diff options
Diffstat (limited to 'drivers/net/ethernet/freescale/fec_ptp.c')
| -rw-r--r-- | drivers/net/ethernet/freescale/fec_ptp.c | 639 |
1 files changed, 639 insertions, 0 deletions
diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c new file mode 100644 index 000000000..cffd9ad49 --- /dev/null +++ b/drivers/net/ethernet/freescale/fec_ptp.c @@ -0,0 +1,639 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Fast Ethernet Controller (ENET) PTP driver for MX6x. + * + * Copyright (C) 2012 Freescale Semiconductor, Inc. + */ + +#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; + struct timespec64 ts; + u64 ns; + + if (fep->pps_enable == enable) + return 0; + + fep->pps_channel = DEFAULT_PPS_CHANNEL; + fep->reload_period = PPS_OUPUT_RELOAD_PERIOD; + + 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 = fep->cc.read(&fep->cc); + /* Convert the ptp local counter to 1588 timestamp */ + ns = timecounter_cyc2time(&fep->tc, tempval); + ts = ns_to_timespec64(ns); + + /* 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 u64 fec_ptp_read(const struct cyclecounter *cc) +{ + struct fec_enet_private *fep = + container_of(cc, struct fec_enet_private, cc); + u32 tempval; + + tempval = readl(fep->hwp + FEC_ATIME_CTRL); + tempval |= FEC_T_CTRL_CAPTURE; + writel(tempval, fep->hwp + FEC_ATIME_CTRL); + + if (fep->quirks & 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, 0); + + 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); + corr_period = corr_period > 1 ? corr_period - 1 : corr_period; + 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; + + mutex_lock(&adapter->ptp_clk_mutex); + /* Check the ptp clock */ + if (!adapter->ptp_clk_on) { + mutex_unlock(&adapter->ptp_clk_mutex); + return -EINVAL; + } + spin_lock_irqsave(&adapter->tmreg_lock, flags); + ns = timecounter_read(&adapter->tc); + spin_unlock_irqrestore(&adapter->tmreg_lock, flags); + mutex_unlock(&adapter->ptp_clk_mutex); + + *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_disable_hwts - disable hardware time stamping + * @ndev: pointer to net_device + */ +void fec_ptp_disable_hwts(struct net_device *ndev) +{ + struct fec_enet_private *fep = netdev_priv(ndev); + + fep->hwts_tx_en = 0; + fep->hwts_rx_en = 0; +} + +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; + + 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: + fep->hwts_rx_en = 0; + break; + + default: + 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); + unsigned long flags; + + mutex_lock(&fep->ptp_clk_mutex); + if (fep->ptp_clk_on) { + spin_lock_irqsave(&fep->tmreg_lock, flags); + timecounter_read(&fep->tc); + spin_unlock_irqrestore(&fep->tmreg_lock, flags); + } + mutex_unlock(&fep->ptp_clk_mutex); + + schedule_delayed_work(&fep->time_keep, HZ); +} + +/* This function checks the pps event and reloads the timer compare counter. */ +static irqreturn_t fec_pps_interrupt(int irq, void *dev_id) +{ + struct net_device *ndev = dev_id; + struct fec_enet_private *fep = netdev_priv(ndev); + 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 IRQ_HANDLED; + } + + return IRQ_NONE; +} + +/** + * fec_ptp_init + * @pdev: The FEC network adapter + * @irq_idx: the interrupt index + * + * 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, int irq_idx) +{ + struct net_device *ndev = platform_get_drvdata(pdev); + struct fec_enet_private *fep = netdev_priv(ndev); + int irq; + int ret; + + fep->ptp_caps.owner = THIS_MODULE; + strscpy(fep->ptp_caps.name, "fec ptp", sizeof(fep->ptp_caps.name)); + + 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); + if (!fep->cycle_speed) { + fep->cycle_speed = NSEC_PER_SEC; + dev_err(&fep->pdev->dev, "clk_ptp clock rate is zero\n"); + } + 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); + + irq = platform_get_irq_byname_optional(pdev, "pps"); + if (irq < 0) + irq = platform_get_irq_optional(pdev, irq_idx); + /* Failure to get an irq is not fatal, + * only the PTP_CLOCK_PPS clock events should stop + */ + if (irq >= 0) { + ret = devm_request_irq(&pdev->dev, irq, fec_pps_interrupt, + 0, pdev->name, ndev); + if (ret < 0) + dev_warn(&pdev->dev, "request for pps irq failed(%d)\n", + ret); + } + + fep->ptp_clock = ptp_clock_register(&fep->ptp_caps, &pdev->dev); + if (IS_ERR(fep->ptp_clock)) { + fep->ptp_clock = NULL; + dev_err(&pdev->dev, "ptp_clock_register failed\n"); + } + + schedule_delayed_work(&fep->time_keep, HZ); +} + +void fec_ptp_stop(struct platform_device *pdev) +{ + struct net_device *ndev = platform_get_drvdata(pdev); + struct fec_enet_private *fep = netdev_priv(ndev); + + cancel_delayed_work_sync(&fep->time_keep); + if (fep->ptp_clock) + ptp_clock_unregister(fep->ptp_clock); +} |