--- /dev/null
+/*
+ * Fast Ethernet Controller (ENET) PTP driver for MX6x.
+ *
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/ptrace.h>
+#include <linux/errno.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/phy.h>
+#include <linux/fec.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/of_net.h>
+
+#include "fec.h"
+
+/* FEC 1588 register bits */
+#define FEC_T_CTRL_SLAVE 0x00002000
+#define FEC_T_CTRL_CAPTURE 0x00000800
+#define FEC_T_CTRL_RESTART 0x00000200
+#define FEC_T_CTRL_PERIOD_RST 0x00000030
+#define FEC_T_CTRL_PERIOD_EN 0x00000010
+#define FEC_T_CTRL_ENABLE 0x00000001
+
+#define FEC_T_INC_MASK 0x0000007f
+#define FEC_T_INC_OFFSET 0
+#define FEC_T_INC_CORR_MASK 0x00007f00
+#define FEC_T_INC_CORR_OFFSET 8
+
+#define FEC_T_CTRL_PINPER 0x00000080
+#define FEC_T_TF0_MASK 0x00000001
+#define FEC_T_TF0_OFFSET 0
+#define FEC_T_TF1_MASK 0x00000002
+#define FEC_T_TF1_OFFSET 1
+#define FEC_T_TF2_MASK 0x00000004
+#define FEC_T_TF2_OFFSET 2
+#define FEC_T_TF3_MASK 0x00000008
+#define FEC_T_TF3_OFFSET 3
+#define FEC_T_TDRE_MASK 0x00000001
+#define FEC_T_TDRE_OFFSET 0
+#define FEC_T_TMODE_MASK 0x0000003C
+#define FEC_T_TMODE_OFFSET 2
+#define FEC_T_TIE_MASK 0x00000040
+#define FEC_T_TIE_OFFSET 6
+#define FEC_T_TF_MASK 0x00000080
+#define FEC_T_TF_OFFSET 7
+
+#define FEC_ATIME_CTRL 0x400
+#define FEC_ATIME 0x404
+#define FEC_ATIME_EVT_OFFSET 0x408
+#define FEC_ATIME_EVT_PERIOD 0x40c
+#define FEC_ATIME_CORR 0x410
+#define FEC_ATIME_INC 0x414
+#define FEC_TS_TIMESTAMP 0x418
+
+#define FEC_TGSR 0x604
+#define FEC_TCSR(n) (0x608 + n * 0x08)
+#define FEC_TCCR(n) (0x60C + n * 0x08)
+#define MAX_TIMER_CHANNEL 3
+#define FEC_TMODE_TOGGLE 0x05
+#define FEC_HIGH_PULSE 0x0F
+
+#define FEC_CC_MULT (1 << 31)
+#define FEC_COUNTER_PERIOD (1 << 31)
+#define PPS_OUPUT_RELOAD_PERIOD NSEC_PER_SEC
+#define FEC_CHANNLE_0 0
+#define DEFAULT_PPS_CHANNEL FEC_CHANNLE_0
+
+/**
+ * fec_ptp_enable_pps
+ * @fep: the fec_enet_private structure handle
+ * @enable: enable the channel pps output
+ *
+ * This function enble the PPS ouput on the timer channel.
+ */
+static int fec_ptp_enable_pps(struct fec_enet_private *fep, uint enable)
+{
+ unsigned long flags;
+ u32 val, tempval;
+ int inc;
+ struct timespec ts;
+ u64 ns;
+ u32 remainder;
+ val = 0;
+
+ if (!(fep->hwts_tx_en || fep->hwts_rx_en)) {
+ dev_err(&fep->pdev->dev, "No ptp stack is running\n");
+ return -EINVAL;
+ }
+
+ if (fep->pps_enable == enable)
+ return 0;
+
+ fep->pps_channel = DEFAULT_PPS_CHANNEL;
+ fep->reload_period = PPS_OUPUT_RELOAD_PERIOD;
+ inc = fep->ptp_inc;
+
+ spin_lock_irqsave(&fep->tmreg_lock, flags);
+
+ if (enable) {
+ /* clear capture or output compare interrupt status if have.
+ */
+ writel(FEC_T_TF_MASK, fep->hwp + FEC_TCSR(fep->pps_channel));
+
+ /* It is recommended to double check the TMODE field in the
+ * TCSR register to be cleared before the first compare counter
+ * is written into TCCR register. Just add a double check.
+ */
+ val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
+ do {
+ val &= ~(FEC_T_TMODE_MASK);
+ writel(val, fep->hwp + FEC_TCSR(fep->pps_channel));
+ val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
+ } while (val & FEC_T_TMODE_MASK);
+
+ /* Dummy read counter to update the counter */
+ timecounter_read(&fep->tc);
+ /* We want to find the first compare event in the next
+ * second point. So we need to know what the ptp time
+ * is now and how many nanoseconds is ahead to get next second.
+ * The remaining nanosecond ahead before the next second would be
+ * NSEC_PER_SEC - ts.tv_nsec. Add the remaining nanoseconds
+ * to current timer would be next second.
+ */
+ tempval = readl(fep->hwp + FEC_ATIME_CTRL);
+ tempval |= FEC_T_CTRL_CAPTURE;
+ writel(tempval, fep->hwp + FEC_ATIME_CTRL);
+
+ tempval = readl(fep->hwp + FEC_ATIME);
+ /* Convert the ptp local counter to 1588 timestamp */
+ ns = timecounter_cyc2time(&fep->tc, tempval);
+ ts.tv_sec = div_u64_rem(ns, 1000000000ULL, &remainder);
+ ts.tv_nsec = remainder;
+
+ /* The tempval is less than 3 seconds, and so val is less than
+ * 4 seconds. No overflow for 32bit calculation.
+ */
+ val = NSEC_PER_SEC - (u32)ts.tv_nsec + tempval;
+
+ /* Need to consider the situation that the current time is
+ * very close to the second point, which means NSEC_PER_SEC
+ * - ts.tv_nsec is close to be zero(For example 20ns); Since the timer
+ * is still running when we calculate the first compare event, it is
+ * possible that the remaining nanoseonds run out before the compare
+ * counter is calculated and written into TCCR register. To avoid
+ * this possibility, we will set the compare event to be the next
+ * of next second. The current setting is 31-bit timer and wrap
+ * around over 2 seconds. So it is okay to set the next of next
+ * seond for the timer.
+ */
+ val += NSEC_PER_SEC;
+
+ /* We add (2 * NSEC_PER_SEC - (u32)ts.tv_nsec) to current
+ * ptp counter, which maybe cause 32-bit wrap. Since the
+ * (NSEC_PER_SEC - (u32)ts.tv_nsec) is less than 2 second.
+ * We can ensure the wrap will not cause issue. If the offset
+ * is bigger than fep->cc.mask would be a error.
+ */
+ val &= fep->cc.mask;
+ writel(val, fep->hwp + FEC_TCCR(fep->pps_channel));
+
+ /* Calculate the second the compare event timestamp */
+ fep->next_counter = (val + fep->reload_period) & fep->cc.mask;
+
+ /* * Enable compare event when overflow */
+ val = readl(fep->hwp + FEC_ATIME_CTRL);
+ val |= FEC_T_CTRL_PINPER;
+ writel(val, fep->hwp + FEC_ATIME_CTRL);
+
+ /* Compare channel setting. */
+ val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
+ val |= (1 << FEC_T_TF_OFFSET | 1 << FEC_T_TIE_OFFSET);
+ val &= ~(1 << FEC_T_TDRE_OFFSET);
+ val &= ~(FEC_T_TMODE_MASK);
+ val |= (FEC_HIGH_PULSE << FEC_T_TMODE_OFFSET);
+ writel(val, fep->hwp + FEC_TCSR(fep->pps_channel));
+
+ /* Write the second compare event timestamp and calculate
+ * the third timestamp. Refer the TCCR register detail in the spec.
+ */
+ writel(fep->next_counter, fep->hwp + FEC_TCCR(fep->pps_channel));
+ fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask;
+ } else {
+ writel(0, fep->hwp + FEC_TCSR(fep->pps_channel));
+ }
+
+ fep->pps_enable = enable;
+ spin_unlock_irqrestore(&fep->tmreg_lock, flags);
+
+ return 0;
+}
+
+/**
+ * fec_ptp_read - read raw cycle counter (to be used by time counter)
+ * @cc: the cyclecounter structure
+ *
+ * this function reads the cyclecounter registers and is called by the
+ * cyclecounter structure used to construct a ns counter from the
+ * arbitrary fixed point registers
+ */
+static cycle_t fec_ptp_read(const struct cyclecounter *cc)
+{
+ struct fec_enet_private *fep =
+ container_of(cc, struct fec_enet_private, cc);
+ const struct platform_device_id *id_entry =
+ platform_get_device_id(fep->pdev);
+ u32 tempval;
+
+ tempval = readl(fep->hwp + FEC_ATIME_CTRL);
+ tempval |= FEC_T_CTRL_CAPTURE;
+ writel(tempval, fep->hwp + FEC_ATIME_CTRL);
+
+ if (id_entry->driver_data & FEC_QUIRK_BUG_CAPTURE)
+ udelay(1);
+
+ return readl(fep->hwp + FEC_ATIME);
+}
+
+/**
+ * fec_ptp_start_cyclecounter - create the cycle counter from hw
+ * @ndev: network device
+ *
+ * this function initializes the timecounter and cyclecounter
+ * structures for use in generated a ns counter from the arbitrary
+ * fixed point cycles registers in the hardware.
+ */
+void fec_ptp_start_cyclecounter(struct net_device *ndev)
+{
+ struct fec_enet_private *fep = netdev_priv(ndev);
+ unsigned long flags;
+ int inc;
+
+ inc = 1000000000 / fep->cycle_speed;
+
+ /* grab the ptp lock */
+ spin_lock_irqsave(&fep->tmreg_lock, flags);
+
+ /* 1ns counter */
+ writel(inc << FEC_T_INC_OFFSET, fep->hwp + FEC_ATIME_INC);
+
+ /* use 31-bit timer counter */
+ writel(FEC_COUNTER_PERIOD, fep->hwp + FEC_ATIME_EVT_PERIOD);
+
+ writel(FEC_T_CTRL_ENABLE | FEC_T_CTRL_PERIOD_RST,
+ fep->hwp + FEC_ATIME_CTRL);
+
+ memset(&fep->cc, 0, sizeof(fep->cc));
+ fep->cc.read = fec_ptp_read;
+ fep->cc.mask = CLOCKSOURCE_MASK(31);
+ fep->cc.shift = 31;
+ fep->cc.mult = FEC_CC_MULT;
+
+ /* reset the ns time counter */
+ timecounter_init(&fep->tc, &fep->cc, ktime_to_ns(ktime_get_real()));
+
+ spin_unlock_irqrestore(&fep->tmreg_lock, flags);
+}
+
+/**
+ * fec_ptp_adjfreq - adjust ptp cycle frequency
+ * @ptp: the ptp clock structure
+ * @ppb: parts per billion adjustment from base
+ *
+ * Adjust the frequency of the ptp cycle counter by the
+ * indicated ppb from the base frequency.
+ *
+ * Because ENET hardware frequency adjust is complex,
+ * using software method to do that.
+ */
+static int fec_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
+{
+ unsigned long flags;
+ int neg_adj = 0;
+ u32 i, tmp;
+ u32 corr_inc, corr_period;
+ u32 corr_ns;
+ u64 lhs, rhs;
+
+ struct fec_enet_private *fep =
+ container_of(ptp, struct fec_enet_private, ptp_caps);
+
+ if (ppb == 0)
+ return 0;
+
+ if (ppb < 0) {
+ ppb = -ppb;
+ neg_adj = 1;
+ }
+
+ /* In theory, corr_inc/corr_period = ppb/NSEC_PER_SEC;
+ * Try to find the corr_inc between 1 to fep->ptp_inc to
+ * meet adjustment requirement.
+ */
+ lhs = NSEC_PER_SEC;
+ rhs = (u64)ppb * (u64)fep->ptp_inc;
+ for (i = 1; i <= fep->ptp_inc; i++) {
+ if (lhs >= rhs) {
+ corr_inc = i;
+ corr_period = div_u64(lhs, rhs);
+ break;
+ }
+ lhs += NSEC_PER_SEC;
+ }
+ /* Not found? Set it to high value - double speed
+ * correct in every clock step.
+ */
+ if (i > fep->ptp_inc) {
+ corr_inc = fep->ptp_inc;
+ corr_period = 1;
+ }
+
+ if (neg_adj)
+ corr_ns = fep->ptp_inc - corr_inc;
+ else
+ corr_ns = fep->ptp_inc + corr_inc;
+
+ spin_lock_irqsave(&fep->tmreg_lock, flags);
+
+ tmp = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_MASK;
+ tmp |= corr_ns << FEC_T_INC_CORR_OFFSET;
+ writel(tmp, fep->hwp + FEC_ATIME_INC);
+ writel(corr_period, fep->hwp + FEC_ATIME_CORR);
+ /* dummy read to update the timer. */
+ timecounter_read(&fep->tc);
+
+ spin_unlock_irqrestore(&fep->tmreg_lock, flags);
+
+ return 0;
+}
+
+/**
+ * fec_ptp_adjtime
+ * @ptp: the ptp clock structure
+ * @delta: offset to adjust the cycle counter by
+ *
+ * adjust the timer by resetting the timecounter structure.
+ */
+static int fec_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+ struct fec_enet_private *fep =
+ container_of(ptp, struct fec_enet_private, ptp_caps);
+ unsigned long flags;
+
+ spin_lock_irqsave(&fep->tmreg_lock, flags);
+ timecounter_adjtime(&fep->tc, delta);
+ spin_unlock_irqrestore(&fep->tmreg_lock, flags);
+
+ return 0;
+}
+
+/**
+ * fec_ptp_gettime
+ * @ptp: the ptp clock structure
+ * @ts: timespec structure to hold the current time value
+ *
+ * read the timecounter and return the correct value on ns,
+ * after converting it into a struct timespec.
+ */
+static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
+{
+ struct fec_enet_private *adapter =
+ container_of(ptp, struct fec_enet_private, ptp_caps);
+ u64 ns;
+ unsigned long flags;
+
+ spin_lock_irqsave(&adapter->tmreg_lock, flags);
+ ns = timecounter_read(&adapter->tc);
+ spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
+
+ *ts = ns_to_timespec64(ns);
+
+ return 0;
+}
+
+/**
+ * fec_ptp_settime
+ * @ptp: the ptp clock structure
+ * @ts: the 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 fec_ptp_settime(struct ptp_clock_info *ptp,
+ const struct timespec64 *ts)
+{
+ struct fec_enet_private *fep =
+ container_of(ptp, struct fec_enet_private, ptp_caps);
+
+ u64 ns;
+ unsigned long flags;
+ u32 counter;
+
+ mutex_lock(&fep->ptp_clk_mutex);
+ /* Check the ptp clock */
+ if (!fep->ptp_clk_on) {
+ mutex_unlock(&fep->ptp_clk_mutex);
+ return -EINVAL;
+ }
+
+ ns = timespec64_to_ns(ts);
+ /* Get the timer value based on timestamp.
+ * Update the counter with the masked value.
+ */
+ counter = ns & fep->cc.mask;
+
+ spin_lock_irqsave(&fep->tmreg_lock, flags);
+ writel(counter, fep->hwp + FEC_ATIME);
+ timecounter_init(&fep->tc, &fep->cc, ns);
+ spin_unlock_irqrestore(&fep->tmreg_lock, flags);
+ mutex_unlock(&fep->ptp_clk_mutex);
+ return 0;
+}
+
+/**
+ * fec_ptp_enable
+ * @ptp: the ptp clock structure
+ * @rq: the requested feature to change
+ * @on: whether to enable or disable the feature
+ *
+ */
+static int fec_ptp_enable(struct ptp_clock_info *ptp,
+ struct ptp_clock_request *rq, int on)
+{
+ struct fec_enet_private *fep =
+ container_of(ptp, struct fec_enet_private, ptp_caps);
+ int ret = 0;
+
+ if (rq->type == PTP_CLK_REQ_PPS) {
+ ret = fec_ptp_enable_pps(fep, on);
+
+ return ret;
+ }
+ return -EOPNOTSUPP;
+}
+
+/**
+ * fec_ptp_hwtstamp_ioctl - control hardware time stamping
+ * @ndev: pointer to net_device
+ * @ifreq: ioctl data
+ * @cmd: particular ioctl requested
+ */
+int fec_ptp_set(struct net_device *ndev, struct ifreq *ifr)
+{
+ struct fec_enet_private *fep = netdev_priv(ndev);
+
+ struct hwtstamp_config config;
+
+ if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
+ return -EFAULT;
+
+ /* reserved for future extensions */
+ if (config.flags)
+ return -EINVAL;
+
+ switch (config.tx_type) {
+ case HWTSTAMP_TX_OFF:
+ fep->hwts_tx_en = 0;
+ break;
+ case HWTSTAMP_TX_ON:
+ fep->hwts_tx_en = 1;
+ break;
+ default:
+ return -ERANGE;
+ }
+
+ switch (config.rx_filter) {
+ case HWTSTAMP_FILTER_NONE:
+ if (fep->hwts_rx_en)
+ fep->hwts_rx_en = 0;
+ config.rx_filter = HWTSTAMP_FILTER_NONE;
+ break;
+
+ default:
+ /*
+ * register RXMTRL must be set in order to do V1 packets,
+ * therefore it is not possible to time stamp both V1 Sync and
+ * Delay_Req messages and hardware does not support
+ * timestamping all packets => return error
+ */
+ fep->hwts_rx_en = 1;
+ config.rx_filter = HWTSTAMP_FILTER_ALL;
+ break;
+ }
+
+ return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
+ -EFAULT : 0;
+}
+
+int fec_ptp_get(struct net_device *ndev, struct ifreq *ifr)
+{
+ struct fec_enet_private *fep = netdev_priv(ndev);
+ struct hwtstamp_config config;
+
+ config.flags = 0;
+ config.tx_type = fep->hwts_tx_en ? HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
+ config.rx_filter = (fep->hwts_rx_en ?
+ HWTSTAMP_FILTER_ALL : HWTSTAMP_FILTER_NONE);
+
+ return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
+ -EFAULT : 0;
+}
+
+/**
+ * fec_time_keep - call timecounter_read every second to avoid timer overrun
+ * because ENET just support 32bit counter, will timeout in 4s
+ */
+static void fec_time_keep(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct fec_enet_private *fep = container_of(dwork, struct fec_enet_private, time_keep);
+ u64 ns;
+ unsigned long flags;
+
+ mutex_lock(&fep->ptp_clk_mutex);
+ if (fep->ptp_clk_on) {
+ spin_lock_irqsave(&fep->tmreg_lock, flags);
+ ns = timecounter_read(&fep->tc);
+ spin_unlock_irqrestore(&fep->tmreg_lock, flags);
+ }
+ mutex_unlock(&fep->ptp_clk_mutex);
+
+ schedule_delayed_work(&fep->time_keep, HZ);
+}
+
+/**
+ * fec_ptp_init
+ * @ndev: The FEC network adapter
+ *
+ * This function performs the required steps for enabling ptp
+ * support. If ptp support has already been loaded it simply calls the
+ * cyclecounter init routine and exits.
+ */
+
+void fec_ptp_init(struct platform_device *pdev)
+{
+ struct net_device *ndev = platform_get_drvdata(pdev);
+ struct fec_enet_private *fep = netdev_priv(ndev);
+
+ fep->ptp_caps.owner = THIS_MODULE;
+ snprintf(fep->ptp_caps.name, 16, "fec ptp");
+
+ fep->ptp_caps.max_adj = 250000000;
+ fep->ptp_caps.n_alarm = 0;
+ fep->ptp_caps.n_ext_ts = 0;
+ fep->ptp_caps.n_per_out = 0;
+ fep->ptp_caps.n_pins = 0;
+ fep->ptp_caps.pps = 1;
+ fep->ptp_caps.adjfreq = fec_ptp_adjfreq;
+ fep->ptp_caps.adjtime = fec_ptp_adjtime;
+ fep->ptp_caps.gettime64 = fec_ptp_gettime;
+ fep->ptp_caps.settime64 = fec_ptp_settime;
+ fep->ptp_caps.enable = fec_ptp_enable;
+
+ fep->cycle_speed = clk_get_rate(fep->clk_ptp);
+ fep->ptp_inc = NSEC_PER_SEC / fep->cycle_speed;
+
+ spin_lock_init(&fep->tmreg_lock);
+
+ fec_ptp_start_cyclecounter(ndev);
+
+ INIT_DELAYED_WORK(&fep->time_keep, fec_time_keep);
+
+ fep->ptp_clock = ptp_clock_register(&fep->ptp_caps, &pdev->dev);
+ if (IS_ERR(fep->ptp_clock)) {
+ fep->ptp_clock = NULL;
+ pr_err("ptp_clock_register failed\n");
+ }
+
+ schedule_delayed_work(&fep->time_keep, HZ);
+}
+
+/**
+ * fec_ptp_check_pps_event
+ * @fep: the fec_enet_private structure handle
+ *
+ * This function check the pps event and reload the timer compare counter.
+ */
+uint fec_ptp_check_pps_event(struct fec_enet_private *fep)
+{
+ u32 val;
+ u8 channel = fep->pps_channel;
+ struct ptp_clock_event event;
+
+ val = readl(fep->hwp + FEC_TCSR(channel));
+ if (val & FEC_T_TF_MASK) {
+ /* Write the next next compare(not the next according the spec)
+ * value to the register
+ */
+ writel(fep->next_counter, fep->hwp + FEC_TCCR(channel));
+ do {
+ writel(val, fep->hwp + FEC_TCSR(channel));
+ } while (readl(fep->hwp + FEC_TCSR(channel)) & FEC_T_TF_MASK);
+
+ /* Update the counter; */
+ fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask;
+
+ event.type = PTP_CLOCK_PPS;
+ ptp_clock_event(fep->ptp_clock, &event);
+ return 1;
+ }
+
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff