linux/drivers/net/ethernet/mellanox/mlx4/en_clock.c

/*
 * 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)
{ … }

u64 mlx4_en_get_cqe_ts(struct mlx4_cqe *cqe)
{ … }

u64 mlx4_en_get_hwtstamp(struct mlx4_en_dev *mdev, u64 timestamp)
{ … }

void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
			    struct skb_shared_hwtstamps *hwts,
			    u64 timestamp)
{ … }

/**
 * 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)
{ … }

#define MLX4_EN_WRAP_AROUND_SEC …
/* By scheduling the overflow check every 5 seconds, we have a reasonably
 * good chance we won't miss a wrap around.
 * TODO: Use a timer instead of a work queue to increase the guarantee.
 */
#define MLX4_EN_OVERFLOW_PERIOD …

void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev)
{ … }

/**
 * mlx4_en_phc_adjfine - adjust the frequency of the hardware clock
 * @ptp: ptp clock structure
 * @scaled_ppm: Desired frequency change in scaled parts per million
 *
 * Adjust the frequency of the PHC cycle counter by the indicated scaled_ppm
 * from the base frequency.
 *
 * Scaled parts per million is ppm with a 16-bit binary fractional field.
 **/
static int mlx4_en_phc_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

static const struct ptp_clock_info mlx4_en_ptp_clock_info = …;


/* 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)
{ … }

void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
{ … }