diff options
Diffstat (limited to 'c/src/lib/libbsp/m68k/idp/timer/timer.c')
-rw-r--r-- | c/src/lib/libbsp/m68k/idp/timer/timer.c | 121 |
1 files changed, 0 insertions, 121 deletions
diff --git a/c/src/lib/libbsp/m68k/idp/timer/timer.c b/c/src/lib/libbsp/m68k/idp/timer/timer.c deleted file mode 100644 index 176f393e45..0000000000 --- a/c/src/lib/libbsp/m68k/idp/timer/timer.c +++ /dev/null @@ -1,121 +0,0 @@ -/* Timer_init() - * - * This routine initializes the MC68230 timer on the Motorola IDP board. - * - * Input parameters: NONE - * - * Output parameters: NONE - * - * NOTE: This routine will not work if the optimizer is enabled - * for some compilers. The multiple writes to the MC68230 - * may be optimized away. - * - * It is important that the timer start/stop overhead be - * determined when porting or modifying this code. - * - * Code Modified for the MC68230 by Doug McBride, Colorado Space Grant College - * - * 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. - * - * $Id$ - */ - - -#include "rtems.h" -#include "cpu.h" -#include "bsp.h" -#include "mc68230.h" - -#define TIMER_VECTOR 0x4D - -int Ttimer_val; -rtems_boolean Timer_driver_Find_average_overhead; - -rtems_isr timerisr(); - -void Timer_initialize() -{ - (void) set_vector( timerisr, TIMER_VECTOR, 0 ); /* install ISR */ - - Ttimer_val = 0; /* clear timer ISR count */ - - /* some PI/T initialization stuff here */ - /* Set up the interrupt vector on the MC68230 chip: - TIVR = TIMER_VECTOR; */ - MC68230_WRITE (TIVR, TIMER_VECTOR); - - /* Set CPRH through CPRL to maximum count to reduce interrupt overhead - CPRH = 0xFF; - CPRM = 0xFF; - CPRL = 0xFF; */ - MC68230_WRITE (CPRH, 0xFF); - MC68230_WRITE (CPRM, 0xFF); - MC68230_WRITE (CPRL, 0xFF); - - /* Enable timer and use it as an external periodic interrupt generator - TCR = 0xA1; */ - MC68230_WRITE (TCR, 0xA1); - -} - -#define AVG_OVERHEAD 9 /* may not be right -- do this later */ -#define LEAST_VALID 10 /* Don't trust a value lower than this */ - -int Read_timer() -{ - rtems_unsigned8 data; - rtems_unsigned8 msb, osb, lsb; - rtems_unsigned32 remaining, total; - - /* Disable timer so that timer can be read - data = TCR; - TCR = (data & 0xFE); */ - MC68230_READ (TCR, data); - MC68230_WRITE (TCR, (data & 0xFE)); - - /* Read the counter value - msb = CNTRH; - osb = CNTRM; - lsb = CNTRL; */ - MC68230_READ (CNTRH, msb); - MC68230_READ (CNTRM, osb); - MC68230_READ (CNTRL, lsb); - - /* Calculate the time so far */ - remaining = 0x1000000 - ((msb << 16) + (osb << 8) + lsb); - total = (Ttimer_val * 0x1000000) + remaining; - - /* Enable timer so that timer can continue - TCR = 0xA1; */ - MC68230_WRITE (TCR, 0xA1); - - /* do not restore old vector */ - if ( Timer_driver_Find_average_overhead == 1 ) - return total; /* in countdown units */ - - if ( total < LEAST_VALID ) - return 0; /* below timer resolution */ - - /* Clocked at 6.5 Mhz */ - /* Avoid floating point problems, be lazy, and return the total minus - the average overhead */ - return (total - AVG_OVERHEAD); -} - -rtems_status_code Empty_function( void ) -{ - return RTEMS_SUCCESSFUL; -} - -void Set_find_average_overhead( - rtems_boolean find_flag -) -{ - Timer_driver_Find_average_overhead = find_flag; -} |