/*
* Clock Tick Device Driver
*
* This routine initializes LEON timer 1 which used for the clock tick.
*
* The tick frequency is directly programmed to the configured number of
* microseconds per tick.
*
* COPYRIGHT (c) 1989-1998.
* On-Line Applications Research Corporation (OAR).
*
* Modified for LEON3 BSP.
* COPYRIGHT (c) 2004.
* Gaisler Research.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*
*
* $Id$
*/
#include <stdlib.h>
#include <bsp.h>
#include <rtems/libio.h>
/*
* The Real Time Clock Counter Timer uses this trap type.
*/
#define CLOCK_VECTOR LEON_TRAP_TYPE( LEON_INTERRUPT_TIMER1 )
/*
* Clock ticks since initialization
*/
volatile uint32_t Clock_driver_ticks;
volatile LEON3_Timer_Regs_Map *LEON3_Timer_Regs = 0;
static int clkirq;
/*
* This is the value programmed into the count down timer. It
* is artificially lowered when SIMSPARC_FAST_IDLE is defined to
* cut down how long we spend in the idle task while executing on
* the simulator.
*/
extern uint32_t CPU_SPARC_CLICKS_PER_TICK;
rtems_isr_entry Old_ticker;
void Clock_exit( void );
/*
* These are set by clock driver during its init
*/
rtems_device_major_number rtems_clock_major = ~0;
rtems_device_minor_number rtems_clock_minor;
/*
* Clock_isr
*
* This is the clock tick interrupt handler.
*
* Input parameters:
* vector - vector number
*
* Output parameters: NONE
*
* Return values: NONE
*
*/
rtems_isr Clock_isr(
rtems_vector_number vector
)
{
/*
* If we are in "fast idle" mode, then the value for clicks per tick
* is lowered to decrease the amount of time spent executing the idle
* task while using the SPARC Instruction Simulator.
*/
#if SIMSPARC_FAST_IDLE
LEON_REG.Real_Time_Clock_Counter = CPU_SPARC_CLICKS_PER_TICK;
LEON_REG_Set_Real_Time_Clock_Timer_Control(
LEON_REG_TIMER_COUNTER_ENABLE_COUNTING |
LEON_REG_TIMER_COUNTER_LOAD_COUNTER
);
#endif
/*
* The driver has seen another tick.
*/
Clock_driver_ticks += 1;
/*
* Real Time Clock counter/timer is set to automatically reload.
*/
rtems_clock_tick();
}
/*
* Install_clock
*
* This routine actually performs the hardware initialization for the clock.
*
* Input parameters:
* clock_isr - clock interrupt service routine entry point
*
* Output parameters: NONE
*
* Return values: NONE
*
*/
void Install_clock(
rtems_isr_entry clock_isr
)
{
int i;
unsigned int iobar, conf;
Clock_driver_ticks = 0;
/* Find GP Timer */
i = 0;
while (i < amba_conf.apbslv.devnr)
{
conf = amba_get_confword(amba_conf.apbslv, i, 0);
if ((amba_vendor(conf) == VENDOR_GAISLER) && (amba_device(conf) == GAISLER_GPTIMER))
{
iobar = amba_apb_get_membar(amba_conf.apbslv, i);
LEON3_Timer_Regs = (volatile LEON3_Timer_Regs_Map *) amba_iobar_start(amba_conf.apbmst, iobar);
break;
}
i++;
}
clkirq = (LEON3_Timer_Regs->status & 0xfc) >> 3;
if ( BSP_Configuration.ticks_per_timeslice ) {
Old_ticker = (rtems_isr_entry) set_vector( clock_isr, LEON_TRAP_TYPE(clkirq), 1 );
LEON3_Timer_Regs->reload_t0 = CPU_SPARC_CLICKS_PER_TICK - 1;
LEON3_Timer_Regs->conf_t0 = LEON3_GPTIMER_EN | LEON3_GPTIMER_RL | LEON3_GPTIMER_LD | LEON3_GPTIMER_IRQEN;
atexit( Clock_exit );
}
}
/*
* Clock_exit
*
* This routine allows the clock driver to exit by masking the interrupt and
* disabling the clock's counter.
*
* Input parameters: NONE
*
* Output parameters: NONE
*
* Return values: NONE
*
*/
void Clock_exit( void )
{
if ( BSP_Configuration.ticks_per_timeslice ) {
LEON_Mask_interrupt(LEON_TRAP_TYPE(clkirq));
LEON3_Timer_Regs->conf_t0 = 0;
/* do not restore old vector */
}
}
/*
* Clock_initialize
*
* This routine initializes the clock driver.
*
* Input parameters:
* major - clock device major number
* minor - clock device minor number
* parg - pointer to optional device driver arguments
*
* Output parameters: NONE
*
* Return values:
* rtems_device_driver status code
*/
rtems_device_driver Clock_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
Install_clock( Clock_isr );
/*
* make major/minor avail to others such as shared memory driver
*/
rtems_clock_major = major;
rtems_clock_minor = minor;
return RTEMS_SUCCESSFUL;
}
/*
* Clock_control
*
* This routine is the clock device driver control entry point.
*
* Input parameters:
* major - clock device major number
* minor - clock device minor number
* parg - pointer to optional device driver arguments
*
* Output parameters: NONE
*
* Return values:
* rtems_device_driver status code
*/
rtems_device_driver Clock_control(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
uint32_t isrlevel;
rtems_libio_ioctl_args_t *args = pargp;
if (args == 0)
goto done;
/*
* This is hokey, but until we get a defined interface
* to do this, it will just be this simple...
*/
if (args->command == rtems_build_name('I', 'S', 'R', ' '))
{
Clock_isr(LEON_TRAP_TYPE(clkirq));
}
else if (args->command == rtems_build_name('N', 'E', 'W', ' '))
{
rtems_interrupt_disable( isrlevel );
(void) set_vector( args->buffer, LEON_TRAP_TYPE(clkirq), 1 );
rtems_interrupt_enable( isrlevel );
}
done:
return RTEMS_SUCCESSFUL;
}