subsys: storage: Add flash_map abstraction module

Introduce flas_map module is abstraction over flash memory and its
driver for using flash memories along with description of
available flash areas.
Module provides simple API for write/read/erase and so one.

Signed-off-by: Andrzej Puzdrowski <[email protected]>

include/flash_map.h

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2017 Nordic Semiconductor ASA
+ * Copyright (c) 2015 Runtime Inc
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef __FLASH_MAP_H__
+#define __FLASH_MAP_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ *
+ * Provides abstraction of flash regions for type of use.
+ * I.e. dude where's my image?
+ *
+ * System will contain a map which contains flash areas. Every
+ * region will contain flash identifier, offset within flash and length.
+ *
+ * 1. This system map could be in a file within filesystem (Initializer
+ * must know/figure out where the filesystem is at).
+ * 2. Map could be at fixed location for project (compiled to code)
+ * 3. Map could be at specific place in flash (put in place at mfg time).
+ *
+ * Note that the map you use must be valid for BSP it's for,
+ * match the linker scripts when platform executes from flash,
+ * and match the target offset specified in download script.
+ */
+#include <zephyr/types.h>
+#include <stddef.h>
+#include <sys/types.h>
+
+#define SOC_FLASH_0_ID 0	/* device_id for SoC flash memory driver */
+#define SPI_FLASH_0_ID 1	/* device_id for external SPI flash driver */
+
+struct flash_area {
+	u8_t fa_id;
+	u8_t fa_device_id;
+	u16_t pad16;
+	off_t fa_off;
+	size_t fa_size;
+};
+
+struct flash_sector {
+	off_t fs_off;
+	size_t fs_size;
+};
+
+/*
+ * Initializes flash map. Memory will be referenced by flash_map code
+ * from this on.
+ */
+void flash_map_init(void);
+
+/*
+ * Start using flash area.
+ */
+int flash_area_open(u8_t id, const struct flash_area **fa);
+
+void flash_area_close(const struct flash_area *fa);
+
+/*
+ * Read/write/erase. Offset is relative from beginning of flash area.
+ */
+int flash_area_read(const struct flash_area *fa, off_t off, void *dst,
+		    size_t len);
+int flash_area_write(const struct flash_area *fa, off_t off, const void *src,
+		     size_t len);
+int flash_area_erase(const struct flash_area *fa, off_t off, size_t len);
+/* int flash_area_is_empty(const struct flash_area *, bool *); */
+
+/*
+ * Alignment restriction for flash writes.
+ */
+u8_t flash_area_align(const struct flash_area *fa);
+
+/*
+ * Given flash area ID, return info about sectors within the area.
+ */
+int flash_area_get_sectors(int fa_id, uint32_t *count,
+			   struct flash_sector *sectors);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __FLASH_MAP_H__ */

subsys/CMakeLists.txt

@@ -10,3 +10,4 @@ add_subdirectory_ifdef(CONFIG_MCUBOOT_IMG_MANAGER  dfu)
 add_subdirectory_ifdef(CONFIG_NET_BUF              net)
 add_subdirectory_ifdef(CONFIG_USB                  usb)
 add_subdirectory(random)
+add_subdirectory(storage)

subsys/Kconfig

@@ -28,3 +28,5 @@ source "subsys/usb/Kconfig"
 source "subsys/dfu/Kconfig"
 
 source "subsys/random/Kconfig"
+
+source "subsys/storage/Kconfig"

subsys/storage/CMakeLists.txt

@@ -0,0 +1 @@
+add_subdirectory_ifdef(CONFIG_FLASH_MAP  flash_map)

subsys/storage/Kconfig

@@ -0,0 +1,13 @@
+# Kconfig - Subsystem configuration options
+#
+# Copyright (c) 2018 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+
+menu "Storage"
+
+source "subsys/storage/flash_map/Kconfig"
+
+endmenu

subsys/storage/flash_map/CMakeLists.txt

@@ -0,0 +1,3 @@
+zephyr_sources(flash_map.c)
+zephyr_sources_ifndef(CONFIG_FLASH_MAP_CUSTOM flash_map_default.c)
+

subsys/storage/flash_map/Kconfig

@@ -0,0 +1,28 @@
+# Kconfig - Flash map abstraction module
+#
+# Copyright (c) 2017 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+#
+# Flash map
+#
+
+menuconfig FLASH_MAP
+	bool
+	prompt "Flash map abstraction module"
+	default n
+	depends on FLASH
+	help
+	  Enable support of flash map abstraction.
+
+config FLASH_MAP_CUSTOM
+	bool
+	prompt "Custom flash map description"
+	default n
+	depends on FLASH_MAP
+	help
+	  This option enables custom flash map description.
+	  User must provide such a description in place of default on
+	  if had enabled this option.