feat(openthread): Add support to allocate message pool from PSRAM

docs/en/api-guides/performance/ram-usage.rst

@@ -41,6 +41,7 @@ To minimize static memory use:
 
    - Constant data can be stored in flash memory instead of RAM, thus it is recommended to declare structures, buffers, or other variables as ``const``. This approach may require modifying firmware functions to accept ``const *`` arguments instead of mutable pointer arguments. These changes can also help reduce the stack usage of certain functions.
    :SOC_BT_SUPPORTED: - If using Bluedroid, setting the option :ref:`CONFIG_BT_BLE_DYNAMIC_ENV_MEMORY` will cause Bluedroid to allocate memory on initialization and free it on deinitialization. This does not necessarily reduce the peak memory usage, but changes it from static memory usage to runtime memory usage.
+   - If using OpenThread, enabling the option :ref:`CONFIG_OPENTHREAD_PLATFORM_MSGPOOL_MANAGEMENT` will cause OpenThread to allocate message pool buffers from PSRAM, which will reduce static memory use.
 
 .. _optimize-stack-sizes:
 

docs/zh_CN/api-guides/performance/ram-usage.rst

@@ -41,6 +41,7 @@ ESP-IDF 包含一系列堆 API，可以在运行时测量空闲堆内存，请
 
    - 由于常量数据可以存储在 flash 中，不占用 RAM，建议尽量将结构体、缓冲区或其他变量声明为 ``const``。为此，可能需要修改固件参数，使其接收 ``const *`` 参数而非可变指针参数。以上更改还可以减少某些函数的栈内存使用。
    :SOC_BT_SUPPORTED: - 若使用 Bluedroid，请设置 :ref:`CONFIG_BT_BLE_DYNAMIC_ENV_MEMORY` 选项，Bluedroid 将在初始化时分配内存，并在去初始化时释放内存。这并不一定会降低内存使用峰值，但可以将使用静态内存改为运行时使用动态内存。
+   - 若使用 OpenThread，请设置 :ref:`CONFIG_OPENTHREAD_PLATFORM_MSGPOOL_MANAGEMENT` 选项，OpenThread 将从外部 PSRAM 中分配消息池缓冲区，从而减少对内部静态内存的使用。
 
 .. _optimize-stack-sizes: