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Diffstat (limited to 'watch-library/shared/watch/watch_storage.h')
| -rw-r--r-- | watch-library/shared/watch/watch_storage.h | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/watch-library/shared/watch/watch_storage.h b/watch-library/shared/watch/watch_storage.h new file mode 100644 index 00000000..6026cbcf --- /dev/null +++ b/watch-library/shared/watch/watch_storage.h @@ -0,0 +1,92 @@ +/* + * MIT License + * + * Copyright (c) 2020 Joey Castillo + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ +#ifndef _WATCH_STORAGE_H_INCLUDED +#define _WATCH_STORAGE_H_INCLUDED +////< @file watch_storage.h + +#include "watch.h" + +#ifndef NVMCTRL_ROW_SIZE +#define NVMCTRL_ROW_SIZE 256 +#endif +#ifndef NVMCTRL_PAGE_SIZE +#define NVMCTRL_PAGE_SIZE 64 +#endif +#ifndef NVMCTRL_RWWEE_PAGES +#define NVMCTRL_RWWEE_PAGES 128 +#endif + +/** @addtogroup storage Flash Storage + * @brief This section covers functions related to the SAM L22's 8 kilobyte EEPROM emulation area. + * @details The SAM L22 inside Sensor Watch has a 256 kilobyte Flash memory array that can be + * programmed with whatever data we want. We use most of it to store the bootloader + * and the application code that runs on your wrist. The bootloader region is read-only, + * and the main application area is only writable by the bootloader (when you drag new + * code onto the WATCHBOOT drive). However! there's also a special 8 kilobyte region + * at the end of the Flash memory called the EEPROM Emulation Area. This EEPROM emulation + * area can be written or erased while the main Flash array is being read. This makes it + * super easy to work with, and useful for storing a small amount of non-volatile data that + * persists across reboots, even when power is lost. + * The functions in this section are very basic, and only cover reading and writing data + * in this area. The region is laid out as 32 rows consisting of 4 pages of 64 bytes. + * 32*4*64 = 8192 bytes. The area can be written one page at a time, but it can only be + * erased one row at a time. You can read at arbitrary word-aligned offsets within a row. + * + * ┌──────────────┬──────────────┬──────────────┬──────────────┐ + * Row 0 │ 64 bytes │ 64 bytes │ 64 bytes │ 64 bytes │ + * ├──────────────┼──────────────┼──────────────┼──────────────┤ + * Row 1 │ 64 bytes │ 64 bytes │ 64 bytes │ 64 bytes │ + * ├──────────────┼──────────────┼──────────────┼──────────────┤ + * ... │ │ │ │ │ + * ├──────────────┼──────────────┼──────────────┼──────────────┤ + * Row 31 │ 64 bytes │ 64 bytes │ 64 bytes │ 64 bytes │ + * └──────────────┴──────────────┴──────────────┴──────────────┘ + */ +/// @{ +/** @brief Reads a range of bytes from the storage area. + * @param row The row you want to read. + * @param offset The offset from the beginning of the row. + * @param buffer A buffer of at least `size` bytes. + * @param size The number of bytes you wish to read. + */ +bool watch_storage_read(uint32_t row, uint32_t offset, uint8_t *buffer, uint32_t size); + +/** @brief Writes bytes to a page in the storage area. Note that the row should already be erased before writing. + * @param row The row containing the page you want to write. + * @param offset The offset from the beginning of the row. Must be a multiple of 64. + * @param buffer The buffer containing the bytes you wish to set. + * @param size The number of bytes you wish to write. + */ +bool watch_storage_write(uint32_t row, uint32_t offset, const uint8_t *buffer, uint32_t size); + +/** @brief Erases a row in the storage area, setting all its bytes to 0xFF. + * @param row The row you want to erase. + */ +bool watch_storage_erase(uint32_t row); + +/** @brief Waits for any pending writes to complete. + */ +bool watch_storage_sync(void); +/// @} +#endif |