From f28460b229919387b2f97f3a688d0dd86cc819c9 Mon Sep 17 00:00:00 2001 From: Luwei Zhou Date: Fri, 10 Oct 2014 13:15:28 +0800 Subject: net: fec: ptp: Use the 31-bit ptp timer. When ptp switches from software adjustment to hardware ajustment, linux ptp can't converge. It is caused by the IP limit. Hardware adjustment logcial have issue when ptp counter runs over 0x80000000(31 bit counter). The internal IP reference manual already remove 32bit free-running count support. This patch replace the 32-bit PTP timer with 31-bit. Signed-off-by: Luwei Zhou Signed-off-by: Frank Li Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/fec_ptp.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c index cca3617a2321..8016bdd1995f 100644 --- a/drivers/net/ethernet/freescale/fec_ptp.c +++ b/drivers/net/ethernet/freescale/fec_ptp.c @@ -70,6 +70,7 @@ #define FEC_TS_TIMESTAMP 0x418 #define FEC_CC_MULT (1 << 31) +#define FEC_COUNTER_PERIOD (1 << 31) /** * fec_ptp_read - read raw cycle counter (to be used by time counter) * @cc: the cyclecounter structure @@ -113,14 +114,15 @@ void fec_ptp_start_cyclecounter(struct net_device *ndev) /* 1ns counter */ writel(inc << FEC_T_INC_OFFSET, fep->hwp + FEC_ATIME_INC); - /* use free running count */ - writel(0, fep->hwp + FEC_ATIME_EVT_PERIOD); + /* use 31-bit timer counter */ + writel(FEC_COUNTER_PERIOD, fep->hwp + FEC_ATIME_EVT_PERIOD); - writel(FEC_T_CTRL_ENABLE, fep->hwp + FEC_ATIME_CTRL); + writel(FEC_T_CTRL_ENABLE | FEC_T_CTRL_PERIOD_RST, + fep->hwp + FEC_ATIME_CTRL); memset(&fep->cc, 0, sizeof(fep->cc)); fep->cc.read = fec_ptp_read; - fep->cc.mask = CLOCKSOURCE_MASK(32); + fep->cc.mask = CLOCKSOURCE_MASK(31); fep->cc.shift = 31; fep->cc.mult = FEC_CC_MULT; -- cgit v1.2.3