boards: arm: nucleo_f746zg: enable backup SRAM

Enable backup SRAM DT node and update documentation.

Signed-off-by: Gerard Marull-Paretas <[email protected]>

Author: gmarull

boards/arm/nucleo_f746zg/doc/index.rst

@@ -93,33 +93,35 @@ Supported Features
 The Zephyr nucleo_f746zg board configuration supports the following hardware
 features:
 
-+-----------+------------+-------------------------------------+
-| Interface | Controller | Driver/Component                    |
-+===========+============+=====================================+
-| NVIC      | on-chip    | nested vector interrupt controller  |
-+-----------+------------+-------------------------------------+
-| UART      | on-chip    | serial port                         |
-+-----------+------------+-------------------------------------+
-| PINMUX    | on-chip    | pinmux                              |
-+-----------+------------+-------------------------------------+
-| GPIO      | on-chip    | gpio                                |
-+-----------+------------+-------------------------------------+
-| ETHERNET  | on-chip    | ethernet                            |
-+-----------+------------+-------------------------------------+
-| USB       | on-chip    | usb_device                          |
-+-----------+------------+-------------------------------------+
-| COUNTER   | on-chip    | rtc                                 |
-+-----------+------------+-------------------------------------+
-| I2C       | on-chip    | i2c                                 |
-+-----------+------------+-------------------------------------+
-| PWM       | on-chip    | pwm                                 |
-+-----------+------------+-------------------------------------+
-| SPI       | on-chip    | spi                                 |
-+-----------+------------+-------------------------------------+
-| WATCHDOG  | on-chip    | independent watchdog                |
-+-----------+------------+-------------------------------------+
-| ADC       | on-chip    | ADC Controller                      |
-+-----------+------------+-------------------------------------+
++-------------+------------+-------------------------------------+
+| Interface   | Controller | Driver/Component                    |
++=============+============+=====================================+
+| NVIC        | on-chip    | nested vector interrupt controller  |
++-------------+------------+-------------------------------------+
+| UART        | on-chip    | serial port                         |
++-------------+------------+-------------------------------------+
+| PINMUX      | on-chip    | pinmux                              |
++-------------+------------+-------------------------------------+
+| GPIO        | on-chip    | gpio                                |
++-------------+------------+-------------------------------------+
+| ETHERNET    | on-chip    | ethernet                            |
++-------------+------------+-------------------------------------+
+| USB         | on-chip    | usb_device                          |
++-------------+------------+-------------------------------------+
+| COUNTER     | on-chip    | rtc                                 |
++-------------+------------+-------------------------------------+
+| I2C         | on-chip    | i2c                                 |
++-------------+------------+-------------------------------------+
+| PWM         | on-chip    | pwm                                 |
++-------------+------------+-------------------------------------+
+| SPI         | on-chip    | spi                                 |
++-------------+------------+-------------------------------------+
+| WATCHDOG    | on-chip    | independent watchdog                |
++-------------+------------+-------------------------------------+
+| ADC         | on-chip    | ADC Controller                      |
++-------------+------------+-------------------------------------+
+| Backup SRAM | on-chip    | Backup SRAM                         |
++-------------+------------+-------------------------------------+
 
 Other hardware features are not yet supported on this Zephyr port.
 
@@ -164,6 +166,11 @@ Serial Port
 Nucleo F746ZG board has 4 UARTs and 4 USARTs. The Zephyr console output is
 assigned to UART3. Default settings are 115200 8N1.
 
+Backup SRAM
+-----------
+
+In order to test backup SRAM you may want to disconnect VBAT from VDD. You can
+do it by removing ``SB156`` jumper on the back side of the board.
 
 Programming and Debugging
 *************************

boards/arm/nucleo_f746zg/nucleo_f746zg.dts

@@ -148,3 +148,7 @@
 		     &eth_txd0_pg13
 		     &eth_txd1_pb13>;
 };
+
+&backup_sram {
+	status = "okay";
+};

boards/arm/nucleo_f746zg/nucleo_f746zg.yaml

@@ -24,3 +24,4 @@ supported:
   - can
   - adc
   - dma
+  - backup_sram