From 1e5a53bd16ac501e68463e84023d1bff543cc696 Mon Sep 17 00:00:00 2001 From: Lucas Tanure Date: Sat, 29 Aug 2026 10:47:57 +0100 Subject: [PATCH] arm64: dts: amlogic: t7: khadas-vim4: add the PWM-driven supplies The board powers its two CPU clusters, the GPU, the NPU, the memory and the always-on domain from regulators steered by PWM outputs. None of them were described, so Linux treated those outputs as unused and switched them off part way through boot. The supplies then drifted away from the levels the bootloader had set, which showed up as random hangs and memory corruption. Describe each supply so it has an owner and is left alone. The voltage ranges are read off the feedback networks on the board schematic. VDDNPU is deliberately not the range in Amlogic's own device tree: this board fits a different feedback resistor, which puts it about 40mV higher at both ends. Fixes: 8c45bf9ae4ef ("arm64: dts: amlogic: t7: khadas-vim4: Add power regulators") Assisted-by: Claude:claude-opus-5 Signed-off-by: Lucas Tanure Reviewed-by: Neil Armstrong Link: https://patch.msgid.link/20260829094758.23248-4-tanure@linux.com Signed-off-by: Neil Armstrong --- .../amlogic/amlogic-t7-a311d2-khadas-vim4.dts | 110 +++++++++++++++++- 1 file changed, 109 insertions(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts b/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts index c94afaaf8826..77abfd555ec5 100644 --- a/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts +++ b/arch/arm64/boot/dts/amlogic/amlogic-t7-a311d2-khadas-vim4.dts @@ -104,6 +104,66 @@ vcc5v0_usb: regulator-vcc-usb { enable-active-high; }; + vdd_ddr: regulator-vddddr { + /* + * SY8003ADFC Regulator. + */ + compatible = "pwm-regulator"; + regulator-name = "VDDDDR"; + regulator-min-microvolt = <690000>; + regulator-max-microvolt = <890000>; + pwm-supply = <&dc_in>; + pwms = <&pwm_ao_gh 0 1500 0>; + pwm-dutycycle-range = <100 0>; + regulator-boot-on; + regulator-always-on; + }; + + vdd_ee: regulator-vddee { + /* + * MP8756GD Regulator. + */ + compatible = "pwm-regulator"; + regulator-name = "VDDEE"; + regulator-min-microvolt = <700000>; + regulator-max-microvolt = <922000>; + pwm-supply = <&dc_in>; + pwms = <&pwm_ao_ab 0 1500 0>; + pwm-dutycycle-range = <100 0>; + regulator-boot-on; + regulator-always-on; + }; + + vdd_gpu: regulator-vddgpu { + /* + * SY8003ADFC Regulator. + */ + compatible = "pwm-regulator"; + regulator-name = "VDDGPU"; + regulator-min-microvolt = <700000>; + regulator-max-microvolt = <922000>; + pwm-supply = <&dc_in>; + pwms = <&pwm_ao_ef 0 1500 0>; + pwm-dutycycle-range = <100 0>; + regulator-boot-on; + regulator-always-on; + }; + + vdd_npu: regulator-vddnpu { + /* + * SY8003ADFC Regulator. + */ + compatible = "pwm-regulator"; + regulator-name = "VDDNPU"; + regulator-min-microvolt = <733000>; + regulator-max-microvolt = <933000>; + pwm-supply = <&dc_in>; + pwms = <&pwm_ao_ef 1 1500 0>; + pwm-dutycycle-range = <100 0>; + regulator-boot-on; + regulator-always-on; + }; + vddao_1v8: regulator-vddao-1v8 { compatible = "regulator-fixed"; regulator-name = "VDDAO_1V8"; @@ -122,6 +182,36 @@ vddao_3v3: regulator-vddao-3v3 { regulator-always-on; }; + vddcpu_a: regulator-vddcpu-a { + /* + * MP8756GD Regulator. + */ + compatible = "pwm-regulator"; + regulator-name = "VDDCPU_A"; + regulator-min-microvolt = <689000>; + regulator-max-microvolt = <1049000>; + pwm-supply = <&dc_in>; + pwms = <&pwm_ao_cd 1 1500 0>; + pwm-dutycycle-range = <100 0>; + regulator-boot-on; + regulator-always-on; + }; + + vddcpu_b: regulator-vddcpu-b { + /* + * MP8756GD Regulator. + */ + compatible = "pwm-regulator"; + regulator-name = "VDDCPU_B"; + regulator-min-microvolt = <689000>; + regulator-max-microvolt = <1049000>; + pwm-supply = <&dc_in>; + pwms = <&pwm_ao_ab 1 1500 0>; + pwm-dutycycle-range = <100 0>; + regulator-boot-on; + regulator-always-on; + }; + vddio_1v8: regulator-vddio-1v8 { compatible = "regulator-fixed"; regulator-name = "VDDIO_1V8"; @@ -172,9 +262,27 @@ &pwm_ab { pinctrl-names = "default"; }; +&pwm_ao_ab { + status = "okay"; + pinctrl-0 = <&pwm_ao_a_pins>, <&pwm_ao_b_pins>; + pinctrl-names = "default"; +}; + &pwm_ao_cd { status = "okay"; - pinctrl-0 = <&pwm_ao_c_d_pins>; + pinctrl-0 = <&pwm_ao_c_d_pins>, <&pwm_ao_d_pins>; + pinctrl-names = "default"; +}; + +&pwm_ao_ef { + status = "okay"; + pinctrl-0 = <&pwm_ao_e_pins>, <&pwm_ao_f_pins>; + pinctrl-names = "default"; +}; + +&pwm_ao_gh { + status = "okay"; + pinctrl-0 = <&pwm_ao_g_e_pins>; pinctrl-names = "default"; };