doc: nrf-bm: libraries: add bm_storage documentation

doc/nrf-bm/api/api.rst

@@ -84,6 +84,8 @@ Bare Metal Low Power UART with EasyDMA driver
    :inner:
    :members:
 
+.. _api_storage:
+
 Bare Metal Storage library
 ==========================
 

doc/nrf-bm/libraries/bm_storage.rst

@@ -0,0 +1,131 @@
+.. _lib_storage:
+
+Storage Library
+###############
+
+.. contents::
+   :local:
+   :depth: 2
+
+The Storage library provides abstractions for reading, writing, and erasing non-volatile memory (NVM).
+
+Overview
+********
+
+The library supports multiple storage instances, each bound to a specific memory region, and reports operation results through user-defined event handlers.
+Depending on the backend and runtime state, operations may be synchronous or asynchronous.
+
+Configuration
+*************
+
+The library is enabled and configured entirely using the Kconfig system.
+Set the :kconfig:option:`CONFIG_BM_STORAGE` Kconfig option to enable the library.
+
+Select a storage backend by enabling one of the following Kconfig options:
+
+* :kconfig:option:`CONFIG_BM_STORAGE_BACKEND_RRAM` – RRAM backend. The events reported are synchronous.
+* :kconfig:option:`CONFIG_BM_STORAGE_BACKEND_SD` – SoftDevice backend. The events reported are asynchronous.
+
+SoftDevice backend options:
+
+* :kconfig:option:`CONFIG_BM_STORAGE_BACKEND_SD_QUEUE_SIZE` – Queue size for pending operations.
+* :kconfig:option:`CONFIG_BM_STORAGE_BACKEND_SD_MAX_RETRIES` – Maximum retries if the SoftDevice is busy.
+
+Initialization
+==============
+
+Each storage instance is represented by a :c:struct:`bm_storage` structure.
+
+To initialize a storage instance, use the :c:func:`bm_storage_init` function, providing the following information:
+
+* :c:member:`bm_storage.evt_handler` – Event callback.
+* :c:member:`bm_storage.start_addr` and :c:member:`bm_storage.end_addr` – Accessible address range.
+
+You can uninitialize a storage instance with the :c:func:`bm_storage_uninit` function.
+
+Usage
+*****
+
+The following is a list of operations you can perform with this library.
+
+Read
+====
+
+Use the :c:func:`bm_storage_read` function to copy data from NVM into RAM.
+The data length must be a multiple of the backend’s program unit and within the configured region.
+
+.. note::
+
+   The program unit is the smallest block of data that the backend can write in a single operation.
+   Both the destination address and the length must be aligned to this size.
+   The program unit is reported by :c:member:`bm_storage_info.program_unit`.
+
+Write
+=====
+
+Use the :c:func:`bm_storage_write` function to write data to NVM.
+Writes are validated against alignment and range, and completion is reported through :c:member:`bm_storage.evt_handler`.
+
+.. note::
+
+   Writes must be aligned to the backend’s program unit, reported by :c:member:`bm_storage_info.program_unit`.
+   This ensures that both the write address and the write length are correct for the underlying memory technology.
+
+Erase
+=====
+
+Use the :c:func:`bm_storage_erase` function to erase a region in NVM.
+``len`` must be a multiple of the erase unit.
+If not supported by the backend, the call may return ``NRF_ERROR_NOT_SUPPORTED``.
+This means that the backend does not require the region to be erased before another write operation.
+
+.. note::
+
+   The erase unit is the minimum erasable block in NVM.
+   Erase operations must start at an address aligned by the erase unit and use a length that is a multiple of this value.
+   The erase unit is reported by :c:member:`bm_storage_info.erase_unit`.
+
+Busy state
+==========
+
+Use the :c:func:`bm_storage_is_busy` function to check whether a backend is executing an operation.
+
+Events
+======
+
+The following events may be reported to the user callback:
+
+* :c:enum:`BM_STORAGE_EVT_WRITE_RESULT` – Write operation completed.
+* :c:enum:`BM_STORAGE_EVT_ERASE_RESULT` – Erase operation completed.
+
+Each event includes the result code, information about the address range of the associated operation, and whether the operation is synchronous or asynchronous.
+
+Sample
+******
+
+The usage of this library is demonstrated in the :ref:`storage_sample` sample.
+
+Dependencies
+************
+
+* :kconfig:option:`CONFIG_BM_STORAGE_BACKEND_RRAM`:
+
+  This backend requires the following Kconfig options to be disabled:
+
+  * :kconfig:option:`CONFIG_SOFTDEVICE`
+
+* :kconfig:option:`CONFIG_BM_STORAGE_BACKEND_SD`:
+
+  This backend requires the following Kconfig options to be enabled:
+
+  * :kconfig:option:`CONFIG_SOFTDEVICE`
+  * :kconfig:option:`CONFIG_NRF_SDH`
+  * :kconfig:option:`CONFIG_RING_BUFFER`
+
+API documentation
+*****************
+
+| Header file: :file:`include/bm_storage.h`
+| Source files: :file:`lib/bm_storage/`
+
+:ref:`Storage library API reference <api_storage>`

doc/nrf-bm/release_notes/release_notes_changelog.rst

@@ -151,6 +151,7 @@ Documentation
 * Added documentation for the :ref:`lib_ble_queued_writes` library.
 * Added documentation for the :ref:`lib_event_scheduler` library.
 * Added documentation for the :ref:`lib_sensorsim` library.
+* Added documentation for the :ref:`lib_storage` library.
 * Added documentation for the :ref:`lib_ble_queued_writes` library.
 
 Interrupts

include/bm/storage/bm_storage.h

@@ -77,13 +77,21 @@ typedef void (*bm_storage_evt_handler_t)(struct bm_storage_evt *evt);
  * @brief Information about the implementation-specific non-volatile memory.
  */
 struct bm_storage_info {
-	/* Size of a page (in bytes). A page is the smallest unit that can be erased. */
+	/**
+	 * @brief Size of a page (in bytes). A page is the smallest unit that can be erased.
+	 */
 	uint32_t erase_unit;
-	/* Value used by the implementation-specific backend to represent erased memory. */
+	/**
+	 * @brief Value used by the implementation-specific backend to represent erased memory.
+	 */
 	uint32_t erase_value;
-	/* Size of the smallest programmable unit (in bytes). */
+	/**
+	 * @brief Size of the smallest programmable unit (in bytes).
+	 */
 	uint32_t program_unit;
-	/* Specifies if the implementation-specific backend does not need erase. */
+	/**
+	 * @brief Specifies if the implementation-specific backend does not need erase.
+	 */
 	bool no_explicit_erase;
 };
 
@@ -213,6 +221,8 @@ uint32_t bm_storage_write(const struct bm_storage *storage, uint32_t dest, const
  * @brief Erase data in a storage instance.
  *
  * @param[in] storage Storage instance to erase data in.
+ * @param[in] dest Address in non-volatile memory where to erase the data.
+ * @param[in] len Length of the data to be erased (in bytes).
  * @param[in] ctx Pointer to user data, passed to the implementation-specific API function call.
  *                Can be NULL.
  *