diff options
Diffstat (limited to 'c/src/lib/libbsp/m68k/gen68360/clock/clock.c')
| -rw-r--r-- | c/src/lib/libbsp/m68k/gen68360/clock/clock.c | 101 |
1 files changed, 0 insertions, 101 deletions
diff --git a/c/src/lib/libbsp/m68k/gen68360/clock/clock.c b/c/src/lib/libbsp/m68k/gen68360/clock/clock.c deleted file mode 100644 index 56fd0e19fa..0000000000 --- a/c/src/lib/libbsp/m68k/gen68360/clock/clock.c +++ /dev/null @@ -1,101 +0,0 @@ -/* - * This routine initializes the MC68360 Periodic Interval Timer - * - * The PIT has rather poor resolution, but it is easy to set up - * and requires no housekeeping once it is going. - * - * W. Eric Norum - * Saskatchewan Accelerator Laboratory - * University of Saskatchewan - * Saskatoon, Saskatchewan, CANADA - * eric@skatter.usask.ca - */ - -#include <rtems.h> -#include <bsp.h> -#include <rtems/m68k/m68360.h> - -#define CLOCK_VECTOR 120 -#define CLOCK_IRQ_LEVEL 4 - -char M360DefaultWatchdogFeeder = 1; - -/* - * RTEMS and hardware have different notions of clock rate. - */ -static unsigned long rtems_nsec_per_tick; -static unsigned long pit_nsec_per_tick; -static unsigned long nsec; - -/* - * Periodic interval timer interrupt handler - * See if it's really time for a `tick' - * Perform a dummy read of DPRAM (work around bug in Rev. B of the 68360). - * Feed the watchdog - * Application code can override this by - * setting M360DefaultWatchdogFeeder to zero. - */ -#define Clock_driver_support_at_tick() \ - do { \ - nsec += pit_nsec_per_tick; \ - if (nsec >= rtems_nsec_per_tick) \ - return; \ - nsec -= rtems_nsec_per_tick; \ - m360.dpram0[0]; \ - if (M360DefaultWatchdogFeeder) { \ - m360.swsr = 0x55; \ - m360.swsr = 0xAA; \ - } \ - } while (0) \ - -/* - * Attach clock interrupt handler - */ -#define Clock_driver_support_install_isr( _new ) \ - set_vector(_new, CLOCK_VECTOR, 1) - -/* - * Turn off the clock - */ -#define Clock_driver_support_shutdown_hardware() \ - do { \ - m360.pitr &= ~0xFF; \ - } while(0) - -/* - * Set up the clock hardware - * The rate at which the periodic interval timer - * can generate interrupts is almost certainly not - * the same as desired by the BSP configuration. - * Handle the difference by choosing the largest PIT - * interval which is less than or equal to the RTEMS - * interval and skipping some hardware interrupts. - * To reduce the jitter in the calls to RTEMS the - * hardware interrupt interval is never greater than - * the maximum non-prescaled value from the PIT. - * - * For a 25 MHz external clock the basic clock rate is - * 40 nsec * 128 * 4 = 20.48 usec/tick - */ -extern int m360_clock_rate; - -#define Clock_driver_support_initialize_hardware() \ - do { \ - unsigned int divisor; \ - unsigned long nsec_per_chip_tick = 1000000000 / m360_clock_rate; \ - unsigned long nsec_per_pit_tick = 512 * nsec_per_chip_tick; \ - rtems_nsec_per_tick = rtems_configuration_get_microseconds_per_tick() * 1000; \ - divisor = rtems_nsec_per_tick / nsec_per_pit_tick; \ - if (divisor > 255) \ - divisor = 255; \ - else if (divisor == 0) \ - divisor = 1; \ - pit_nsec_per_tick = nsec_per_pit_tick * divisor; \ - m360.pitr &= ~0x1FF; \ - m360.picr = (CLOCK_IRQ_LEVEL << 8) | CLOCK_VECTOR; \ - m360.pitr |= divisor; \ - } while (0) - -#define CLOCK_DRIVER_USE_DUMMY_TIMECOUNTER - -#include "../../../shared/clockdrv_shell.h" |