789ce684c9
Before: The cache won't be disabled when XIP on psram. But during flash erasing/programming, read data will be courrupt. When XIP in psram is enabled, the image is not mapped to the cache so usually there will be no flash access. The only way to read from flash is via the driver or use mmap. The driver has protection during erasing, while th mmap region not. Now: Mmap APIs provide a flag to make mmap->unmap region mutually exclusive to flash erase/programming when XIP from psram. SPI Flash write APIs will benefit from this. When the flag is used, no concurrent access to mapped region will happen while writing; otherwise the cache will be disable to avoid data corruption. Most ESP-IDF APIs calls mmap with this flag. As for users calling mmap-like APIs directly, they can choose whether to enable this by a flag. Closes https://github.com/espressif/esp-idf/issues/14897
| Supported Targets | ESP32 | ESP32-C2 | ESP32-C3 | ESP32-C5 | ESP32-C6 | ESP32-C61 | ESP32-H2 | ESP32-H21 | ESP32-H4 | ESP32-P4 | ESP32-S2 | ESP32-S3 | ESP32-S31 |
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Partition Memory Map Example
This example demonstrates how to use esp_partition_mmap to configure MMU and map a partition into memory address space for read operations.
Example Flow
The example uses a custom partition table, with a data partition storage used for demonstration. Before mapping this partition to memory,
data is written to the partition used for verification.
The partition API function esp_partition_mmap is used to get a pointer to the mapped memory region and a handle to the mapping. The pointer is used to transparently read back the
verification data written previously. Once the data written and read are verified to be the same, the function spi_flash_munmap is used to release the mapping.
Output
I (309) example: Written sample data to partition: ESP-IDF Partition Memory Map Example
I (309) example: Mapped partition to data memory address 0x3f410000
I (319) example: Read sample data from partition using mapped memory: ESP-IDF Partition Memory Map Example
I (329) example: Data matches
I (329) example: Unmapped partition from data memory
I (339) example: Example end
Others
Detailed functional description of partition API is provided in documentation.
See the README.md file in the upper level 'examples' directory for more information about examples.