summaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/intel/igb/igb_ptp.c
diff options
context:
space:
mode:
authorMarcel Ziswiler <marcel.ziswiler@toradex.com>2019-12-18 22:52:20 +0100
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2019-12-18 22:52:20 +0100
commit1ddf624b0b268fdc0b80b1de618b98f8d117afea (patch)
tree3d3218332bcb34cb0afa01d6ad996058a3dbcb77 /drivers/net/ethernet/intel/igb/igb_ptp.c
parent6b774eec1f9d3064e9b33634dfa99d5666d0a73a (diff)
parentbfb9e5c03076a446b1f4f6a523ddc8d723c907a6 (diff)
Merge tag 'v4.14.159' into 4.14-2.0.x-imx
This is the 4.14.159 stable release Conflicts: arch/arm/Kconfig.debug arch/arm/boot/dts/imx7s.dtsi arch/arm/mach-imx/cpuidle-imx6sx.c drivers/crypto/caam/caamalg.c drivers/crypto/mxs-dcp.c drivers/dma/imx-sdma.c drivers/input/keyboard/imx_keypad.c drivers/net/can/flexcan.c drivers/net/can/rx-offload.c drivers/net/wireless/ath/ath10k/pci.c drivers/pci/dwc/pci-imx6.c drivers/spi/spi-fsl-lpspi.c drivers/usb/dwc3/gadget.c
Diffstat (limited to 'drivers/net/ethernet/intel/igb/igb_ptp.c')
-rw-r--r--drivers/net/ethernet/intel/igb/igb_ptp.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/net/ethernet/intel/igb/igb_ptp.c b/drivers/net/ethernet/intel/igb/igb_ptp.c
index 0746b19ec6d3..295d27f33104 100644
--- a/drivers/net/ethernet/intel/igb/igb_ptp.c
+++ b/drivers/net/ethernet/intel/igb/igb_ptp.c
@@ -65,9 +65,15 @@
*
* The 40 bit 82580 SYSTIM overflows every
* 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.
*/
-#define IGB_SYSTIM_OVERFLOW_PERIOD (HZ * 60 * 9)
+#define IGB_SYSTIM_OVERFLOW_PERIOD (HZ * 60 * 8)
#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)