diff options
Diffstat (limited to 'drivers/net/ethernet/renesas/ravb_ptp.c')
-rw-r--r-- | drivers/net/ethernet/renesas/ravb_ptp.c | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/drivers/net/ethernet/renesas/ravb_ptp.c b/drivers/net/ethernet/renesas/ravb_ptp.c new file mode 100644 index 000000000000..7a8ce920c49e --- /dev/null +++ b/drivers/net/ethernet/renesas/ravb_ptp.c @@ -0,0 +1,359 @@ +/* PTP 1588 clock using the Renesas Ethernet AVB + * + * Copyright (C) 2013-2015 Renesas Electronics Corporation + * Copyright (C) 2015 Renesas Solutions Corp. + * Copyright (C) 2015 Cogent Embedded, Inc. <source@cogentembedded.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include "ravb.h" + +static int ravb_ptp_tcr_request(struct ravb_private *priv, u32 request) +{ + struct net_device *ndev = priv->ndev; + int error; + + error = ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); + if (error) + return error; + + ravb_write(ndev, ravb_read(ndev, GCCR) | request, GCCR); + return ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); +} + +/* Caller must hold the lock */ +static int ravb_ptp_time_read(struct ravb_private *priv, struct timespec64 *ts) +{ + struct net_device *ndev = priv->ndev; + int error; + + error = ravb_ptp_tcr_request(priv, GCCR_TCR_CAPTURE); + if (error) + return error; + + ts->tv_nsec = ravb_read(ndev, GCT0); + ts->tv_sec = ravb_read(ndev, GCT1) | + ((s64)ravb_read(ndev, GCT2) << 32); + + return 0; +} + +/* Caller must hold the lock */ +static int ravb_ptp_time_write(struct ravb_private *priv, + const struct timespec64 *ts) +{ + struct net_device *ndev = priv->ndev; + int error; + u32 gccr; + + error = ravb_ptp_tcr_request(priv, GCCR_TCR_RESET); + if (error) + return error; + + gccr = ravb_read(ndev, GCCR); + if (gccr & GCCR_LTO) + return -EBUSY; + ravb_write(ndev, ts->tv_nsec, GTO0); + ravb_write(ndev, ts->tv_sec, GTO1); + ravb_write(ndev, (ts->tv_sec >> 32) & 0xffff, GTO2); + ravb_write(ndev, gccr | GCCR_LTO, GCCR); + + return 0; +} + +/* Caller must hold the lock */ +static int ravb_ptp_update_compare(struct ravb_private *priv, u32 ns) +{ + struct net_device *ndev = priv->ndev; + /* When the comparison value (GPTC.PTCV) is in range of + * [x-1 to x+1] (x is the configured increment value in + * GTI.TIV), it may happen that a comparison match is + * not detected when the timer wraps around. + */ + u32 gti_ns_plus_1 = (priv->ptp.current_addend >> 20) + 1; + u32 gccr; + + if (ns < gti_ns_plus_1) + ns = gti_ns_plus_1; + else if (ns > 0 - gti_ns_plus_1) + ns = 0 - gti_ns_plus_1; + + gccr = ravb_read(ndev, GCCR); + if (gccr & GCCR_LPTC) + return -EBUSY; + ravb_write(ndev, ns, GPTC); + ravb_write(ndev, gccr | GCCR_LPTC, GCCR); + + return 0; +} + +/* PTP clock operations */ +static int ravb_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) +{ + struct ravb_private *priv = container_of(ptp, struct ravb_private, + ptp.info); + struct net_device *ndev = priv->ndev; + unsigned long flags; + u32 diff, addend; + bool neg_adj = false; + u32 gccr; + + if (ppb < 0) { + neg_adj = true; + ppb = -ppb; + } + addend = priv->ptp.default_addend; + diff = div_u64((u64)addend * ppb, NSEC_PER_SEC); + + addend = neg_adj ? addend - diff : addend + diff; + + spin_lock_irqsave(&priv->lock, flags); + + priv->ptp.current_addend = addend; + + gccr = ravb_read(ndev, GCCR); + if (gccr & GCCR_LTI) { + spin_unlock_irqrestore(&priv->lock, flags); + return -EBUSY; + } + ravb_write(ndev, addend & GTI_TIV, GTI); + ravb_write(ndev, gccr | GCCR_LTI, GCCR); + + spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} + +static int ravb_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) +{ + struct ravb_private *priv = container_of(ptp, struct ravb_private, + ptp.info); + struct timespec64 ts; + unsigned long flags; + int error; + + spin_lock_irqsave(&priv->lock, flags); + error = ravb_ptp_time_read(priv, &ts); + if (!error) { + u64 now = ktime_to_ns(timespec64_to_ktime(ts)); + + ts = ns_to_timespec64(now + delta); + error = ravb_ptp_time_write(priv, &ts); + } + spin_unlock_irqrestore(&priv->lock, flags); + + return error; +} + +static int ravb_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts) +{ + struct ravb_private *priv = container_of(ptp, struct ravb_private, + ptp.info); + unsigned long flags; + int error; + + spin_lock_irqsave(&priv->lock, flags); + error = ravb_ptp_time_read(priv, ts); + spin_unlock_irqrestore(&priv->lock, flags); + + return error; +} + +static int ravb_ptp_settime64(struct ptp_clock_info *ptp, + const struct timespec64 *ts) +{ + struct ravb_private *priv = container_of(ptp, struct ravb_private, + ptp.info); + unsigned long flags; + int error; + + spin_lock_irqsave(&priv->lock, flags); + error = ravb_ptp_time_write(priv, ts); + spin_unlock_irqrestore(&priv->lock, flags); + + return error; +} + +static int ravb_ptp_extts(struct ptp_clock_info *ptp, + struct ptp_extts_request *req, int on) +{ + struct ravb_private *priv = container_of(ptp, struct ravb_private, + ptp.info); + struct net_device *ndev = priv->ndev; + unsigned long flags; + u32 gic; + + if (req->index) + return -EINVAL; + + if (priv->ptp.extts[req->index] == on) + return 0; + priv->ptp.extts[req->index] = on; + + spin_lock_irqsave(&priv->lock, flags); + gic = ravb_read(ndev, GIC); + if (on) + gic |= GIC_PTCE; + else + gic &= ~GIC_PTCE; + ravb_write(ndev, gic, GIC); + mmiowb(); + spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} + +static int ravb_ptp_perout(struct ptp_clock_info *ptp, + struct ptp_perout_request *req, int on) +{ + struct ravb_private *priv = container_of(ptp, struct ravb_private, + ptp.info); + struct net_device *ndev = priv->ndev; + struct ravb_ptp_perout *perout; + unsigned long flags; + int error = 0; + u32 gic; + + if (req->index) + return -EINVAL; + + if (on) { + u64 start_ns; + u64 period_ns; + + start_ns = req->start.sec * NSEC_PER_SEC + req->start.nsec; + period_ns = req->period.sec * NSEC_PER_SEC + req->period.nsec; + + if (start_ns > U32_MAX) { + netdev_warn(ndev, + "ptp: start value (nsec) is over limit. Maximum size of start is only 32 bits\n"); + return -ERANGE; + } + + if (period_ns > U32_MAX) { + netdev_warn(ndev, + "ptp: period value (nsec) is over limit. Maximum size of period is only 32 bits\n"); + return -ERANGE; + } + + spin_lock_irqsave(&priv->lock, flags); + + perout = &priv->ptp.perout[req->index]; + perout->target = (u32)start_ns; + perout->period = (u32)period_ns; + error = ravb_ptp_update_compare(priv, (u32)start_ns); + if (!error) { + /* Unmask interrupt */ + gic = ravb_read(ndev, GIC); + gic |= GIC_PTME; + ravb_write(ndev, gic, GIC); + } + } else { + spin_lock_irqsave(&priv->lock, flags); + + perout = &priv->ptp.perout[req->index]; + perout->period = 0; + + /* Mask interrupt */ + gic = ravb_read(ndev, GIC); + gic &= ~GIC_PTME; + ravb_write(ndev, gic, GIC); + } + mmiowb(); + spin_unlock_irqrestore(&priv->lock, flags); + + return error; +} + +static int ravb_ptp_enable(struct ptp_clock_info *ptp, + struct ptp_clock_request *req, int on) +{ + switch (req->type) { + case PTP_CLK_REQ_EXTTS: + return ravb_ptp_extts(ptp, &req->extts, on); + case PTP_CLK_REQ_PEROUT: + return ravb_ptp_perout(ptp, &req->perout, on); + default: + return -EOPNOTSUPP; + } +} + +static const struct ptp_clock_info ravb_ptp_info = { + .owner = THIS_MODULE, + .name = "ravb clock", + .max_adj = 50000000, + .n_ext_ts = N_EXT_TS, + .n_per_out = N_PER_OUT, + .adjfreq = ravb_ptp_adjfreq, + .adjtime = ravb_ptp_adjtime, + .gettime64 = ravb_ptp_gettime64, + .settime64 = ravb_ptp_settime64, + .enable = ravb_ptp_enable, +}; + +/* Caller must hold the lock */ +irqreturn_t ravb_ptp_interrupt(struct net_device *ndev) +{ + struct ravb_private *priv = netdev_priv(ndev); + u32 gis = ravb_read(ndev, GIS); + + gis &= ravb_read(ndev, GIC); + if (gis & GIS_PTCF) { + struct ptp_clock_event event; + + event.type = PTP_CLOCK_EXTTS; + event.index = 0; + event.timestamp = ravb_read(ndev, GCPT); + ptp_clock_event(priv->ptp.clock, &event); + } + if (gis & GIS_PTMF) { + struct ravb_ptp_perout *perout = priv->ptp.perout; + + if (perout->period) { + perout->target += perout->period; + ravb_ptp_update_compare(priv, perout->target); + } + } + + if (gis) { + ravb_write(ndev, ~gis, GIS); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) +{ + struct ravb_private *priv = netdev_priv(ndev); + unsigned long flags; + u32 gccr; + + priv->ptp.info = ravb_ptp_info; + + priv->ptp.default_addend = ravb_read(ndev, GTI); + priv->ptp.current_addend = priv->ptp.default_addend; + + spin_lock_irqsave(&priv->lock, flags); + ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); + gccr = ravb_read(ndev, GCCR) & ~GCCR_TCSS; + ravb_write(ndev, gccr | GCCR_TCSS_ADJGPTP, GCCR); + mmiowb(); + spin_unlock_irqrestore(&priv->lock, flags); + + priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); +} + +void ravb_ptp_stop(struct net_device *ndev) +{ + struct ravb_private *priv = netdev_priv(ndev); + + ravb_write(ndev, 0, GIC); + ravb_write(ndev, 0, GIS); + + ptp_clock_unregister(priv->ptp.clock); +} |