Remove SPI RAM requirement

sdkconfig.defaults

@@ -1,3 +1,7 @@
+# ESP32-S3 target
+CONFIG_IDF_TARGET="esp32s3"
+CONFIG_IDF_TARGET_ESP32S3=y
+
 # ESP Event Loop on Linux
 CONFIG_ESP_EVENT_POST_FROM_ISR=n
 CONFIG_ESP_EVENT_POST_FROM_IRAM_ISR=n
@@ -11,16 +15,17 @@ CONFIG_ESP_TLS_SKIP_SERVER_CERT_VERIFY=y
 CONFIG_MBEDTLS_SSL_PROTO_DTLS=y
 
 # libpeer requires large stack allocations
-CONFIG_ESP_MAIN_TASK_STACK_SIZE=16384
+CONFIG_ESP_MAIN_TASK_STACK_SIZE=10240
 
 # Defaults to partitions.csv
 CONFIG_PARTITION_TABLE_CUSTOM=y
 
 # Set highest CPU Freq
 CONFIG_ESP_DEFAULT_CPU_FREQ_MHZ_240=y
 
-CONFIG_SPIRAM=y
-CONFIG_SPIRAM_MODE_OCT=y
+# No PSRAM by default.
+# CONFIG_SPIRAM=y
+# CONFIG_SPIRAM_MODE_OCT=y
 
 # Disable Watchdog
 # CONFIG_ESP_INT_WDT is not set
@@ -29,3 +34,7 @@ CONFIG_SPIRAM_MODE_OCT=y
 # Enable Compiler Optimization
 CONFIG_COMPILER_OPTIMIZATION_PERF=y
 CONFIG_COMPILER_OPTIMIZATION_ASSERTIONS_DISABLE=y
+
+# Optimize internal SRAM utilization.
+# Allocate WiFi TX buffer dynamically to reduce max RAM usage.
+CONFIG_ESP_WIFI_DYNAMIC_TX_BUFFER=y

src/webrtc.cpp

@@ -59,10 +59,20 @@ static void oai_onconnectionstatechange_task(PeerConnectionState state,
 #endif
   } else if (state == PEER_CONNECTION_CONNECTED) {
 #ifndef LINUX_BUILD
-    StackType_t *stack_memory = (StackType_t *)heap_caps_malloc(
-        20000 * sizeof(StackType_t), MALLOC_CAP_SPIRAM);
-    xTaskCreateStaticPinnedToCore(oai_send_audio_task, "audio_publisher", 20000,
-                                  NULL, 7, stack_memory, &task_buffer, 0);
+    constexpr size_t stack_size = 20000;
+    // Allocate the stack memory from the PSRAM if available. Otherwise,
+    // allocate from the internal memory.
+    StackType_t *stack_memory = (StackType_t *)heap_caps_malloc_prefer(
+        stack_size * sizeof(StackType_t), 2,
+        MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT,
+        MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT);
+    if (stack_memory == nullptr) {
+      ESP_LOGE(LOG_TAG, "Failed to allocate stack memory for audio publisher.");
+      esp_restart();
+    }
+    xTaskCreateStaticPinnedToCore(oai_send_audio_task, "audio_publisher",
+                                  stack_size, NULL, 7, stack_memory,
+                                  &task_buffer, 0);
 #endif
   }
 }