board, hwconfig: Set POWER_EN in early boot

In order to turn the Tonberry device on more reliably even if the power
button is only pressed for a short time, move the setting of POWER_EN
pin to high from the python board_init to the MICROPY_BOARD_STARTUP
macro so that is is started in the C startup code run before the
micropython interpreter is initialized.

Measured time from power on to POWER_EN time was 600-800 ms with the
python board_init, vs. 155 ms for the MICROPY_BOARD_STARTUP.

Signed-off-by: Matthias Blankertz <matthias@blankertz.org>

software/boards/RPI_PICO_W/mpconfigboard.h

@@ -25,3 +25,12 @@ int mp_hal_is_pin_reserved(int n);
 #define MICROPY_HW_PIN_RESERVED(i) mp_hal_is_pin_reserved(i)
 
 #define MICROPY_PY_THREAD (0)
+
+#define TONBERRY_POWER_EN 22
+
+#define MICROPY_BOARD_STARTUP()                \
+    {                                          \
+        gpio_init(TONBERRY_POWER_EN);          \
+        gpio_set_dir(TONBERRY_POWER_EN, true); \
+        gpio_put(TONBERRY_POWER_EN, true);     \
+    }

software/src/hwconfig_Rev1.py

@@ -41,10 +41,8 @@ VBAT_ADC = Pin.board.GP26
 
 
 def board_init():
-    # Keep power turned on
+    # POWER_EN turned on in MICROPY_BOARD_STARTUP
     # TODO: Implement soft power off
-    POWER_EN.init(mode=Pin.OUT)
-    POWER_EN.value(1)
 
     # Set 8 mA drive strength and fast slew rate for SD SPI
     machine.mem32[0x4001c004 + 6*4] = 0x67