drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*******************************************************************************
   PTP 1588 clock using the STMMAC.

   Copyright (C) 2013  Vayavya Labs Pvt Ltd


   Author: Rayagond Kokatanur <rayagond@vayavyalabs.com>
 *******************************************************************************/
 #include "stmmac.h"
 #include "stmmac_ptp.h"
 #include "dwmac4.h"

 /**
  * stmmac_adjust_freq
  *
  * @ptp: pointer to ptp_clock_info structure
  * @scaled_ppm: desired period change in scaled parts per million
  *
  * Description: this function will adjust the frequency of hardware clock.
  *
  * Scaled parts per million is ppm with a 16-bit binary fractional field.
  */
 static int stmmac_adjust_freq(struct ptp_clock_info *ptp, long scaled_ppm)
 {
 	struct stmmac_priv *priv =
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	unsigned long flags;
 	u32 addend;

 	addend = adjust_by_scaled_ppm(priv->default_addend, scaled_ppm);

 	write_lock_irqsave(&priv->ptp_lock, flags);
 	stmmac_config_addend(priv, priv->ptpaddr, addend);
 	write_unlock_irqrestore(&priv->ptp_lock, flags);

 	return 0;
 }

 /**
  * stmmac_adjust_time
  *
  * @ptp: pointer to ptp_clock_info structure
  * @delta: desired change in nanoseconds
  *
  * Description: this function will shift/adjust the hardware clock time.
  */
 static int stmmac_adjust_time(struct ptp_clock_info *ptp, s64 delta)
 {
 	struct stmmac_priv *priv =
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	unsigned long flags;
 	u32 sec, nsec;
 	u32 quotient, reminder;
 	int neg_adj = 0;
 	bool xmac, est_rst = false;
 	int ret;

 	xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;

 	if (delta < 0) {
 		neg_adj = 1;
 		delta = -delta;
 	}

 	quotient = div_u64_rem(delta, 1000000000ULL, &reminder);
 	sec = quotient;
 	nsec = reminder;

 	/* If EST is enabled, disabled it before adjust ptp time. */
 	if (priv->est && priv->est->enable) {
 		est_rst = true;
 		mutex_lock(&priv->est_lock);
 		priv->est->enable = false;
 		stmmac_est_configure(priv, priv, priv->est,
 				     priv->plat->clk_ptp_rate);
 		mutex_unlock(&priv->est_lock);
 	}

 	write_lock_irqsave(&priv->ptp_lock, flags);
 	stmmac_adjust_systime(priv, priv->ptpaddr, sec, nsec, neg_adj, xmac);
 	write_unlock_irqrestore(&priv->ptp_lock, flags);

 	/* Calculate new basetime and re-configured EST after PTP time adjust. */
 	if (est_rst) {
 		struct timespec64 current_time, time;
 		ktime_t current_time_ns, basetime;
 		u64 cycle_time;

 		mutex_lock(&priv->est_lock);
 		priv->ptp_clock_ops.gettime64(&priv->ptp_clock_ops, &current_time);
 		current_time_ns = timespec64_to_ktime(current_time);
 		time.tv_nsec = priv->est->btr_reserve[0];
 		time.tv_sec = priv->est->btr_reserve[1];
 		basetime = timespec64_to_ktime(time);
 		cycle_time = (u64)priv->est->ctr[1] * NSEC_PER_SEC +
 			     priv->est->ctr[0];
 		time = stmmac_calc_tas_basetime(basetime,
 						current_time_ns,
 						cycle_time);

 		priv->est->btr[0] = (u32)time.tv_nsec;
 		priv->est->btr[1] = (u32)time.tv_sec;
 		priv->est->enable = true;
 		ret = stmmac_est_configure(priv, priv, priv->est,
 					   priv->plat->clk_ptp_rate);
 		mutex_unlock(&priv->est_lock);
 		if (ret)
 			netdev_err(priv->dev, "failed to configure EST\n");
 	}

 	return 0;
 }

 /**
  * stmmac_get_time
  *
  * @ptp: pointer to ptp_clock_info structure
  * @ts: pointer to hold time/result
  *
  * Description: this function will read the current time from the
  * hardware clock and store it in @ts.
  */
 static int stmmac_get_time(struct ptp_clock_info *ptp, struct timespec64 *ts)
 {
 	struct stmmac_priv *priv =
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	unsigned long flags;
 	u64 ns = 0;

 	read_lock_irqsave(&priv->ptp_lock, flags);
 	stmmac_get_systime(priv, priv->ptpaddr, &ns);
 	read_unlock_irqrestore(&priv->ptp_lock, flags);

 	*ts = ns_to_timespec64(ns);

 	return 0;
 }

 /**
  * stmmac_set_time
  *
  * @ptp: pointer to ptp_clock_info structure
  * @ts: time value to set
  *
  * Description: this function will set the current time on the
  * hardware clock.
  */
 static int stmmac_set_time(struct ptp_clock_info *ptp,
 			   const struct timespec64 *ts)
 {
 	struct stmmac_priv *priv =
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	unsigned long flags;

 	write_lock_irqsave(&priv->ptp_lock, flags);
 	stmmac_init_systime(priv, priv->ptpaddr, ts->tv_sec, ts->tv_nsec);
 	write_unlock_irqrestore(&priv->ptp_lock, flags);

 	return 0;
 }

 static int stmmac_enable(struct ptp_clock_info *ptp,
 			 struct ptp_clock_request *rq, int on)
 {
 	struct stmmac_priv *priv =
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	void __iomem *ptpaddr = priv->ptpaddr;
 	struct stmmac_pps_cfg *cfg;
 	int ret = -EOPNOTSUPP;
 	unsigned long flags;
 	u32 acr_value;

 	switch (rq->type) {
 	case PTP_CLK_REQ_PEROUT:
 		/* Reject requests with unsupported flags */
 		if (rq->perout.flags)
 			return -EOPNOTSUPP;

 		cfg = &priv->pps[rq->perout.index];

 		cfg->start.tv_sec = rq->perout.start.sec;
 		cfg->start.tv_nsec = rq->perout.start.nsec;
 		cfg->period.tv_sec = rq->perout.period.sec;
 		cfg->period.tv_nsec = rq->perout.period.nsec;

 		write_lock_irqsave(&priv->ptp_lock, flags);
 		ret = stmmac_flex_pps_config(priv, priv->ioaddr,
 					     rq->perout.index, cfg, on,
 					     priv->sub_second_inc,
 					     priv->systime_flags);
 		write_unlock_irqrestore(&priv->ptp_lock, flags);
 		break;
 	case PTP_CLK_REQ_EXTTS: {
 		u8 channel;

 		mutex_lock(&priv->aux_ts_lock);
 		acr_value = readl(ptpaddr + PTP_ACR);
 		channel = ilog2(FIELD_GET(PTP_ACR_MASK, acr_value));
 		acr_value &= ~PTP_ACR_MASK;

 		if (on) {
 			if (FIELD_GET(PTP_ACR_MASK, acr_value)) {
 				netdev_err(priv->dev,
 					   "Cannot enable auxiliary snapshot %d as auxiliary snapshot %d is already enabled",
 					rq->extts.index, channel);
 				mutex_unlock(&priv->aux_ts_lock);
 				return -EBUSY;
 			}

 			priv->plat->flags |= STMMAC_FLAG_EXT_SNAPSHOT_EN;

 			/* Enable External snapshot trigger */
 			acr_value |= PTP_ACR_ATSEN(rq->extts.index);
 			acr_value |= PTP_ACR_ATSFC;
 		} else {
 			priv->plat->flags &= ~STMMAC_FLAG_EXT_SNAPSHOT_EN;
 		}
 		netdev_dbg(priv->dev, "Auxiliary Snapshot %d %s.\n",
 			   rq->extts.index, on ? "enabled" : "disabled");
 		writel(acr_value, ptpaddr + PTP_ACR);
 		mutex_unlock(&priv->aux_ts_lock);
 		/* wait for auxts fifo clear to finish */
 		ret = readl_poll_timeout(ptpaddr + PTP_ACR, acr_value,
 					 !(acr_value & PTP_ACR_ATSFC),
 					 10, 10000);
 		break;
 	}

 	default:
 		break;
 	}

 	return ret;
 }

 /**
  * stmmac_get_syncdevicetime
  * @device: current device time
  * @system: system counter value read synchronously with device time
  * @ctx: context provided by timekeeping code
  * Description: Read device and system clock simultaneously and return the
  * corrected clock values in ns.
  **/
 static int stmmac_get_syncdevicetime(ktime_t *device,
 				     struct system_counterval_t *system,
 				     void *ctx)
 {
 	struct stmmac_priv *priv = (struct stmmac_priv *)ctx;

 	if (priv->plat->crosststamp)
 		return priv->plat->crosststamp(device, system, ctx);
 	else
 		return -EOPNOTSUPP;
 }

 static int stmmac_getcrosststamp(struct ptp_clock_info *ptp,
 				 struct system_device_crosststamp *xtstamp)
 {
 	struct stmmac_priv *priv =
 		container_of(ptp, struct stmmac_priv, ptp_clock_ops);

 	return get_device_system_crosststamp(stmmac_get_syncdevicetime,
 					     priv, NULL, xtstamp);
 }

 /* structure describing a PTP hardware clock */
 static struct ptp_clock_info stmmac_ptp_clock_ops = {
 	.owner = THIS_MODULE,
 	.name = "stmmac ptp",
 	.max_adj = 62500000,
 	.n_alarm = 0,
 	.n_ext_ts = 0, /* will be overwritten in stmmac_ptp_register */
 	.n_per_out = 0, /* will be overwritten in stmmac_ptp_register */
 	.n_pins = 0,
 	.pps = 0,
 	.adjfine = stmmac_adjust_freq,
 	.adjtime = stmmac_adjust_time,
 	.gettime64 = stmmac_get_time,
 	.settime64 = stmmac_set_time,
 	.enable = stmmac_enable,
 	.getcrosststamp = stmmac_getcrosststamp,
 };

 /**
  * stmmac_ptp_register
  * @priv: driver private structure
  * Description: this function will register the ptp clock driver
  * to kernel. It also does some house keeping work.
  */
 void stmmac_ptp_register(struct stmmac_priv *priv)
 {
 	int i;

 	for (i = 0; i < priv->dma_cap.pps_out_num; i++) {
 		if (i >= STMMAC_PPS_MAX)
 			break;
 		priv->pps[i].available = true;
 	}

 	if (priv->plat->ptp_max_adj)
 		stmmac_ptp_clock_ops.max_adj = priv->plat->ptp_max_adj;

 	/* Calculate the clock domain crossing (CDC) error if necessary */
 	priv->plat->cdc_error_adj = 0;
 	if (priv->plat->has_gmac4 && priv->plat->clk_ptp_rate)
 		priv->plat->cdc_error_adj = (2 * NSEC_PER_SEC) / priv->plat->clk_ptp_rate;

 	stmmac_ptp_clock_ops.n_per_out = priv->dma_cap.pps_out_num;
 	stmmac_ptp_clock_ops.n_ext_ts = priv->dma_cap.aux_snapshot_n;

 	rwlock_init(&priv->ptp_lock);
 	mutex_init(&priv->aux_ts_lock);
 	priv->ptp_clock_ops = stmmac_ptp_clock_ops;

 	priv->ptp_clock = ptp_clock_register(&priv->ptp_clock_ops,
 					     priv->device);
 	if (IS_ERR(priv->ptp_clock)) {
 		netdev_err(priv->dev, "ptp_clock_register failed\n");
 		priv->ptp_clock = NULL;
 	} else if (priv->ptp_clock)
 		netdev_info(priv->dev, "registered PTP clock\n");
 }

 /**
  * stmmac_ptp_unregister
  * @priv: driver private structure
  * Description: this function will remove/unregister the ptp clock driver
  * from the kernel.
  */
 void stmmac_ptp_unregister(struct stmmac_priv *priv)
 {
 	if (priv->ptp_clock) {
 		ptp_clock_unregister(priv->ptp_clock);
 		priv->ptp_clock = NULL;
 		pr_debug("Removed PTP HW clock successfully on %s\n",
 			 priv->dev->name);
 	}

 	mutex_destroy(&priv->aux_ts_lock);
 }
	// SPDX-License-Identifier: GPL-2.0-only
	/*******************************************************************************
	PTP 1588 clock using the STMMAC.

	Copyright (C) 2013 Vayavya Labs Pvt Ltd


	Author: Rayagond Kokatanur <rayagond@vayavyalabs.com>
	*******************************************************************************/
	#include "stmmac.h"
	#include "stmmac_ptp.h"
	#include "dwmac4.h"

	/**
	* stmmac_adjust_freq
	*
	* @ptp: pointer to ptp_clock_info structure
	* @scaled_ppm: desired period change in scaled parts per million
	*
	* Description: this function will adjust the frequency of hardware clock.
	*
	* Scaled parts per million is ppm with a 16-bit binary fractional field.
	*/
	static int stmmac_adjust_freq(struct ptp_clock_info *ptp, long scaled_ppm)
	{
	struct stmmac_priv *priv =
	container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	unsigned long flags;
	u32 addend;

	addend = adjust_by_scaled_ppm(priv->default_addend, scaled_ppm);

	write_lock_irqsave(&priv->ptp_lock, flags);
	stmmac_config_addend(priv, priv->ptpaddr, addend);
	write_unlock_irqrestore(&priv->ptp_lock, flags);

	return 0;
	}

	/**
	* stmmac_adjust_time
	*
	* @ptp: pointer to ptp_clock_info structure
	* @delta: desired change in nanoseconds
	*
	* Description: this function will shift/adjust the hardware clock time.
	*/
	static int stmmac_adjust_time(struct ptp_clock_info *ptp, s64 delta)
	{
	struct stmmac_priv *priv =
	container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	unsigned long flags;
	u32 sec, nsec;
	u32 quotient, reminder;
	int neg_adj = 0;
	bool xmac, est_rst = false;
	int ret;

	xmac = priv->plat->has_gmac4 \|\| priv->plat->has_xgmac;

	if (delta < 0) {
	neg_adj = 1;
	delta = -delta;
	}

	quotient = div_u64_rem(delta, 1000000000ULL, &reminder);
	sec = quotient;
	nsec = reminder;

	/* If EST is enabled, disabled it before adjust ptp time. */
	if (priv->est && priv->est->enable) {
	est_rst = true;
	mutex_lock(&priv->est_lock);
	priv->est->enable = false;
	stmmac_est_configure(priv, priv, priv->est,
	priv->plat->clk_ptp_rate);
	mutex_unlock(&priv->est_lock);
	}

	write_lock_irqsave(&priv->ptp_lock, flags);
	stmmac_adjust_systime(priv, priv->ptpaddr, sec, nsec, neg_adj, xmac);
	write_unlock_irqrestore(&priv->ptp_lock, flags);

	/* Calculate new basetime and re-configured EST after PTP time adjust. */
	if (est_rst) {
	struct timespec64 current_time, time;
	ktime_t current_time_ns, basetime;
	u64 cycle_time;

	mutex_lock(&priv->est_lock);
	priv->ptp_clock_ops.gettime64(&priv->ptp_clock_ops, &current_time);
	current_time_ns = timespec64_to_ktime(current_time);
	time.tv_nsec = priv->est->btr_reserve[0];
	time.tv_sec = priv->est->btr_reserve[1];
	basetime = timespec64_to_ktime(time);
	cycle_time = (u64)priv->est->ctr[1] * NSEC_PER_SEC +
	priv->est->ctr[0];
	time = stmmac_calc_tas_basetime(basetime,
	current_time_ns,
	cycle_time);

	priv->est->btr[0] = (u32)time.tv_nsec;
	priv->est->btr[1] = (u32)time.tv_sec;
	priv->est->enable = true;
	ret = stmmac_est_configure(priv, priv, priv->est,
	priv->plat->clk_ptp_rate);
	mutex_unlock(&priv->est_lock);
	if (ret)
	netdev_err(priv->dev, "failed to configure EST\n");
	}

	return 0;
	}

	/**
	* stmmac_get_time
	*
	* @ptp: pointer to ptp_clock_info structure
	* @ts: pointer to hold time/result
	*
	* Description: this function will read the current time from the
	* hardware clock and store it in @ts.
	*/
	static int stmmac_get_time(struct ptp_clock_info ptp, struct timespec64 ts)
	{
	struct stmmac_priv *priv =
	container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	unsigned long flags;
	u64 ns = 0;

	read_lock_irqsave(&priv->ptp_lock, flags);
	stmmac_get_systime(priv, priv->ptpaddr, &ns);
	read_unlock_irqrestore(&priv->ptp_lock, flags);

	*ts = ns_to_timespec64(ns);

	return 0;
	}

	/**
	* stmmac_set_time
	*
	* @ptp: pointer to ptp_clock_info structure
	* @ts: time value to set
	*
	* Description: this function will set the current time on the
	* hardware clock.
	*/
	static int stmmac_set_time(struct ptp_clock_info *ptp,
	const struct timespec64 *ts)
	{
	struct stmmac_priv *priv =
	container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	unsigned long flags;

	write_lock_irqsave(&priv->ptp_lock, flags);
	stmmac_init_systime(priv, priv->ptpaddr, ts->tv_sec, ts->tv_nsec);
	write_unlock_irqrestore(&priv->ptp_lock, flags);

	return 0;
	}

	static int stmmac_enable(struct ptp_clock_info *ptp,
	struct ptp_clock_request *rq, int on)
	{
	struct stmmac_priv *priv =
	container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	void __iomem *ptpaddr = priv->ptpaddr;
	struct stmmac_pps_cfg *cfg;
	int ret = -EOPNOTSUPP;
	unsigned long flags;
	u32 acr_value;

	switch (rq->type) {
	case PTP_CLK_REQ_PEROUT:
	/* Reject requests with unsupported flags */
	if (rq->perout.flags)
	return -EOPNOTSUPP;

	cfg = &priv->pps[rq->perout.index];

	cfg->start.tv_sec = rq->perout.start.sec;
	cfg->start.tv_nsec = rq->perout.start.nsec;
	cfg->period.tv_sec = rq->perout.period.sec;
	cfg->period.tv_nsec = rq->perout.period.nsec;

	write_lock_irqsave(&priv->ptp_lock, flags);
	ret = stmmac_flex_pps_config(priv, priv->ioaddr,
	rq->perout.index, cfg, on,
	priv->sub_second_inc,
	priv->systime_flags);
	write_unlock_irqrestore(&priv->ptp_lock, flags);
	break;
	case PTP_CLK_REQ_EXTTS: {
	u8 channel;

	mutex_lock(&priv->aux_ts_lock);
	acr_value = readl(ptpaddr + PTP_ACR);
	channel = ilog2(FIELD_GET(PTP_ACR_MASK, acr_value));
	acr_value &= ~PTP_ACR_MASK;

	if (on) {
	if (FIELD_GET(PTP_ACR_MASK, acr_value)) {
	netdev_err(priv->dev,
	"Cannot enable auxiliary snapshot %d as auxiliary snapshot %d is already enabled",
	rq->extts.index, channel);
	mutex_unlock(&priv->aux_ts_lock);
	return -EBUSY;
	}

	priv->plat->flags \|= STMMAC_FLAG_EXT_SNAPSHOT_EN;

	/* Enable External snapshot trigger */
	acr_value \|= PTP_ACR_ATSEN(rq->extts.index);
	acr_value \|= PTP_ACR_ATSFC;
	} else {
	priv->plat->flags &= ~STMMAC_FLAG_EXT_SNAPSHOT_EN;
	}
	netdev_dbg(priv->dev, "Auxiliary Snapshot %d %s.\n",
	rq->extts.index, on ? "enabled" : "disabled");
	writel(acr_value, ptpaddr + PTP_ACR);
	mutex_unlock(&priv->aux_ts_lock);
	/* wait for auxts fifo clear to finish */
	ret = readl_poll_timeout(ptpaddr + PTP_ACR, acr_value,
	!(acr_value & PTP_ACR_ATSFC),
	10, 10000);
	break;
	}

	default:
	break;
	}

	return ret;
	}

	/**
	* stmmac_get_syncdevicetime
	* @device: current device time
	* @system: system counter value read synchronously with device time
	* @ctx: context provided by timekeeping code
	* Description: Read device and system clock simultaneously and return the
	* corrected clock values in ns.
	**/
	static int stmmac_get_syncdevicetime(ktime_t *device,
	struct system_counterval_t *system,
	void *ctx)
	{
	struct stmmac_priv priv = (struct stmmac_priv )ctx;

	if (priv->plat->crosststamp)
	return priv->plat->crosststamp(device, system, ctx);
	else
	return -EOPNOTSUPP;
	}

	static int stmmac_getcrosststamp(struct ptp_clock_info *ptp,
	struct system_device_crosststamp *xtstamp)
	{
	struct stmmac_priv *priv =
	container_of(ptp, struct stmmac_priv, ptp_clock_ops);

	return get_device_system_crosststamp(stmmac_get_syncdevicetime,
	priv, NULL, xtstamp);
	}

	/* structure describing a PTP hardware clock */
	static struct ptp_clock_info stmmac_ptp_clock_ops = {
	.owner = THIS_MODULE,
	.name = "stmmac ptp",
	.max_adj = 62500000,
	.n_alarm = 0,
	.n_ext_ts = 0, /* will be overwritten in stmmac_ptp_register */
	.n_per_out = 0, /* will be overwritten in stmmac_ptp_register */
	.n_pins = 0,
	.pps = 0,
	.adjfine = stmmac_adjust_freq,
	.adjtime = stmmac_adjust_time,
	.gettime64 = stmmac_get_time,
	.settime64 = stmmac_set_time,
	.enable = stmmac_enable,
	.getcrosststamp = stmmac_getcrosststamp,
	};

	/**
	* stmmac_ptp_register
	* @priv: driver private structure
	* Description: this function will register the ptp clock driver
	* to kernel. It also does some house keeping work.
	*/
	void stmmac_ptp_register(struct stmmac_priv *priv)
	{
	int i;

	for (i = 0; i < priv->dma_cap.pps_out_num; i++) {
	if (i >= STMMAC_PPS_MAX)
	break;
	priv->pps[i].available = true;
	}

	if (priv->plat->ptp_max_adj)
	stmmac_ptp_clock_ops.max_adj = priv->plat->ptp_max_adj;

	/* Calculate the clock domain crossing (CDC) error if necessary */
	priv->plat->cdc_error_adj = 0;
	if (priv->plat->has_gmac4 && priv->plat->clk_ptp_rate)
	priv->plat->cdc_error_adj = (2 * NSEC_PER_SEC) / priv->plat->clk_ptp_rate;

	stmmac_ptp_clock_ops.n_per_out = priv->dma_cap.pps_out_num;
	stmmac_ptp_clock_ops.n_ext_ts = priv->dma_cap.aux_snapshot_n;

	rwlock_init(&priv->ptp_lock);
	mutex_init(&priv->aux_ts_lock);
	priv->ptp_clock_ops = stmmac_ptp_clock_ops;

	priv->ptp_clock = ptp_clock_register(&priv->ptp_clock_ops,
	priv->device);
	if (IS_ERR(priv->ptp_clock)) {
	netdev_err(priv->dev, "ptp_clock_register failed\n");
	priv->ptp_clock = NULL;
	} else if (priv->ptp_clock)
	netdev_info(priv->dev, "registered PTP clock\n");
	}

	/**
	* stmmac_ptp_unregister
	* @priv: driver private structure
	* Description: this function will remove/unregister the ptp clock driver
	* from the kernel.
	*/
	void stmmac_ptp_unregister(struct stmmac_priv *priv)
	{
	if (priv->ptp_clock) {
	ptp_clock_unregister(priv->ptp_clock);
	priv->ptp_clock = NULL;
	pr_debug("Removed PTP HW clock successfully on %s\n",
	priv->dev->name);
	}

	mutex_destroy(&priv->aux_ts_lock);
	}