From 10bc877c762339b8501a5b397137cf2f47cde575 Mon Sep 17 00:00:00 2001 From: Yangbo Lu Date: Thu, 12 Dec 2019 18:08:04 +0800 Subject: ptp_qoriq: check valid status before reading extts fifo For PTP timer supporting external trigger timestamp FIFO, there is a valid bit in TMR_STAT register indicating the timestamp is available. For PTP timer without FIFO, there is not TMR_STAT register. This patch is to check the valid bit for the FIFO before reading timestamp, and to avoid operating TMR_STAT register for PTP timer without the FIFO. Signed-off-by: Yangbo Lu Signed-off-by: David S. Miller --- drivers/ptp/ptp_qoriq.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/ptp/ptp_qoriq.c b/drivers/ptp/ptp_qoriq.c index a577218d1ab7..a3062cd4d174 100644 --- a/drivers/ptp/ptp_qoriq.c +++ b/drivers/ptp/ptp_qoriq.c @@ -81,7 +81,7 @@ static int extts_clean_up(struct ptp_qoriq *ptp_qoriq, int index, struct ptp_clock_event event; void __iomem *reg_etts_l; void __iomem *reg_etts_h; - u32 valid, stat, lo, hi; + u32 valid, lo, hi; switch (index) { case 0: @@ -101,6 +101,10 @@ static int extts_clean_up(struct ptp_qoriq *ptp_qoriq, int index, event.type = PTP_CLOCK_EXTTS; event.index = index; + if (ptp_qoriq->extts_fifo_support) + if (!(ptp_qoriq->read(®s->ctrl_regs->tmr_stat) & valid)) + return 0; + do { lo = ptp_qoriq->read(reg_etts_l); hi = ptp_qoriq->read(reg_etts_h); @@ -111,8 +115,9 @@ static int extts_clean_up(struct ptp_qoriq *ptp_qoriq, int index, ptp_clock_event(ptp_qoriq->clock, &event); } - stat = ptp_qoriq->read(®s->ctrl_regs->tmr_stat); - } while (ptp_qoriq->extts_fifo_support && (stat & valid)); + if (!ptp_qoriq->extts_fifo_support) + break; + } while (ptp_qoriq->read(®s->ctrl_regs->tmr_stat) & valid); return 0; } -- cgit v1.2.3