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Configure the shared LCDCAM core clock through guarded LCD and CAM LL APIs, and unify LCD functional clock LL calls around group IDs across supported targets. Co-authored-by: Cursor <cursoragent@cursor.com>
ESP Hardware Abstraction Layer for Clock Tree
Note
This component is currently in beta. Its API, behavior, and compatibility may change at any time and without notice; backward compatibility is not guaranteed. Use caution when integrating into production systems.
Overview
The esp_hal_clock component provides the Hardware Abstraction Layer for the SoC clock tree across ESP-IDF supported targets. It exposes helpers to query and configure clock sources, select roots, and manage clock gates in a target-agnostic way while delegating register details to per-target Low-Level (LL) implementations.
Architecture
The Clock HAL is organized in two layers:
- HAL Layer (Upper): Target-independent logic and APIs to interact with the clock tree (e.g., querying frequencies, switching roots, enabling/disabling gates).
- Low-Level Layer (Bottom): Per-target register accessors defined by:
clk_tree_ll.h— clock source/root select, muxes, dividers, and frequency helpers.clk_gate_ll.h— clock gate enable/disable, reset, and configuration of default clock gate status for peripherals.clkout_channel.h— clock output channel IDs and related helpers used to route internal clocks to GPIOs.
Per-target HAL sources implement SoC-specific behavior in clk_tree_hal.c, using the LL accessors above.
Features
- Query effective frequencies of common clock domains.
- Select and switch clock roots (when supported).
- Configure dividers/multipliers per domain (target-dependent).
- Gate/ungate peripheral clocks via unified helpers.
- Apply default peripheral clock gate configuration during early boot (target-dependent).
- Configure and map on-chip clocks to GPIOs via clock-out channels (
clkout_channel.h) on supported targets.
Usage
This HAL is consumed by ESP-IDF internal components (e.g., esp_hw_support, drivers, bootloader code) to perform clock configuration and queries.
Advanced users may interact with the HAL directly when implementing custom bring-up or performance-sensitive flows. API stability is not guaranteed during beta.
Dependencies
soc: SoC register definitions and clock tree constantshal: Common HAL utilities and macros