[PATCH] dt-bindings: clock: Convert nvidia,tegra124-dfll to DT schema

Rob Herring (Arm) posted 1 patch 3 months, 1 week ago
.../bindings/clock/nvidia,tegra124-dfll.txt   | 155 -------------
.../bindings/clock/nvidia,tegra124-dfll.yaml  | 219 ++++++++++++++++++
2 files changed, 219 insertions(+), 155 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
create mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
[PATCH] dt-bindings: clock: Convert nvidia,tegra124-dfll to DT schema
Posted by Rob Herring (Arm) 3 months, 1 week ago
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
---
 .../bindings/clock/nvidia,tegra124-dfll.txt   | 155 -------------
 .../bindings/clock/nvidia,tegra124-dfll.yaml  | 219 ++++++++++++++++++
 2 files changed, 219 insertions(+), 155 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
 create mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml

diff --git a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
deleted file mode 100644
index f7d347385b57..000000000000
--- a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
+++ /dev/null
@@ -1,155 +0,0 @@
-NVIDIA Tegra124 DFLL FCPU clocksource
-
-This binding uses the common clock binding:
-Documentation/devicetree/bindings/clock/clock-bindings.txt
-
-The DFLL IP block on Tegra is a root clocksource designed for clocking
-the fast CPU cluster. It consists of a free-running voltage controlled
-oscillator connected to the CPU voltage rail (VDD_CPU), and a closed loop
-control module that will automatically adjust the VDD_CPU voltage by
-communicating with an off-chip PMIC either via an I2C bus or via PWM signals.
-
-Required properties:
-- compatible : should be one of:
-  - "nvidia,tegra124-dfll": for Tegra124
-  - "nvidia,tegra210-dfll": for Tegra210
-- reg : Defines the following set of registers, in the order listed:
-        - registers for the DFLL control logic.
-        - registers for the I2C output logic.
-        - registers for the integrated I2C master controller.
-        - look-up table RAM for voltage register values.
-- interrupts: Should contain the DFLL block interrupt.
-- clocks: Must contain an entry for each entry in clock-names.
-  See clock-bindings.txt for details.
-- clock-names: Must include the following entries:
-  - soc: Clock source for the DFLL control logic.
-  - ref: The closed loop reference clock
-  - i2c: Clock source for the integrated I2C master.
-- resets: Must contain an entry for each entry in reset-names.
-  See ../reset/reset.txt for details.
-- reset-names: Must include the following entries:
-  - dvco: Reset control for the DFLL DVCO.
-- #clock-cells: Must be 0.
-- clock-output-names: Name of the clock output.
-- vdd-cpu-supply: Regulator for the CPU voltage rail that the DFLL
-  hardware will start controlling. The regulator will be queried for
-  the I2C register, control values and supported voltages.
-
-Required properties for the control loop parameters:
-- nvidia,sample-rate: Sample rate of the DFLL control loop.
-- nvidia,droop-ctrl: See the register CL_DVFS_DROOP_CTRL in the TRM.
-- nvidia,force-mode: See the field DFLL_PARAMS_FORCE_MODE in the TRM.
-- nvidia,cf: Numeric value, see the field DFLL_PARAMS_CF_PARAM in the TRM.
-- nvidia,ci: Numeric value, see the field DFLL_PARAMS_CI_PARAM in the TRM.
-- nvidia,cg: Numeric value, see the field DFLL_PARAMS_CG_PARAM in the TRM.
-
-Optional properties for the control loop parameters:
-- nvidia,cg-scale: Boolean value, see the field DFLL_PARAMS_CG_SCALE in the TRM.
-
-Optional properties for mode selection:
-- nvidia,pwm-to-pmic: Use PWM to control regulator rather then I2C.
-
-Required properties for I2C mode:
-- nvidia,i2c-fs-rate: I2C transfer rate, if using full speed mode.
-
-Required properties for PWM mode:
-- nvidia,pwm-period-nanoseconds: period of PWM square wave in nanoseconds.
-- nvidia,pwm-tristate-microvolts: Regulator voltage in micro volts when PWM
-  control is disabled and the PWM output is tristated. Note that this voltage is
-  configured in hardware, typically via a resistor divider.
-- nvidia,pwm-min-microvolts: Regulator voltage in micro volts when PWM control
-  is enabled and PWM output is low. Hence, this is the minimum output voltage
-  that the regulator supports when PWM control is enabled.
-- nvidia,pwm-voltage-step-microvolts: Voltage increase in micro volts
-  corresponding to a 1/33th increase in duty cycle. Eg the voltage for 2/33th
-  duty cycle would be: nvidia,pwm-min-microvolts +
-  nvidia,pwm-voltage-step-microvolts * 2.
-- pinctrl-0: I/O pad configuration when PWM control is enabled.
-- pinctrl-1: I/O pad configuration when PWM control is disabled.
-- pinctrl-names: must include the following entries:
-  - dvfs_pwm_enable: I/O pad configuration when PWM control is enabled.
-  - dvfs_pwm_disable: I/O pad configuration when PWM control is disabled.
-
-Example for I2C:
-
-clock@70110000 {
-        compatible = "nvidia,tegra124-dfll";
-        reg = <0 0x70110000 0 0x100>, /* DFLL control */
-              <0 0x70110000 0 0x100>, /* I2C output control */
-              <0 0x70110100 0 0x100>, /* Integrated I2C controller */
-              <0 0x70110200 0 0x100>; /* Look-up table RAM */
-        interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
-        clocks = <&tegra_car TEGRA124_CLK_DFLL_SOC>,
-                 <&tegra_car TEGRA124_CLK_DFLL_REF>,
-                 <&tegra_car TEGRA124_CLK_I2C5>;
-        clock-names = "soc", "ref", "i2c";
-        resets = <&tegra_car TEGRA124_RST_DFLL_DVCO>;
-        reset-names = "dvco";
-        #clock-cells = <0>;
-        clock-output-names = "dfllCPU_out";
-        vdd-cpu-supply = <&vdd_cpu>;
-
-        nvidia,sample-rate = <12500>;
-        nvidia,droop-ctrl = <0x00000f00>;
-        nvidia,force-mode = <1>;
-        nvidia,cf = <10>;
-        nvidia,ci = <0>;
-        nvidia,cg = <2>;
-
-        nvidia,i2c-fs-rate = <400000>;
-};
-
-Example for PWM:
-
-clock@70110000 {
-	compatible = "nvidia,tegra124-dfll";
-	reg = <0 0x70110000 0 0x100>, /* DFLL control */
-	      <0 0x70110000 0 0x100>, /* I2C output control */
-	      <0 0x70110100 0 0x100>, /* Integrated I2C controller */
-	      <0 0x70110200 0 0x100>; /* Look-up table RAM */
-	interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
-	clocks = <&tegra_car TEGRA210_CLK_DFLL_SOC>,
-	         <&tegra_car TEGRA210_CLK_DFLL_REF>,
-		 <&tegra_car TEGRA124_CLK_I2C5>;;
-	clock-names = "soc", "ref", "i2c";
-	resets = <&tegra_car TEGRA124_RST_DFLL_DVCO>;
-	reset-names = "dvco";
-	#clock-cells = <0>;
-	clock-output-names = "dfllCPU_out";
-
-	nvidia,sample-rate = <25000>;
-	nvidia,droop-ctrl = <0x00000f00>;
-	nvidia,force-mode = <1>;
-	nvidia,cf = <6>;
-	nvidia,ci = <0>;
-	nvidia,cg = <2>;
-
-	nvidia,pwm-min-microvolts = <708000>; /* 708mV */
-	nvidia,pwm-period-nanoseconds = <2500>; /* 2.5us */
-	nvidia,pwm-to-pmic;
-	nvidia,pwm-tristate-microvolts = <1000000>;
-	nvidia,pwm-voltage-step-microvolts = <19200>; /* 19.2mV */
-
-	pinctrl-names = "dvfs_pwm_enable", "dvfs_pwm_disable";
-	pinctrl-0 = <&dvfs_pwm_active_state>;
-	pinctrl-1 = <&dvfs_pwm_inactive_state>;
-};
-
-/* pinmux nodes added for completeness. Binding doc can be found in:
- * Documentation/devicetree/bindings/pinctrl/nvidia,tegra210-pinmux.yaml
- */
-
-pinmux: pinmux@700008d4 {
-	dvfs_pwm_active_state: dvfs_pwm_active {
-		dvfs_pwm_pbb1 {
-			nvidia,pins = "dvfs_pwm_pbb1";
-			nvidia,tristate = <TEGRA_PIN_DISABLE>;
-		};
-	};
-	dvfs_pwm_inactive_state: dvfs_pwm_inactive {
-		dvfs_pwm_pbb1 {
-			nvidia,pins = "dvfs_pwm_pbb1";
-			nvidia,tristate = <TEGRA_PIN_ENABLE>;
-		};
-	};
-};
diff --git a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
new file mode 100644
index 000000000000..67d99fd89ea9
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
@@ -0,0 +1,219 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/nvidia,tegra124-dfll.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NVIDIA Tegra124 DFLL FCPU clocksource
+
+maintainers:
+  - Joseph Lo <josephl@nvidia.com>
+  - Thierry Reding <treding@nvidia.com>
+  - Tuomas Tynkkynen <ttynkkynen@nvidia.com>
+
+description:
+  The DFLL IP block on Tegra is a root clocksource designed for clocking the
+  fast CPU cluster. It consists of a free-running voltage controlled oscillator
+  connected to the CPU voltage rail (VDD_CPU), and a closed loop control module
+  that will automatically adjust the VDD_CPU voltage by communicating with an
+  off-chip PMIC either via an I2C bus or via PWM signals.
+
+properties:
+  compatible:
+    enum:
+      - nvidia,tegra124-dfll
+      - nvidia,tegra210-dfll
+
+  reg:
+    items:
+      - description: DFLL control logic registers
+      - description: I2C output logic registers
+      - description: Integrated I2C master controller registers
+      - description: Look-up table RAM for voltage register values
+
+  interrupts:
+    maxItems: 1
+
+  "#clock-cells":
+    const: 0
+
+  clocks:
+    items:
+      - description: Clock source for the DFLL control logic
+      - description: Closed loop reference clock
+      - description: Clock source for the integrated I2C master
+
+  clock-names:
+    items:
+      - const: soc
+      - const: ref
+      - const: i2c
+
+  clock-output-names:
+    description: Name of the DFLL CPU clock output
+    items:
+      - const: dfllCPU_out
+
+  resets:
+    minItems: 1
+    maxItems: 2
+
+  reset-names:
+    minItems: 1
+    items:
+      - const: dvco
+      - const: dfll
+
+  vdd-cpu-supply: true
+
+  nvidia,sample-rate:
+    description: Sample rate of the DFLL control loop
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,droop-ctrl:
+    description: Droop control parameter (CL_DVFS_DROOP_CTRL) in TRM
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,force-mode:
+    description: Force mode parameter (DFLL_PARAMS_FORCE_MODE) in TRM
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,cf:
+    description: CF parameter (DFLL_PARAMS_CF_PARAM) in TRM
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,ci:
+    description: CI parameter (DFLL_PARAMS_CI_PARAM) in TRM
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,cg:
+    description: CG parameter (DFLL_PARAMS_CG_PARAM) in TRM
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,cg-scale:
+    description: CG scale flag (DFLL_PARAMS_CG_SCALE) in TRM
+    type: boolean
+
+  nvidia,pwm-to-pmic:
+    description: Use PWM to control regulator rather than I2C
+    type: boolean
+
+  nvidia,i2c-fs-rate:
+    description: I2C full speed transfer rate when using I2C mode
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,pwm-period-nanoseconds:
+    description: Period of PWM square wave in nanoseconds
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,pwm-tristate-microvolts:
+    description: Regulator voltage in microvolts when PWM control is disabled
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,pwm-min-microvolts:
+    description: Regulator voltage in microvolts when PWM control is enabled
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  nvidia,pwm-voltage-step-microvolts:
+    description: Voltage increase in microvolts per duty cycle increment
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  pinctrl-0:
+    description: I/O pad configuration when PWM control is enabled
+
+  pinctrl-1:
+    description: I/O pad configuration when PWM control is disabled
+
+  pinctrl-names:
+    items:
+      - const: dvfs_pwm_enable
+      - const: dvfs_pwm_disable
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - "#clock-cells"
+  - clocks
+  - clock-names
+  - clock-output-names
+  - resets
+  - reset-names
+  - vdd-cpu-supply
+  - nvidia,sample-rate
+  - nvidia,droop-ctrl
+  - nvidia,force-mode
+  - nvidia,cf
+  - nvidia,ci
+  - nvidia,cg
+
+dependencies:
+  nvidia,pwm-to-pmic:
+    - nvidia,pwm-min-microvolts
+    - nvidia,pwm-period-nanoseconds
+    - nvidia,pwm-tristate-microvolts
+    - nvidia,pwm-voltage-step-microvolts
+
+additionalProperties: false
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: nvidia,tegra124-dfll
+    then:
+      properties:
+        resets:
+          maxItems: 1
+
+        reset-names:
+          maxItems: 1
+    else:
+      properties:
+        resets:
+          minItems: 2
+
+        reset-names:
+          minItems: 2
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/reset/tegra124-car.h>
+    #include <dt-bindings/clock/tegra124-car-common.h>
+
+    clock@70110000 {
+        compatible = "nvidia,tegra124-dfll";
+        reg = <0x70110000 0x100>, /* DFLL control */
+              <0x70110000 0x100>, /* I2C output control */
+              <0x70110100 0x100>, /* Integrated I2C controller */
+              <0x70110200 0x100>; /* Look-up table RAM */
+        interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
+        clocks = <&tegra_car TEGRA124_CLK_DFLL_SOC>,
+                 <&tegra_car TEGRA124_CLK_DFLL_REF>,
+                 <&tegra_car TEGRA124_CLK_I2C5>;
+        clock-names = "soc", "ref", "i2c";
+        resets = <&tegra_car TEGRA124_RST_DFLL_DVCO>;
+        reset-names = "dvco";
+        #clock-cells = <0>;
+        clock-output-names = "dfllCPU_out";
+        vdd-cpu-supply = <&reg_vdd_cpu>;
+
+        nvidia,sample-rate = <25000>;
+        nvidia,droop-ctrl = <0x00000f00>;
+        nvidia,force-mode = <1>;
+        nvidia,cf = <6>;
+        nvidia,ci = <0>;
+        nvidia,cg = <2>;
+
+        nvidia,pwm-min-microvolts = <708000>; /* 708mV */
+        nvidia,pwm-period-nanoseconds = <2500>; /* 2.5us */
+        nvidia,pwm-to-pmic;
+        nvidia,pwm-tristate-microvolts = <1000000>;
+        nvidia,pwm-voltage-step-microvolts = <19200>; /* 19.2mV */
+
+        pinctrl-names = "dvfs_pwm_enable", "dvfs_pwm_disable";
+        pinctrl-0 = <&dvfs_pwm_active_state>;
+        pinctrl-1 = <&dvfs_pwm_inactive_state>;
+    };
-- 
2.47.2
Re: [PATCH] dt-bindings: clock: Convert nvidia,tegra124-dfll to DT schema
Posted by Thierry Reding 3 months ago
On Mon, Jun 30, 2025 at 06:26:30PM -0500, Rob Herring (Arm) wrote:
> Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
> ---
>  .../bindings/clock/nvidia,tegra124-dfll.txt   | 155 -------------
>  .../bindings/clock/nvidia,tegra124-dfll.yaml  | 219 ++++++++++++++++++
>  2 files changed, 219 insertions(+), 155 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
>  create mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
> 
> diff --git a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
> deleted file mode 100644
> index f7d347385b57..000000000000
> --- a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
> +++ /dev/null
> @@ -1,155 +0,0 @@
> -NVIDIA Tegra124 DFLL FCPU clocksource
> -
> -This binding uses the common clock binding:
> -Documentation/devicetree/bindings/clock/clock-bindings.txt
> -
> -The DFLL IP block on Tegra is a root clocksource designed for clocking
> -the fast CPU cluster. It consists of a free-running voltage controlled
> -oscillator connected to the CPU voltage rail (VDD_CPU), and a closed loop
> -control module that will automatically adjust the VDD_CPU voltage by
> -communicating with an off-chip PMIC either via an I2C bus or via PWM signals.
> -
> -Required properties:
> -- compatible : should be one of:
> -  - "nvidia,tegra124-dfll": for Tegra124
> -  - "nvidia,tegra210-dfll": for Tegra210
> -- reg : Defines the following set of registers, in the order listed:
> -        - registers for the DFLL control logic.
> -        - registers for the I2C output logic.
> -        - registers for the integrated I2C master controller.
> -        - look-up table RAM for voltage register values.
> -- interrupts: Should contain the DFLL block interrupt.
> -- clocks: Must contain an entry for each entry in clock-names.
> -  See clock-bindings.txt for details.
> -- clock-names: Must include the following entries:
> -  - soc: Clock source for the DFLL control logic.
> -  - ref: The closed loop reference clock
> -  - i2c: Clock source for the integrated I2C master.
> -- resets: Must contain an entry for each entry in reset-names.
> -  See ../reset/reset.txt for details.
> -- reset-names: Must include the following entries:
> -  - dvco: Reset control for the DFLL DVCO.
> -- #clock-cells: Must be 0.
> -- clock-output-names: Name of the clock output.
> -- vdd-cpu-supply: Regulator for the CPU voltage rail that the DFLL
> -  hardware will start controlling. The regulator will be queried for
> -  the I2C register, control values and supported voltages.
> -
> -Required properties for the control loop parameters:
> -- nvidia,sample-rate: Sample rate of the DFLL control loop.
> -- nvidia,droop-ctrl: See the register CL_DVFS_DROOP_CTRL in the TRM.
> -- nvidia,force-mode: See the field DFLL_PARAMS_FORCE_MODE in the TRM.
> -- nvidia,cf: Numeric value, see the field DFLL_PARAMS_CF_PARAM in the TRM.
> -- nvidia,ci: Numeric value, see the field DFLL_PARAMS_CI_PARAM in the TRM.
> -- nvidia,cg: Numeric value, see the field DFLL_PARAMS_CG_PARAM in the TRM.
> -
> -Optional properties for the control loop parameters:
> -- nvidia,cg-scale: Boolean value, see the field DFLL_PARAMS_CG_SCALE in the TRM.
> -
> -Optional properties for mode selection:
> -- nvidia,pwm-to-pmic: Use PWM to control regulator rather then I2C.
> -
> -Required properties for I2C mode:
> -- nvidia,i2c-fs-rate: I2C transfer rate, if using full speed mode.
> -
> -Required properties for PWM mode:
> -- nvidia,pwm-period-nanoseconds: period of PWM square wave in nanoseconds.
> -- nvidia,pwm-tristate-microvolts: Regulator voltage in micro volts when PWM
> -  control is disabled and the PWM output is tristated. Note that this voltage is
> -  configured in hardware, typically via a resistor divider.
> -- nvidia,pwm-min-microvolts: Regulator voltage in micro volts when PWM control
> -  is enabled and PWM output is low. Hence, this is the minimum output voltage
> -  that the regulator supports when PWM control is enabled.
> -- nvidia,pwm-voltage-step-microvolts: Voltage increase in micro volts
> -  corresponding to a 1/33th increase in duty cycle. Eg the voltage for 2/33th
> -  duty cycle would be: nvidia,pwm-min-microvolts +
> -  nvidia,pwm-voltage-step-microvolts * 2.
> -- pinctrl-0: I/O pad configuration when PWM control is enabled.
> -- pinctrl-1: I/O pad configuration when PWM control is disabled.
> -- pinctrl-names: must include the following entries:
> -  - dvfs_pwm_enable: I/O pad configuration when PWM control is enabled.
> -  - dvfs_pwm_disable: I/O pad configuration when PWM control is disabled.
> -
> -Example for I2C:
> -
> -clock@70110000 {
> -        compatible = "nvidia,tegra124-dfll";
> -        reg = <0 0x70110000 0 0x100>, /* DFLL control */
> -              <0 0x70110000 0 0x100>, /* I2C output control */
> -              <0 0x70110100 0 0x100>, /* Integrated I2C controller */
> -              <0 0x70110200 0 0x100>; /* Look-up table RAM */
> -        interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
> -        clocks = <&tegra_car TEGRA124_CLK_DFLL_SOC>,
> -                 <&tegra_car TEGRA124_CLK_DFLL_REF>,
> -                 <&tegra_car TEGRA124_CLK_I2C5>;
> -        clock-names = "soc", "ref", "i2c";
> -        resets = <&tegra_car TEGRA124_RST_DFLL_DVCO>;
> -        reset-names = "dvco";
> -        #clock-cells = <0>;
> -        clock-output-names = "dfllCPU_out";
> -        vdd-cpu-supply = <&vdd_cpu>;
> -
> -        nvidia,sample-rate = <12500>;
> -        nvidia,droop-ctrl = <0x00000f00>;
> -        nvidia,force-mode = <1>;
> -        nvidia,cf = <10>;
> -        nvidia,ci = <0>;
> -        nvidia,cg = <2>;
> -
> -        nvidia,i2c-fs-rate = <400000>;
> -};
> -
> -Example for PWM:
> -
> -clock@70110000 {
> -	compatible = "nvidia,tegra124-dfll";
> -	reg = <0 0x70110000 0 0x100>, /* DFLL control */
> -	      <0 0x70110000 0 0x100>, /* I2C output control */
> -	      <0 0x70110100 0 0x100>, /* Integrated I2C controller */
> -	      <0 0x70110200 0 0x100>; /* Look-up table RAM */
> -	interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
> -	clocks = <&tegra_car TEGRA210_CLK_DFLL_SOC>,
> -	         <&tegra_car TEGRA210_CLK_DFLL_REF>,
> -		 <&tegra_car TEGRA124_CLK_I2C5>;;
> -	clock-names = "soc", "ref", "i2c";
> -	resets = <&tegra_car TEGRA124_RST_DFLL_DVCO>;
> -	reset-names = "dvco";
> -	#clock-cells = <0>;
> -	clock-output-names = "dfllCPU_out";
> -
> -	nvidia,sample-rate = <25000>;
> -	nvidia,droop-ctrl = <0x00000f00>;
> -	nvidia,force-mode = <1>;
> -	nvidia,cf = <6>;
> -	nvidia,ci = <0>;
> -	nvidia,cg = <2>;
> -
> -	nvidia,pwm-min-microvolts = <708000>; /* 708mV */
> -	nvidia,pwm-period-nanoseconds = <2500>; /* 2.5us */
> -	nvidia,pwm-to-pmic;
> -	nvidia,pwm-tristate-microvolts = <1000000>;
> -	nvidia,pwm-voltage-step-microvolts = <19200>; /* 19.2mV */
> -
> -	pinctrl-names = "dvfs_pwm_enable", "dvfs_pwm_disable";
> -	pinctrl-0 = <&dvfs_pwm_active_state>;
> -	pinctrl-1 = <&dvfs_pwm_inactive_state>;
> -};
> -
> -/* pinmux nodes added for completeness. Binding doc can be found in:
> - * Documentation/devicetree/bindings/pinctrl/nvidia,tegra210-pinmux.yaml
> - */
> -
> -pinmux: pinmux@700008d4 {
> -	dvfs_pwm_active_state: dvfs_pwm_active {
> -		dvfs_pwm_pbb1 {
> -			nvidia,pins = "dvfs_pwm_pbb1";
> -			nvidia,tristate = <TEGRA_PIN_DISABLE>;
> -		};
> -	};
> -	dvfs_pwm_inactive_state: dvfs_pwm_inactive {
> -		dvfs_pwm_pbb1 {
> -			nvidia,pins = "dvfs_pwm_pbb1";
> -			nvidia,tristate = <TEGRA_PIN_ENABLE>;
> -		};
> -	};
> -};
> diff --git a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
> new file mode 100644
> index 000000000000..67d99fd89ea9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
> @@ -0,0 +1,219 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/clock/nvidia,tegra124-dfll.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NVIDIA Tegra124 DFLL FCPU clocksource
> +
> +maintainers:
> +  - Joseph Lo <josephl@nvidia.com>
> +  - Thierry Reding <treding@nvidia.com>
> +  - Tuomas Tynkkynen <ttynkkynen@nvidia.com>

Tuomas isn't at NVIDIA anymore, as far as I can tell.

> +
> +description:
> +  The DFLL IP block on Tegra is a root clocksource designed for clocking the
> +  fast CPU cluster. It consists of a free-running voltage controlled oscillator
> +  connected to the CPU voltage rail (VDD_CPU), and a closed loop control module
> +  that will automatically adjust the VDD_CPU voltage by communicating with an
> +  off-chip PMIC either via an I2C bus or via PWM signals.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - nvidia,tegra124-dfll
> +      - nvidia,tegra210-dfll
> +
> +  reg:
> +    items:
> +      - description: DFLL control logic registers
> +      - description: I2C output logic registers
> +      - description: Integrated I2C master controller registers
> +      - description: Look-up table RAM for voltage register values
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  "#clock-cells":
> +    const: 0
> +
> +  clocks:
> +    items:
> +      - description: Clock source for the DFLL control logic
> +      - description: Closed loop reference clock
> +      - description: Clock source for the integrated I2C master
> +
> +  clock-names:
> +    items:
> +      - const: soc
> +      - const: ref
> +      - const: i2c
> +
> +  clock-output-names:
> +    description: Name of the DFLL CPU clock output
> +    items:
> +      - const: dfllCPU_out
> +
> +  resets:
> +    minItems: 1
> +    maxItems: 2
> +
> +  reset-names:
> +    minItems: 1
> +    items:
> +      - const: dvco
> +      - const: dfll
> +
> +  vdd-cpu-supply: true
> +
> +  nvidia,sample-rate:
> +    description: Sample rate of the DFLL control loop
> +    $ref: /schemas/types.yaml#/definitions/uint32

I have a local patch for this and have a few additional restrictions for
some of these properties that I think would make sense to include.

For sample-rate, I have minimum: 12500 and maximum: 25000.

> +
> +  nvidia,droop-ctrl:
> +    description: Droop control parameter (CL_DVFS_DROOP_CTRL) in TRM
> +    $ref: /schemas/types.yaml#/definitions/uint32

For this I have "enum: [ 0x00000f00 ]".

> +
> +  nvidia,force-mode:
> +    description: Force mode parameter (DFLL_PARAMS_FORCE_MODE) in TRM
> +    $ref: /schemas/types.yaml#/definitions/uint32

enum: [ 0, 1, 2, 3 ]

> +
> +  nvidia,cf:
> +    description: CF parameter (DFLL_PARAMS_CF_PARAM) in TRM
> +    $ref: /schemas/types.yaml#/definitions/uint32

minimum: 0, maximum: 63

> +
> +  nvidia,ci:
> +    description: CI parameter (DFLL_PARAMS_CI_PARAM) in TRM
> +    $ref: /schemas/types.yaml#/definitions/uint32

minimum: 0, maximum: 7

> +
> +  nvidia,cg:
> +    description: CG parameter (DFLL_PARAMS_CG_PARAM) in TRM
> +    $ref: /schemas/types.yaml#/definitions/uint32

minimum: 0, maximum: 255

> +
> +  nvidia,cg-scale:
> +    description: CG scale flag (DFLL_PARAMS_CG_SCALE) in TRM
> +    type: boolean
> +
> +  nvidia,pwm-to-pmic:
> +    description: Use PWM to control regulator rather than I2C
> +    type: boolean
> +
> +  nvidia,i2c-fs-rate:
> +    description: I2C full speed transfer rate when using I2C mode
> +    $ref: /schemas/types.yaml#/definitions/uint32

enum: [ 100000, 400000 ]

> +
> +  nvidia,pwm-period-nanoseconds:
> +    description: Period of PWM square wave in nanoseconds
> +    $ref: /schemas/types.yaml#/definitions/uint32

minimum: 1000, maximum: 1000000000

> +
> +  nvidia,pwm-tristate-microvolts:
> +    description: Regulator voltage in microvolts when PWM control is disabled
> +    $ref: /schemas/types.yaml#/definitions/uint32

minimum: 0, maximum: 3300000

> +
> +  nvidia,pwm-min-microvolts:
> +    description: Regulator voltage in microvolts when PWM control is enabled
> +    $ref: /schemas/types.yaml#/definitions/uint32

minimum: 0, maximum: 3300000

> +
> +  nvidia,pwm-voltage-step-microvolts:
> +    description: Voltage increase in microvolts per duty cycle increment
> +    $ref: /schemas/types.yaml#/definitions/uint32

minimum: 0, maximum: 1000000

Though given the additional comment that I added:

+      Voltage increase in micro volts corresponding to a 1/33th increase
+      in duty cycle. Eg the voltage for 2/33th duty cycle would be:
+
+        nvidia,pwm-min-microvolts + nvidia,pwm-voltage-step-microvolts * 2

that maximum should probably be 100000 instead.

Otherwise this looks very similar to what I have.

Thanks for taking care of this.

Thierry
Re: [PATCH] dt-bindings: clock: Convert nvidia,tegra124-dfll to DT schema
Posted by Rob Herring 3 months ago
On Thu, Jul 3, 2025 at 5:26 AM Thierry Reding <thierry.reding@gmail.com> wrote:
>
> On Mon, Jun 30, 2025 at 06:26:30PM -0500, Rob Herring (Arm) wrote:
> > Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
> > ---
> >  .../bindings/clock/nvidia,tegra124-dfll.txt   | 155 -------------
> >  .../bindings/clock/nvidia,tegra124-dfll.yaml  | 219 ++++++++++++++++++
> >  2 files changed, 219 insertions(+), 155 deletions(-)
> >  delete mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
> >  create mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
> > deleted file mode 100644
> > index f7d347385b57..000000000000
> > --- a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
> > +++ /dev/null
> > @@ -1,155 +0,0 @@
> > -NVIDIA Tegra124 DFLL FCPU clocksource
> > -
> > -This binding uses the common clock binding:
> > -Documentation/devicetree/bindings/clock/clock-bindings.txt
> > -
> > -The DFLL IP block on Tegra is a root clocksource designed for clocking
> > -the fast CPU cluster. It consists of a free-running voltage controlled
> > -oscillator connected to the CPU voltage rail (VDD_CPU), and a closed loop
> > -control module that will automatically adjust the VDD_CPU voltage by
> > -communicating with an off-chip PMIC either via an I2C bus or via PWM signals.
> > -
> > -Required properties:
> > -- compatible : should be one of:
> > -  - "nvidia,tegra124-dfll": for Tegra124
> > -  - "nvidia,tegra210-dfll": for Tegra210
> > -- reg : Defines the following set of registers, in the order listed:
> > -        - registers for the DFLL control logic.
> > -        - registers for the I2C output logic.
> > -        - registers for the integrated I2C master controller.
> > -        - look-up table RAM for voltage register values.
> > -- interrupts: Should contain the DFLL block interrupt.
> > -- clocks: Must contain an entry for each entry in clock-names.
> > -  See clock-bindings.txt for details.
> > -- clock-names: Must include the following entries:
> > -  - soc: Clock source for the DFLL control logic.
> > -  - ref: The closed loop reference clock
> > -  - i2c: Clock source for the integrated I2C master.
> > -- resets: Must contain an entry for each entry in reset-names.
> > -  See ../reset/reset.txt for details.
> > -- reset-names: Must include the following entries:
> > -  - dvco: Reset control for the DFLL DVCO.
> > -- #clock-cells: Must be 0.
> > -- clock-output-names: Name of the clock output.
> > -- vdd-cpu-supply: Regulator for the CPU voltage rail that the DFLL
> > -  hardware will start controlling. The regulator will be queried for
> > -  the I2C register, control values and supported voltages.
> > -
> > -Required properties for the control loop parameters:
> > -- nvidia,sample-rate: Sample rate of the DFLL control loop.
> > -- nvidia,droop-ctrl: See the register CL_DVFS_DROOP_CTRL in the TRM.
> > -- nvidia,force-mode: See the field DFLL_PARAMS_FORCE_MODE in the TRM.
> > -- nvidia,cf: Numeric value, see the field DFLL_PARAMS_CF_PARAM in the TRM.
> > -- nvidia,ci: Numeric value, see the field DFLL_PARAMS_CI_PARAM in the TRM.
> > -- nvidia,cg: Numeric value, see the field DFLL_PARAMS_CG_PARAM in the TRM.
> > -
> > -Optional properties for the control loop parameters:
> > -- nvidia,cg-scale: Boolean value, see the field DFLL_PARAMS_CG_SCALE in the TRM.
> > -
> > -Optional properties for mode selection:
> > -- nvidia,pwm-to-pmic: Use PWM to control regulator rather then I2C.
> > -
> > -Required properties for I2C mode:
> > -- nvidia,i2c-fs-rate: I2C transfer rate, if using full speed mode.
> > -
> > -Required properties for PWM mode:
> > -- nvidia,pwm-period-nanoseconds: period of PWM square wave in nanoseconds.
> > -- nvidia,pwm-tristate-microvolts: Regulator voltage in micro volts when PWM
> > -  control is disabled and the PWM output is tristated. Note that this voltage is
> > -  configured in hardware, typically via a resistor divider.
> > -- nvidia,pwm-min-microvolts: Regulator voltage in micro volts when PWM control
> > -  is enabled and PWM output is low. Hence, this is the minimum output voltage
> > -  that the regulator supports when PWM control is enabled.
> > -- nvidia,pwm-voltage-step-microvolts: Voltage increase in micro volts
> > -  corresponding to a 1/33th increase in duty cycle. Eg the voltage for 2/33th
> > -  duty cycle would be: nvidia,pwm-min-microvolts +
> > -  nvidia,pwm-voltage-step-microvolts * 2.
> > -- pinctrl-0: I/O pad configuration when PWM control is enabled.
> > -- pinctrl-1: I/O pad configuration when PWM control is disabled.
> > -- pinctrl-names: must include the following entries:
> > -  - dvfs_pwm_enable: I/O pad configuration when PWM control is enabled.
> > -  - dvfs_pwm_disable: I/O pad configuration when PWM control is disabled.
> > -
> > -Example for I2C:
> > -
> > -clock@70110000 {
> > -        compatible = "nvidia,tegra124-dfll";
> > -        reg = <0 0x70110000 0 0x100>, /* DFLL control */
> > -              <0 0x70110000 0 0x100>, /* I2C output control */
> > -              <0 0x70110100 0 0x100>, /* Integrated I2C controller */
> > -              <0 0x70110200 0 0x100>; /* Look-up table RAM */
> > -        interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
> > -        clocks = <&tegra_car TEGRA124_CLK_DFLL_SOC>,
> > -                 <&tegra_car TEGRA124_CLK_DFLL_REF>,
> > -                 <&tegra_car TEGRA124_CLK_I2C5>;
> > -        clock-names = "soc", "ref", "i2c";
> > -        resets = <&tegra_car TEGRA124_RST_DFLL_DVCO>;
> > -        reset-names = "dvco";
> > -        #clock-cells = <0>;
> > -        clock-output-names = "dfllCPU_out";
> > -        vdd-cpu-supply = <&vdd_cpu>;
> > -
> > -        nvidia,sample-rate = <12500>;
> > -        nvidia,droop-ctrl = <0x00000f00>;
> > -        nvidia,force-mode = <1>;
> > -        nvidia,cf = <10>;
> > -        nvidia,ci = <0>;
> > -        nvidia,cg = <2>;
> > -
> > -        nvidia,i2c-fs-rate = <400000>;
> > -};
> > -
> > -Example for PWM:
> > -
> > -clock@70110000 {
> > -     compatible = "nvidia,tegra124-dfll";
> > -     reg = <0 0x70110000 0 0x100>, /* DFLL control */
> > -           <0 0x70110000 0 0x100>, /* I2C output control */
> > -           <0 0x70110100 0 0x100>, /* Integrated I2C controller */
> > -           <0 0x70110200 0 0x100>; /* Look-up table RAM */
> > -     interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
> > -     clocks = <&tegra_car TEGRA210_CLK_DFLL_SOC>,
> > -              <&tegra_car TEGRA210_CLK_DFLL_REF>,
> > -              <&tegra_car TEGRA124_CLK_I2C5>;;
> > -     clock-names = "soc", "ref", "i2c";
> > -     resets = <&tegra_car TEGRA124_RST_DFLL_DVCO>;
> > -     reset-names = "dvco";
> > -     #clock-cells = <0>;
> > -     clock-output-names = "dfllCPU_out";
> > -
> > -     nvidia,sample-rate = <25000>;
> > -     nvidia,droop-ctrl = <0x00000f00>;
> > -     nvidia,force-mode = <1>;
> > -     nvidia,cf = <6>;
> > -     nvidia,ci = <0>;
> > -     nvidia,cg = <2>;
> > -
> > -     nvidia,pwm-min-microvolts = <708000>; /* 708mV */
> > -     nvidia,pwm-period-nanoseconds = <2500>; /* 2.5us */
> > -     nvidia,pwm-to-pmic;
> > -     nvidia,pwm-tristate-microvolts = <1000000>;
> > -     nvidia,pwm-voltage-step-microvolts = <19200>; /* 19.2mV */
> > -
> > -     pinctrl-names = "dvfs_pwm_enable", "dvfs_pwm_disable";
> > -     pinctrl-0 = <&dvfs_pwm_active_state>;
> > -     pinctrl-1 = <&dvfs_pwm_inactive_state>;
> > -};
> > -
> > -/* pinmux nodes added for completeness. Binding doc can be found in:
> > - * Documentation/devicetree/bindings/pinctrl/nvidia,tegra210-pinmux.yaml
> > - */
> > -
> > -pinmux: pinmux@700008d4 {
> > -     dvfs_pwm_active_state: dvfs_pwm_active {
> > -             dvfs_pwm_pbb1 {
> > -                     nvidia,pins = "dvfs_pwm_pbb1";
> > -                     nvidia,tristate = <TEGRA_PIN_DISABLE>;
> > -             };
> > -     };
> > -     dvfs_pwm_inactive_state: dvfs_pwm_inactive {
> > -             dvfs_pwm_pbb1 {
> > -                     nvidia,pins = "dvfs_pwm_pbb1";
> > -                     nvidia,tristate = <TEGRA_PIN_ENABLE>;
> > -             };
> > -     };
> > -};
> > diff --git a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
> > new file mode 100644
> > index 000000000000..67d99fd89ea9
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.yaml
> > @@ -0,0 +1,219 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/clock/nvidia,tegra124-dfll.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: NVIDIA Tegra124 DFLL FCPU clocksource
> > +
> > +maintainers:
> > +  - Joseph Lo <josephl@nvidia.com>
> > +  - Thierry Reding <treding@nvidia.com>
> > +  - Tuomas Tynkkynen <ttynkkynen@nvidia.com>
>
> Tuomas isn't at NVIDIA anymore, as far as I can tell.
>
> > +
> > +description:
> > +  The DFLL IP block on Tegra is a root clocksource designed for clocking the
> > +  fast CPU cluster. It consists of a free-running voltage controlled oscillator
> > +  connected to the CPU voltage rail (VDD_CPU), and a closed loop control module
> > +  that will automatically adjust the VDD_CPU voltage by communicating with an
> > +  off-chip PMIC either via an I2C bus or via PWM signals.
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - nvidia,tegra124-dfll
> > +      - nvidia,tegra210-dfll
> > +
> > +  reg:
> > +    items:
> > +      - description: DFLL control logic registers
> > +      - description: I2C output logic registers
> > +      - description: Integrated I2C master controller registers
> > +      - description: Look-up table RAM for voltage register values
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  "#clock-cells":
> > +    const: 0
> > +
> > +  clocks:
> > +    items:
> > +      - description: Clock source for the DFLL control logic
> > +      - description: Closed loop reference clock
> > +      - description: Clock source for the integrated I2C master
> > +
> > +  clock-names:
> > +    items:
> > +      - const: soc
> > +      - const: ref
> > +      - const: i2c
> > +
> > +  clock-output-names:
> > +    description: Name of the DFLL CPU clock output
> > +    items:
> > +      - const: dfllCPU_out
> > +
> > +  resets:
> > +    minItems: 1
> > +    maxItems: 2
> > +
> > +  reset-names:
> > +    minItems: 1
> > +    items:
> > +      - const: dvco
> > +      - const: dfll
> > +
> > +  vdd-cpu-supply: true
> > +
> > +  nvidia,sample-rate:
> > +    description: Sample rate of the DFLL control loop
> > +    $ref: /schemas/types.yaml#/definitions/uint32
>
> I have a local patch for this and have a few additional restrictions for
> some of these properties that I think would make sense to include.

Can you send yours then. These are all just bulk conversions with AI
help and minimal time by me to tweak.

Rob