diff options
Diffstat (limited to 'sys/amd64/isa/clock.c')
| -rw-r--r-- | sys/amd64/isa/clock.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/sys/amd64/isa/clock.c b/sys/amd64/isa/clock.c index 188e25b..310972f 100644 --- a/sys/amd64/isa/clock.c +++ b/sys/amd64/isa/clock.c @@ -34,7 +34,7 @@ * SUCH DAMAGE. * * from: @(#)clock.c 7.2 (Berkeley) 5/12/91 - * $Id: clock.c,v 1.35 1995/06/11 19:31:18 rgrimes Exp $ + * $Id: clock.c,v 1.36 1995/08/25 19:24:56 bde Exp $ */ /* @@ -95,6 +95,8 @@ int disable_rtc_set = 0; /* disable resettodr() if != 0 */ u_int idelayed; #ifdef I586_CPU int pentium_mhz; +long long i586_ctr_bias; +long long i586_last_tick; #endif u_int stat_imask = SWI_CLOCK_MASK; int timer0_max_count; @@ -279,8 +281,6 @@ getit(void) } #ifdef I586_CPU -static long long cycles_per_sec = 0; - /* * Figure out how fast the cyclecounter runs. This must be run with * clock interrupts disabled, but with the timer/counter programmed @@ -293,15 +293,15 @@ calibrate_cyclecounter(void) * Don't need volatile; should always use unsigned if 2's * complement arithmetic is desired. */ - unsigned long long count, last_count; + unsigned long long count; - __asm __volatile(".byte 0xf,0x31" : "=A" (last_count)); + __asm __volatile(".byte 0x0f, 0x30" : : "A"(0LL), "c" (0x10)); DELAY(1000000); __asm __volatile(".byte 0xf,0x31" : "=A" (count)); /* * XX lose if the clock rate is not nearly a multiple of 1000000. */ - pentium_mhz = ((count - last_count) + 500000) / 1000000; + pentium_mhz = (count + 500000) / 1000000; } #endif @@ -569,6 +569,15 @@ cpu_initclocks() /* XXX */ (inthand2_t *)clkintr, &clk_imask, /* unit */ 0); INTREN(IRQ0); +#ifdef I586_CPU + /* + * Finish setting up anti-jitter measures. + */ + if (pentium_mhz) { + I586_CYCLECTR(i586_last_tick); + i586_ctr_bias = i586_last_tick; + } +#endif /* Initialize RTC. */ writertc(RTC_STATUSA, rtc_statusa); |
