diff options
Diffstat (limited to 'include/linux/timex.h')
| -rw-r--r-- | include/linux/timex.h | 73 |
1 files changed, 37 insertions, 36 deletions
diff --git a/include/linux/timex.h b/include/linux/timex.h index 9007313b5b71..998a55d80acf 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -53,47 +53,11 @@ #ifndef _LINUX_TIMEX_H #define _LINUX_TIMEX_H -#include <linux/compiler.h> #include <linux/time.h> -#include <asm/param.h> - #define NTP_API 4 /* NTP API version */ /* - * SHIFT_KG and SHIFT_KF establish the damping of the PLL and are chosen - * for a slightly underdamped convergence characteristic. SHIFT_KH - * establishes the damping of the FLL and is chosen by wisdom and black - * art. - * - * MAXTC establishes the maximum time constant of the PLL. With the - * SHIFT_KG and SHIFT_KF values given and a time constant range from - * zero to MAXTC, the PLL will converge in 15 minutes to 16 hours, - * respectively. - */ -#define SHIFT_PLL 4 /* PLL frequency factor (shift) */ -#define SHIFT_FLL 2 /* FLL frequency factor (shift) */ -#define MAXTC 10 /* maximum time constant (shift) */ - -/* - * SHIFT_USEC defines the scaling (shift) of the time_freq and - * time_tolerance variables, which represent the current frequency - * offset and maximum frequency tolerance. - */ -#define SHIFT_USEC 16 /* frequency offset scale (shift) */ -#define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC)) -#define PPM_SCALE_INV_SHIFT 19 -#define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \ - PPM_SCALE + 1) - -#define MAXPHASE 500000000l /* max phase error (ns) */ -#define MAXFREQ 500000 /* max frequency error (ns/s) */ -#define MAXFREQ_SCALED ((s64)MAXFREQ << NTP_SCALE_SHIFT) -#define MINSEC 256 /* min interval between updates (s) */ -#define MAXSEC 2048 /* max interval between updates (s) */ -#define NTP_PHASE_LIMIT ((MAXPHASE / NSEC_PER_USEC) << 5) /* beyond max. dispersion */ - -/* * syscall interface - used (mainly by NTP daemon) * to discipline kernel clock oscillator */ @@ -199,9 +163,46 @@ struct timex { #define TIME_BAD TIME_ERROR /* bw compat */ #ifdef __KERNEL__ +#include <linux/compiler.h> +#include <linux/types.h> +#include <linux/param.h> + #include <asm/timex.h> /* + * SHIFT_KG and SHIFT_KF establish the damping of the PLL and are chosen + * for a slightly underdamped convergence characteristic. SHIFT_KH + * establishes the damping of the FLL and is chosen by wisdom and black + * art. + * + * MAXTC establishes the maximum time constant of the PLL. With the + * SHIFT_KG and SHIFT_KF values given and a time constant range from + * zero to MAXTC, the PLL will converge in 15 minutes to 16 hours, + * respectively. + */ +#define SHIFT_PLL 4 /* PLL frequency factor (shift) */ +#define SHIFT_FLL 2 /* FLL frequency factor (shift) */ +#define MAXTC 10 /* maximum time constant (shift) */ + +/* + * SHIFT_USEC defines the scaling (shift) of the time_freq and + * time_tolerance variables, which represent the current frequency + * offset and maximum frequency tolerance. + */ +#define SHIFT_USEC 16 /* frequency offset scale (shift) */ +#define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC)) +#define PPM_SCALE_INV_SHIFT 19 +#define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \ + PPM_SCALE + 1) + +#define MAXPHASE 500000000l /* max phase error (ns) */ +#define MAXFREQ 500000 /* max frequency error (ns/s) */ +#define MAXFREQ_SCALED ((s64)MAXFREQ << NTP_SCALE_SHIFT) +#define MINSEC 256 /* min interval between updates (s) */ +#define MAXSEC 2048 /* max interval between updates (s) */ +#define NTP_PHASE_LIMIT ((MAXPHASE / NSEC_PER_USEC) << 5) /* beyond max. dispersion */ + +/* * kernel variables * Note: maximum error = NTP synch distance = dispersion + delay / 2; * estimated error = NTP dispersion. |
