diff options
Diffstat (limited to 'drivers/net/ethernet/freescale/fec_ptp.c')
| -rw-r--r-- | drivers/net/ethernet/freescale/fec_ptp.c | 277 |
1 files changed, 260 insertions, 17 deletions
diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c index cca3617a2321..992c8c3db553 100644 --- a/drivers/net/ethernet/freescale/fec_ptp.c +++ b/drivers/net/ethernet/freescale/fec_ptp.c @@ -61,6 +61,24 @@ #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 @@ -69,7 +87,143 @@ #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 @@ -82,12 +236,17 @@ static cycle_t fec_ptp_read(const struct cyclecounter *cc) { struct fec_enet_private *fep = container_of(cc, struct fec_enet_private, cc); + const struct platform_device_id *id_entry = + platform_get_device_id(fep->pdev); u32 tempval; tempval = readl(fep->hwp + FEC_ATIME_CTRL); tempval |= FEC_T_CTRL_CAPTURE; writel(tempval, fep->hwp + FEC_ATIME_CTRL); + if (id_entry->driver_data & FEC_QUIRK_BUG_CAPTURE) + udelay(1); + return readl(fep->hwp + FEC_ATIME); } @@ -113,14 +272,15 @@ 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; @@ -143,32 +303,59 @@ void fec_ptp_start_cyclecounter(struct net_device *ndev) */ static int fec_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) { - u64 diff; unsigned long flags; int neg_adj = 0; - u32 mult = FEC_CC_MULT; + u32 i, tmp; + u32 corr_inc, corr_period; + u32 corr_ns; + u64 lhs, rhs; struct fec_enet_private *fep = container_of(ptp, struct fec_enet_private, ptp_caps); + if (ppb == 0) + return 0; + if (ppb < 0) { ppb = -ppb; neg_adj = 1; } - diff = mult; - diff *= ppb; - diff = div_u64(diff, 1000000000ULL); + /* In theory, corr_inc/corr_period = ppb/NSEC_PER_SEC; + * Try to find the corr_inc between 1 to fep->ptp_inc to + * meet adjustment requirement. + */ + lhs = NSEC_PER_SEC; + rhs = (u64)ppb * (u64)fep->ptp_inc; + for (i = 1; i <= fep->ptp_inc; i++) { + if (lhs >= rhs) { + corr_inc = i; + corr_period = div_u64(lhs, rhs); + break; + } + lhs += NSEC_PER_SEC; + } + /* Not found? Set it to high value - double speed + * correct in every clock step. + */ + if (i > fep->ptp_inc) { + corr_inc = fep->ptp_inc; + corr_period = 1; + } + + if (neg_adj) + corr_ns = fep->ptp_inc - corr_inc; + else + corr_ns = fep->ptp_inc + corr_inc; spin_lock_irqsave(&fep->tmreg_lock, flags); - /* - * dummy read to set cycle_last in tc to now. - * So use adjusted mult to calculate when next call - * timercounter_read. - */ - timecounter_read(&fep->tc); - fep->cc.mult = neg_adj ? mult - diff : mult + diff; + tmp = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_MASK; + tmp |= corr_ns << FEC_T_INC_CORR_OFFSET; + writel(tmp, fep->hwp + FEC_ATIME_INC); + writel(corr_period, fep->hwp + FEC_ATIME_CORR); + /* dummy read to update the timer. */ + timecounter_read(&fep->tc); spin_unlock_irqrestore(&fep->tmreg_lock, flags); @@ -188,12 +375,19 @@ static int fec_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) container_of(ptp, struct fec_enet_private, ptp_caps); unsigned long flags; u64 now; + u32 counter; spin_lock_irqsave(&fep->tmreg_lock, flags); now = timecounter_read(&fep->tc); now += delta; + /* Get the timer value based on adjusted timestamp. + * Update the counter with the masked value. + */ + counter = now & fep->cc.mask; + writel(counter, fep->hwp + FEC_ATIME); + /* reset the timecounter */ timecounter_init(&fep->tc, &fep->cc, now); @@ -244,6 +438,7 @@ static int fec_ptp_settime(struct ptp_clock_info *ptp, u64 ns; unsigned long flags; + u32 counter; mutex_lock(&fep->ptp_clk_mutex); /* Check the ptp clock */ @@ -254,8 +449,13 @@ static int fec_ptp_settime(struct ptp_clock_info *ptp, ns = ts->tv_sec * 1000000000ULL; ns += ts->tv_nsec; + /* Get the timer value based on timestamp. + * Update the counter with the masked value. + */ + counter = ns & fep->cc.mask; spin_lock_irqsave(&fep->tmreg_lock, flags); + writel(counter, fep->hwp + FEC_ATIME); timecounter_init(&fep->tc, &fep->cc, ns); spin_unlock_irqrestore(&fep->tmreg_lock, flags); mutex_unlock(&fep->ptp_clk_mutex); @@ -272,6 +472,15 @@ static int fec_ptp_settime(struct ptp_clock_info *ptp, 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; } @@ -386,7 +595,7 @@ void fec_ptp_init(struct platform_device *pdev) 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; @@ -394,6 +603,7 @@ void fec_ptp_init(struct platform_device *pdev) fep->ptp_caps.enable = fec_ptp_enable; fep->cycle_speed = clk_get_rate(fep->clk_ptp); + fep->ptp_inc = NSEC_PER_SEC / fep->cycle_speed; spin_lock_init(&fep->tmreg_lock); @@ -409,3 +619,36 @@ void fec_ptp_init(struct platform_device *pdev) 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; +} |