diff options
Diffstat (limited to 'sys/isa')
| -rw-r--r-- | sys/isa/atrtc.c | 122 |
1 files changed, 0 insertions, 122 deletions
diff --git a/sys/isa/atrtc.c b/sys/isa/atrtc.c index d5aa118..09a9dc4 100644 --- a/sys/isa/atrtc.c +++ b/sys/isa/atrtc.c @@ -56,34 +56,24 @@ __FBSDID("$FreeBSD$"); #include <sys/systm.h> #include <sys/bus.h> #include <sys/clock.h> -#include <sys/conf.h> -#include <sys/fcntl.h> #include <sys/lock.h> #include <sys/kdb.h> #include <sys/mutex.h> #include <sys/proc.h> -#include <sys/time.h> #include <sys/timetc.h> -#include <sys/uio.h> #include <sys/kernel.h> -#include <sys/limits.h> #include <sys/module.h> #include <sys/sched.h> #include <sys/sysctl.h> -#include <sys/cons.h> -#include <sys/power.h> #include <machine/clock.h> #include <machine/cpu.h> -#include <machine/cputypes.h> #include <machine/frame.h> #include <machine/intr_machdep.h> #include <machine/md_var.h> -#include <machine/psl.h> #ifdef DEV_APIC #include <machine/apicvar.h> #endif -#include <machine/specialreg.h> #include <machine/ppireg.h> #include <machine/timerreg.h> @@ -445,86 +435,6 @@ readrtc(int port) return(bcd2bin(rtcin(port))); } -static u_int -calibrate_clocks(void) -{ - u_int count, prev_count, tot_count; - int sec, start_sec, timeout; - - if (bootverbose) - printf("Calibrating clock(s) ... "); - if (!(rtcin(RTC_STATUSD) & RTCSD_PWR)) - goto fail; - timeout = 100000000; - - /* Read the mc146818A seconds counter. */ - for (;;) { - if (!(rtcin(RTC_STATUSA) & RTCSA_TUP)) { - sec = rtcin(RTC_SEC); - break; - } - if (--timeout == 0) - goto fail; - } - - /* Wait for the mC146818A seconds counter to change. */ - start_sec = sec; - for (;;) { - if (!(rtcin(RTC_STATUSA) & RTCSA_TUP)) { - sec = rtcin(RTC_SEC); - if (sec != start_sec) - break; - } - if (--timeout == 0) - goto fail; - } - - /* Start keeping track of the i8254 counter. */ - prev_count = getit(); - if (prev_count == 0 || prev_count > i8254_max_count) - goto fail; - tot_count = 0; - - /* - * Wait for the mc146818A seconds counter to change. Read the i8254 - * counter for each iteration since this is convenient and only - * costs a few usec of inaccuracy. The timing of the final reads - * of the counters almost matches the timing of the initial reads, - * so the main cause of inaccuracy is the varying latency from - * inside getit() or rtcin(RTC_STATUSA) to the beginning of the - * rtcin(RTC_SEC) that returns a changed seconds count. The - * maximum inaccuracy from this cause is < 10 usec on 486's. - */ - start_sec = sec; - for (;;) { - if (!(rtcin(RTC_STATUSA) & RTCSA_TUP)) - sec = rtcin(RTC_SEC); - count = getit(); - if (count == 0 || count > i8254_max_count) - goto fail; - if (count > prev_count) - tot_count += prev_count - (count - i8254_max_count); - else - tot_count += prev_count - count; - prev_count = count; - if (sec != start_sec) - break; - if (--timeout == 0) - goto fail; - } - - if (bootverbose) { - printf("i8254 clock: %u Hz\n", tot_count); - } - return (tot_count); - -fail: - if (bootverbose) - printf("failed, using default i8254 clock of %u Hz\n", - i8254_freq); - return (i8254_freq); -} - static void set_i8254_freq(u_int freq, int intr_freq) { @@ -601,42 +511,10 @@ i8254_init(void) void startrtclock() { - u_int delta, freq; writertc(RTC_STATUSA, rtc_statusa); writertc(RTC_STATUSB, RTCSB_24HR); - freq = calibrate_clocks(); -#ifdef CLK_CALIBRATION_LOOP - if (bootverbose) { - printf( - "Press a key on the console to abort clock calibration\n"); - while (cncheckc() == -1) - calibrate_clocks(); - } -#endif - - /* - * Use the calibrated i8254 frequency if it seems reasonable. - * Otherwise use the default, and don't use the calibrated i586 - * frequency. - */ - delta = freq > i8254_freq ? freq - i8254_freq : i8254_freq - freq; - if (delta < i8254_freq / 100) { -#ifndef CLK_USE_I8254_CALIBRATION - if (bootverbose) - printf( -"CLK_USE_I8254_CALIBRATION not specified - using default frequency\n"); - freq = i8254_freq; -#endif - i8254_freq = freq; - } else { - if (bootverbose) - printf( - "%d Hz differs from default of %d Hz by more than 1%%\n", - freq, i8254_freq); - } - set_i8254_freq(i8254_freq, hz); tc_init(&i8254_timecounter); |
