K230 PMU User Guide

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Directory

[TOC]

preface

Overview

This document describes the specific usage methods of PMU modules and SDK configuration compilation methods, including the construction of software and hardware environments, and introduces the control interface.

Reader object

This document (this guide) is intended primarily for:

• Technical Support Engineer
• Software Development Engineer

Definition of acronyms

Revision history

1. Function introduction

The PMU module provides 6 input and 2 output ports, each with the following functions:

1. INT0 is used as the power on and off button by default, supporting long press to power on, long press shutdown event reporting, long press forced shutdown, level or edge event reporting, support debounce, two long press times can be matched
2. INT1 supports level or edge detection, edge count detection, both support triggering boot and reporting events, support debounce, and edge count values can be configured (it is recommended not to open both detection modes at the same time, the edge detection function will be overridden)
3. INT2 supports level or edge detection, triggers power-on and report events, and debounces
4. INT3 supports level or edge detection, triggers power-on and escalation events, and debounces
5. INT4 supports level or edge detection, triggering power-on and reporting events (edge detection recommended)
6. INT5 supports level or edge detection, triggering power-on and reporting events (edge detection recommended)
7. OUTPUT0 is used to control PMICs
8. OUTPUT1 not used yet

The PMU module also provides a log storage function of 64Byte, of which the last 4Byte is used by the driver and the remaining 60Byte is left to the user

2. User Control

The PMU can be controlled by the user through the device tree and sysfs, the PMU can be configured through the device tree at system startup, and the PMU can be dynamically configured through sysfs after startup

2.1 PMU Device Tree Configuration

pmu: pmu@0x91000000 {
    compatible = "kendryte, k230-pmu";
    reg = <0x0 0x91000000 0x0 0xb0>;
    interrupt-parent = <&intc>;
    interrupts = <175>;
    status = "disabled";
    /*
    int0 {
        force-powerdown-value = <320000>;
        power-event-value = <96000>;
        debounce-value = <256>;
        type = <IRQ_TYPE_EDGE_RISING>;
        wakeup;
        event;
    };
    int1 {
        debounce-value = <256>;
        edge-cnt-type = <IRQ_TYPE_EDGE_RISING>;
        edge-cnt-value = <1>;
        edge-cnt-wakeup;
        edge-cnt-event;
        type = <IRQ_TYPE_EDGE_RISING>;
        wakeup;
        event;
    };
    int2 {
        debounce-value = <256>;
        type = <IRQ_TYPE_EDGE_RISING>;
        wakeup;
        event;
    };
    int3 {
        debounce-value = <256>;
        type = <IRQ_TYPE_EDGE_RISING>;
        wakeup;
        event;
    };
    int4 {
        type = <IRQ_TYPE_EDGE_FALLING>;
        wakeup;
        event;
    };
    int5 {
        type = <IRQ_TYPE_EDGE_RISING>;
        wakeup;
        event;
    };
    rtc {
        alarm-wakeup;
        alarm-event;
        tick-wakeup;
        tick-event;
    };
    */
};

Key field meanings:

• force-powerdown-value Long press to force shutdown time
• power-event-value Long press on and long press on the shutdown event time
• debounce-value Debounce time
• type Detection type, support rising edge, falling edge, high level, low level
• wakeup Enable power-on to wake up red energy
• event Enable event reporting
• edge-cnt-type Detection type, support rising edge, falling edge
• edge-cnt-value Edge count value

All times are measured in (1/32768) seconds, e.g. 327680 for 10 seconds

2.2 PMU file control

PMU sysfs is located in /sys/devices/platform/soc/91000000.pmuthe directory and the file structure is as follows:

.
|-- driver -> ../../../../bus/platform/drivers/k230-pmu
|-- driver_override
|-- int0
|   |-- debounce_value
|   |-- event
|   |-- force_powerdown_value
|   |-- power_event_value
|   |-- type
|   `-- wakeup
|-- int1
|   |-- debounce_value
|   |-- edge_cnt_event
|   |-- edge_cnt_type
|   |-- edge_cnt_value
|   |-- edge_cnt_wakeup
|   |-- event
|   |-- type
|   `-- wakeup
|-- int2
|   |-- debounce_value
|   |-- event
|   |-- type
|   `-- wakeup
|-- int3
|   |-- debounce_value
|   |-- event
|   |-- type
|   `-- wakeup
|-- int4
|   |-- event
|   |-- type
|   `-- wakeup
|-- int5
|   |-- event
|   |-- type
|   `-- wakeup
|-- modalias
|-- of_node -> ../../../../firmware/devicetree/base/soc/pmu@0x91000000
|-- pmu
|   |-- pmu_logs
|   |-- pmu_regs
|   |-- pmu_status
|   `-- wakeup_source
|-- rtc
|   |-- alarm_event
|   |-- alarm_wakeup
|   |-- tick_event
|   `-- tick_wakeup
|-- subsystem -> ../../../../bus/platform
`-- uevent

Main file features:

• pmu/pmu_status PMU Status (read-only)
  • PMU_RESET The PMU is powered off
  • SOC_FORCE_PD The SoC is forced to power down
  • SOC_NORMAL_PD The SoC is powered off normally
  • SOC_RESET The SoC is reset
• pmu/wakeup_source system wakeup source (read-only) INT0,INT1,INT2,INT3,INT4,INT5,RTC_ALARM,RTC_TICK
• pmu/pmu_logs User LOG file (binary file, 4-byte alignment required for read and write)
• pmu/pmu_regs PMU debugging (binary, 4-byte alignment required for read and write)
• int0/force_powerdown_value Long press to force shutdown time
• int0/power_event_value Long press on and long press on the shutdown event time
• int1/edge_cnt_type Detection type, valid values "rising", "falling"
• int1/edge_cnt_value Edge count value
• */debounce_value Debounce time
• */type Detection type, valid values "rising", "falling", "low", "high"
• */*wakeup Wake up, valid values "enabled", "disabled"
• */*event Event reported, valid values "enabled", "disabled"

For example, enable INT1 rising edge to wake up:

cd /sys/devices/platform/soc/91000000.pmu/int1
echo rising > type
echo enabled > wakeup

For example, enable INT2 falling edge events to be reported:

cd /sys/devices/platform/soc/91000000.pmu/int2
echo falling > type
echo enabled > event

2.3 PMU events are reported

PMU uses the input subsystem to report events, and the reported event code is so EV_KEYthat users can perform business processing after receiving the corresponding events. For example, after receivingKEY_POWER the key value, the user can perform shutdown preparation and invoke thepoweroff shutdown command

You can use the evtesttool for testing with the following event table:

2.4 PMU shutdown control

1. Use poweroffthe command shutdown
2. Force shutdown by pressing the INT0 button long (not recommended unless the system is down. Forced shutdown after system downtime will cause PMU to wake up).

3. Hardware connection

When using a PMU, you need to set up the EVB board as follows

1. Use the jumper cap to connect PIN13(OUT0) and PIN14(PW_EN) of the J1 interface, taking care to disconnect PIN15(SYS_SW) and PIN16(PW_EN)
2. Depending on the different wake-up source, PIN2 (SYS_ON_OFF) is connected to the corresponding PIN using a jumper, and the button K1 can control the state of INT, press the button to go high, and release it to low

   Wake source	PIN	label
   INT0	1	INT0
   INT1	3	INT1
   INT2	5	INT2
   INT3	7	INT3
   INT4	9	INT4
   INT5	11	INT5

Connection diagram using INT0 as a wake-up source:

4. Precautions

1. The PMU module is not enabled by default in the device tree, if you need to use it, enable it in the device tree
2. When using the PMU module, be sure to wake up the PMU module through any INT, otherwise the kernel will be stuck when initializing the driver