60bb5c913d
1. Clean up clk usage in IDF, replace rtc_clk_xtal/apb_freq_get with upper level API esp_clk_xtal/apb_freq 2. Fix small errors and wrong comments related to clock 3. Add clk_tree_defs.h to provide an unified clock id for each chip Modify the NGed drivers to adopt new clock ids
soc
The soc component provides hardware description for targets supported by ESP-IDF.
- `xxx_reg.h` - defines registers related to the hardware
- `xxx_struct.h` - hardware description in C `struct`
- `xxx_channel.h` - definitions for hardware with multiple channels
- `xxx_caps.h` - features/capabilities of the hardware
- `xxx_pins.h` - pin definitions
- `xxx_periph.h/*.c` - includes all headers related to a peripheral; declaration and definition of IO mapping for that hardware