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Kevin Thomas 334f511256 Drivers
2026-03-22 20:39:16 -04:00

69 lines
2.7 KiB
C

/**
* @file flash.h
* @brief Header for on-chip flash read/write driver (XIP memory-mapped)
* @author Kevin Thomas
* @date 2025
*
* MIT License
*
* Copyright (c) 2025 Kevin Thomas
*
* 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 FLASH_H
#define FLASH_H
#include <stdint.h>
#include <stdbool.h>
#define FLASH_DRIVER_SIZE_BYTES (4 * 1024 * 1024)
#define FLASH_DRIVER_SECTOR_SIZE 4096
#define FLASH_DRIVER_PAGE_SIZE 256
/**
* @brief Erase one 4096-byte sector and write data to on-chip flash
*
* The target address must be aligned to a 4096-byte sector boundary.
* The function disables interrupts, erases the containing sector,
* programs up to @p len bytes from @p data, and re-enables interrupts. The
* write length must be a multiple of FLASH_DRIVER_PAGE_SIZE (256 bytes);
* pad with 0xFF if necessary.
*
* @param flash_offset Byte offset from the start of flash (must be sector-aligned)
* @param data Pointer to the data buffer to write
* @param len Number of bytes to write (multiple of FLASH_DRIVER_PAGE_SIZE)
*/
void flash_driver_write(uint32_t flash_offset, const uint8_t *data, uint32_t len);
/**
* @brief Read bytes from on-chip flash via the XIP memory map
*
* Flash is memory-mapped starting at XIP_BASE (0x10000000). This function
* copies @p len bytes beginning at @p flash_offset into @p out using the
* XIP read path, which is always available without erasing.
*
* @param flash_offset Byte offset from the start of flash
* @param out Pointer to the destination buffer (must be @p len bytes)
* @param len Number of bytes to read
*/
void flash_driver_read(uint32_t flash_offset, uint8_t *out, uint32_t len);
#endif // FLASH_H