/* mbed Microcontroller Library
* Copyright (c) 2017-2020 ARM Limited
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef MBED_CHAINING_BLOCK_DEVICE_H
#define MBED_CHAINING_BLOCK_DEVICE_H
#include "BlockDevice.h"
#include "platform/mbed_assert.h"
#include <stdlib.h>
namespace mbed {
/** \addtogroup storage-blockdevice */
/** @{*/
/** Block device for chaining multiple block devices
* with the similar block sizes at sequential addresses
*
* @code
* #include "mbed.h"
* #include "HeapBlockDevice.h"
* #include "ChainingBlockDevice.h"
*
* // Create two smaller block devices with
* // 64 and 32 blocks of size 512 bytes
* HeapBlockDevice mem1(64*512, 512);
* HeapBlockDevice mem2(32*512, 512);
*
* // Create a block device backed by mem1 and mem2
* // contains 96 blocks of size 512 bytes
* BlockDevice *bds[] = {&mem1, &mem2};
* ChainingBlockDevice chainmem(bds);
* @endcode
*/
class ChainingBlockDevice : public BlockDevice {
public:
/** Lifetime of the memory block device
*
* @param bds Array of block devices to chain with sequential block addresses
* @param bd_count Number of block devices to chain
* @note All block devices must have the same block size
*/
ChainingBlockDevice(BlockDevice **bds, size_t bd_count);
/** Lifetime of the memory block device
*
* @param bds Array of block devices to chain with sequential block addresses
* @note All block devices must have the same block size
*/
template <size_t Size>
ChainingBlockDevice(BlockDevice * (&bds)[Size])
: _bds(bds), _bd_count(sizeof(bds) / sizeof(bds[0]))
, _read_size(0), _program_size(0), _erase_size(0), _size(0), _init_ref_count(0)
{
}
/** Lifetime of the memory block device
*
*/
virtual ~ChainingBlockDevice() {}
/** Initialize a block device
*
* @return 0 on success or a negative error code on failure
*/
virtual int init();
/** Deinitialize a block device
*
* @return 0 on success or a negative error code on failure
*/
virtual int deinit();
/** Ensure data on storage is in sync with the driver
*
* @return 0 on success or a negative error code on failure
*/
virtual int sync();
/** Read blocks from a block device
*
* @param buffer Buffer to write blocks to
* @param addr Address of block to begin reading from
* @param size Size to read in bytes, must be a multiple of read block size
* @return 0 on success, negative error code on failure
*/
virtual int read(void *buffer, bd_addr_t addr, bd_size_t size);
/** Program blocks to a block device
*
* The blocks must have been erased prior to being programmed
*
* @param buffer Buffer of data to write to blocks
* @param addr Address of block to begin writing to
* @param size Size to write in bytes, must be a multiple of program block size
* @return 0 on success, negative error code on failure
*/
virtual int program(const void *buffer, bd_addr_t addr, bd_size_t size);
/** Erase blocks on a block device
*
* The state of an erased block is undefined until it has been programmed,
* unless get_erase_value returns a non-negative byte value
*
* @param addr Address of block to begin erasing
* @param size Size to erase in bytes, must be a multiple of erase block size
* @return 0 on success, negative error code on failure
*/
virtual int erase(bd_addr_t addr, bd_size_t size);
/** Get the size of a readable block
*
* @return Size of a readable block in bytes
*/
virtual bd_size_t get_read_size() const;
/** Get the size of a programmable block
*
* @return Size of a programmable block in bytes
* @note Must be a multiple of the read size
*/
virtual bd_size_t get_program_size() const;
/** Get the size of an eraseable block
*
* @return Size of an erasable block in bytes
* @note Must be a multiple of the program size
*/
virtual bd_size_t get_erase_size() const;
/** Get the size of an erasable block given address
*
* @param addr Address within the erasable block
* @return Size of an erasable block in bytes
* @note Must be a multiple of the program size
*/
virtual bd_size_t get_erase_size(bd_addr_t addr) const;
/** Get the value of storage when erased
*
* If get_erase_value returns a non-negative byte value, the underlying
* storage is set to that value when erased, and storage containing
* that value can be programmed without another erase.
*
* @return The value of storage when erased, or -1 if you can't
* rely on the value of erased storage
*/
virtual int get_erase_value() const;
/** Get the total size of the underlying device
*
* @return Size of the underlying device in bytes
*/
virtual bd_size_t size() const;
/** Get the BlockDevice class type.
*
* @return A string represent the BlockDevice class type.
*/
virtual const char *get_type() const;
protected:
BlockDevice **_bds;
size_t _bd_count;
bd_size_t _read_size;
bd_size_t _program_size;
bd_size_t _erase_size;
bd_size_t _size;
int _erase_value;
uint32_t _init_ref_count;
bool _is_initialized;
};
/** @}*/
} // namespace mbed
// Added "using" for backwards compatibility
#ifndef MBED_NO_GLOBAL_USING_DIRECTIVE
using mbed::ChainingBlockDevice;
#endif
#endif
