/**
* @file
*
* @brief Non-volatile Disk Block Device Implementation
*/
/*
* Copyright (C) 2007 Chris Johns
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
/**
* The Non-volatile disk provides a simple directly mapped disk
* driver with checksums for each. It is designed to provied a
* disk that can survive a restart. Examples are EEPROM devices
* which have byte writeable locations, or a battery backed up
* RAM disk.
*
* The low level driver provides the physical access to the
* hardware.
*/
#if !defined (_RTEMS_NVDISK_H_)
#define _RTEMS_NVDISK_H_
#include <stdint.h>
#include <sys/ioctl.h>
#include <rtems.h>
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/**
* The base name of the nv disks.
*/
#define RTEMS_NVDISK_DEVICE_BASE_NAME "/dev/nvd"
/**
* NV disk specific ioctl request types. To use open the
* device and issue the ioctl call.
*
* @code
* int fd = open ("/dev/nvdisk0", O_WRONLY, 0);
* if (fd < 0)
* {
* printf ("driver open failed: %s\n", strerror (errno));
* exit (1);
* }
* if (ioctl (fd, RTEMS_NVDISK_IOCTL_ERASE_DISK) < 0)
* {
* printf ("driver erase failed: %s\n", strerror (errno));
* exit (1);
* }
* close (fd);
* @endcode
*/
#define RTEMS_NVDISK_IOCTL_ERASE_DISK _IO('B', 128)
#define RTEMS_NVDISK_IOCTL_MONITORING _IO('B', 129)
#define RTEMS_NVDISK_IOCTL_INFO_LEVEL _IO('B', 130)
#define RTEMS_NVDISK_IOCTL_PRINT_STATUS _IO('B', 131)
/**
* NV Disk Monitoring Data allows a user to obtain
* the current status of the disk.
*/
typedef struct rtems_nvdisk_monitor_data
{
uint32_t block_size;
uint32_t block_count;
uint32_t page_count;
uint32_t pages_available;
uint32_t pages_used;
uint32_t info_level;
} rtems_nvdisk_monitor_data;
/**
* Return the number of kilo-bytes.
*/
#define RTEMS_NVDISK_KBYTES(_k) ((_k) * 1024)
/**
* NV Low Level driver handlers.
* Typically this structure is part of a table of handlers in the
* device which is referenced in the nvdisk configuration table.
* The reference is kept in the driver and used all the time to
* manage the nv device, therefore it must always exist.
*/
typedef struct rtems_nvdisk_driver_handlers
{
/**
* Read data from the device into the buffer. Return an errno
* error number if the data cannot be read.
*
* @param device The device to read data from.
* @param flags Device specific flags for the driver.
* @param base The base address of the device.
* @param offset The offset in the segment to read.
* @param buffer The buffer to read the data into.
* @param size The amount of data to read.
* @retval 0 No error.
* @retval EIO The read did not complete.
*/
int (*read) (uint32_t device, uint32_t flags, void* base,
uint32_t offset, void* buffer, size_t size);
/**
* Write data from the buffer to the device. Return an errno
* error number if the device cannot be written to.
*
* @param device The device to write data to.
* @param flags Device specific flags for the driver.
* @param base The base address of the device.
* @param offset The offset in the device to write to.
* @param buffer The buffer to write the data from.
* @param size The amount of data to write.
* @retval 0 No error.
* @retval EIO The write did not complete or verify.
*/
int (*write) (uint32_t device, uint32_t flags, void* base,
uint32_t offset, const void* buffer, size_t size);
/**
* Verify data in the buffer to the data in the device. Return an
* errno error number if the device cannot be read or the data verified.
*
* @param device The device to verify the data with.
* @param flags Device specific flags for the driver.
* @param base The base address of the device.
* @param offset The offset in the device to verify.
* @param buffer The buffer to verify the data in the device with.
* @param size The amount of data to verify.
* @retval 0 No error.
* @retval EIO The data did not verify.
*/
int (*verify) (uint32_t device, uint32_t flags, void* base,
uint32_t offset, const void* buffer, size_t size);
} rtems_nvdisk_driver_handlers;
/**
* NV Device Descriptor holds the description of a device that is
* part of the NV disk.
*
* Typically this structure is part of a table of the device which
* is referenced in the nvdisk configuration table.
* The reference is kept in the driver and used all the time to
* manage the nv device, therefore it must always exist.
*/
typedef struct rtems_nvdisk_device_desc
{
uint32_t flags; /**< Private user flags. */
void* base; /**< Base address of the device. */
uint32_t size; /**< Size of the device. */
const rtems_nvdisk_driver_handlers* nv_ops; /**< Device handlers. */
} rtems_nvdisk_device_desc;
/**
* RTEMS Non-Volatile Disk configuration table used to initialise the
* driver.
*/
typedef struct rtems_nvdisk_config
{
uint32_t block_size; /**< The block size. */
uint32_t device_count; /**< The number of devices. */
const rtems_nvdisk_device_desc* devices; /**< The device descriptions. */
uint32_t flags; /**< Set of flags to control
driver. */
uint32_t info_level; /**< Default info level. */
} rtems_nvdisk_config;
/*
* Driver flags.
*/
/**
* Check the pages during initialisation to see which pages are
* valid and which are not. This could slow down initialising the
* disk driver.
*/
#define RTEMS_NVDISK_CHECK_PAGES (1 << 0)
/**
* Non-volatile disk device driver initialization. Place in a table as the
* initialisation entry and remainder of the entries are the RTEMS block
* device generic handlers.
*
* @param major NV disk major device number.
* @param minor Minor device number, not applicable.
* @param arg Initialization argument, not applicable.
* @return The rtems_device_driver is actually just
* rtems_status_code.
*/
rtems_device_driver
rtems_nvdisk_initialize (rtems_device_major_number major,
rtems_device_minor_number minor,
void* arg);
/**
* External reference to the configuration. Please supply.
* Support is present in confdefs.h for providing this variable.
*/
extern const rtems_nvdisk_config rtems_nvdisk_configuration[];
/**
* External reference to the number of configurations. Please supply.
* Support is present in confdefs.h for providing this variable.
*/
extern uint32_t rtems_nvdisk_configuration_size;
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif
