Complete Rockchip RK809 PMIC Guide: Pins, Sequencing, DTS, Power and Debugging

Chinese source V1.0.0, kernel scope 4.4 / 4.19. The technical preface introduces RK809 submodule concepts, functions, DTS configuration and troubleshooting; the full technical body is retained. No English PDF is available. All four languages use Chinese-PDF original figures, some already bearing English labels. Platform reference only: verify the actual ArmSoM PMIC, SoC, power tree, pins, SDK/BSP and kernel. Not a claim of support on every ArmSoM board; no hardware testing was performed.

Voltage, pin-mode and register writes can power off or damage hardware; these are unexecuted source examples. Source 0.737.5, differences between voltage/sequence tables, regulator-ramp-delay 12500 versus example 6001, and the claimed four functions versus actual list count are retained without guessing corrections. Verify the source shutdown location “PCIE”, rockchi path and DCDC3 external-divider-only claim versus internal voltage settings in the sequence table against the BSP. Source headings 3.1/3.2 only say “kernel”; no version was invented.

ArmSoM Docs · Rockchip kernel

1. Basics

1.1 Overview

RK809 is a high-performance PMIC integrating 5 high-current DCDCs, 9 LDOs, 2 SWITCH outputs, 1 RTC, 1 high-performance CODEC and adjustable power-up sequencing. System supplies are divided into DCDC and LDO types, with the following general characteristics; consult further references for details.

1. DCDC: efficient at a large input/output voltage difference, but with relatively high ripple and cost; therefore used for large voltage drops and high-current loads. Two common modes are PWM, with good ripple/transient response but lower efficiency, and PFM, with higher efficiency but weaker load capability.

2. LDO: low efficiency at a large input/output voltage difference, but low cost. Optimize the system to improve conversion efficiency: for a 1.1V LDO output, its input can be supplied by the VCCIO_3.3V DCDC. Where the circuit permits, connect the LDO input to a DCDC output, taking power-up sequencing into account.

1.2 Functions

From the user perspective, RK809 functions are described as four parts:

1. regulator: controls the state of individual DCDC and LDO supplies.

2. rtc: provides clockkeeping, timing and related functions.

3. gpio: ordinary GPIO operation with pinctrl functionality.

4. pwrkey: detects power-key press/release, saving one AP GPIO.

5. clk: two 32.768KHZ clock outputs; one is always on and cannot be controlled, while the other is software-controlled.

6. codec: sampling up to 192KHZ, 16bit and 32bit, DAC, ADC, PDM and other functions. Not covered here; the source states that a dedicated document will explain it later.

1.3 Pin functions

Chinese PDF original · p6

Pay particular attention to SLEEP and INT; the sleep pin also provides extended GPIO functionality.

Chinese PDF original · p7

Chinese PDF original · p7

Chinese PDF original · p8

Editable transcription of the original tables above.

1.4 Important concepts

I2C address: 7-bit slave address 0x20. The PMIC has three operating modes.

1. PMIC normal mode: during normal system operation the PMIC is in normal mode and pmic_sleep is low.

2. PMIC sleep mode reduces PMIC consumption during system suspend. Depending on product requirements, some rail voltages are lowered or outputs disabled. During standby the AP configures pmic_sleep as sleep over I2C and raises it to enter sleep. When the SoC wakes, pmic_sleep returns low and the PMIC exits sleep.

3. PMIC shutdown mode: the PMIC powers down the whole system. The AP configures pmic_sleep as shutdown over I2C and raises the pin. Normally pmic_sleep is low for normal mode; high switches to sleep or shutdown. On RK809 this pin is multiplexed, with the required function selected using pinctrl:

4. SLEEP: switch SLEEP mode.

5. Power-off: POWER DOWN.

6. Reset: RESET.

7. Idle: no function.

pmic_int: normally high; an interrupt drives it low, and it stays low until the interrupt is handled.

pmic_pwron: connect the hardware power key to this pin; the driver detects press/release through it.

DCDC modes: besides PWM (force PWM) and PFM, AUTO dynamically switches between PWM and PFM. The PMIC supports PWM and AUTO PWM/PFM. AUTO has higher efficiency but poorer ripple/transient response. For stability, use PWM during operation and switch to AUTO PWM/PFM during suspend.

DCDC3 voltage: this special rail cannot change voltage through registers; external divider resistors set it. Change the external hardware to change voltage. Rockchip designs generally use it for VCC_DDR.

Runtime voltage adjustment ranges of DCDC and LDO:

1. Discontinuous DCDC voltage ranges:

1. Continuous LDO voltages:

1.5 Power-on conditions and sequence

1. Power-on conditions: any one of the following powers on the PMIC:

• EN transitions from low to high.
• EN remains high and an RTC alarm interrupt occurs.
• EN remains high and the PWRON key is pressed.
• EN remains high and a charger is inserted.

1. Power-up sequencing: SoC platforms can require different rail sequences. The current sequences are shown below; consult the latest applicable datasheet for specifics.

Chinese PDF original · p10

Chinese PDF original · p10

Sequence table transcribed from the original image; blanks, x, OTP and ON/OFF are retained.

2. Configuration

2.1 Drivers and menuconfig

Kernel 4.4 configuration. RK809 driver files share some components with rk817 and rk805:

drivers/mfd/rk808.c
drivers/input/misc/rk8xx-pwrkey.c
drivers/rtc/rtc-rk808.c
drivers/gpio/gpio-rk8xx.c
drivers/regulator/rk808-regulator.c
drivers/clk/clk-rk808.c

Reference RK809 DTS file:

arch/arm64/boot/dts/rockchi/px30-evb-ddr4-v10.dts

Corresponding menuconfig symbols:

CONFIG_MFD_RK808
CONFIG_RTC_RK808
CONFIG_GPIO_RK8XX
CONFIG_REGULATOR_RK818
CONFIG_INPUT_RK8XX_PWRKEY
CONFIG_COMMON_CLK_RK808

Kernel 4.19 configuration. RK809 driver files:

drivers/mfd/rk808.c
drivers/input/misc/rk805-pwrkey.c       // 跟4.4内核不同
drivers/rtc/rtc-rk808.c
drivers/pinctrl/pinctrl-rk805.c         // 跟4.4内核不同
drivers/regulator/rk808-regulator.c     // 跟4.4内核不同
drivers/clk/clk-rk808.c

Reference RK809 DTS file:

arch/arm64/boot/dts/rockchi/px30-evb-ddr4-v10.dts

Corresponding menuconfig symbols:

CONFIG_MFD_RK808
CONFIG_RTC_RK808
CONFIG_PINCTRL_RK805
CONFIG_REGULATOR_RK808
CONFIG_INPUT_RK805_PWRKEY
CONFIG_COMMON_CLK_RK808

2.2 DTS configuration

Kernel 4.4 DTS configuration: i2c attachment, main properties, rtc, pwrkey, gpio and regulator.

&pinctrl {
    pmic {
        pmic_int: pmic_int {
            rockchip,pins =
                <0 RK_PA7 RK_FUNC_GPIO &pcfg_pull_up>;
        };
        soc_slppin_gpio: soc_slppin_gpio {
            rockchip,pins =
                <0 RK_PA4 RK_FUNC_GPIO &pcfg_output_low>;
        };
        soc_slppin_slp: soc_slppin_slp {
            rockchip,pins =
                <0 RK_PA4 RK_FUNC_1 &pcfg_pull_none>;
        };
        soc_slppin_rst: soc_slppin_rst {
            rockchip,pins =
                <0 RK_PA4 RK_FUNC_2 &pcfg_pull_none>;
        };
    };
};
&i2c1 {
    status = "okay";
    rk809: pmic@20 {
        compatible = "rockchip,rk809";
        reg = <0x20>;
        interrupt-parent = <&gpio0>;
        interrupts = <7 IRQ_TYPE_LEVEL_LOW>;
        pinctrl-names = "default", "pmic-sleep",
                "pmic-power-off", "pmic-reset";
        pinctrl-0 = <&pmic_int>;
        pinctrl-1 = <&soc_slppin_slp>, <&rk817_slppin_slp>;
        pinctrl-2 = <&soc_slppin_gpio>, <&rk817_slppin_pwrdn>;
        pinctrl-3 = <&soc_slppin_rst>, <&rk817_slppin_rst>;
        rockchip,system-power-controller;
        wakeup-source;
        #clock-cells = <1>;
        clock-output-names = "rk808-clkout1", "rk808-clkout2";
        //fb-inner-reg-idxs = <2>;
        /* 1: rst regs (default in codes), 0: rst the pmic */
        pmic-reset-func = <1>;
        vcc1-supply = <&vcc5v0_sys>;
        vcc2-supply = <&vcc5v0_sys>;
        vcc3-supply = <&vcc5v0_sys>;
        vcc4-supply = <&vcc5v0_sys>;
        vcc5-supply = <&vcc3v3_sys>;
        vcc6-supply = <&vcc3v3_sys>;
        vcc7-supply = <&vcc3v3_sys>;
        vcc8-supply = <&vcc3v3_sys>;
        vcc9-supply = <&vcc5v0_sys>;
        pwrkey {
    status = "okay";
};
pinctrl_rk8xx: pinctrl_rk8xx {
    gpio-controller;
    #gpio-cells = <2>;
    rk817_slppin_null: rk817_slppin_null {
        pins = "gpio_slp";
        function = "pin_fun0";
    };
    rk817_slppin_slp: rk817_slppin_slp {
        pins = "gpio_slp";
        function = "pin_fun1";
    };
    rk817_slppin_pwrdn: rk817_slppin_pwrdn {
        pins = "gpio_slp";
        function = "pin_fun2";
    };
    rk817_slppin_rst: rk817_slppin_rst {
        pins = "gpio_slp";
        function = "pin_fun3";
    };
};
regulators {
    vdd_logic: DCDC_REG1 {
        regulator-always-on;
        regulator-boot-on;
        regulator-min-microvolt = <950000>;
        regulator-max-microvolt = <1350000>;
        regulator-ramp-delay = <6001>;
        regulator-initial-mode = <0x2>;
        regulator-name = "vdd_logic";
        regulator-state-mem {
            regulator-on-in-suspend;
            regulator-suspend-microvolt = <950000>;
        };
    };
    vdd_arm: DCDC_REG2 {
        regulator-always-on;
        regulator-boot-on;
        regulator-min-microvolt = <950000>;
        regulator-max-microvolt = <1350000>;
        regulator-ramp-delay = <6001>;
        regulator-initial-mode = <0x2>;
        regulator-name = "vdd_arm";
        regulator-state-mem {
            regulator-off-in-suspend;
            regulator-suspend-microvolt = <950000>;
        };
    };
            vcc_ddr: RK809_DCDC3@2 {
                .................
            };
            .............................
        };
        rk809_codec: codec {
            #sound-dai-cells = <0>;
            compatible = "rockchip,rk809-codec", "rockchip,rk817-codec";
            clocks = <&cru SCLK_I2S1_OUT>;
            clock-names = "mclk";
            pinctrl-names = "default";
            pinctrl-0 = <&i2s1_2ch_mclk>;
            hp-volume = <20>;
            spk-volume = <3>;
            status = "okay";
        };
    };
};

1. i2c attachment: place the complete RK809 node under the corresponding i2c node and set status = "okay";.

2. Main properties — do not change the following:

compatible = "rockchip,rk809";
reg = <0x20>;
rockchip,system-power-controller;
wakeup-source;
gpio-controller;
#gpio-cells = <2>;

Configurable according to pinctrl rules:

• interrupt-parent: GPIO controller owning pmic_int.
• interrupts: pin index and polarity of pmic_int on that controller.
• pinctrl-names: do not modify; fixed as “default”.
• pinctrl-0: reference to the pmic_int pin defined in pinctrl.

1. rtc, pwrkey and gpio: when selected in menuconfig but not needed, add the corresponding nodes in DTS and explicitly set status = "disabled". The drivers will not load; resulting boot error logs may be ignored in this case. To enable them, remove the nodes or set status = "okay".

2. regulator

• regulator-compatible: Name required for driver matching; changing it causes loading to fail.

• regulator-name: Supply name; match the schematic. regulator_get uses this name.

• regulator-init-microvolt: Initial voltage in U-Boot; ineffective in the kernel.

• regulator-min-microvolt: Minimum adjustable voltage during operation.

• regulator-max-microvolt: Maximum adjustable voltage during operation.

• regulator-initial-mode: DCDC runtime mode, normally 1: 1 = force PWM; 2 = auto PWM/PFM.

• regulator-mode: DCDC suspend mode, normally 2: 1 = force PWM; 2 = auto PWM/PFM.

• regulator-initial-state: Suspend state; must be 3.

• regulator-boot-on: Enable the rail when registering the regulator.

• regulator-always-on: Disallow disabling the rail during operation and enable it at registration.

• regulator-ramp-delay: DCDC voltage rise time; source fixed value 12500.

• regulator-on-in-suspend: Keep powered during suspend; replace with regulator-off-in-suspend to power off.

• regulator-suspend-microvolt: Standby voltage when the rail remains powered.

1. power off: RK809 can shut down directly through an I/O signal. The kernel registers pm_shutdown_prepare_fn for preparation, primarily disabling RTC interrupts and configuring special-I/O IOMUX. The source says actual shutdown occurs “in PCIE”, where pm_power_off directly changes the I/O to power off.

static int rk817_shutdown_prepare(struct rk808 *rk808)
{
    int ret;

    /* close rtc int when power off */
    regmap_update_bits(rk808->regmap,
               RK817_INT_STS_MSK_REG1,
               (0x3 << 5), (0x3 << 5));
    regmap_update_bits(rk808->regmap,
               RK817_RTC_INT_REG,
               (0x3 << 2), (0x0 << 2));

    if (rk808->pins && rk808->pins->p && rk808->pins->power_off) {
        ret = regmap_update_bits(rk808->regmap,
                     RK817_SYS_CFG(3),
                     RK817_SLPPIN_FUNC_MSK,
                     SLPPIN_NULL_FUN);
        if (ret) {
            pr_err("shutdown: config SLPPIN_NULL_FUN error!\n");
            return 0;
        }

        ret = regmap_update_bits(rk808->regmap,
                     RK817_SYS_CFG(3),
                     RK817_SLPPOL_MSK,
                     RK817_SLPPOL_H);
        if (ret) {
            pr_err("shutdown: config RK817_SLPPOL_H error!\n");
            return 0;
        }
        ret = pinctrl_select_state(rk808->pins->p,
                       rk808->pins->power_off);
        if (ret)
            pr_info("%s:failed to activate pwroff state\n",
                __func__);
        else
            return ret;
    }

    /* pmic sleep shutdown function */
    ret = regmap_update_bits(rk808->regmap,
                 RK817_SYS_CFG(3),
                 RK817_SLPPIN_FUNC_MSK, SLPPIN_DN_FUN);
    return ret;
}

1. clk: a node using a RK809 clock references it as follows:

clocks = <&rk809 1>;

First argument: &rk809, fixed. Second argument: clock index, only 0 or 1; 0 = rk809-clkout1, 1 = rk809-clkout2.

Kernel 4.19 DTS configuration

See the kernel 4.4 DTS configuration. Difference: kernel 4.19 no longer needs a gpio child node, but other modules still reference RK809 pins using gpios = <&rk809 0 GPIO_ACTIVE_LOW>;.

2.3 Function interfaces

The following interfaces cover common regulator operations: enable, disable, set voltage and get voltage.

1. Get a regulator:

struct regulator *regulator_get(struct device *dev, const char *id)

Use NULL for dev by default; id matches regulator-name in DTS.

1. Release regulator:

void regulator_put(struct regulator *regulator)

1. Enable regulator:

int regulator_enable(struct regulator *regulator)

1. Disable regulator:

int regulator_disable(struct regulator *regulator)

1. Get voltage regulator:

int regulator_get_voltage(struct regulator *regulator)

1. Set regulator voltage:

int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)

The caller must ensure min_uV = max_uV.

1. Example

struct regulator *rdev_logic;

rdev_logic = regulator_get(NULL, "vdd_logic");      // 获取vdd_logic
regulator_enable(rdev_logic);               // 使能vdd_logic
regulator_set_voltage(rdev_logic, 1100000, 1100000);    // 设置电压1.1v
regulator_disable(rdev_logic);              // 关闭vdd_logic
regulator_put(rdev_logic);              // 释放vdd_logic

Kernel 4.4 and 4.19 also provide regulator interfaces prefixed devm_ to manage allocated resources for developers.

3. Debug

3.1 kernel

Command format is unchanged from kernel 3.10; only the path differs. Kernel 4.4 uses /sys/rk8xx/rk8xx_dbg.

3.2 kernel

Refer to the kernel 4.4 commands.