i want to map memory in esp32 suppose address of memory is 3F40_0000 for the same address i am searching compatible address for controller.
The memory of the ESP32 has already been mapped.
No need for you to map the ESP32's memory.
There are pointers you can use, look up c++ pointers.
You can read get DMA info from the API Reference - ESP32 - — ESP-IDF Programming Guide latest documentation (espressif.com).
I've used pointers and the only way to access PSRAM is through memory pointers.
SPI and I2C have DMA with an ESP32.