diff options
Diffstat (limited to 'drivers/net/ethernet/freescale/fec_ptp.c')
| -rw-r--r-- | drivers/net/ethernet/freescale/fec_ptp.c | 383 |
1 files changed, 383 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 00000000000..c40526c78c2 --- /dev/null +++ b/drivers/net/ethernet/freescale/fec_ptp.c @@ -0,0 +1,383 @@ +/* + * 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. + */ + +#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/init.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_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_CC_MULT (1 << 31) +/** + * 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); + u32 tempval; + + tempval = readl(fep->hwp + FEC_ATIME_CTRL); + tempval |= FEC_T_CTRL_CAPTURE; + writel(tempval, fep->hwp + FEC_ATIME_CTRL); + + 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 / clk_get_rate(fep->clk_ptp); + + /* 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 free running count */ + writel(0, fep->hwp + FEC_ATIME_EVT_PERIOD); + + writel(FEC_T_CTRL_ENABLE, fep->hwp + FEC_ATIME_CTRL); + + memset(&fep->cc, 0, sizeof(fep->cc)); + fep->cc.read = fec_ptp_read; + fep->cc.mask = CLOCKSOURCE_MASK(32); + 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) +{ + u64 diff; + unsigned long flags; + int neg_adj = 0; + u32 mult = FEC_CC_MULT; + + struct fec_enet_private *fep = + container_of(ptp, struct fec_enet_private, ptp_caps); + + if (ppb < 0) { + ppb = -ppb; + neg_adj = 1; + } + + diff = mult; + diff *= ppb; + diff = div_u64(diff, 1000000000ULL); + + spin_lock_irqsave(&fep->tmreg_lock, flags); + /* + * dummy read to set cycle_last in tc to now. + * So use adjusted mult to calculate when next call + * timercounter_read. + */ + timecounter_read(&fep->tc); + + fep->cc.mult = neg_adj ? mult - diff : mult + diff; + + 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; + u64 now; + + spin_lock_irqsave(&fep->tmreg_lock, flags); + + now = timecounter_read(&fep->tc); + now += delta; + + /* reset the timecounter */ + timecounter_init(&fep->tc, &fep->cc, now); + + 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 timespec *ts) +{ + struct fec_enet_private *adapter = + container_of(ptp, struct fec_enet_private, ptp_caps); + u64 ns; + u32 remainder; + unsigned long flags; + + spin_lock_irqsave(&adapter->tmreg_lock, flags); + ns = timecounter_read(&adapter->tc); + spin_unlock_irqrestore(&adapter->tmreg_lock, flags); + + ts->tv_sec = div_u64_rem(ns, 1000000000ULL, &remainder); + ts->tv_nsec = remainder; + + 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 timespec *ts) +{ + struct fec_enet_private *fep = + container_of(ptp, struct fec_enet_private, ptp_caps); + + u64 ns; + unsigned long flags; + + ns = ts->tv_sec * 1000000000ULL; + ns += ts->tv_nsec; + + spin_lock_irqsave(&fep->tmreg_lock, flags); + timecounter_init(&fep->tc, &fep->cc, ns); + spin_unlock_irqrestore(&fep->tmreg_lock, flags); + 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) +{ + 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_ioctl(struct net_device *ndev, struct ifreq *ifr, int cmd) +{ + 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; +} + +/** + * 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(unsigned long _data) +{ + struct fec_enet_private *fep = (struct fec_enet_private *)_data; + u64 ns; + unsigned long flags; + + spin_lock_irqsave(&fep->tmreg_lock, flags); + ns = timecounter_read(&fep->tc); + spin_unlock_irqrestore(&fep->tmreg_lock, flags); + + mod_timer(&fep->time_keep, jiffies + 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 net_device *ndev, struct platform_device *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.pps = 0; + fep->ptp_caps.adjfreq = fec_ptp_adjfreq; + fep->ptp_caps.adjtime = fec_ptp_adjtime; + fep->ptp_caps.gettime = fec_ptp_gettime; + fep->ptp_caps.settime = fec_ptp_settime; + fep->ptp_caps.enable = fec_ptp_enable; + + spin_lock_init(&fep->tmreg_lock); + + fec_ptp_start_cyclecounter(ndev); + + init_timer(&fep->time_keep); + fep->time_keep.data = (unsigned long)fep; + fep->time_keep.function = fec_time_keep; + fep->time_keep.expires = jiffies + HZ; + add_timer(&fep->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"); + } else { + pr_info("registered PHC device on %s\n", ndev->name); + } +} |