aedec74b9a
Added WiFi_Bt CM4 PSA target in mbedos json Added SPE-NSPE mailbox initialization for CM4 SystemInit Made similar to FUTURE_SEQUANA configurations Copied FUTURE_SEQUANA CM0 SPM part for WiFi_Bt smoke test Added CY8CKIT_062_WIFI_BT_M0 and CY8CKIT_062_WIFI_BT_M0_PSA targets Sorted files for new CY8CKIT_062_WIFI_BT_M0 and CY8CKIT_062_WIFI_BT_M0_PSA targets Copied files for CY8CKIT_062_WIFI_BT_M0_PSA from FUTURE_SEQUANA Copied and updated cm0p start files Corrected according to FUTURE_SEQUANA Changes to M0 startup files to have SPM started Fixed implicit declaration warning Commented interrupts enabling according to FUTURE_SEQUANA flow Updated prebuild spm_smore CM0 hex for CM4 target Turned on greentea environment Used special memory region for common CM0/CM4 data Updated prebuild CM0 SPM hex Placed shared memory region for flash operations into SPM shared memory region Updated cyprotection code and configuration Start address of protected regions is set by a defined number from target.json Added masters pcMask configuration Added support for PSA target to WIFI_BT board Enabled resources protection for SPM Aligned RAM usage according to Cypress FlashBoot and CyBootloader alligned protection config Added CYW943012P6EVB_01_M0 target Enlarged heap size, remobed nv_seed Added heap reservation in linker script from mbed-os Removed heap size definition turned on nv_seed config Removed nv_seed macros Enabled protection for PSoC6 CM0 Added PSoC6 CM0 PSA readme Enabled mbed_hal-spm test Enabled nv_seed and removed unneeded ipc config define Added SPDX string to feature_ble cypress target files Removed unneeded supported_toolchains lines for Cypress targets Disabled protection settings Corrected flash initialization for PSoC6 CM0 PSA Changed PSoC6 IPC6 protection for flash Enabled special flash initialization and enabled protection settings Updated and added new prebuild PSoC6 CM0 PSA hex files Disabled HW TRNG and CRC for PSoC6 CM4 PSA target Added missing const to allow types to match Updated PSoC6 WIFI_BT_PSA prebuilt directory Moved PSoC6 shared section usage area definition to begin of ld Added initial ARM_STD linker and startup files for PSoC6 CM0 Added initial IAR linker and startup files for PSoC6 CM0 Added defines to disable some SPM protection settings for PSoC64 Moved Flash function variables into separate memory region Added defines for new Public area definition Updated PSoC6 CM0_PSA hex-files |
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| TESTS/nvstore/functionality | ||
| source | ||
| README.md | ||
| mbed_lib.json | ||
README.md
NVStore
NVStore is a lightweight module that stores data by keys in the internal flash for security purposes.
Description
NVStore provides the ability to store a minimal set of system critical items in the internal flash.
For each item key, the NVStore module provides the ability to set the item data or get it.
Newly added values are added to the end of the existing data, superseding the previous value that was there for the same key.
The NVStore module ensures that power failures don't harm existing data during any operation.
The full interface can be found under nvstore.h.
Flash structure
NVStore uses two Flash areas, active and nonactive. Each area must consist of at least one erasable unit (sector). Data is written to the active area until it becomes full. When it does, garbage collection is invoked. This compacts items from the active area to the nonactive one and switches activity between areas. Each item is kept in an entry containing a header and data, where the header holds the item key, size and CRC.
APIs
- init: Initialize NVStore (also lazily called by get, set, set_once and remove APIs).
- deinit: Deinitialize NVStore.
- get: Get the value of an item, given key.
- set: Set the value of an item, given key and value.
- set_once: Like set, but allows only a one time setting of this item (and disables deleting of this item).
- alloc_key: Allocates a free key (from the keys that are not predefined) to an owner (an owning feature).
- free_all_keys_by_owner: Free all allocated keys, given an owner.
- remove: Remove an item, given key.
- get_item_size: Get the item value size (in bytes).
- set_max_keys: Set maximal value of unique keys. Overriding the default of NVSTORE_MAX_KEYS. This affects RAM consumption, as NVStore consumes 4 bytes per unique key. Reinitializes the module.
Usage
Enabling NVStore and configuring it for your board
NVStore is enabled by default for all devices with the internal flash driver (have "FLASH" in the device_has attribute).
One can disable it by setting its "enabled" attribute to false.
Unless specifically configured by the user, NVStore selects the last two flash sectors as its areas, with the minimum size of 4KBs,
meaning that if the sectors are smaller, few continuous ones will be used for each area.
The user can override this by setting the addresses and sizes of both areas in mbed_lib.json on a per board basis.
In this case, all following four attributes need to be set:
- area_1_address
- area_1_size
- area_2_address
- area_2_size
In addition, the num_keys value should be modified to change the default number of different keys.
Using NVStore
NVStore is a singleton class, meaning that the system can have only a single instance of it. To instantiate NVStore, one needs to call its get_instance member function as following:
NVStore &nvstore = NVStore::get_instance();
After the NVStore instantiation, one can call the init API, but it is not necessary because all NVStore APIs (get, set and so on) perform a "lazy initialization".
Testing NVStore
Run the NVStore functionality test with the mbed command as following:
mbed test -n features-nvstore-tests-nvstore-functionality