This commit implements a workaround that allows ESP32-C5 to run at 240MHz CPU frequency
normally, while automatically reducing CPU frequency during encrypted flash writes to
ensure correct operation. The frequency limit is chip revision dependent:
- v1.2 and above: limited to 160MHz during encrypted writes
- v1.0 and below: limited to 80MHz during encrypted writes
Key implementation details:
- Frequency limiting is triggered automatically when esp_flash_write_encrypted() is called
- Uses start() flags (ESP_FLASH_START_FLAG_LIMIT_CPU_FREQ) to integrate with OS layer
- Works with both PM enabled and disabled configurations
- Frequency is automatically restored after encrypted write completes
- For ESP32-C5 with 120MHz flash, Flash clock and timing registers are adjusted when
CPU frequency is reduced to 80MHz
- SPI1 timing registers are configured during frequency switching since encrypted writes
use SPI1 and must work correctly at reduced CPU frequencies
Code improvements:
- Use SOC_MSPI_FREQ_AXI_CONSTRAINED capability macro instead of hardcoded chip checks
- Control workaround via Kconfig (CONFIG_PM_WORKAROUND_FREQ_LIMIT_ENABLED) instead of
hardcoded macros
- Add comprehensive test cases covering various PM configurations and edge cases
This workaround enables ESP32-C5 applications to benefit from 240MHz CPU performance
while maintaining reliable encrypted flash write functionality.
There is a periodically yield in the esp_flash driver, to ensure the
cache will not be disabled for too long on ESP32.
On ESP32-S2 and later, we need to support more different kind of yield:
1. polling conditions, including timeout, SW read request, etc.
2. wait for events, including HW done/error/auto-suspend, timeout
semaphore, etc.
The check_yield() and yield() is separated into two parts, because we
may need to insert suspend, etc. between them.
Including:
1. Change the write bytes/read bytes parameter in the host driver into slicers to meet the requirements of complicated cases.
2. Refactor the esp_flash_api code a bit so that we can use the code in the ROM laster
3. Provide get_temp_buffer and release_temp_buffer in the os_functions when the buffer passed by application cannot be used directly.
4. Make timeout of operations configurable in the chip_driver.
5. Make dummy number configurable.
Previously would try allocate buffer of minimum size 16KB not maximum size 16KB, causing
out of memory errors for any large reads, or if less than 16KB contiguous free heap.
Also, if using legacy API and internal allocation failed then implementation would abort()
instead of returning the error to the caller.
Added test for using large buffers in PSRAM.
Closes https://github.com/espressif/esp-idf/issues/4769
Also reported on forum: https://esp32.com/viewtopic.php?f=13&t=14304&p=55972
There used to be dummy phase before out phase in common command
transactions. This corrupts the data.
The code before never actually operate (clear) the QE bit, once it finds
the QE bit is set. It's hard to check whether the QE set/disable
functions work well.
This commit:
1. Cancel the dummy phase
2. Set and clear the QE bit according to chip settings, allowing tests
for QE bits. However for some chips (Winbond for example), it's not
forced to clear the QE bit if not able to.
3. Also refactor to allow chip_generic and other chips to share the same
code to read and write qe bit; let common command and read command share
configure_host_io_mode.
4. Rename read mode to io mode since maybe we will write data with quad
mode one day.
During coredump, dangerous-area-checking should be disabled, and cache
disabling should be replaced by a safer version.
Dangerous-area-checking used to be in the HAL, but it seems to be more
fit to os functions. So it's moved to os functions. Interfaces are
provided to switch between os functions during coredump.
When legacy mode is used, the coredump still fails during linking
because "esp_flash_init_default_chip", "esp_flash_app_init" and
"esp_flash_default_chip " are not compiled and linked.
Instead of using ``if`` macros in callers, these functions are protected
by ``if`` macros in the header, and also not compiled in the sources.
"esp_flash_default_chip" variable is compiled with safe default value.
Add support for get write protection support, fixed the duplicated
set_write_protection link.
All the write_protection check in the top layer are removed. The lower
levels (chip) should ensure to disable write protection before the
operation start.
Xiao Xufeng
Adam Múdry
C.S.M
Armando
Ivan Grokhotkov
Angus Gratton
Anton Maklakov