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TSC Functionality Enablement for Monaco and Lemans

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Overview

This document outlines the steps required to enable TSC (Timestamp Counter) functionality on Monaco (QCS8300) and Lemans (SA8775P) platforms. It includes device tree configurations, driver enablement, and target-specific notes.

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1. Monaco Device Configuration

The following updates are required on the Monaco target to enable TSC functionality.

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1.1 GPIO Configuration

Add the following GPIO pin configuration. Ensure these pins are reworked for ETU functionality. Add this under the tlmm node: 
cci_async_default: cci-async-state {
       pins = "gpio63", "gpio64";
       function = "cci_async";
       drive-strength = <2>;
       bias-disable;
};

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1.2 TSC Node Configuration

Add this under the soc node: 
tsc@1c80000 {
       compatible = "qcom,tsc";
       reg = <0x0 0x01c80000 0x0 0x2000>,
             <0x0 0x01c90000 0x0 0x10000>;
       reg-names = "tsc", "etu";
       clocks = <&gcc GCC_TSCSS_AHB_CLK>,
                <&gcc GCC_TSCSS_GLOBAL_CNTR_CLK>,
                <&gcc GCC_TSCSS_ETU_CLK>;
       clock-names = "cfg_ahb", "cntr", "etu";
       assigned-clocks = <&gcc GCC_TSCSS_GLOBAL_CNTR_CLK>,
                         <&gcc GCC_TSCSS_ETU_CLK>;
       assigned-clock-rates = <15625000>, <15625000>;
       qcom,tsc-nsec-update;
       interrupts = <GIC_SPI 766 IRQ_TYPE_EDGE_RISING>;
       interrupt-names = "etu_summary_irq";
       qcom,etu-slice = <10 11>;
       qcom,etu-event-sel = <10 11>;
       qcom,etu-event-names = "gps_pps", "tod_pps";
       pinctrl-names = "default";
       pinctrl-0 = <&cci_async_default>;
};

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1.3 Kernel Configuration

Ensure the TSC driver configuration is enabled: 
CONFIG_PTP_QCOM_CLOCK_TSC=m

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2. Lemans (SA8775P) Configuration

On the Lemans target, the required TSC configurations are already present in the release in the lemans-staging.dtso overlay. Ensure the appropriate overlay is loaded to enable TSC functionality on the Lemans platform.

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Summary

To enable TSC functionality:

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Monaco (QCS8300)

  1. Add the required cci_async pin configuration under the tlmm node.
  2. Add the tsc@1c80000 node under the soc node.
  3. Enable the TSC driver using:
CONFIG_PTP_QCOM_CLOCK_TSC=m

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Lemans (SA8775P)

  1. Use the existing lemans-staging.dtso overlay.
  2. Ensure the correct overlay is loaded in the target build or boot flow.