diff options
| -rw-r--r-- | sys/amd64/conf/NOTES | 13 | ||||
| -rw-r--r-- | sys/amd64/isa/clock.c | 112 | ||||
| -rw-r--r-- | sys/conf/options.amd64 | 2 | ||||
| -rw-r--r-- | sys/conf/options.i386 | 2 | ||||
| -rw-r--r-- | sys/conf/options.pc98 | 2 | ||||
| -rw-r--r-- | sys/i386/conf/NOTES | 13 | ||||
| -rw-r--r-- | sys/i386/isa/clock.c | 122 | ||||
| -rw-r--r-- | sys/isa/atrtc.c | 122 | ||||
| -rw-r--r-- | sys/pc98/cbus/clock.c | 98 | ||||
| -rw-r--r-- | sys/pc98/cbus/pcrtc.c | 98 | ||||
| -rw-r--r-- | sys/pc98/conf/NOTES | 17 |
11 files changed, 0 insertions, 601 deletions
diff --git a/sys/amd64/conf/NOTES b/sys/amd64/conf/NOTES index bfa1c9b..9be763e 100644 --- a/sys/amd64/conf/NOTES +++ b/sys/amd64/conf/NOTES @@ -88,19 +88,6 @@ options BPF_JITTER ##################################################################### # CLOCK OPTIONS -# The following options are used for debugging clock behavior only, and -# should not be used for production systems. - -# CLK_CALIBRATION_LOOP causes clock calibration to be run in a loop at -# startup until the user presses a key. (The i8254 clock is always -# calibrated relative to the RTC (mc146818a) and this option causes the -# calibration to be repeated.) -options CLK_CALIBRATION_LOOP - -# CLK_USE_I8254_CALIBRATION causes the calibrated frequency of the i8254 -# clock to actually be used. -options CLK_USE_I8254_CALIBRATION - # Provide read/write access to the memory in the clock chip. device nvram # Access to rtc cmos via /dev/nvram diff --git a/sys/amd64/isa/clock.c b/sys/amd64/isa/clock.c index 342fe18..5cc076e 100644 --- a/sys/amd64/isa/clock.c +++ b/sys/amd64/isa/clock.c @@ -430,86 +430,6 @@ 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) { @@ -547,42 +467,10 @@ 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); diff --git a/sys/conf/options.amd64 b/sys/conf/options.amd64 index 258b0b7..b05b770 100644 --- a/sys/conf/options.amd64 +++ b/sys/conf/options.amd64 @@ -21,8 +21,6 @@ LINPROCFS opt_dontuse.h LINSYSFS opt_dontuse.h NDISAPI opt_dontuse.h -CLK_CALIBRATION_LOOP opt_clock.h -CLK_USE_I8254_CALIBRATION opt_clock.h TIMER_FREQ opt_clock.h # options for serial support diff --git a/sys/conf/options.i386 b/sys/conf/options.i386 index 3fc3fb1..8cdaa5e 100644 --- a/sys/conf/options.i386 +++ b/sys/conf/options.i386 @@ -36,8 +36,6 @@ KVA_PAGES opt_global.h # Physical address extensions and support for >4G ram. As above. PAE opt_global.h -CLK_CALIBRATION_LOOP opt_clock.h -CLK_USE_I8254_CALIBRATION opt_clock.h TIMER_FREQ opt_clock.h CPU_ATHLON_SSE_HACK opt_cpu.h diff --git a/sys/conf/options.pc98 b/sys/conf/options.pc98 index 605870a..d910ff2 100644 --- a/sys/conf/options.pc98 +++ b/sys/conf/options.pc98 @@ -31,8 +31,6 @@ PECOFF_SUPPORT opt_dontuse.h # Change KVM size. Changes things all over the kernel. KVA_PAGES opt_global.h -CLK_CALIBRATION_LOOP opt_clock.h -CLK_USE_I8254_CALIBRATION opt_clock.h TIMER_FREQ opt_clock.h # options for serial support diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES index 7fac7b8..c8401d0 100644 --- a/sys/i386/conf/NOTES +++ b/sys/i386/conf/NOTES @@ -259,19 +259,6 @@ options BPF_JITTER ##################################################################### # CLOCK OPTIONS -# The following options are used for debugging clock behavior only, and -# should not be used for production systems. - -# CLK_CALIBRATION_LOOP causes clock calibration to be run in a loop at -# startup until the user presses a key. (The i8254 clock is always -# calibrated relative to the RTC (mc146818a) and this option causes the -# calibration to be repeated.) -options CLK_CALIBRATION_LOOP - -# CLK_USE_I8254_CALIBRATION causes the calibrated frequency of the i8254 -# clock to actually be used. -options CLK_USE_I8254_CALIBRATION - # Provide read/write access to the memory in the clock chip. device nvram # Access to rtc cmos via /dev/nvram diff --git a/sys/i386/isa/clock.c b/sys/i386/isa/clock.c index d5aa118..09a9dc4 100644 --- a/sys/i386/isa/clock.c +++ b/sys/i386/isa/clock.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); 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); diff --git a/sys/pc98/cbus/clock.c b/sys/pc98/cbus/clock.c index 38f9854..05d34c5 100644 --- a/sys/pc98/cbus/clock.c +++ b/sys/pc98/cbus/clock.c @@ -69,7 +69,6 @@ __FBSDID("$FreeBSD$"); #include <sys/limits.h> #include <sys/module.h> #include <sys/sysctl.h> -#include <sys/cons.h> #include <sys/power.h> #include <machine/clock.h> @@ -325,71 +324,6 @@ DELAY(int n) #endif } -static u_int -calibrate_clocks(void) -{ - int timeout; - u_int count, prev_count, tot_count; - u_short sec, start_sec; - - if (bootverbose) - printf("Calibrating clock(s) ... "); - /* Check ARTIC. */ - if (!(PC98_SYSTEM_PARAMETER(0x458) & 0x80) && - !(PC98_SYSTEM_PARAMETER(0x45b) & 0x04)) - goto fail; - timeout = 100000000; - - /* Read the ARTIC. */ - sec = inw(0x5e); - - /* Wait for the ARTIC to changes. */ - start_sec = sec; - for (;;) { - sec = inw(0x5e); - 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; - - start_sec = sec; - for (;;) { - sec = inw(0x5e); - 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 + 1200) || /* 1200 = 307.2KHz >> 8 */ - (sec < start_sec && - (u_int)sec + 0x10000 == (u_int)start_sec + 1200)) - 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) { @@ -459,38 +393,6 @@ i8254_init(void) void startrtclock() { - u_int delta, freq; - - 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); diff --git a/sys/pc98/cbus/pcrtc.c b/sys/pc98/cbus/pcrtc.c index 38f9854..05d34c5 100644 --- a/sys/pc98/cbus/pcrtc.c +++ b/sys/pc98/cbus/pcrtc.c @@ -69,7 +69,6 @@ __FBSDID("$FreeBSD$"); #include <sys/limits.h> #include <sys/module.h> #include <sys/sysctl.h> -#include <sys/cons.h> #include <sys/power.h> #include <machine/clock.h> @@ -325,71 +324,6 @@ DELAY(int n) #endif } -static u_int -calibrate_clocks(void) -{ - int timeout; - u_int count, prev_count, tot_count; - u_short sec, start_sec; - - if (bootverbose) - printf("Calibrating clock(s) ... "); - /* Check ARTIC. */ - if (!(PC98_SYSTEM_PARAMETER(0x458) & 0x80) && - !(PC98_SYSTEM_PARAMETER(0x45b) & 0x04)) - goto fail; - timeout = 100000000; - - /* Read the ARTIC. */ - sec = inw(0x5e); - - /* Wait for the ARTIC to changes. */ - start_sec = sec; - for (;;) { - sec = inw(0x5e); - 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; - - start_sec = sec; - for (;;) { - sec = inw(0x5e); - 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 + 1200) || /* 1200 = 307.2KHz >> 8 */ - (sec < start_sec && - (u_int)sec + 0x10000 == (u_int)start_sec + 1200)) - 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) { @@ -459,38 +393,6 @@ i8254_init(void) void startrtclock() { - u_int delta, freq; - - 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); diff --git a/sys/pc98/conf/NOTES b/sys/pc98/conf/NOTES index b5c3b00..6f50f50 100644 --- a/sys/pc98/conf/NOTES +++ b/sys/pc98/conf/NOTES @@ -197,23 +197,6 @@ options BPF_JITTER ##################################################################### -# CLOCK OPTIONS - -# The following options are used for debugging clock behavior only, and -# should not be used for production systems. - -# CLK_CALIBRATION_LOOP causes clock calibration to be run in a loop at -# startup until the user presses a key. (The i8254 clock is always -# calibrated relative to the RTC (mc146818a) and this option causes the -# calibration to be repeated.) -options CLK_CALIBRATION_LOOP - -# CLK_USE_I8254_CALIBRATION causes the calibrated frequency of the i8254 -# clock to actually be used. -options CLK_USE_I8254_CALIBRATION - - -##################################################################### # MISCELLANEOUS DEVICES AND OPTIONS # |
