ptp: Added a clock that uses the eTSEC found on the MPC85xx.
The eTSEC includes a PTP clock with quite a few features. This patch adds
support for the basic clock adjustment functions, plus two external time
stamps, one alarm, and the PPS callback.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
diff --git a/drivers/net/gianfar_ptp.c b/drivers/net/gianfar_ptp.c
new file mode 100644
index 0000000..d8e1753
--- /dev/null
+++ b/drivers/net/gianfar_ptp.c
@@ -0,0 +1,588 @@
+/*
+ * PTP 1588 clock using the eTSEC
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/device.h>
+#include <linux/hrtimer.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/timex.h>
+#include <linux/io.h>
+
+#include <linux/ptp_clock_kernel.h>
+
+#include "gianfar.h"
+
+/*
+ * gianfar ptp registers
+ * Generated by regen.tcl on Thu May 13 01:38:57 PM CEST 2010
+ */
+struct gianfar_ptp_registers {
+ u32 tmr_ctrl; /* Timer control register */
+ u32 tmr_tevent; /* Timestamp event register */
+ u32 tmr_temask; /* Timer event mask register */
+ u32 tmr_pevent; /* Timestamp event register */
+ u32 tmr_pemask; /* Timer event mask register */
+ u32 tmr_stat; /* Timestamp status register */
+ u32 tmr_cnt_h; /* Timer counter high register */
+ u32 tmr_cnt_l; /* Timer counter low register */
+ u32 tmr_add; /* Timer drift compensation addend register */
+ u32 tmr_acc; /* Timer accumulator register */
+ u32 tmr_prsc; /* Timer prescale */
+ u8 res1[4];
+ u32 tmroff_h; /* Timer offset high */
+ u32 tmroff_l; /* Timer offset low */
+ u8 res2[8];
+ u32 tmr_alarm1_h; /* Timer alarm 1 high register */
+ u32 tmr_alarm1_l; /* Timer alarm 1 high register */
+ u32 tmr_alarm2_h; /* Timer alarm 2 high register */
+ u32 tmr_alarm2_l; /* Timer alarm 2 high register */
+ u8 res3[48];
+ u32 tmr_fiper1; /* Timer fixed period interval */
+ u32 tmr_fiper2; /* Timer fixed period interval */
+ u32 tmr_fiper3; /* Timer fixed period interval */
+ u8 res4[20];
+ u32 tmr_etts1_h; /* Timestamp of general purpose external trigger */
+ u32 tmr_etts1_l; /* Timestamp of general purpose external trigger */
+ u32 tmr_etts2_h; /* Timestamp of general purpose external trigger */
+ u32 tmr_etts2_l; /* Timestamp of general purpose external trigger */
+};
+
+/* Bit definitions for the TMR_CTRL register */
+#define ALM1P (1<<31) /* Alarm1 output polarity */
+#define ALM2P (1<<30) /* Alarm2 output polarity */
+#define FS (1<<28) /* FIPER start indication */
+#define PP1L (1<<27) /* Fiper1 pulse loopback mode enabled. */
+#define PP2L (1<<26) /* Fiper2 pulse loopback mode enabled. */
+#define TCLK_PERIOD_SHIFT (16) /* 1588 timer reference clock period. */
+#define TCLK_PERIOD_MASK (0x3ff)
+#define RTPE (1<<15) /* Record Tx Timestamp to PAL Enable. */
+#define FRD (1<<14) /* FIPER Realignment Disable */
+#define ESFDP (1<<11) /* External Tx/Rx SFD Polarity. */
+#define ESFDE (1<<10) /* External Tx/Rx SFD Enable. */
+#define ETEP2 (1<<9) /* External trigger 2 edge polarity */
+#define ETEP1 (1<<8) /* External trigger 1 edge polarity */
+#define COPH (1<<7) /* Generated clock output phase. */
+#define CIPH (1<<6) /* External oscillator input clock phase */
+#define TMSR (1<<5) /* Timer soft reset. */
+#define BYP (1<<3) /* Bypass drift compensated clock */
+#define TE (1<<2) /* 1588 timer enable. */
+#define CKSEL_SHIFT (0) /* 1588 Timer reference clock source */
+#define CKSEL_MASK (0x3)
+
+/* Bit definitions for the TMR_TEVENT register */
+#define ETS2 (1<<25) /* External trigger 2 timestamp sampled */
+#define ETS1 (1<<24) /* External trigger 1 timestamp sampled */
+#define ALM2 (1<<17) /* Current time = alarm time register 2 */
+#define ALM1 (1<<16) /* Current time = alarm time register 1 */
+#define PP1 (1<<7) /* periodic pulse generated on FIPER1 */
+#define PP2 (1<<6) /* periodic pulse generated on FIPER2 */
+#define PP3 (1<<5) /* periodic pulse generated on FIPER3 */
+
+/* Bit definitions for the TMR_TEMASK register */
+#define ETS2EN (1<<25) /* External trigger 2 timestamp enable */
+#define ETS1EN (1<<24) /* External trigger 1 timestamp enable */
+#define ALM2EN (1<<17) /* Timer ALM2 event enable */
+#define ALM1EN (1<<16) /* Timer ALM1 event enable */
+#define PP1EN (1<<7) /* Periodic pulse event 1 enable */
+#define PP2EN (1<<6) /* Periodic pulse event 2 enable */
+
+/* Bit definitions for the TMR_PEVENT register */
+#define TXP2 (1<<9) /* PTP transmitted timestamp im TXTS2 */
+#define TXP1 (1<<8) /* PTP transmitted timestamp in TXTS1 */
+#define RXP (1<<0) /* PTP frame has been received */
+
+/* Bit definitions for the TMR_PEMASK register */
+#define TXP2EN (1<<9) /* Transmit PTP packet event 2 enable */
+#define TXP1EN (1<<8) /* Transmit PTP packet event 1 enable */
+#define RXPEN (1<<0) /* Receive PTP packet event enable */
+
+/* Bit definitions for the TMR_STAT register */
+#define STAT_VEC_SHIFT (0) /* Timer general purpose status vector */
+#define STAT_VEC_MASK (0x3f)
+
+/* Bit definitions for the TMR_PRSC register */
+#define PRSC_OCK_SHIFT (0) /* Output clock division/prescale factor. */
+#define PRSC_OCK_MASK (0xffff)
+
+
+#define DRIVER "gianfar_ptp"
+#define DEFAULT_CKSEL 1
+#define N_ALARM 1 /* first alarm is used internally to reset fipers */
+#define N_EXT_TS 2
+#define REG_SIZE sizeof(struct gianfar_ptp_registers)
+
+struct etsects {
+ struct gianfar_ptp_registers *regs;
+ spinlock_t lock; /* protects regs */
+ struct ptp_clock *clock;
+ struct ptp_clock_info caps;
+ struct resource *rsrc;
+ int irq;
+ u64 alarm_interval; /* for periodic alarm */
+ u64 alarm_value;
+ u32 tclk_period; /* nanoseconds */
+ u32 tmr_prsc;
+ u32 tmr_add;
+ u32 cksel;
+ u32 tmr_fiper1;
+ u32 tmr_fiper2;
+};
+
+/*
+ * Register access functions
+ */
+
+/* Caller must hold etsects->lock. */
+static u64 tmr_cnt_read(struct etsects *etsects)
+{
+ u64 ns;
+ u32 lo, hi;
+
+ lo = gfar_read(&etsects->regs->tmr_cnt_l);
+ hi = gfar_read(&etsects->regs->tmr_cnt_h);
+ ns = ((u64) hi) << 32;
+ ns |= lo;
+ return ns;
+}
+
+/* Caller must hold etsects->lock. */
+static void tmr_cnt_write(struct etsects *etsects, u64 ns)
+{
+ u32 hi = ns >> 32;
+ u32 lo = ns & 0xffffffff;
+
+ gfar_write(&etsects->regs->tmr_cnt_l, lo);
+ gfar_write(&etsects->regs->tmr_cnt_h, hi);
+}
+
+/* Caller must hold etsects->lock. */
+static void set_alarm(struct etsects *etsects)
+{
+ u64 ns;
+ u32 lo, hi;
+
+ ns = tmr_cnt_read(etsects) + 1500000000ULL;
+ ns = div_u64(ns, 1000000000UL) * 1000000000ULL;
+ ns -= etsects->tclk_period;
+ hi = ns >> 32;
+ lo = ns & 0xffffffff;
+ gfar_write(&etsects->regs->tmr_alarm1_l, lo);
+ gfar_write(&etsects->regs->tmr_alarm1_h, hi);
+}
+
+/* Caller must hold etsects->lock. */
+static void set_fipers(struct etsects *etsects)
+{
+ u32 tmr_ctrl = gfar_read(&etsects->regs->tmr_ctrl);
+
+ gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl & (~TE));
+ gfar_write(&etsects->regs->tmr_prsc, etsects->tmr_prsc);
+ gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
+ gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
+ set_alarm(etsects);
+ gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl|TE);
+}
+
+/*
+ * Interrupt service routine
+ */
+
+static irqreturn_t isr(int irq, void *priv)
+{
+ struct etsects *etsects = priv;
+ struct ptp_clock_event event;
+ u64 ns;
+ u32 ack = 0, lo, hi, mask, val;
+
+ val = gfar_read(&etsects->regs->tmr_tevent);
+
+ if (val & ETS1) {
+ ack |= ETS1;
+ hi = gfar_read(&etsects->regs->tmr_etts1_h);
+ lo = gfar_read(&etsects->regs->tmr_etts1_l);
+ event.type = PTP_CLOCK_EXTTS;
+ event.index = 0;
+ event.timestamp = ((u64) hi) << 32;
+ event.timestamp |= lo;
+ ptp_clock_event(etsects->clock, &event);
+ }
+
+ if (val & ETS2) {
+ ack |= ETS2;
+ hi = gfar_read(&etsects->regs->tmr_etts2_h);
+ lo = gfar_read(&etsects->regs->tmr_etts2_l);
+ event.type = PTP_CLOCK_EXTTS;
+ event.index = 1;
+ event.timestamp = ((u64) hi) << 32;
+ event.timestamp |= lo;
+ ptp_clock_event(etsects->clock, &event);
+ }
+
+ if (val & ALM2) {
+ ack |= ALM2;
+ if (etsects->alarm_value) {
+ event.type = PTP_CLOCK_ALARM;
+ event.index = 0;
+ event.timestamp = etsects->alarm_value;
+ ptp_clock_event(etsects->clock, &event);
+ }
+ if (etsects->alarm_interval) {
+ ns = etsects->alarm_value + etsects->alarm_interval;
+ hi = ns >> 32;
+ lo = ns & 0xffffffff;
+ spin_lock(&etsects->lock);
+ gfar_write(&etsects->regs->tmr_alarm2_l, lo);
+ gfar_write(&etsects->regs->tmr_alarm2_h, hi);
+ spin_unlock(&etsects->lock);
+ etsects->alarm_value = ns;
+ } else {
+ gfar_write(&etsects->regs->tmr_tevent, ALM2);
+ spin_lock(&etsects->lock);
+ mask = gfar_read(&etsects->regs->tmr_temask);
+ mask &= ~ALM2EN;
+ gfar_write(&etsects->regs->tmr_temask, mask);
+ spin_unlock(&etsects->lock);
+ etsects->alarm_value = 0;
+ etsects->alarm_interval = 0;
+ }
+ }
+
+ if (val & PP1) {
+ ack |= PP1;
+ event.type = PTP_CLOCK_PPS;
+ ptp_clock_event(etsects->clock, &event);
+ }
+
+ if (ack) {
+ gfar_write(&etsects->regs->tmr_tevent, ack);
+ return IRQ_HANDLED;
+ } else
+ return IRQ_NONE;
+}
+
+/*
+ * PTP clock operations
+ */
+
+static int ptp_gianfar_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
+{
+ u64 adj;
+ u32 diff, tmr_add;
+ int neg_adj = 0;
+ struct etsects *etsects = container_of(ptp, struct etsects, caps);
+
+ if (ppb < 0) {
+ neg_adj = 1;
+ ppb = -ppb;
+ }
+ tmr_add = etsects->tmr_add;
+ adj = tmr_add;
+ adj *= ppb;
+ diff = div_u64(adj, 1000000000ULL);
+
+ tmr_add = neg_adj ? tmr_add - diff : tmr_add + diff;
+
+ gfar_write(&etsects->regs->tmr_add, tmr_add);
+
+ return 0;
+}
+
+static int ptp_gianfar_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+ s64 now;
+ unsigned long flags;
+ struct etsects *etsects = container_of(ptp, struct etsects, caps);
+
+ spin_lock_irqsave(&etsects->lock, flags);
+
+ now = tmr_cnt_read(etsects);
+ now += delta;
+ tmr_cnt_write(etsects, now);
+
+ spin_unlock_irqrestore(&etsects->lock, flags);
+
+ set_fipers(etsects);
+
+ return 0;
+}
+
+static int ptp_gianfar_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
+{
+ u64 ns;
+ u32 remainder;
+ unsigned long flags;
+ struct etsects *etsects = container_of(ptp, struct etsects, caps);
+
+ spin_lock_irqsave(&etsects->lock, flags);
+
+ ns = tmr_cnt_read(etsects);
+
+ spin_unlock_irqrestore(&etsects->lock, flags);
+
+ ts->tv_sec = div_u64_rem(ns, 1000000000, &remainder);
+ ts->tv_nsec = remainder;
+ return 0;
+}
+
+static int ptp_gianfar_settime(struct ptp_clock_info *ptp,
+ const struct timespec *ts)
+{
+ u64 ns;
+ unsigned long flags;
+ struct etsects *etsects = container_of(ptp, struct etsects, caps);
+
+ ns = ts->tv_sec * 1000000000ULL;
+ ns += ts->tv_nsec;
+
+ spin_lock_irqsave(&etsects->lock, flags);
+
+ tmr_cnt_write(etsects, ns);
+ set_fipers(etsects);
+
+ spin_unlock_irqrestore(&etsects->lock, flags);
+
+ return 0;
+}
+
+static int ptp_gianfar_enable(struct ptp_clock_info *ptp,
+ struct ptp_clock_request *rq, int on)
+{
+ struct etsects *etsects = container_of(ptp, struct etsects, caps);
+ unsigned long flags;
+ u32 bit, mask;
+
+ switch (rq->type) {
+ case PTP_CLK_REQ_EXTTS:
+ switch (rq->extts.index) {
+ case 0:
+ bit = ETS1EN;
+ break;
+ case 1:
+ bit = ETS2EN;
+ break;
+ default:
+ return -EINVAL;
+ }
+ spin_lock_irqsave(&etsects->lock, flags);
+ mask = gfar_read(&etsects->regs->tmr_temask);
+ if (on)
+ mask |= bit;
+ else
+ mask &= ~bit;
+ gfar_write(&etsects->regs->tmr_temask, mask);
+ spin_unlock_irqrestore(&etsects->lock, flags);
+ return 0;
+
+ case PTP_CLK_REQ_PPS:
+ spin_lock_irqsave(&etsects->lock, flags);
+ mask = gfar_read(&etsects->regs->tmr_temask);
+ if (on)
+ mask |= PP1EN;
+ else
+ mask &= ~PP1EN;
+ gfar_write(&etsects->regs->tmr_temask, mask);
+ spin_unlock_irqrestore(&etsects->lock, flags);
+ return 0;
+
+ default:
+ break;
+ }
+
+ return -EOPNOTSUPP;
+}
+
+static struct ptp_clock_info ptp_gianfar_caps = {
+ .owner = THIS_MODULE,
+ .name = "gianfar clock",
+ .max_adj = 512000,
+ .n_alarm = N_ALARM,
+ .n_ext_ts = N_EXT_TS,
+ .n_per_out = 0,
+ .pps = 1,
+ .adjfreq = ptp_gianfar_adjfreq,
+ .adjtime = ptp_gianfar_adjtime,
+ .gettime = ptp_gianfar_gettime,
+ .settime = ptp_gianfar_settime,
+ .enable = ptp_gianfar_enable,
+};
+
+/* OF device tree */
+
+static int get_of_u32(struct device_node *node, char *str, u32 *val)
+{
+ int plen;
+ const u32 *prop = of_get_property(node, str, &plen);
+
+ if (!prop || plen != sizeof(*prop))
+ return -1;
+ *val = *prop;
+ return 0;
+}
+
+static int gianfar_ptp_probe(struct platform_device *dev)
+{
+ struct device_node *node = dev->dev.of_node;
+ struct etsects *etsects;
+ struct timespec now;
+ int err = -ENOMEM;
+ u32 tmr_ctrl;
+ unsigned long flags;
+
+ etsects = kzalloc(sizeof(*etsects), GFP_KERNEL);
+ if (!etsects)
+ goto no_memory;
+
+ err = -ENODEV;
+
+ etsects->caps = ptp_gianfar_caps;
+ etsects->cksel = DEFAULT_CKSEL;
+
+ if (get_of_u32(node, "fsl,tclk-period", &etsects->tclk_period) ||
+ get_of_u32(node, "fsl,tmr-prsc", &etsects->tmr_prsc) ||
+ get_of_u32(node, "fsl,tmr-add", &etsects->tmr_add) ||
+ get_of_u32(node, "fsl,tmr-fiper1", &etsects->tmr_fiper1) ||
+ get_of_u32(node, "fsl,tmr-fiper2", &etsects->tmr_fiper2) ||
+ get_of_u32(node, "fsl,max-adj", &etsects->caps.max_adj)) {
+ pr_err("device tree node missing required elements\n");
+ goto no_node;
+ }
+
+ etsects->irq = platform_get_irq(dev, 0);
+
+ if (etsects->irq == NO_IRQ) {
+ pr_err("irq not in device tree\n");
+ goto no_node;
+ }
+ if (request_irq(etsects->irq, isr, 0, DRIVER, etsects)) {
+ pr_err("request_irq failed\n");
+ goto no_node;
+ }
+
+ etsects->rsrc = platform_get_resource(dev, IORESOURCE_MEM, 0);
+ if (!etsects->rsrc) {
+ pr_err("no resource\n");
+ goto no_resource;
+ }
+ if (request_resource(&ioport_resource, etsects->rsrc)) {
+ pr_err("resource busy\n");
+ goto no_resource;
+ }
+
+ spin_lock_init(&etsects->lock);
+
+ etsects->regs = ioremap(etsects->rsrc->start,
+ 1 + etsects->rsrc->end - etsects->rsrc->start);
+ if (!etsects->regs) {
+ pr_err("ioremap ptp registers failed\n");
+ goto no_ioremap;
+ }
+ getnstimeofday(&now);
+ ptp_gianfar_settime(&etsects->caps, &now);
+
+ tmr_ctrl =
+ (etsects->tclk_period & TCLK_PERIOD_MASK) << TCLK_PERIOD_SHIFT |
+ (etsects->cksel & CKSEL_MASK) << CKSEL_SHIFT;
+
+ spin_lock_irqsave(&etsects->lock, flags);
+
+ gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl);
+ gfar_write(&etsects->regs->tmr_add, etsects->tmr_add);
+ gfar_write(&etsects->regs->tmr_prsc, etsects->tmr_prsc);
+ gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
+ gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
+ set_alarm(etsects);
+ gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl|FS|RTPE|TE);
+
+ spin_unlock_irqrestore(&etsects->lock, flags);
+
+ etsects->clock = ptp_clock_register(&etsects->caps);
+ if (IS_ERR(etsects->clock)) {
+ err = PTR_ERR(etsects->clock);
+ goto no_clock;
+ }
+
+ dev_set_drvdata(&dev->dev, etsects);
+
+ return 0;
+
+no_clock:
+no_ioremap:
+ release_resource(etsects->rsrc);
+no_resource:
+ free_irq(etsects->irq, etsects);
+no_node:
+ kfree(etsects);
+no_memory:
+ return err;
+}
+
+static int gianfar_ptp_remove(struct platform_device *dev)
+{
+ struct etsects *etsects = dev_get_drvdata(&dev->dev);
+
+ gfar_write(&etsects->regs->tmr_temask, 0);
+ gfar_write(&etsects->regs->tmr_ctrl, 0);
+
+ ptp_clock_unregister(etsects->clock);
+ iounmap(etsects->regs);
+ release_resource(etsects->rsrc);
+ free_irq(etsects->irq, etsects);
+ kfree(etsects);
+
+ return 0;
+}
+
+static struct of_device_id match_table[] = {
+ { .compatible = "fsl,etsec-ptp" },
+ {},
+};
+
+static struct platform_driver gianfar_ptp_driver = {
+ .driver = {
+ .name = "gianfar_ptp",
+ .of_match_table = match_table,
+ .owner = THIS_MODULE,
+ },
+ .probe = gianfar_ptp_probe,
+ .remove = gianfar_ptp_remove,
+};
+
+/* module operations */
+
+static int __init ptp_gianfar_init(void)
+{
+ return platform_driver_register(&gianfar_ptp_driver);
+}
+
+module_init(ptp_gianfar_init);
+
+static void __exit ptp_gianfar_exit(void)
+{
+ platform_driver_unregister(&gianfar_ptp_driver);
+}
+
+module_exit(ptp_gianfar_exit);
+
+MODULE_AUTHOR("Richard Cochran <richard.cochran@omicron.at>");
+MODULE_DESCRIPTION("PTP clock using the eTSEC");
+MODULE_LICENSE("GPL");