diff options
| author | Maarten Lankhorst <maarten.lankhorst@linux.intel.com> | 2018-11-29 16:12:27 +0100 |
|---|---|---|
| committer | Maarten Lankhorst <maarten.lankhorst@linux.intel.com> | 2018-11-29 16:12:50 +0100 |
| commit | 65ffc51aba406636a901b02067287d8535c02417 (patch) | |
| tree | 206de4631c3f7d61ea552e50bde2841c558c7812 /drivers/net/ethernet/intel/igb/igb_ptp.c | |
| parent | d7a86dffc280cb5a2a18975d46c7b9d89b025c7e (diff) | |
| parent | 1ec28f8b8ada4e4f77d1af006a3a474f4f83b8e3 (diff) | |
Merge remote-tracking branch 'drm/drm-next' into drm-misc-next
Requested by Boris Brezillon for some vc4 fixes that are needed for future vc4 work.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/igb/igb_ptp.c')
| -rw-r--r-- | drivers/net/ethernet/intel/igb/igb_ptp.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/drivers/net/ethernet/intel/igb/igb_ptp.c b/drivers/net/ethernet/intel/igb/igb_ptp.c index 29ced6b74d36..2b95dc9c7a6a 100644 --- a/drivers/net/ethernet/intel/igb/igb_ptp.c +++ b/drivers/net/ethernet/intel/igb/igb_ptp.c @@ -53,13 +53,15 @@ * 2^40 * 10^-9 / 60 = 18.3 minutes. * * SYSTIM is converted to real time using a timecounter. As - * timecounter_cyc2time() allows old timestamps, the timecounter - * needs to be updated at least once per half of the SYSTIM interval. - * Scheduling of delayed work is not very accurate, so we aim for 8 - * minutes to be sure the actual interval is shorter than 9.16 minutes. + * timecounter_cyc2time() allows old timestamps, the timecounter needs + * to be updated at least once per half of the SYSTIM interval. + * Scheduling of delayed work is not very accurate, and also the NIC + * clock can be adjusted to run up to 6% faster and the system clock + * up to 10% slower, so we aim for 6 minutes to be sure the actual + * interval in the NIC time is shorter than 9.16 minutes. */ -#define IGB_SYSTIM_OVERFLOW_PERIOD (HZ * 60 * 8) +#define IGB_SYSTIM_OVERFLOW_PERIOD (HZ * 60 * 6) #define IGB_PTP_TX_TIMEOUT (HZ * 15) #define INCPERIOD_82576 BIT(E1000_TIMINCA_16NS_SHIFT) #define INCVALUE_82576_MASK GENMASK(E1000_TIMINCA_16NS_SHIFT - 1, 0) |