zephyr/include/flash.h

284 lines
8.5 KiB
C

/*
* Copyright (c) 2017 Nordic Semiconductor ASA
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief Public API for FLASH drivers
*/
#ifndef __FLASH_H__
#define __FLASH_H__
/**
* @brief FLASH Interface
* @defgroup flash_interface FLASH Interface
* @ingroup io_interfaces
* @{
*/
#include <zephyr/types.h>
#include <stddef.h>
#include <sys/types.h>
#include <device.h>
#ifdef __cplusplus
extern "C" {
#endif
#if defined(CONFIG_FLASH_PAGE_LAYOUT)
struct flash_pages_layout {
size_t pages_count; /* count of pages sequence of the same size */
size_t pages_size;
};
#endif /* CONFIG_FLASH_PAGE_LAYOUT */
typedef int (*flash_api_read)(struct device *dev, off_t offset, void *data,
size_t len);
typedef int (*flash_api_write)(struct device *dev, off_t offset,
const void *data, size_t len);
typedef int (*flash_api_erase)(struct device *dev, off_t offset, size_t size);
typedef int (*flash_api_write_protection)(struct device *dev, bool enable);
#if defined(CONFIG_FLASH_PAGE_LAYOUT)
/**
* @brief Retrieve a flash device's layout.
*
* A flash device layout is a run-length encoded description of the
* pages on the device. (Here, "page" means the smallest erasable
* area on the flash device.)
*
* For flash memories which have uniform page sizes, this routine
* returns an array of length 1, which specifies the page size and
* number of pages in the memory.
*
* Layouts for flash memories with nonuniform page sizes will be
* returned as an array with multiple elements, each of which
* describes a group of pages that all have the same size. In this
* case, the sequence of array elements specifies the order in which
* these groups occur on the device.
*
* @param dev Flash device whose layout to retrieve.
* @param layout The flash layout will be returned in this argument.
* @param layout_size The number of elements in the returned layout.
*/
typedef void (*flash_api_pages_layout)(struct device *dev,
const struct flash_pages_layout **layout,
size_t *layout_size);
#endif /* CONFIG_FLASH_PAGE_LAYOUT */
struct flash_driver_api {
flash_api_read read;
flash_api_write write;
flash_api_erase erase;
flash_api_write_protection write_protection;
#if defined(CONFIG_FLASH_PAGE_LAYOUT)
flash_api_pages_layout page_layout;
#endif /* CONFIG_FLASH_PAGE_LAYOUT */
const size_t write_block_size;
};
/**
* @brief Read data from flash
*
* @param dev : flash dev
* @param offset : Offset (byte aligned) to read
* @param data : Buffer to store read data
* @param len : Number of bytes to read.
*
* @return 0 on success, negative errno code on fail.
*/
__syscall int flash_read(struct device *dev, off_t offset, void *data,
size_t len);
static inline int _impl_flash_read(struct device *dev, off_t offset, void *data,
size_t len)
{
const struct flash_driver_api *api = dev->driver_api;
return api->read(dev, offset, data, len);
}
/**
* @brief Write buffer into flash memory.
*
* Prior to the invocation of this API, the flash_write_protection_set needs
* to be called first to disable the write protection.
*
* @param dev : flash device
* @param offset : starting offset for the write
* @param data : data to write
* @param len : Number of bytes to write
*
* @return 0 on success, negative errno code on fail.
*/
__syscall int flash_write(struct device *dev, off_t offset, const void *data,
size_t len);
static inline int _impl_flash_write(struct device *dev, off_t offset,
const void *data, size_t len)
{
const struct flash_driver_api *api = dev->driver_api;
return api->write(dev, offset, data, len);
}
/**
* @brief Erase part or all of a flash memory
*
* Acceptable values of erase size and offset are subject to
* hardware-specific multiples of page size and offset. Please check
* the API implemented by the underlying sub driver, for example by
* using flash_get_page_info_by_offs() if that is supported by your
* flash driver.
*
* Prior to the invocation of this API, the flash_write_protection_set needs
* to be called first to disable the write protection.
*
* @param dev : flash device
* @param offset : erase area starting offset
* @param size : size of area to be erased
*
* @return 0 on success, negative errno code on fail.
*
* @see flash_get_page_info_by_offs()
* @see flash_get_page_info_by_idx()
*/
__syscall int flash_erase(struct device *dev, off_t offset, size_t size);
static inline int _impl_flash_erase(struct device *dev, off_t offset,
size_t size)
{
const struct flash_driver_api *api = dev->driver_api;
return api->erase(dev, offset, size);
}
/**
* @brief Enable or disable write protection for a flash memory
*
* This API is required to be called before the invocation of write or erase
* API. Please note that on some flash components, the write protection is
* automatically turned on again by the device after the completion of each
* write or erase calls. Therefore, on those flash parts, write protection needs
* to be disabled before each invocation of the write or erase API. Please refer
* to the sub-driver API or the data sheet of the flash component to get details
* on the write protection behavior.
*
* @param dev : flash device
* @param enable : enable or disable flash write protection
*
* @return 0 on success, negative errno code on fail.
*/
__syscall int flash_write_protection_set(struct device *dev, bool enable);
static inline int _impl_flash_write_protection_set(struct device *dev,
bool enable)
{
const struct flash_driver_api *api = dev->driver_api;
return api->write_protection(dev, enable);
}
struct flash_pages_info {
off_t start_offset; /* offset from the base of flash address */
size_t size;
u32_t index;
};
#if defined(CONFIG_FLASH_PAGE_LAYOUT)
/**
* @brief Get the size and start offset of flash page at certain flash offset.
*
* @param dev flash device
* @param offset Offset within the page
* @param info Page Info structure to be filled
*
* @return 0 on success, -EINVAL if page of the offset doesn't exist.
*/
__syscall int flash_get_page_info_by_offs(struct device *dev, off_t offset,
struct flash_pages_info *info);
/**
* @brief Get the size and start offset of flash page of certain index.
*
* @param dev flash device
* @param page_index Index of the page. Index are counted from 0.
* @param info Page Info structure to be filled
*
* @return 0 on success, -EINVAL if page of the index doesn't exist.
*/
__syscall int flash_get_page_info_by_idx(struct device *dev, u32_t page_index,
struct flash_pages_info *info);
/**
* @brief Get the total number of flash pages.
*
* @param dev flash device
*
* @return Number of flash pages.
*/
__syscall size_t flash_get_page_count(struct device *dev);
/**
* @brief Callback type for iterating over flash pages present on a device.
*
* The callback should return true to continue iterating, and false to halt.
*
* @param info Information for current page
* @param data Private data for callback
* @return True to continue iteration, false to halt iteration.
* @see flash_page_foreach()
*/
typedef bool (*flash_page_cb)(const struct flash_pages_info *info, void *data);
/**
* @brief Iterate over all flash pages on a device
*
* This routine iterates over all flash pages on the given device,
* ordered by increasing start offset. For each page, it invokes the
* given callback, passing it the page's information and a private
* data object.
*
* @param dev Device whose pages to iterate over
* @param cb Callback to invoke for each flash page
* @param data Private data for callback function
*/
void flash_page_foreach(struct device *dev, flash_page_cb cb, void *data);
#endif /* CONFIG_FLASH_PAGE_LAYOUT */
/**
* @brief Get the minimum write block size supported by the driver
*
* The write block size supported by the driver might differ from the write
* block size of memory used because the driver might implements write-modify
* algorithm.
*
* @param dev flash device
*
* @return write block size in bytes.
*/
__syscall size_t flash_get_write_block_size(struct device *dev);
static inline size_t _impl_flash_get_write_block_size(struct device *dev)
{
const struct flash_driver_api *api = dev->driver_api;
return api->write_block_size;
}
#ifdef __cplusplus
}
#endif
/**
* @}
*/
#include <syscalls/flash.h>
#endif /* _FLASH_H_ */