13. IDE Controller Driver¶
13.1. Introduction¶
The IDE Controller driver is responsible for providing an interface to an IDE Controller. The capabilities provided by this driver are:
- Read IDE Controller register
- Write IDE Controller register
- Read data block through IDE Controller Data Register
- Write data block through IDE Controller Data Register
The reference implementation for an IDE Controller driver can be found in
$RTEMS_SRC_ROOT/c/src/libchip/ide
. This driver is based on the libchip
concept and allows to work with any of the IDE Controller chips simply by
appropriate configuration of BSP. Drivers for a particular IDE Controller chips
locate in the following directories: drivers for well-known IDE Controller
chips locate into $RTEMS_SRC_ROOT/c/src/libchip/ide
, drivers for IDE
Controller chips integrated with CPU locate into
$RTEMS_SRC_ROOT/c/src/lib/libcpu/myCPU
and drivers for custom IDE
Controller chips (for example, implemented on FPGA) locate into
$RTEMS_SRC_ROOT/c/src/lib/libbsp/myBSP
. There is a README file in these
directories for each supported IDE Controller chip. Each of these README
explains how to configure a BSP for that particular IDE Controller chip.
13.2. Initialization¶
IDE Controller chips used by a BSP are statically configured into
IDE_Controller_Table
. The ide_controller_initialize
routine is
responsible for initialization of all configured IDE controller chips.
Initialization order of the chips based on the order the chips are defined in
the IDE_Controller_Table
.
The following actions are performed by the IDE Controller driver initialization routine:
rtems_device_driver ide_controller_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor_arg,
void *arg
)
{
for each IDE Controller chip configured in IDE_Controller_Table
if (BSP dependent probe(if exists) AND device probe for this IDE chip
indicates it is present)
perform initialization of the particular chip
register device with configured name for this chip
}
13.3. Read IDE Controller Register¶
The ide_controller_read_register
routine reads the content of the IDE
Controller chip register. IDE Controller chip is selected via the minor
number. This routine is not allowed to be called from an application.
void ide_controller_read_register(
rtems_device_minor_number minor,
unsigned32 reg,
unsigned32 *value
)
{
get IDE Controller chip configuration information from
IDE_Controller_Table by minor number
invoke read register routine for the chip
}
13.4. Write IDE Controller Register¶
The ide_controller_write_register
routine writes IDE Controller chip
register with specified value. IDE Controller chip is selected via the minor
number. This routine is not allowed to be called from an application.
void ide_controller_write_register(
rtems_device_minor_number minor,
unsigned32 reg,
unsigned32 value
)
{
get IDE Controller chip configuration information from
IDE_Controller_Table by minor number
invoke write register routine for the chip
}
13.5. Read Data Block Through IDE Controller Data Register¶
The ide_controller_read_data_block
provides multiple consequent read of the
IDE Controller Data Register. IDE Controller chip is selected via the minor
number. The same functionality may be achieved via separate multiple calls of
ide_controller_read_register
routine but ide_controller_read_data_block
allows to escape functions call overhead. This routine is not allowed to be
called from an application.
void ide_controller_read_data_block(
rtems_device_minor_number minor,
unsigned16 block_size,
blkdev_sg_buffer *bufs,
uint32_t *cbuf,
uint32_t *pos
)
{
get IDE Controller chip configuration information from
IDE_Controller_Table by minor number
invoke read data block routine for the chip
}
13.6. Write Data Block Through IDE Controller Data Register¶
The ide_controller_write_data_block
provides multiple consequent write into
the IDE Controller Data Register. IDE Controller chip is selected via the minor
number. The same functionality may be achieved via separate multiple calls of
ide_controller_write_register
routine but
ide_controller_write_data_block
allows to escape functions call
overhead. This routine is not allowed to be called from an application.
void ide_controller_write_data_block(
rtems_device_minor_number minor,
unsigned16 block_size,
blkdev_sg_buffer *bufs,
uint32_t *cbuf,
uint32_t *pos
)
{
get IDE Controller chip configuration information from
IDE_Controller_Table by minor number
invoke write data block routine for the chip
}