From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Bohrer Subject: Re: [PATCH net-next 1/2] mlx4_en: Add PTP hardware clock Date: Tue, 17 Dec 2013 15:46:15 -0600 Message-ID: <20131217214615.GD8693@sbohrermbp13-local.rgmadvisors.com> References: <1387312359-9476-1-git-send-email-shawn.bohrer@gmail.com> <1387312359-9476-2-git-send-email-shawn.bohrer@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "David S. Miller" , Or Gerlitz , Amir Vadai , Richard Cochran , "netdev@vger.kernel.org" , tomk@rgmadvisors.com, Hadar Hen Zion , Shawn Bohrer To: Or Gerlitz Return-path: Received: from mail-qe0-f51.google.com ([209.85.128.51]:56578 "EHLO mail-qe0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752129Ab3LQVqW (ORCPT ); Tue, 17 Dec 2013 16:46:22 -0500 Received: by mail-qe0-f51.google.com with SMTP id 1so5701088qee.24 for ; Tue, 17 Dec 2013 13:46:20 -0800 (PST) Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Tue, Dec 17, 2013 at 11:04:48PM +0200, Or Gerlitz wrote: > On Tue, Dec 17, 2013 at 10:32 PM, Shawn Bohrer wrote: > > From: Shawn Bohrer > > > > This adds a PHC to the mlx4_en driver. The code is largely based off of > > the e1000e driver (drivers/net/ethernet/intel/e1000e/ptp.c) which seemed > > very similar. > > > > This driver has been tested with both Documentation/ptp/testptp and the > > linuxptp project (http://linuxptp.sourceforge.net/) and appears to work > > on a Mellanox ConnectX-3 card. > > so this is V3 -- and what are the V2 --> V3 changes? Sorry, here is the evolution of this patch: v2: * Implemented mlx4_en_phc_adjfreq() in software. * Protected timecounter with a spinlock * Set the phc_index in mlx4_en_get_ts_info() * Use a hard-coded ptp_clock_info.name v3: is code identical to v2. I simply finished testing it with linuxptp, cleaned up the commit description a little and sent to davem. > > > > Signed-off-by: Shawn Bohrer > > --- > > drivers/net/ethernet/mellanox/mlx4/en_clock.c | 192 ++++++++++++++++++++++- > > drivers/net/ethernet/mellanox/mlx4/en_ethtool.c | 3 + > > drivers/net/ethernet/mellanox/mlx4/en_main.c | 3 + > > drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 6 + > > 4 files changed, 196 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c > > index fd64410..9b0d515 100644 > > --- a/drivers/net/ethernet/mellanox/mlx4/en_clock.c > > +++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c > > @@ -103,17 +103,187 @@ void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev, > > struct skb_shared_hwtstamps *hwts, > > u64 timestamp) > > { > > + unsigned long flags; > > u64 nsec; > > > > + spin_lock_irqsave(&mdev->clock_lock, flags); > > nsec = timecounter_cyc2time(&mdev->clock, timestamp); > > + spin_unlock_irqrestore(&mdev->clock_lock, flags); > > > > memset(hwts, 0, sizeof(struct skb_shared_hwtstamps)); > > hwts->hwtstamp = ns_to_ktime(nsec); > > } > > > > +/** > > + * mlx4_en_remove_timestamp - disable PTP device > > + * @mdev: board private structure > > + * > > + * Stop the PTP support. > > + **/ > > +void mlx4_en_remove_timestamp(struct mlx4_en_dev *mdev) > > +{ > > + if (mdev->ptp_clock) { > > + ptp_clock_unregister(mdev->ptp_clock); > > + mdev->ptp_clock = NULL; > > + mlx4_info(mdev, "removed PHC\n"); > > + } > > +} > > + > > +void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev) > > +{ > > + bool timeout = time_is_before_jiffies(mdev->last_overflow_check + > > + mdev->overflow_period); > > + unsigned long flags; > > + > > + if (timeout) { > > + spin_lock_irqsave(&mdev->clock_lock, flags); > > + timecounter_read(&mdev->clock); > > + spin_unlock_irqrestore(&mdev->clock_lock, flags); > > + mdev->last_overflow_check = jiffies; > > + } > > +} > > + > > +/** > > + * mlx4_en_phc_adjfreq - adjust the frequency of the hardware clock > > + * @ptp: ptp clock structure > > + * @delta: Desired frequency change in parts per billion > > + * > > + * Adjust the frequency of the PHC cycle counter by the indicated delta from > > + * the base frequency. > > + **/ > > +static int mlx4_en_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta) > > +{ > > + u64 adj; > > + u32 diff, mult; > > + int neg_adj = 0; > > + unsigned long flags; > > + struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev, > > + ptp_clock_info); > > + > > + if (delta < 0) { > > + neg_adj = 1; > > + delta = -delta; > > + } > > + mult = mdev->nominal_c_mult; > > + adj = mult; > > + adj *= delta; > > + diff = div_u64(adj, 1000000000ULL); > > + > > + spin_lock_irqsave(&mdev->clock_lock, flags); > > + timecounter_read(&mdev->clock); > > + mdev->cycles.mult = neg_adj ? mult - diff : mult + diff; > > + spin_unlock_irqrestore(&mdev->clock_lock, flags); > > + > > + return 0; > > +} > > + > > +/** > > + * mlx4_en_phc_adjtime - Shift the time of the hardware clock > > + * @ptp: ptp clock structure > > + * @delta: Desired change in nanoseconds > > + * > > + * Adjust the timer by resetting the timecounter structure. > > + **/ > > +static int mlx4_en_phc_adjtime(struct ptp_clock_info *ptp, s64 delta) > > +{ > > + struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev, > > + ptp_clock_info); > > + unsigned long flags; > > + s64 now; > > + > > + spin_lock_irqsave(&mdev->clock_lock, flags); > > + now = timecounter_read(&mdev->clock); > > + now += delta; > > + timecounter_init(&mdev->clock, &mdev->cycles, now); > > + spin_unlock_irqrestore(&mdev->clock_lock, flags); > > + > > + return 0; > > +} > > + > > +/** > > + * mlx4_en_phc_gettime - Reads the current time from the hardware clock > > + * @ptp: ptp clock structure > > + * @ts: timespec structure to hold the current time value > > + * > > + * Read the timecounter and return the correct value in ns after converting > > + * it into a struct timespec. > > + **/ > > +static int mlx4_en_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts) > > +{ > > + struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev, > > + ptp_clock_info); > > + unsigned long flags; > > + u32 remainder; > > + u64 ns; > > + > > + spin_lock_irqsave(&mdev->clock_lock, flags); > > + ns = timecounter_read(&mdev->clock); > > + spin_unlock_irqrestore(&mdev->clock_lock, flags); > > + > > + ts->tv_sec = div_u64_rem(ns, NSEC_PER_SEC, &remainder); > > + ts->tv_nsec = remainder; > > + > > + return 0; > > +} > > + > > +/** > > + * mlx4_en_phc_settime - Set the current time on the hardware clock > > + * @ptp: ptp clock structure > > + * @ts: timespec containing the new time for the cycle counter > > + * > > + * Reset the timecounter to use a new base value instead of the kernel > > + * wall timer value. > > + **/ > > +static int mlx4_en_phc_settime(struct ptp_clock_info *ptp, > > + const struct timespec *ts) > > +{ > > + struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev, > > + ptp_clock_info); > > + u64 ns = timespec_to_ns(ts); > > + unsigned long flags; > > + > > + /* reset the timecounter */ > > + spin_lock_irqsave(&mdev->clock_lock, flags); > > + timecounter_init(&mdev->clock, &mdev->cycles, ns); > > + spin_unlock_irqrestore(&mdev->clock_lock, flags); > > + > > + return 0; > > +} > > + > > +/** > > + * mlx4_en_phc_enable - enable or disable an ancillary feature > > + * @ptp: ptp clock structure > > + * @request: Desired resource to enable or disable > > + * @on: Caller passes one to enable or zero to disable > > + * > > + * Enable (or disable) ancillary features of the PHC subsystem. > > + * Currently, no ancillary features are supported. > > + **/ > > +static int mlx4_en_phc_enable(struct ptp_clock_info __always_unused *ptp, > > + struct ptp_clock_request __always_unused *request, > > + int __always_unused on) > > +{ > > + return -EOPNOTSUPP; > > +} > > + > > +static const struct ptp_clock_info mlx4_en_ptp_clock_info = { > > + .owner = THIS_MODULE, > > + .max_adj = 100000000, > > + .n_alarm = 0, > > + .n_ext_ts = 0, > > + .n_per_out = 0, > > + .pps = 0, > > + .adjfreq = mlx4_en_phc_adjfreq, > > + .adjtime = mlx4_en_phc_adjtime, > > + .gettime = mlx4_en_phc_gettime, > > + .settime = mlx4_en_phc_settime, > > + .enable = mlx4_en_phc_enable, > > +}; > > + > > void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev) > > { > > struct mlx4_dev *dev = mdev->dev; > > + unsigned long flags; > > u64 ns; > > > > memset(&mdev->cycles, 0, sizeof(mdev->cycles)); > > @@ -127,9 +297,12 @@ void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev) > > mdev->cycles.shift = 14; > > mdev->cycles.mult = > > clocksource_khz2mult(1000 * dev->caps.hca_core_clock, mdev->cycles.shift); > > + mdev->nominal_c_mult = mdev->cycles.mult; > > > > + spin_lock_irqsave(&mdev->clock_lock, flags); > > timecounter_init(&mdev->clock, &mdev->cycles, > > ktime_to_ns(ktime_get_real())); > > + spin_unlock_irqrestore(&mdev->clock_lock, flags); > > > > /* Calculate period in seconds to call the overflow watchdog - to make > > * sure counter is checked at least once every wrap around. > > @@ -137,15 +310,18 @@ void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev) > > ns = cyclecounter_cyc2ns(&mdev->cycles, mdev->cycles.mask); > > do_div(ns, NSEC_PER_SEC / 2 / HZ); > > mdev->overflow_period = ns; > > -} > > > > -void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev) > > -{ > > - bool timeout = time_is_before_jiffies(mdev->last_overflow_check + > > - mdev->overflow_period); > > + /* Configure the PHC */ > > + mdev->ptp_clock_info = mlx4_en_ptp_clock_info; > > + snprintf(mdev->ptp_clock_info.name, 16, "mlx4 ptp"); > > > > - if (timeout) { > > - timecounter_read(&mdev->clock); > > - mdev->last_overflow_check = jiffies; > > + mdev->ptp_clock = ptp_clock_register(&mdev->ptp_clock_info, > > + &mdev->pdev->dev); > > + if (IS_ERR(mdev->ptp_clock)) { > > + mdev->ptp_clock = NULL; > > + mlx4_err(mdev, "ptp_clock_register failed\n"); > > + } else { > > + mlx4_info(mdev, "registered PHC clock\n"); > > } > > + > > } > > diff --git a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c > > index 0596f9f..3e8d336 100644 > > --- a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c > > +++ b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c > > @@ -1193,6 +1193,9 @@ static int mlx4_en_get_ts_info(struct net_device *dev, > > info->rx_filters = > > (1 << HWTSTAMP_FILTER_NONE) | > > (1 << HWTSTAMP_FILTER_ALL); > > + > > + if (mdev->ptp_clock) > > + info->phc_index = ptp_clock_index(mdev->ptp_clock); > > } > > > > return ret; > > diff --git a/drivers/net/ethernet/mellanox/mlx4/en_main.c b/drivers/net/ethernet/mellanox/mlx4/en_main.c > > index 0d087b0..6268057 100644 > > --- a/drivers/net/ethernet/mellanox/mlx4/en_main.c > > +++ b/drivers/net/ethernet/mellanox/mlx4/en_main.c > > @@ -196,6 +196,9 @@ static void mlx4_en_remove(struct mlx4_dev *dev, void *endev_ptr) > > if (mdev->pndev[i]) > > mlx4_en_destroy_netdev(mdev->pndev[i]); > > > > + if (mdev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_TS) > > + mlx4_en_remove_timestamp(mdev); > > + > > flush_workqueue(mdev->workqueue); > > destroy_workqueue(mdev->workqueue); > > (void) mlx4_mr_free(dev, &mdev->mr); > > diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h > > index f3758de..2b4083f 100644 > > --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h > > +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h > > @@ -45,6 +45,7 @@ > > #include > > #endif > > #include > > +#include > > > > #include > > #include > > @@ -373,10 +374,14 @@ struct mlx4_en_dev { > > u32 priv_pdn; > > spinlock_t uar_lock; > > u8 mac_removed[MLX4_MAX_PORTS + 1]; > > + spinlock_t clock_lock; > > + u32 nominal_c_mult; > > struct cyclecounter cycles; > > struct timecounter clock; > > unsigned long last_overflow_check; > > unsigned long overflow_period; > > + struct ptp_clock *ptp_clock; > > + struct ptp_clock_info ptp_clock_info; > > }; > > > > > > @@ -786,6 +791,7 @@ void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev, > > struct skb_shared_hwtstamps *hwts, > > u64 timestamp); > > void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev); > > +void mlx4_en_remove_timestamp(struct mlx4_en_dev *mdev); > > int mlx4_en_timestamp_config(struct net_device *dev, > > int tx_type, > > int rx_filter); > > -- > > 1.7.7.6 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe netdev" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html