[Clock] Inaccurate Calibration of RC_FAST_CLK Clock

Affected revisions: v0.0

Description

In the ESP32-C6 chip, the frequency of the RC_FAST_CLK clock source is too close to the reference clock (40 MHz XTAL_CLK) frequency, making it impossible to calibrate accurately. This may affect peripherals that use RC_FAST_CLK and have stringent requirements for its accurate clock frequency.

For peripherals using RC_FAST_CLK, please refer to ESP32-C6 Technical Reference Manual > Chapter Reset and Clock [PDF].

Workarounds

Use other clock sources instead of RC_FAST_CLK.

Solution

Fixed in chip revision v0.1.