ESP32: Add menuconfig to use PSRAM for Matter memory allocation (#37482)

* ESP32: Add menuconfig to use PSRAM for Matter memory allocation

* Restyled by clang-format

* review changes

* split to 3 separate files

* doc changes

* add comment on MemoryInternalCheckPointer

---------

Co-authored-by: Restyled.io <commits@restyled.io>

Author: wqx6

config/esp32/args.gni

@@ -29,6 +29,8 @@ lwip_platform = "external"
 chip_inet_config_enable_tcp_endpoint = false
 chip_inet_config_enable_udp_endpoint = true
 
+chip_config_memory_management = "platform"
+
 custom_toolchain = "//third_party/connectedhomeip/config/esp32/toolchain:esp32"
 
 # Avoid constraint forcing for ESP32:

config/esp32/components/chip/CMakeLists.txt

@@ -149,6 +149,14 @@ if(CONFIG_ENABLE_ICD_SERVER)
     endif()
 endif()
 
+if(CONFIG_CHIP_MEM_ALLOC_MODE_INTERNAL)
+    chip_gn_arg_append("chip_memory_alloc_mode"               "\"internal\"")
+elseif(CONFIG_CHIP_MEM_ALLOC_MODE_EXTERNAL)
+    chip_gn_arg_append("chip_memory_alloc_mode"               "\"external\"")
+elseif(CONFIG_CHIP_MEM_ALLOC_MODE_DEFAULT)
+    chip_gn_arg_append("chip_memory_alloc_mode"               "\"default\"")
+endif()
+
 if(CONFIG_ENABLE_PW_RPC)
     string(APPEND chip_gn_args "import(\"//build_overrides/pigweed.gni\")\n")
     chip_gn_arg_append("remove_default_configs"             "[\"//third_party/connectedhomeip/third_party/pigweed/repo/pw_build:toolchain_cpp_standard\"]")

config/esp32/components/chip/Kconfig

@@ -191,6 +191,27 @@ menu "CHIP Core"
                 Enable dynamic server to handle a different interaction model dispatch.
                 Can be implied when users do not want to use the same server clusters.
 
+        choice CHIP_MEM_ALLOC_MODE
+            prompt "Memory allocation strategy"
+            default CHIP_MEM_ALLOC_MODE_DEFAULT
+            help
+                Strategy for Matter memory management
+                - Internal DRAM memory only
+                - External SPIRAM memory only
+                - Either internal or external memory based on default malloc() behavior in ESP-IDF
+
+            config CHIP_MEM_ALLOC_MODE_INTERNAL
+                bool "Internal memory"
+
+            config CHIP_MEM_ALLOC_MODE_EXTERNAL
+                bool "External SPIRAM"
+                depends on SPIRAM_USE_CAPS_ALLOC || SPIRAM_USE_MALLOC
+
+            config CHIP_MEM_ALLOC_MODE_DEFAULT
+                bool "Default alloc mode"
+
+        endchoice # CHIP_MEM_ALLOC_MODE
+
     endmenu # "General Options"
 
     menu "Networking Options"

examples/platform/esp32/common/CommonDeviceCallbacks.cpp

@@ -95,7 +95,11 @@ void CommonDeviceCallbacks::DeviceEventCallback(const ChipDeviceEvent * event, i
         break;
     }
 
-    ESP_LOGI(TAG, "Current free heap: %u\n", static_cast<unsigned int>(heap_caps_get_free_size(MALLOC_CAP_8BIT)));
+    ESP_LOGI(TAG, "Current free heap: Internal: %u/%u External: %u/%u",
+             static_cast<unsigned int>(heap_caps_get_free_size(MALLOC_CAP_8BIT | MALLOC_CAP_INTERNAL)),
+             static_cast<unsigned int>(heap_caps_get_total_size(MALLOC_CAP_8BIT | MALLOC_CAP_INTERNAL)),
+             static_cast<unsigned int>(heap_caps_get_free_size(MALLOC_CAP_8BIT | MALLOC_CAP_SPIRAM)),
+             static_cast<unsigned int>(heap_caps_get_total_size(MALLOC_CAP_8BIT | MALLOC_CAP_SPIRAM)));
 }
 
 void CommonDeviceCallbacks::OnInternetConnectivityChange(const ChipDeviceEvent * event)

src/platform/ESP32/BUILD.gn

@@ -15,6 +15,7 @@
 import("//build_overrides/chip.gni")
 
 import("${chip_root}/src/inet/inet.gni")
+import("${chip_root}/src/lib/core/core.gni")
 import("${chip_root}/src/platform/device.gni")
 
 assert(chip_device_platform == "esp32")
@@ -33,6 +34,7 @@ declare_args() {
   chip_use_esp32_ecdsa_peripheral = false
   chip_enable_ethernet = false
   chip_enable_route_hook = false
+  chip_memory_alloc_mode = "default"
 }
 
 defines = [
@@ -81,6 +83,16 @@ static_library("ESP32") {
     "${chip_root}/src/platform:platform_base",
   ]
 
+  if (chip_config_memory_management == "platform") {
+    if (chip_memory_alloc_mode == "internal") {
+      sources += [ "CHIPMem-PlatformInternal.cpp" ]
+    } else if (chip_memory_alloc_mode == "external") {
+      sources += [ "CHIPMem-PlatformExternal.cpp" ]
+    } else {
+      sources += [ "CHIPMem-PlatformDefault.cpp" ]
+    }
+  }
+
   if (chip_enable_ota_requestor) {
     sources += [
       "OTAImageProcessorImpl.cpp",

src/platform/ESP32/CHIPMem-PlatformDefault.cpp

@@ -0,0 +1,67 @@
+/*
+ *
+ *    Copyright (c) 2025 Project CHIP Authors
+ *    All rights reserved.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include <lib/support/CHIPMem.h>
+#include <platform/CHIPDeviceLayer.h>
+
+#include <esp_heap_caps.h>
+#include <stdlib.h>
+
+namespace chip {
+namespace Platform {
+
+CHIP_ERROR MemoryAllocatorInit(void * buf, size_t bufSize)
+{
+    return CHIP_NO_ERROR;
+}
+
+void MemoryAllocatorShutdown() {}
+
+void * MemoryAlloc(size_t size)
+{
+    return malloc(size);
+}
+
+void * MemoryAlloc(size_t size, bool isLongTermAlloc)
+{
+    return malloc(size);
+}
+
+void * MemoryCalloc(size_t num, size_t size)
+{
+    return calloc(num, size);
+}
+
+void * MemoryRealloc(void * p, size_t size)
+{
+    return realloc(p, size);
+}
+
+void MemoryFree(void * p)
+{
+    free(p);
+}
+
+bool MemoryInternalCheckPointer(const void * p, size_t min_size)
+{
+    // We don't have a way to know if p is allocated from the heap, just do a null check here.
+    return (p != nullptr);
+}
+
+} // namespace Platform
+} // namespace chip

src/platform/ESP32/CHIPMem-PlatformExternal.cpp

@@ -0,0 +1,67 @@
+/*
+ *
+ *    Copyright (c) 2025 Project CHIP Authors
+ *    All rights reserved.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include <lib/support/CHIPMem.h>
+#include <platform/CHIPDeviceLayer.h>
+
+#include <esp_heap_caps.h>
+#include <stdlib.h>
+
+namespace chip {
+namespace Platform {
+
+CHIP_ERROR MemoryAllocatorInit(void * buf, size_t bufSize)
+{
+    return CHIP_NO_ERROR;
+}
+
+void MemoryAllocatorShutdown() {}
+
+void * MemoryAlloc(size_t size)
+{
+    return heap_caps_malloc(size, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
+}
+
+void * MemoryAlloc(size_t size, bool isLongTermAlloc)
+{
+    return heap_caps_malloc(size, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
+}
+
+void * MemoryCalloc(size_t num, size_t size)
+{
+    return heap_caps_calloc(num, size, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
+}
+
+void * MemoryRealloc(void * p, size_t size)
+{
+    return heap_caps_realloc(p, size, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
+}
+
+void MemoryFree(void * p)
+{
+    heap_caps_free(p);
+}
+
+bool MemoryInternalCheckPointer(const void * p, size_t min_size)
+{
+    // We don't have a way to know if p is allocated from the heap, just do a null check here.
+    return (p != nullptr);
+}
+
+} // namespace Platform
+} // namespace chip

src/platform/ESP32/CHIPMem-PlatformInternal.cpp

@@ -0,0 +1,67 @@
+/*
+ *
+ *    Copyright (c) 2025 Project CHIP Authors
+ *    All rights reserved.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include <lib/support/CHIPMem.h>
+#include <platform/CHIPDeviceLayer.h>
+
+#include <esp_heap_caps.h>
+#include <stdlib.h>
+
+namespace chip {
+namespace Platform {
+
+CHIP_ERROR MemoryAllocatorInit(void * buf, size_t bufSize)
+{
+    return CHIP_NO_ERROR;
+}
+
+void MemoryAllocatorShutdown() {}
+
+void * MemoryAlloc(size_t size)
+{
+    return heap_caps_malloc(size, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT);
+}
+
+void * MemoryAlloc(size_t size, bool isLongTermAlloc)
+{
+    return heap_caps_malloc(size, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT);
+}
+
+void * MemoryCalloc(size_t num, size_t size)
+{
+    return heap_caps_calloc(num, size, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT);
+}
+
+void * MemoryRealloc(void * p, size_t size)
+{
+    return heap_caps_realloc(p, size, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT);
+}
+
+void MemoryFree(void * p)
+{
+    heap_caps_free(p);
+}
+
+bool MemoryInternalCheckPointer(const void * p, size_t min_size)
+{
+    // We don't have a way to know if p is allocated from the heap, just do a null check here.
+    return (p != nullptr);
+}
+
+} // namespace Platform
+} // namespace chip