#define FEC_T_INC_CORR_MASK 0x00007f00
#define FEC_T_INC_CORR_OFFSET 8
+#define FEC_T_CTRL_PINPER 0x00000080
+#define FEC_T_TF0_MASK 0x00000001
+#define FEC_T_TF0_OFFSET 0
+#define FEC_T_TF1_MASK 0x00000002
+#define FEC_T_TF1_OFFSET 1
+#define FEC_T_TF2_MASK 0x00000004
+#define FEC_T_TF2_OFFSET 2
+#define FEC_T_TF3_MASK 0x00000008
+#define FEC_T_TF3_OFFSET 3
+#define FEC_T_TDRE_MASK 0x00000001
+#define FEC_T_TDRE_OFFSET 0
+#define FEC_T_TMODE_MASK 0x0000003C
+#define FEC_T_TMODE_OFFSET 2
+#define FEC_T_TIE_MASK 0x00000040
+#define FEC_T_TIE_OFFSET 6
+#define FEC_T_TF_MASK 0x00000080
+#define FEC_T_TF_OFFSET 7
+
#define FEC_ATIME_CTRL 0x400
#define FEC_ATIME 0x404
#define FEC_ATIME_EVT_OFFSET 0x408
#define FEC_ATIME_INC 0x414
#define FEC_TS_TIMESTAMP 0x418
+#define FEC_TGSR 0x604
+#define FEC_TCSR(n) (0x608 + n * 0x08)
+#define FEC_TCCR(n) (0x60C + n * 0x08)
+#define MAX_TIMER_CHANNEL 3
+#define FEC_TMODE_TOGGLE 0x05
+#define FEC_HIGH_PULSE 0x0F
+
#define FEC_CC_MULT (1 << 31)
#define FEC_COUNTER_PERIOD (1 << 31)
+#define PPS_OUPUT_RELOAD_PERIOD NSEC_PER_SEC
+#define FEC_CHANNLE_0 0
+#define DEFAULT_PPS_CHANNEL FEC_CHANNLE_0
+
+/**
+ * fec_ptp_enable_pps
+ * @fep: the fec_enet_private structure handle
+ * @enable: enable the channel pps output
+ *
+ * This function enble the PPS ouput on the timer channel.
+ */
+static int fec_ptp_enable_pps(struct fec_enet_private *fep, uint enable)
+{
+ unsigned long flags;
+ u32 val, tempval;
+ int inc;
+ struct timespec ts;
+ u64 ns;
+ u32 remainder;
+ val = 0;
+
+ if (!(fep->hwts_tx_en || fep->hwts_rx_en)) {
+ dev_err(&fep->pdev->dev, "No ptp stack is running\n");
+ return -EINVAL;
+ }
+
+ if (fep->pps_enable == enable)
+ return 0;
+
+ fep->pps_channel = DEFAULT_PPS_CHANNEL;
+ fep->reload_period = PPS_OUPUT_RELOAD_PERIOD;
+ inc = fep->ptp_inc;
+
+ spin_lock_irqsave(&fep->tmreg_lock, flags);
+
+ if (enable) {
+ /* clear capture or output compare interrupt status if have.
+ */
+ writel(FEC_T_TF_MASK, fep->hwp + FEC_TCSR(fep->pps_channel));
+
+ /* It is recommended to doulbe check the TMODE field in the
+ * TCSR register to be cleared before the first compare counter
+ * is written into TCCR register. Just add a double check.
+ */
+ val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
+ do {
+ val &= ~(FEC_T_TMODE_MASK);
+ writel(val, fep->hwp + FEC_TCSR(fep->pps_channel));
+ val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
+ } while (val & FEC_T_TMODE_MASK);
+
+ /* Dummy read counter to update the counter */
+ timecounter_read(&fep->tc);
+ /* We want to find the first compare event in the next
+ * second point. So we need to know what the ptp time
+ * is now and how many nanoseconds is ahead to get next second.
+ * The remaining nanosecond ahead before the next second would be
+ * NSEC_PER_SEC - ts.tv_nsec. Add the remaining nanoseconds
+ * to current timer would be next second.
+ */
+ tempval = readl(fep->hwp + FEC_ATIME_CTRL);
+ tempval |= FEC_T_CTRL_CAPTURE;
+ writel(tempval, fep->hwp + FEC_ATIME_CTRL);
+
+ tempval = readl(fep->hwp + FEC_ATIME);
+ /* Convert the ptp local counter to 1588 timestamp */
+ ns = timecounter_cyc2time(&fep->tc, tempval);
+ ts.tv_sec = div_u64_rem(ns, 1000000000ULL, &remainder);
+ ts.tv_nsec = remainder;
+
+ /* The tempval is less than 3 seconds, and so val is less than
+ * 4 seconds. No overflow for 32bit calculation.
+ */
+ val = NSEC_PER_SEC - (u32)ts.tv_nsec + tempval;
+
+ /* Need to consider the situation that the current time is
+ * very close to the second point, which means NSEC_PER_SEC
+ * - ts.tv_nsec is close to be zero(For example 20ns); Since the timer
+ * is still running when we calculate the first compare event, it is
+ * possible that the remaining nanoseonds run out before the compare
+ * counter is calculated and written into TCCR register. To avoid
+ * this possibility, we will set the compare event to be the next
+ * of next second. The current setting is 31-bit timer and wrap
+ * around over 2 seconds. So it is okay to set the next of next
+ * seond for the timer.
+ */
+ val += NSEC_PER_SEC;
+
+ /* We add (2 * NSEC_PER_SEC - (u32)ts.tv_nsec) to current
+ * ptp counter, which maybe cause 32-bit wrap. Since the
+ * (NSEC_PER_SEC - (u32)ts.tv_nsec) is less than 2 second.
+ * We can ensure the wrap will not cause issue. If the offset
+ * is bigger than fep->cc.mask would be a error.
+ */
+ val &= fep->cc.mask;
+ writel(val, fep->hwp + FEC_TCCR(fep->pps_channel));
+
+ /* Calculate the second the compare event timestamp */
+ fep->next_counter = (val + fep->reload_period) & fep->cc.mask;
+
+ /* * Enable compare event when overflow */
+ val = readl(fep->hwp + FEC_ATIME_CTRL);
+ val |= FEC_T_CTRL_PINPER;
+ writel(val, fep->hwp + FEC_ATIME_CTRL);
+
+ /* Compare channel setting. */
+ val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
+ val |= (1 << FEC_T_TF_OFFSET | 1 << FEC_T_TIE_OFFSET);
+ val &= ~(1 << FEC_T_TDRE_OFFSET);
+ val &= ~(FEC_T_TMODE_MASK);
+ val |= (FEC_HIGH_PULSE << FEC_T_TMODE_OFFSET);
+ writel(val, fep->hwp + FEC_TCSR(fep->pps_channel));
+
+ /* Write the second compare event timestamp and calculate
+ * the third timestamp. Refer the TCCR register detail in the spec.
+ */
+ writel(fep->next_counter, fep->hwp + FEC_TCCR(fep->pps_channel));
+ fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask;
+ } else {
+ writel(0, fep->hwp + FEC_TCSR(fep->pps_channel));
+ }
+
+ fep->pps_enable = enable;
+ spin_unlock_irqrestore(&fep->tmreg_lock, flags);
+
+ return 0;
+}
+
/**
* fec_ptp_read - read raw cycle counter (to be used by time counter)
* @cc: the cyclecounter structure
static int fec_ptp_enable(struct ptp_clock_info *ptp,
struct ptp_clock_request *rq, int on)
{
+ struct fec_enet_private *fep =
+ container_of(ptp, struct fec_enet_private, ptp_caps);
+ int ret = 0;
+
+ if (rq->type == PTP_CLK_REQ_PPS) {
+ ret = fec_ptp_enable_pps(fep, on);
+
+ return ret;
+ }
return -EOPNOTSUPP;
}
fep->ptp_caps.n_ext_ts = 0;
fep->ptp_caps.n_per_out = 0;
fep->ptp_caps.n_pins = 0;
- fep->ptp_caps.pps = 0;
+ fep->ptp_caps.pps = 1;
fep->ptp_caps.adjfreq = fec_ptp_adjfreq;
fep->ptp_caps.adjtime = fec_ptp_adjtime;
fep->ptp_caps.gettime = fec_ptp_gettime;
schedule_delayed_work(&fep->time_keep, HZ);
}
+
+/**
+ * fec_ptp_check_pps_event
+ * @fep: the fec_enet_private structure handle
+ *
+ * This function check the pps event and reload the timer compare counter.
+ */
+uint fec_ptp_check_pps_event(struct fec_enet_private *fep)
+{
+ u32 val;
+ u8 channel = fep->pps_channel;
+ struct ptp_clock_event event;
+
+ val = readl(fep->hwp + FEC_TCSR(channel));
+ if (val & FEC_T_TF_MASK) {
+ /* Write the next next compare(not the next according the spec)
+ * value to the register
+ */
+ writel(fep->next_counter, fep->hwp + FEC_TCCR(channel));
+ do {
+ writel(val, fep->hwp + FEC_TCSR(channel));
+ } while (readl(fep->hwp + FEC_TCSR(channel)) & FEC_T_TF_MASK);
+
+ /* Update the counter; */
+ fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask;
+
+ event.type = PTP_CLOCK_PPS;
+ ptp_clock_event(fep->ptp_clock, &event);
+ return 1;
+ }
+
+ return 0;
+}
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