of pins which are configured as a group. The pin grouping is a fixed attribute of the hardware. The PMC can be used to set pad power state and signaling voltage. A pad can be either in active or power down mode. The support for power state and signaling voltage configuration varies depending on the pad in question. 3.3 V and 1.8 V signaling voltages are supported on pins where software controllable signaling voltage switching is available. The pad configuration state nodes are placed under the pmc node and they are referred to by the pinctrl client properties. For more information see Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt. The pad name should be used as the value of the pins property in pin configuration nodes. The following pads are present on Tegra124 and Tegra132: audio bb cam comp csia csb cse dsi dsib dsic dsid hdmi hsic hv lvds mipi-bias nand pex-bias pex-clk1 pex-clk2 pex-cntrl sdmmc1 sdmmc3 sdmmc4 sys_ddc uart usb0 usb1 usb2 usb_bias The following pads are present on Tegra210: audio audio-hv cam csia csib csic csid csie csif dbg debug-nonao dmic dp dsi dsib dsic dsid emmc emmc2 gpio hdmi hsic lvds mipi-bias pex-bias pex-clk1 pex-clk2 pex-cntrl sdmmc1 sdmmc3 spi spi-hv uart usb0 usb1 usb2 usb3 usb-bias Required pin configuration properties: - pins: Must contain name of the pad(s) to be configured. Optional pin configuration properties: - low-power-enable: Configure the pad into power down mode - low-power-disable: Configure the pad into active mode - power-source: Must contain either TEGRA_IO_PAD_VOLTAGE_1V8 or TEGRA_IO_PAD_VOLTAGE_3V3 to select between signaling voltages. The values are defined in include/dt-bindings/pinctrl/pinctrl-tegra-io-pad.h. Note: The power state can be configured on all of the Tegra124 and Tegra132 pads. None of the Tegra124 or Tegra132 pads support signaling voltage switching. Note: All of the listed Tegra210 pads except pex-cntrl support power state configuration. Signaling voltage switching is supported on following Tegra210 pads: audio, audio-hv, cam, dbg, dmic, gpio, pex-cntrl, sdmmc1, sdmmc3, spi, spi-hv, and uart. Pad configuration state example: pmc: pmc@7000e400 { compatible = "nvidia,tegra210-pmc"; reg = <0x0 0x7000e400 0x0 0x400>; clocks = <&tegra_car TEGRA210_CLK_PCLK>, <&clk32k_in>; clock-names = "pclk", "clk32k_in"; ... sdmmc1_3v3: sdmmc1-3v3 { pins = "sdmmc1"; power-source = ; }; sdmmc1_1v8: sdmmc1-1v8 { pins = "sdmmc1"; power-source = ; }; hdmi_off: hdmi-off { pins = "hdmi"; low-power-enable; } hdmi_on: hdmi-on { pins = "hdmi"; low-power-disable; } }; Pinctrl client example: sdmmc1: sdhci@700b0000 { ... pinctrl-names = "sdmmc-3v3", "sdmmc-1v8"; pinctrl-0 = <&sdmmc1_3v3>; pinctrl-1 = <&sdmmc1_1v8>; }; ... sor@54540000 { ... pinctrl-0 = <&hdmi_off>; pinctrl-1 = <&hdmi_on>; pinctrl-names = "hdmi-on", "hdmi-off"; };