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Subject[PATCH 01/13] clk: tegra: Add binding for the Tegra124 DFLL clocksource
Date
The DFLL is the main clocksource for the fast CPU cluster on Tegra124
and also provides automatic CPU rail voltage scaling as well. The DFLL
is a separate IP block from the usual Tegra124 clock-and-reset
controller, so it gets its own node in the device tree.

Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
---
.../bindings/clock/nvidia,tegra124-dfll.txt | 86 ++++++++++++++++++++++
1 file changed, 86 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt

diff --git a/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
new file mode 100644
index 0000000..cf89802
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/nvidia,tegra124-dfll.txt
@@ -0,0 +1,86 @@
+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 "nvidia,tegra124-dfll-fcpu"
+- 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 ../clocks/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.
+- #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.
+
+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.
+- nvidia,cg-scale: Boolean value, see the field DFLL_PARAMS_CG_SCALE in the TRM.
+
+Required properties for I2C mode:
+- nvidia,pmic-i2c-address: I2C address of the PMIC that controls the VDD_CPU
+ voltage.
+- nvidia,i2c-10-bit-addresses: Boolean, whether to use 10-bit I2C addressing.
+- nvidia,pmic-i2c-voltage-register: Register of the PMIC that controls the
+ VDD_CPU voltage.
+- nvidia,i2c-fs-rate: I2C transfer rate, if using FS mode.
+- nvidia,pmic-voltage-table: Array of 2-tuples. Each entry should have the
+ form <register-value voltage-in-uV>, indicating the register value that
+ needs to be programmed to the PMIC for changing the VDD_CPU voltage to
+ the specified voltage. The table must be in ascending order by the voltage.
+
+Example:
+
+dfll@0,70110000 {
+ 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";
+ #clock-cells = <0>;
+ clock-output-names = "dfllCPU_out";
+ vdd_cpu-supply = <&vdd_cpu>;
+ status = "okay";
+
+ 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>;
+ nvidia,pmic-i2c-address = <0x40>;
+ nvidia,pmic-i2c-voltage-register = <0x00>;
+ nvidia,pmic-voltage-table =
+ <0x1e 700000>,
+ <0x1f 710000>,
+ /* etc... */
+ <0x63 1390000>,
+ <0x64 1400000>;
+};
--
1.8.1.5


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