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Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx4/en_clock.c')
-rw-r--r--drivers/net/ethernet/mellanox/mlx4/en_clock.c303
1 files changed, 303 insertions, 0 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
new file mode 100644
index 000000000..024788549
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
@@ -0,0 +1,303 @@
+/*
+ * Copyright (c) 2012 Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+#include <linux/mlx4/device.h>
+#include <linux/clocksource.h>
+
+#include "mlx4_en.h"
+
+/* mlx4_en_read_clock - read raw cycle counter (to be used by time counter)
+ */
+static u64 mlx4_en_read_clock(const struct cyclecounter *tc)
+{
+ struct mlx4_en_dev *mdev =
+ container_of(tc, struct mlx4_en_dev, cycles);
+ struct mlx4_dev *dev = mdev->dev;
+
+ return mlx4_read_clock(dev) & tc->mask;
+}
+
+u64 mlx4_en_get_cqe_ts(struct mlx4_cqe *cqe)
+{
+ u64 hi, lo;
+ struct mlx4_ts_cqe *ts_cqe = (struct mlx4_ts_cqe *)cqe;
+
+ lo = (u64)be16_to_cpu(ts_cqe->timestamp_lo);
+ hi = ((u64)be32_to_cpu(ts_cqe->timestamp_hi) + !lo) << 16;
+
+ return hi | lo;
+}
+
+void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
+ struct skb_shared_hwtstamps *hwts,
+ u64 timestamp)
+{
+ unsigned int seq;
+ u64 nsec;
+
+ do {
+ seq = read_seqbegin(&mdev->clock_lock);
+ nsec = timecounter_cyc2time(&mdev->clock, timestamp);
+ } while (read_seqretry(&mdev->clock_lock, seq));
+
+ 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");
+ }
+}
+
+#define MLX4_EN_WRAP_AROUND_SEC 10UL
+/* By scheduling the overflow check every 5 seconds, we have a reasonably
+ * good chance we wont miss a wrap around.
+ * TOTO: Use a timer instead of a work queue to increase the guarantee.
+ */
+#define MLX4_EN_OVERFLOW_PERIOD (MLX4_EN_WRAP_AROUND_SEC * HZ / 2)
+
+void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev)
+{
+ bool timeout = time_is_before_jiffies(mdev->last_overflow_check +
+ MLX4_EN_OVERFLOW_PERIOD);
+ unsigned long flags;
+
+ if (timeout) {
+ write_seqlock_irqsave(&mdev->clock_lock, flags);
+ timecounter_read(&mdev->clock);
+ write_sequnlock_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);
+
+ write_seqlock_irqsave(&mdev->clock_lock, flags);
+ timecounter_read(&mdev->clock);
+ mdev->cycles.mult = neg_adj ? mult - diff : mult + diff;
+ write_sequnlock_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;
+
+ write_seqlock_irqsave(&mdev->clock_lock, flags);
+ timecounter_adjtime(&mdev->clock, delta);
+ write_sequnlock_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 timespec64 *ts)
+{
+ struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
+ ptp_clock_info);
+ unsigned long flags;
+ u64 ns;
+
+ write_seqlock_irqsave(&mdev->clock_lock, flags);
+ ns = timecounter_read(&mdev->clock);
+ write_sequnlock_irqrestore(&mdev->clock_lock, flags);
+
+ *ts = ns_to_timespec64(ns);
+
+ 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 timespec64 *ts)
+{
+ struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
+ ptp_clock_info);
+ u64 ns = timespec64_to_ns(ts);
+ unsigned long flags;
+
+ /* reset the timecounter */
+ write_seqlock_irqsave(&mdev->clock_lock, flags);
+ timecounter_init(&mdev->clock, &mdev->cycles, ns);
+ write_sequnlock_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,
+ .n_pins = 0,
+ .pps = 0,
+ .adjfreq = mlx4_en_phc_adjfreq,
+ .adjtime = mlx4_en_phc_adjtime,
+ .gettime64 = mlx4_en_phc_gettime,
+ .settime64 = mlx4_en_phc_settime,
+ .enable = mlx4_en_phc_enable,
+};
+
+
+/* This function calculates the max shift that enables the user range
+ * of MLX4_EN_WRAP_AROUND_SEC values in the cycles register.
+ */
+static u32 freq_to_shift(u16 freq)
+{
+ u32 freq_khz = freq * 1000;
+ u64 max_val_cycles = freq_khz * 1000 * MLX4_EN_WRAP_AROUND_SEC;
+ u64 max_val_cycles_rounded = 1ULL << fls64(max_val_cycles - 1);
+ /* calculate max possible multiplier in order to fit in 64bit */
+ u64 max_mul = div64_u64(ULLONG_MAX, max_val_cycles_rounded);
+
+ /* This comes from the reverse of clocksource_khz2mult */
+ return ilog2(div_u64(max_mul * freq_khz, 1000000));
+}
+
+void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
+{
+ struct mlx4_dev *dev = mdev->dev;
+ unsigned long flags;
+
+ /* mlx4_en_init_timestamp is called for each netdev.
+ * mdev->ptp_clock is common for all ports, skip initialization if
+ * was done for other port.
+ */
+ if (mdev->ptp_clock)
+ return;
+
+ seqlock_init(&mdev->clock_lock);
+
+ memset(&mdev->cycles, 0, sizeof(mdev->cycles));
+ mdev->cycles.read = mlx4_en_read_clock;
+ mdev->cycles.mask = CLOCKSOURCE_MASK(48);
+ mdev->cycles.shift = freq_to_shift(dev->caps.hca_core_clock);
+ mdev->cycles.mult =
+ clocksource_khz2mult(1000 * dev->caps.hca_core_clock, mdev->cycles.shift);
+ mdev->nominal_c_mult = mdev->cycles.mult;
+
+ write_seqlock_irqsave(&mdev->clock_lock, flags);
+ timecounter_init(&mdev->clock, &mdev->cycles,
+ ktime_to_ns(ktime_get_real()));
+ write_sequnlock_irqrestore(&mdev->clock_lock, flags);
+
+ /* Configure the PHC */
+ mdev->ptp_clock_info = mlx4_en_ptp_clock_info;
+ snprintf(mdev->ptp_clock_info.name, 16, "mlx4 ptp");
+
+ 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 if (mdev->ptp_clock) {
+ mlx4_info(mdev, "registered PHC clock\n");
+ }
+
+}