tests: nvmem: Add flash testcase

Add an overlay/config to test the NVMEM subsystem with a flash driver.

Signed-off-by: Pieter De Gendt <[email protected]>

Author: pdgendt

tests/subsys/nvmem/api/CMakeLists.txt

@@ -3,6 +3,6 @@
 
 cmake_minimum_required(VERSION 3.20.0)
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
-project(nvmem_eeprom)
+project(nvmem_api)
 
 target_sources(app PRIVATE src/main.c)

tests/subsys/nvmem/api/flash.overlay

@@ -0,0 +1,35 @@
+/**
+ * Copyright (c) 2025, Basalte bv
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	aliases {
+		nvmem0 = &flashcontroller0;
+	};
+
+	test_consumer0: test-consumer0 {
+		compatible = "vnd,nvmem-consumer";
+		nvmem-cells = <&cell0>, <&cell10>;
+		nvmem-cell-names = "cell0", "cell10";
+	};
+};
+
+&flashcontroller0 {
+	nvmem-layout {
+		compatible = "fixed-layout";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		cell0: cell@0 {
+			reg = <0x0 0x10>;
+			#nvmem-cell-cells = <0>;
+		};
+
+		cell10: cell@10 {
+			reg = <0x10 0x10>;
+			read-only;
+			#nvmem-cell-cells = <0>;
+		};
+	};
+};

tests/subsys/nvmem/api/testcase.yaml

@@ -11,3 +11,9 @@ tests:
       - CONFIG_EEPROM=y
     extra_dtc_overlay_files:
       - eeprom.overlay
+  nvmem.api.flash:
+    extra_configs:
+      - CONFIG_FLASH=y
+      - CONFIG_NVMEM_FLASH_WRITE=y
+    extra_dtc_overlay_files:
+      - flash.overlay