1# Copyright (c) 2021 Espressif Systems (Shanghai) Co., Ltd. 2# SPDX-License-Identifier: Apache-2.0 3 4description: Espressif RISC-V CPU 5 6compatible: "espressif,riscv" 7 8include: riscv,cpus.yaml 9 10properties: 11 clock-source: 12 required: true 13 type: int 14 description: | 15 Defines the CPU clock source, each corresponding to different frequencies: 16 - 0: ESP32_CPU_CLK_SRC_XTAL - Uses the external crystal clock typically at 40 MHz. 17 - 1: ESP32_CPU_CLK_SRC_PLL - Utilizes an internal PLL which operates at either 18 320 MHz or 480 MHz. 19 - 2: ESP32_CPU_CLK_SRC_RC_FAST - Employs an internal fast RC oscillator with 20 frequency of 17.5 MHz. 21 enum: 22 - 0 23 - 1 24 - 2 25 26 xtal-freq: 27 required: true 28 type: int 29 description: Value of the external XTAL connected to ESP32. This is typically 40 MHz. 30 enum: 31 - 26000000 32 - 32000000 33 - 40000000 34