diff options
Diffstat (limited to 'drivers/ptp/ptp_ocp.c')
| -rw-r--r-- | drivers/ptp/ptp_ocp.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/drivers/ptp/ptp_ocp.c b/drivers/ptp/ptp_ocp.c index e7479b9b90cb..5feecaadde8e 100644 --- a/drivers/ptp/ptp_ocp.c +++ b/drivers/ptp/ptp_ocp.c @@ -1558,22 +1558,24 @@ ptp_ocp_watchdog(struct timer_list *t) static void ptp_ocp_estimate_pci_timing(struct ptp_ocp *bp) { - ktime_t start, end; - ktime_t delay; + ktime_t start, end, delay = U64_MAX; u32 ctrl; + int i; - ctrl = ioread32(&bp->reg->ctrl); - ctrl = OCP_CTRL_READ_TIME_REQ | OCP_CTRL_ENABLE; + for (i = 0; i < 3; i++) { + ctrl = ioread32(&bp->reg->ctrl); + ctrl = OCP_CTRL_READ_TIME_REQ | OCP_CTRL_ENABLE; - iowrite32(ctrl, &bp->reg->ctrl); + iowrite32(ctrl, &bp->reg->ctrl); - start = ktime_get_ns(); + start = ktime_get_raw_ns(); - ctrl = ioread32(&bp->reg->ctrl); + ctrl = ioread32(&bp->reg->ctrl); - end = ktime_get_ns(); + end = ktime_get_raw_ns(); - delay = end - start; + delay = min(delay, end - start); + } bp->ts_window_adjust = (delay >> 5) * 3; } |