boards: nxp: imx95_evk: add M7 DDR board variant

Add DDR variant of the i.MX95 EVK board (M7 core). Using this
variant, one can run Zephyr from DDR instead of ITCM/DTCM
as it's the case for the M7 "base" board.

Signed-off-by: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>

boards/nxp/imx95_evk/Kconfig.imx95_evk

@@ -2,6 +2,6 @@
 # SPDX-License-Identifier: Apache-2.0
 
 config BOARD_IMX95_EVK
-	select SOC_MIMX9596_M7 if BOARD_IMX95_EVK_MIMX9596_M7
+	select SOC_MIMX9596_M7 if BOARD_IMX95_EVK_MIMX9596_M7 || BOARD_IMX95_EVK_MIMX9596_M7_DDR
 	select SOC_MIMX9596_A55 if BOARD_IMX95_EVK_MIMX9596_A55 || BOARD_IMX95_EVK_MIMX9596_A55_SMP
 	select SOC_PART_NUMBER_MIMX9596AVZXN

boards/nxp/imx95_evk/board.yml

@@ -6,3 +6,5 @@ board:
     variants:
     - name: smp
       cpucluster: a55
+    - name: ddr
+      cpucluster: m7

boards/nxp/imx95_evk/doc/index.rst

@@ -224,26 +224,46 @@ multiple elements required, like ELE+V2X firmware, System Manager, TCM OEI, Cort
 image and so on.
 
 The steps making flash.bin and programming should refer to ``Getting Started with
-MCUXpresso SDK for IMX95LPD5EVK-19.pdf`` in i.MX95 `MCUX SDK release`_.
+MCUXpresso SDK for IMX95LPD5EVK-19.pdf`` in i.MX95 `MCUX SDK release`_. Note that
+for the DDR variant, one should use the Makefile targets containing the ``ddr`` keyword.
 
 See ``4.2 Run an example application``, just rename ``zephyr.bin`` to ``m7_image.bin``
 to make flash.bin and program to SD/eMMC.
 
-Here is an example for the :zephyr:code-sample:`hello_world` application.
+Zephyr supports two M7-based i.MX95 boards: ``imx95_evk/mimx9596/m7`` and
+``imx95_evk/mimx9596/m7/ddr``. The main difference between them is the memory
+used. ``imx95_evk/mimx9596/m7`` uses TCM (ITCM for code and, generally, read-only
+data and DTCM for R/W data), while ``imx95_evk/mimx9596/m7/ddr`` uses DDR.
+
+1. Building the :zephyr:code-sample:`hello_world` application for the TCM-based board
 
 .. zephyr-app-commands::
    :zephyr-app: samples/hello_world
    :board: imx95_evk/mimx9596/m7
    :goals: build
 
-After making flash.bin and program to SD/eMMC, open a serial terminal, reset the board,
-and you should see the following message in the terminal:
+2. Building the :zephyr:code-sample:`hello_world` application for the DDR-based board
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/hello_world
+   :board: imx95_evk/mimx9596/m7/ddr
+   :goals: build
+
+After making flash.bin and program to SD/eMMC, open a serial terminal, and reset the
+board. For the ``imx95_evk/mimx9596/m7`` board you should see something like:
 
 .. code-block:: console
 
    *** Booting Zephyr OS build v3.6.0-4569-g483c01ca11a7 ***
    Hello World! imx95_evk/mimx9596/m7
 
+while, for the ``imx95_evk/mimx9596/m7/ddr`` board, you should get the following output:
+
+.. code-block:: console
+
+   *** Booting Zephyr OS build v3.6.0-4569-g483c01ca11a7 ***
+   Hello World! imx95_evk/mimx9596/m7/ddr
+
 .. _System Control and Management Interface (SCMI):
    https://developer.arm.com/documentation/den0056/latest/
 

boards/nxp/imx95_evk/imx95_evk_mimx9596_m7_ddr.dts

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2024 NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/dts-v1/;
+
+#include "imx95_evk_mimx9596_m7.dts"
+
+/ {
+	model = "NXP i.MX95 EVK board DDR variant";
+
+	chosen {
+		zephyr,sram = &ddr;
+		/delete-property/ zephyr,flash;
+	};
+
+	ddr: memory@80000000 {
+		device_type = "memory";
+		reg = <0x80000000 DT_SIZE_M(4)>;
+	};
+};

boards/nxp/imx95_evk/imx95_evk_mimx9596_m7_ddr.yaml

@@ -0,0 +1,18 @@
+#
+# Copyright 2024 NXP
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+identifier: imx95_evk/mimx9596/m7/ddr
+name: NXP i.MX95 EVK DDR variant
+type: mcu
+arch: arm
+ram: 256
+toolchain:
+  - zephyr
+  - gnuarmemb
+  - xtools
+supported:
+  - uart
+vendor: nxp

boards/nxp/imx95_evk/imx95_evk_mimx9596_m7_ddr_defconfig

@@ -0,0 +1,22 @@
+#
+# Copyright 2024 NXP
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+# clock-related configurations
+CONFIG_CLOCK_CONTROL=y
+
+# serial interface-related configurations
+CONFIG_SERIAL=y
+CONFIG_UART_INTERRUPT_DRIVEN=y
+CONFIG_UART_CONSOLE=y
+CONFIG_CONSOLE=y
+
+# SCMI-related configurations
+CONFIG_MBOX=y
+CONFIG_MBOX_INIT_PRIORITY=0
+CONFIG_ARM_SCMI=y
+
+# kernel-related configurations
+CONFIG_XIP=n