esp32/boards/GENERIC_UNICORE: Add board definition for unicore chips.

Tested to work on an ESP32-MINI-1, which is a single core ESP32-U4DWH.

Signed-off-by: Clayton Cronk <awesomecronk@gmail.com>

ports/esp32/boards/GENERIC_UNICORE/board.json

@@ -0,0 +1,19 @@
+{
+    "deploy": [
+        "../deploy.md"
+    ],
+    "docs": "",
+    "features": [
+        "BLE",
+        "WiFi"
+    ],
+    "id": "esp32-unicore",
+    "images": [
+        "generic_unicore.jpg"
+    ],
+    "mcu": "esp32",
+    "product": "ESP32 Unicore",
+    "thumbnail": "",
+    "url": "https://www.espressif.com/en/products/modules",
+    "vendor": "Espressif"
+}

ports/esp32/boards/GENERIC_UNICORE/board.md

@@ -0,0 +1 @@
+The following files are daily firmware for single-core ESP32-based boards without external SPIRAM.

ports/esp32/boards/GENERIC_UNICORE/mpconfigboard.cmake

@@ -0,0 +1,5 @@
+set(SDKCONFIG_DEFAULTS
+    boards/sdkconfig.base
+    boards/sdkconfig.ble
+    boards/GENERIC_UNICORE/sdkconfig.board
+)

ports/esp32/boards/GENERIC_UNICORE/mpconfigboard.h

@@ -0,0 +1,2 @@
+#define MICROPY_HW_BOARD_NAME "ESP32 Unicore module"
+#define MICROPY_HW_MCU_NAME "ESP32-UNICORE"

ports/esp32/boards/GENERIC_UNICORE/sdkconfig.board

@@ -0,0 +1 @@
+CONFIG_FREERTOS_UNICORE=y

ports/esp32/mphalport.h

@@ -44,7 +44,9 @@
 // and avoid the Wifi/BLE timing problems on the same core.
 // Best effort here to remain backwards compatible in rare version edge cases...
 // See https://github.com/micropython/micropython/issues/5489 for history
-#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(4, 2, 0)
+#if CONFIG_FREERTOS_UNICORE
+#define MP_TASK_COREID (0)
+#elif ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(4, 2, 0)
 #define MP_TASK_COREID (1)
 #else
 #define MP_TASK_COREID (0)