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authorJacob Keller2014-05-28 09:21:47 +0200
committerJeff Kirsher2014-07-01 11:48:39 +0200
commita5a0fc0461c70047d7fd771499db1710e3630122 (patch)
tree473d939ff22fb69197c3ebd188bcd476e2b843e0 /drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
parentigb: bring link up when PHY is powered up (diff)
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ixgbe: change PTP NSECS_PER_SEC to IXGBE_PTP_PPS_HALF_SECOND
The PPS signal is not correct, as it generates a one half HZ clock signal, as it only generates one level change per second. To generate a full clock, we need two level changes per second. Also, change the name of the #define, in order to prevent confusion between it and NSEC_PER_SEC which is not guaranteed to be a 64bit value. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c')
-rw-r--r--drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c16
1 files changed, 9 insertions, 7 deletions
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
index 68f87ecb8a76..5fd4b5271f9a 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
@@ -98,9 +98,11 @@
#define IXGBE_OVERFLOW_PERIOD (HZ * 30)
#define IXGBE_PTP_TX_TIMEOUT (HZ * 15)
-#ifndef NSECS_PER_SEC
-#define NSECS_PER_SEC 1000000000ULL
-#endif
+/* half of a one second clock period, for use with PPS signal. We have to use
+ * this instead of something pre-defined like IXGBE_PTP_PPS_HALF_SECOND, in
+ * order to force at least 64bits of precision for shifting
+ */
+#define IXGBE_PTP_PPS_HALF_SECOND 500000000ULL
/**
* ixgbe_ptp_setup_sdp
@@ -146,8 +148,8 @@ static void ixgbe_ptp_setup_sdp(struct ixgbe_adapter *adapter)
IXGBE_TSAUXC_SDP0_INT);
/* clock period (or pulse length) */
- clktiml = (u32)(NSECS_PER_SEC << shift);
- clktimh = (u32)((NSECS_PER_SEC << shift) >> 32);
+ clktiml = (u32)(IXGBE_PTP_PPS_HALF_SECOND << shift);
+ clktimh = (u32)((IXGBE_PTP_PPS_HALF_SECOND << shift) >> 32);
/*
* Account for the cyclecounter wrap-around value by
@@ -158,8 +160,8 @@ static void ixgbe_ptp_setup_sdp(struct ixgbe_adapter *adapter)
clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;
ns = timecounter_cyc2time(&adapter->tc, clock_edge);
- div_u64_rem(ns, NSECS_PER_SEC, &rem);
- clock_edge += ((NSECS_PER_SEC - (u64)rem) << shift);
+ div_u64_rem(ns, IXGBE_PTP_PPS_HALF_SECOND, &rem);
+ clock_edge += ((IXGBE_PTP_PPS_HALF_SECOND - (u64)rem) << shift);
/* specify the initial clock start time */
trgttiml = (u32)clock_edge;