On flash program operation (either erase or write), if corresponding address has
cache mapping present then cache is explicitly flushed (for both pro and app cpu)
Closes https://github.com/espressif/esp-idf/issues/2146
Without this, it's possible for stale information to be read from
cache via mmap, even if the MMU table entry had been invalidated
prior to writing flash (if the same MMU table entry was re-used after
writing flash.)
The following issues mentioned during MR!341 review were fixed:
1) Core dump test application description
2) Usage of CONFIG_ESP32_ENABLE_COREDUMP_TO_FLASH and CONFIG_ESP32_ENABLE_COREDUMP_TO_UART
3) FLASH_GUARD_START macro usage is fixed in flash API
4) Core dump module logging facility
5) cache util functions doc updated
6) interactive delay before print core dump to uart
7) core dump partion support in build system
1) PS is fixed up to allow GDB backtrace to work properly
2) MR!341 discussion: in core dump module: esp_panicPutXXX was replaced by ets_printf.
3) MR!341 discussion: core dump flash magic number was changed.
4) MR!341 discussion: SPI flash access API was redesigned to allow flexible critical section management.
5) test app for core dump feature was added
6) fixed base64 file reading issues on Windows platform
7) now raw bin core file is deleted upon core loader failure by epscoredump.py
Complimentary changes:
1) Partition table definitions files with core dump partition
2) Special sub-type for core dump partition
3) Special version of spi_flash_xxx
4) espcoredump.py is script to get core dump from flash and print useful info
5) FreeRTOS API was extended to get tasks snapshots
