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Public Member Functions | Static Public Member Functions
BlockDevice Class Referenceabstract

A hardware device capable of writing and reading blocks. More...

#include <BlockDevice.h>

Inheritance diagram for BlockDevice:
DataFlashBlockDevice FlashIAPBlockDevice BufferedBlockDevice ChainingBlockDevice ExhaustibleBlockDevice FlashSimBlockDevice HeapBlockDevice MBRBlockDevice ObservingBlockDevice ProfilingBlockDevice ReadOnlyBlockDevice SlicingBlockDevice QSPIFBlockDevice SDBlockDevice SPIFBlockDevice SPIFReducedBlockDevice

Public Member Functions

virtual ~BlockDevice ()
 Lifetime of a block device. More...
 
virtual int init ()=0
 Initialize a block device. More...
 
virtual int deinit ()=0
 Deinitialize a block device. More...
 
virtual int sync ()
 Ensure data on storage is in sync with the driver. More...
 
virtual int read (void *buffer, bd_addr_t addr, bd_size_t size)=0
 Read blocks from a block device. More...
 
virtual int program (const void *buffer, bd_addr_t addr, bd_size_t size)=0
 Program blocks to a block device. More...
 
virtual int erase (bd_addr_t addr, bd_size_t size)
 Erase blocks on a block device. More...
 
virtual int trim (bd_addr_t addr, bd_size_t size)
 Mark blocks as no longer in use. More...
 
virtual bd_size_t get_read_size () const =0
 Get the size of a readable block. More...
 
virtual bd_size_t get_program_size () const =0
 Get the size of a programmable block. More...
 
virtual bd_size_t get_erase_size () const
 Get the size of an erasable block. More...
 
virtual bd_size_t get_erase_size (bd_addr_t addr) const
 Get the size of an erasable block given address. More...
 
virtual int get_erase_value () const
 Get the value of storage when erased. More...
 
virtual bd_size_t size () const =0
 Get the total size of the underlying device. More...
 
bool is_valid_read (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block read validity. More...
 
bool is_valid_program (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block program validity. More...
 
bool is_valid_erase (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block erase validity. More...
 
virtual const char * get_type () const =0
 Get the BlockDevice class type. More...
 

Static Public Member Functions

static BlockDeviceget_default_instance ()
 Return the default block device. More...
 

Detailed Description

A hardware device capable of writing and reading blocks.

Definition at line 47 of file BlockDevice.h.

Constructor & Destructor Documentation

virtual ~BlockDevice ( )
virtual

Lifetime of a block device.

Definition at line 64 of file BlockDevice.h.

Member Function Documentation

virtual int deinit ( )
pure virtual
virtual int erase ( bd_addr_t  addr,
bd_size_t  size 
)
virtual

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

Parameters
addrAddress of block to begin erasing
sizeSize to erase in bytes, must be a multiple of the erase block size
Returns
0 on success or a negative error code on failure

Reimplemented in QSPIFBlockDevice, SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, DataFlashBlockDevice, HeapBlockDevice, ExhaustibleBlockDevice, SPIFReducedBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ObservingBlockDevice, ProfilingBlockDevice, BufferedBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

Definition at line 120 of file BlockDevice.h.

static BlockDevice* get_default_instance ( )
static

Return the default block device.

Returns the default block device based on the configuration JSON. Use the components in target.json or application config to change the default block device.

An application can override all target settings by implementing BlockDevice::get_default_instance() - the default definition is weak, and calls get_target_default_instance().

virtual bd_size_t get_erase_size ( ) const
virtual

Get the size of an erasable block.

Returns
Size of an erasable block in bytes
Note
Must be a multiple of the program size

Reimplemented in QSPIFBlockDevice, SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, DataFlashBlockDevice, HeapBlockDevice, SPIFReducedBlockDevice, ExhaustibleBlockDevice, BufferedBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ProfilingBlockDevice, ObservingBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

Definition at line 159 of file BlockDevice.h.

virtual bd_size_t get_erase_size ( bd_addr_t  addr) const
virtual

Get the size of an erasable block given address.

Parameters
addrAddress within the erasable block
Returns
Size of an erasable block in bytes
Note
Must be a multiple of the program size

Reimplemented in MBRBlockDevice, ChainingBlockDevice, DataFlashBlockDevice, HeapBlockDevice, SPIFReducedBlockDevice, ExhaustibleBlockDevice, BufferedBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ProfilingBlockDevice, ObservingBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

Definition at line 170 of file BlockDevice.h.

virtual int get_erase_value ( ) const
virtual

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.

Returns
The value of storage when erased, or -1 if you can't rely on the value of the erased storage

Reimplemented in QSPIFBlockDevice, SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, SPIFReducedBlockDevice, ExhaustibleBlockDevice, BufferedBlockDevice, SlicingBlockDevice, ProfilingBlockDevice, ObservingBlockDevice, FlashSimBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

Definition at line 184 of file BlockDevice.h.

virtual bd_size_t get_program_size ( ) const
pure virtual
virtual bd_size_t get_read_size ( ) const
pure virtual
virtual const char* get_type ( ) const
pure virtual
virtual int init ( )
pure virtual
bool is_valid_erase ( bd_addr_t  addr,
bd_size_t  size 
) const

Convenience function for checking block erase validity.

Parameters
addrAddress of block to begin erasing
sizeSize to erase in bytes
Returns
True if erase is valid for underlying block device

Definition at line 229 of file BlockDevice.h.

bool is_valid_program ( bd_addr_t  addr,
bd_size_t  size 
) const

Convenience function for checking block program validity.

Parameters
addrAddress of block to begin writing to
sizeSize to write in bytes
Returns
True if program is valid for underlying block device

Definition at line 215 of file BlockDevice.h.

bool is_valid_read ( bd_addr_t  addr,
bd_size_t  size 
) const

Convenience function for checking block read validity.

Parameters
addrAddress of block to begin reading from
sizeSize to read in bytes
Returns
True if read is valid for underlying block device

Definition at line 201 of file BlockDevice.h.

virtual int program ( const void *  buffer,
bd_addr_t  addr,
bd_size_t  size 
)
pure virtual

Program blocks to a block device.

The blocks must have been erased prior to being programmed

If a failure occurs, it is not possible to determine how many bytes succeeded

Parameters
bufferBuffer of data to write to blocks
addrAddress of block to begin writing to
sizeSize to write in bytes, must be a multiple of the program block size
Returns
0 on success or a negative error code on failure

Implemented in QSPIFBlockDevice, SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, DataFlashBlockDevice, HeapBlockDevice, SPIFReducedBlockDevice, ExhaustibleBlockDevice, SDBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ObservingBlockDevice, ProfilingBlockDevice, BufferedBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

virtual int read ( void *  buffer,
bd_addr_t  addr,
bd_size_t  size 
)
pure virtual

Read blocks from a block device.

If a failure occurs, it is not possible to determine how many bytes succeeded

Parameters
bufferBuffer to write blocks to
addrAddress of block to begin reading from
sizeSize to read in bytes, must be a multiple of the read block size
Returns
0 on success or a negative error code on failure

Implemented in QSPIFBlockDevice, SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, DataFlashBlockDevice, HeapBlockDevice, SPIFReducedBlockDevice, ExhaustibleBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, SDBlockDevice, ObservingBlockDevice, ProfilingBlockDevice, BufferedBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

virtual bd_size_t size ( ) const
pure virtual
virtual int sync ( )
virtual

Ensure data on storage is in sync with the driver.

Returns
0 on success or a negative error code on failure

Reimplemented in MBRBlockDevice, ChainingBlockDevice, ExhaustibleBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ObservingBlockDevice, ProfilingBlockDevice, BufferedBlockDevice, and ReadOnlyBlockDevice.

Definition at line 82 of file BlockDevice.h.

virtual int trim ( bd_addr_t  addr,
bd_size_t  size 
)
virtual

Mark blocks as no longer in use.

This function provides a hint to the underlying block device that a region of blocks is no longer in use and may be erased without side effects. Erase must still be called before programming, but trimming allows flash-translation-layers to schedule erases when the device is not busy.

Parameters
addrAddress of block to mark as unused
sizeSize to mark as unused in bytes, must be a multiple of the erase block size
Returns
0 on success or a negative error code on failure

Reimplemented in SDBlockDevice, and BufferedBlockDevice.

Definition at line 136 of file BlockDevice.h.

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