/* Clock_init() * * This routine initializes the Tick Timer 2 on the MVME162 board. * The tick frequency is 1 millisecond. * * Input parameters: NONE * * Output parameters: NONE * * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994. * On-Line Applications Research Corporation (OAR). * All rights assigned to U.S. Government, 1994. * * This material may be reproduced by or for the U.S. Government pursuant * to the copyright license under the clause at DFARS 252.227-7013. This * notice must appear in all copies of this file and its derivatives. * * Modifications of respective RTEMS file: COPYRIGHT (c) 1994. * EISCAT Scientific Association. M.Savitski * * This material is a part of the MVME162 Board Support Package * for the RTEMS executive. Its licensing policies are those of the * RTEMS above. * * $Id$ */ #include #include #include #include #define MS_COUNT 1000 /* T2's countdown constant (1 ms) */ #define CLOCK_INT_LEVEL 6 /* T2's interrupt level */ rtems_unsigned32 Clock_isrs; /* ISRs until next tick */ volatile rtems_unsigned32 Clock_driver_ticks; /* ticks since initialization */ rtems_isr_entry Old_ticker; rtems_device_driver Clock_initialize( rtems_device_major_number major, rtems_device_minor_number minor, void *pargp, rtems_id tid, rtems_unsigned32 *rval ) { Install_clock( Clock_isr ); } void ReInstall_clock(rtems_isr_entry clock_isr) { rtems_unsigned32 isrlevel; rtems_interrupt_disable( isrlevel ); (void) set_vector( clock_isr, VBR0 * 0x10 + 0x9, 1 ); rtems_interrupt_enable( isrlevel ); } void Install_clock(rtems_isr_entry clock_isr ) { Clock_driver_ticks = 0; Clock_isrs = BSP_Configuration.microseconds_per_tick / 1000; if ( BSP_Configuration.ticks_per_timeslice ) { Old_ticker = (rtems_isr_entry) set_vector( clock_isr, VBR0 * 0x10 + 0x9, 1 ); lcsr->vector_base |= MASK_INT; /* unmask VMEchip2 interrupts */ lcsr->to_ctl = 0xE7; /* prescaler to 1 MHz (see Appendix A1) */ lcsr->timer_cmp_2 = MS_COUNT; lcsr->timer_cnt_2 = 0; /* clear counter */ lcsr->board_ctl |= 0x700; /* increment, reset-on-compare, and */ /* clear-overflow-cnt */ lcsr->intr_level[0] |= CLOCK_INT_LEVEL * 0x10; /* set int level */ lcsr->intr_ena |= 0x02000000; /* enable tick timer 2 interrupt */ atexit( Clock_exit ); } } void Clock_exit( void ) { /* Dummy for now. See other m68k BSP's for code examples */ }