diff options
Diffstat (limited to 'c/src/lib/libbsp/c4x/c4xsim/clock/clock.c')
| -rw-r--r-- | c/src/lib/libbsp/c4x/c4xsim/clock/clock.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/c4x/c4xsim/clock/clock.c b/c/src/lib/libbsp/c4x/c4xsim/clock/clock.c new file mode 100644 index 0000000000..7b36ebb359 --- /dev/null +++ b/c/src/lib/libbsp/c4x/c4xsim/clock/clock.c @@ -0,0 +1,225 @@ +/* ckinit.c + * + * This file provides a template for the clock device driver initialization. + * + * COPYRIGHT (c) 1989-1999. + * On-Line Applications Research Corporation (OAR). + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.OARcorp.com/rtems/license.html. + * + * $Id$ + */ + +#include <stdlib.h> + +#include <rtems.h> +#include <rtems/libio.h> +#include <bsp.h> +#include <c4xio.h> + +void Clock_exit( void ); +rtems_isr Clock_isr( rtems_vector_number vector ); + +rtems_unsigned32 Clock_counter_register_value; + +/* + * The interrupt vector number associated with the clock tick device + * driver. + */ + +#define CLOCK_VECTOR 9 + +/* + * Clock_driver_ticks is a monotonically increasing counter of the + * number of clock ticks since the driver was initialized. + */ + +volatile rtems_unsigned32 Clock_driver_ticks; + +/* + * These are set by clock driver during its init + */ + +rtems_device_major_number rtems_clock_major = ~0; +rtems_device_minor_number rtems_clock_minor; + +/* + * The previous ISR on this clock tick interrupt vector. + */ + +rtems_isr_entry Old_ticker; + +void Clock_exit( void ); + + +/* + * Isr Handler + */ + +#define FAST_IDLE 1 +#if FAST_IDLE +int Clock_in_fast_idle_mode = 0; +#endif + +rtems_isr Clock_isr( + rtems_vector_number vector +) +{ + /* + * The counter register gets reset automatically as well as the + * interrupt occurred flag so we should not have to do anything + * with the hardware. + */ + + /* + * Bump the number of clock driver ticks since initialization + */ + + Clock_driver_ticks += 1; + + rtems_clock_tick(); + +#if FAST_IDLE + if ( Clock_in_fast_idle_mode ) { + if ( _Thread_Executing == _Thread_Idle && _Thread_Heir != _Thread_Idle ) { + c4x_timer_stop( C4X_TIMER_0 ); + c4x_timer_set_counter( C4X_TIMER_0, 0 ); + c4x_timer_set_period( C4X_TIMER_0, Clock_counter_register_value ); + c4x_timer_start( C4X_TIMER_0 ); + Clock_in_fast_idle_mode = 0; + } + } else { + if ( _Thread_Executing == _Thread_Idle && _Thread_Heir == _Thread_Idle ) { + c4x_timer_stop( C4X_TIMER_0 ); + c4x_timer_set_counter( C4X_TIMER_0, 0 ); + c4x_timer_set_period( C4X_TIMER_0, Clock_counter_register_value >> 5 ); + c4x_timer_start( C4X_TIMER_0 ); + } + } +#endif +} + +/* + * Install_clock + * + * Install a clock tick handler and reprograms the chip. This + * is used to initially establish the clock tick. + */ + +void Install_clock( + rtems_isr_entry clock_isr +) +{ + extern int _ClockFrequency; + float tmp; + int tmpi; + /* + * Initialize the clock tick device driver variables + */ + + Clock_driver_ticks = 0; + + tmpi = ((int) &_ClockFrequency) * 1000000; /* ClockFrequency is in Mhz */ + tmp = (float) tmpi / 2.0; + tmp = ((float) BSP_Configuration.microseconds_per_tick / 1000000.0) * (tmp); + + Clock_counter_register_value = (unsigned int) tmp; +#if 0 + Clock_counter_register_value = + (unsigned32) ((float) BSP_Configuration.microseconds_per_tick / + ((float)_ClockFrequency / 2.0))); +#endif + c4x_timer_stop( C4X_TIMER_0 ); + c4x_timer_set_counter( C4X_TIMER_0, 0 ); + c4x_timer_set_period( C4X_TIMER_0, Clock_counter_register_value ); + c4x_timer_start( C4X_TIMER_0 ); + + c3x_set_ie( c3x_get_ie() | 0x100 ); + + /* + * If ticks_per_timeslice is configured as non-zero, then the user + * wants a clock tick. + */ + + Old_ticker = (rtems_isr_entry) set_vector( clock_isr, CLOCK_VECTOR, 1 ); + /* + * Hardware specific initialize goes here + */ + + /* XXX */ + + /* + * Schedule the clock cleanup routine to execute if the application exits. + */ + + atexit( Clock_exit ); +} + +/* + * Clean up before the application exits + */ + +void Clock_exit( void ) +{ + /* XXX: turn off the timer interrupts */ + + /* XXX: If necessary, restore the old vector */ +} + +/* + * Clock_initialize + * + * Device driver entry point for clock tick driver initialization. + */ + +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; +} + +rtems_device_driver Clock_control( + rtems_device_major_number major, + rtems_device_minor_number minor, + void *pargp +) +{ + rtems_unsigned32 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(CLOCK_VECTOR); + } + else if (args->command == rtems_build_name('N', 'E', 'W', ' ')) + { + rtems_interrupt_disable( isrlevel ); + (void) set_vector( args->buffer, CLOCK_VECTOR, 1 ); + rtems_interrupt_enable( isrlevel ); + } + +done: + return RTEMS_SUCCESSFUL; +} |