LXR linux/drivers/net/ethernet/freescale/gianfar

   1/*
   2 * PTP 1588 clock using the eTSEC
   3 *
   4 * Copyright (C) 2010 OMICRON electronics GmbH
   5 *
   6 *  This program is free software; you can redistribute it and/or modify
   7 *  it under the terms of the GNU General Public License as published by
   8 *  the Free Software Foundation; either version 2 of the License, or
   9 *  (at your option) any later version.
  10 *
  11 *  This program is distributed in the hope that it will be useful,
  12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 *  GNU General Public License for more details.
  15 *
  16 *  You should have received a copy of the GNU General Public License
  17 *  along with this program; if not, write to the Free Software
  18 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  22
  23#include <linux/device.h>
  24#include <linux/hrtimer.h>
  25#include <linux/interrupt.h>
  26#include <linux/kernel.h>
  27#include <linux/module.h>
  28#include <linux/of.h>
  29#include <linux/of_platform.h>
  30#include <linux/timex.h>
  31#include <linux/io.h>
  32
  33#include <linux/ptp_clock_kernel.h>
  34
  35#include "gianfar.h"
  36
  37/*
  38 * gianfar ptp registers
  39 * Generated by regen.tcl on Thu May 13 01:38:57 PM CEST 2010
  40 */
  41struct gianfar_ptp_registers {
  42        u32 tmr_ctrl;     /* Timer control register */
  43        u32 tmr_tevent;   /* Timestamp event register */
  44        u32 tmr_temask;   /* Timer event mask register */
  45        u32 tmr_pevent;   /* Timestamp event register */
  46        u32 tmr_pemask;   /* Timer event mask register */
  47        u32 tmr_stat;     /* Timestamp status register */
  48        u32 tmr_cnt_h;    /* Timer counter high register */
  49        u32 tmr_cnt_l;    /* Timer counter low register */
  50        u32 tmr_add;      /* Timer drift compensation addend register */
  51        u32 tmr_acc;      /* Timer accumulator register */
  52        u32 tmr_prsc;     /* Timer prescale */
  53        u8  res1[4];
  54        u32 tmroff_h;     /* Timer offset high */
  55        u32 tmroff_l;     /* Timer offset low */
  56        u8  res2[8];
  57        u32 tmr_alarm1_h; /* Timer alarm 1 high register */
  58        u32 tmr_alarm1_l; /* Timer alarm 1 high register */
  59        u32 tmr_alarm2_h; /* Timer alarm 2 high register */
  60        u32 tmr_alarm2_l; /* Timer alarm 2 high register */
  61        u8  res3[48];
  62        u32 tmr_fiper1;   /* Timer fixed period interval */
  63        u32 tmr_fiper2;   /* Timer fixed period interval */
  64        u32 tmr_fiper3;   /* Timer fixed period interval */
  65        u8  res4[20];
  66        u32 tmr_etts1_h;  /* Timestamp of general purpose external trigger */
  67        u32 tmr_etts1_l;  /* Timestamp of general purpose external trigger */
  68        u32 tmr_etts2_h;  /* Timestamp of general purpose external trigger */
  69        u32 tmr_etts2_l;  /* Timestamp of general purpose external trigger */
  70};
  71
  72/* Bit definitions for the TMR_CTRL register */
  73#define ALM1P                 (1<<31) /* Alarm1 output polarity */
  74#define ALM2P                 (1<<30) /* Alarm2 output polarity */
  75#define FIPERST               (1<<28) /* FIPER start indication */
  76#define PP1L                  (1<<27) /* Fiper1 pulse loopback mode enabled. */
  77#define PP2L                  (1<<26) /* Fiper2 pulse loopback mode enabled. */
  78#define TCLK_PERIOD_SHIFT     (16) /* 1588 timer reference clock period. */
  79#define TCLK_PERIOD_MASK      (0x3ff)
  80#define RTPE                  (1<<15) /* Record Tx Timestamp to PAL Enable. */
  81#define FRD                   (1<<14) /* FIPER Realignment Disable */
  82#define ESFDP                 (1<<11) /* External Tx/Rx SFD Polarity. */
  83#define ESFDE                 (1<<10) /* External Tx/Rx SFD Enable. */
  84#define ETEP2                 (1<<9) /* External trigger 2 edge polarity */
  85#define ETEP1                 (1<<8) /* External trigger 1 edge polarity */
  86#define COPH                  (1<<7) /* Generated clock output phase. */
  87#define CIPH                  (1<<6) /* External oscillator input clock phase */
  88#define TMSR                  (1<<5) /* Timer soft reset. */
  89#define BYP                   (1<<3) /* Bypass drift compensated clock */
  90#define TE                    (1<<2) /* 1588 timer enable. */
  91#define CKSEL_SHIFT           (0)    /* 1588 Timer reference clock source */
  92#define CKSEL_MASK            (0x3)
  93
  94/* Bit definitions for the TMR_TEVENT register */
  95#define ETS2                  (1<<25) /* External trigger 2 timestamp sampled */
  96#define ETS1                  (1<<24) /* External trigger 1 timestamp sampled */
  97#define ALM2                  (1<<17) /* Current time = alarm time register 2 */
  98#define ALM1                  (1<<16) /* Current time = alarm time register 1 */
  99#define PP1                   (1<<7)  /* periodic pulse generated on FIPER1 */
 100#define PP2                   (1<<6)  /* periodic pulse generated on FIPER2 */
 101#define PP3                   (1<<5)  /* periodic pulse generated on FIPER3 */
 102
 103/* Bit definitions for the TMR_TEMASK register */
 104#define ETS2EN                (1<<25) /* External trigger 2 timestamp enable */
 105#define ETS1EN                (1<<24) /* External trigger 1 timestamp enable */
 106#define ALM2EN                (1<<17) /* Timer ALM2 event enable */
 107#define ALM1EN                (1<<16) /* Timer ALM1 event enable */
 108#define PP1EN                 (1<<7) /* Periodic pulse event 1 enable */
 109#define PP2EN                 (1<<6) /* Periodic pulse event 2 enable */
 110
 111/* Bit definitions for the TMR_PEVENT register */
 112#define TXP2                  (1<<9) /* PTP transmitted timestamp im TXTS2 */
 113#define TXP1                  (1<<8) /* PTP transmitted timestamp in TXTS1 */
 114#define RXP                   (1<<0) /* PTP frame has been received */
 115
 116/* Bit definitions for the TMR_PEMASK register */
 117#define TXP2EN                (1<<9) /* Transmit PTP packet event 2 enable */
 118#define TXP1EN                (1<<8) /* Transmit PTP packet event 1 enable */
 119#define RXPEN                 (1<<0) /* Receive PTP packet event enable */
 120
 121/* Bit definitions for the TMR_STAT register */
 122#define STAT_VEC_SHIFT        (0) /* Timer general purpose status vector */
 123#define STAT_VEC_MASK         (0x3f)
 124
 125/* Bit definitions for the TMR_PRSC register */
 126#define PRSC_OCK_SHIFT        (0) /* Output clock division/prescale factor. */
 127#define PRSC_OCK_MASK         (0xffff)
 128
 129
 130#define DRIVER          "gianfar_ptp"
 131#define DEFAULT_CKSEL   1
 132#define N_EXT_TS        2
 133#define REG_SIZE        sizeof(struct gianfar_ptp_registers)
 134
 135struct etsects {
 136        struct gianfar_ptp_registers __iomem *regs;
 137        spinlock_t lock; /* protects regs */
 138        struct ptp_clock *clock;
 139        struct ptp_clock_info caps;
 140        struct resource *rsrc;
 141        int irq;
 142        u64 alarm_interval; /* for periodic alarm */
 143        u64 alarm_value;
 144        u32 tclk_period;  /* nanoseconds */
 145        u32 tmr_prsc;
 146        u32 tmr_add;
 147        u32 cksel;
 148        u32 tmr_fiper1;
 149        u32 tmr_fiper2;
 150};
 151
 152/*
 153 * Register access functions
 154 */
 155
 156/* Caller must hold etsects->lock. */
 157static u64 tmr_cnt_read(struct etsects *etsects)
 158{
 159        u64 ns;
 160        u32 lo, hi;
 161
 162        lo = gfar_read(&etsects->regs->tmr_cnt_l);
 163        hi = gfar_read(&etsects->regs->tmr_cnt_h);
 164        ns = ((u64) hi) << 32;
 165        ns |= lo;
 166        return ns;
 167}
 168
 169/* Caller must hold etsects->lock. */
 170static void tmr_cnt_write(struct etsects *etsects, u64 ns)
 171{
 172        u32 hi = ns >> 32;
 173        u32 lo = ns & 0xffffffff;
 174
 175        gfar_write(&etsects->regs->tmr_cnt_l, lo);
 176        gfar_write(&etsects->regs->tmr_cnt_h, hi);
 177}
 178
 179/* Caller must hold etsects->lock. */
 180static void set_alarm(struct etsects *etsects)
 181{
 182        u64 ns;
 183        u32 lo, hi;
 184
 185        ns = tmr_cnt_read(etsects) + 1500000000ULL;
 186        ns = div_u64(ns, 1000000000UL) * 1000000000ULL;
 187        ns -= etsects->tclk_period;
 188        hi = ns >> 32;
 189        lo = ns & 0xffffffff;
 190        gfar_write(&etsects->regs->tmr_alarm1_l, lo);
 191        gfar_write(&etsects->regs->tmr_alarm1_h, hi);
 192}
 193
 194/* Caller must hold etsects->lock. */
 195static void set_fipers(struct etsects *etsects)
 196{
 197        set_alarm(etsects);
 198        gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
 199        gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
 200}
 201
 202/*
 203 * Interrupt service routine
 204 */
 205
 206static irqreturn_t isr(int irq, void *priv)
 207{
 208        struct etsects *etsects = priv;
 209        struct ptp_clock_event event;
 210        u64 ns;
 211        u32 ack = 0, lo, hi, mask, val;
 212
 213        val = gfar_read(&etsects->regs->tmr_tevent);
 214
 215        if (val & ETS1) {
 216                ack |= ETS1;
 217                hi = gfar_read(&etsects->regs->tmr_etts1_h);
 218                lo = gfar_read(&etsects->regs->tmr_etts1_l);
 219                event.type = PTP_CLOCK_EXTTS;
 220                event.index = 0;
 221                event.timestamp = ((u64) hi) << 32;
 222                event.timestamp |= lo;
 223                ptp_clock_event(etsects->clock, &event);
 224        }
 225
 226        if (val & ETS2) {
 227                ack |= ETS2;
 228                hi = gfar_read(&etsects->regs->tmr_etts2_h);
 229                lo = gfar_read(&etsects->regs->tmr_etts2_l);
 230                event.type = PTP_CLOCK_EXTTS;
 231                event.index = 1;
 232                event.timestamp = ((u64) hi) << 32;
 233                event.timestamp |= lo;
 234                ptp_clock_event(etsects->clock, &event);
 235        }
 236
 237        if (val & ALM2) {
 238                ack |= ALM2;
 239                if (etsects->alarm_value) {
 240                        event.type = PTP_CLOCK_ALARM;
 241                        event.index = 0;
 242                        event.timestamp = etsects->alarm_value;
 243                        ptp_clock_event(etsects->clock, &event);
 244                }
 245                if (etsects->alarm_interval) {
 246                        ns = etsects->alarm_value + etsects->alarm_interval;
 247                        hi = ns >> 32;
 248                        lo = ns & 0xffffffff;
 249                        spin_lock(&etsects->lock);
 250                        gfar_write(&etsects->regs->tmr_alarm2_l, lo);
 251                        gfar_write(&etsects->regs->tmr_alarm2_h, hi);
 252                        spin_unlock(&etsects->lock);
 253                        etsects->alarm_value = ns;
 254                } else {
 255                        gfar_write(&etsects->regs->tmr_tevent, ALM2);
 256                        spin_lock(&etsects->lock);
 257                        mask = gfar_read(&etsects->regs->tmr_temask);
 258                        mask &= ~ALM2EN;
 259                        gfar_write(&etsects->regs->tmr_temask, mask);
 260                        spin_unlock(&etsects->lock);
 261                        etsects->alarm_value = 0;
 262                        etsects->alarm_interval = 0;
 263                }
 264        }
 265
 266        if (val & PP1) {
 267                ack |= PP1;
 268                event.type = PTP_CLOCK_PPS;
 269                ptp_clock_event(etsects->clock, &event);
 270        }
 271
 272        if (ack) {
 273                gfar_write(&etsects->regs->tmr_tevent, ack);
 274                return IRQ_HANDLED;
 275        } else
 276                return IRQ_NONE;
 277}
 278
 279/*
 280 * PTP clock operations
 281 */
 282
 283static int ptp_gianfar_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
 284{
 285        u64 adj, diff;
 286        u32 tmr_add;
 287        int neg_adj = 0;
 288        struct etsects *etsects = container_of(ptp, struct etsects, caps);
 289
 290        if (scaled_ppm < 0) {
 291                neg_adj = 1;
 292                scaled_ppm = -scaled_ppm;
 293        }
 294        tmr_add = etsects->tmr_add;
 295        adj = tmr_add;
 296
 297        /* calculate diff as adj*(scaled_ppm/65536)/1000000
 298         * and round() to the nearest integer
 299         */
 300        adj *= scaled_ppm;
 301        diff = div_u64(adj, 8000000);
 302        diff = (diff >> 13) + ((diff >> 12) & 1);
 303
 304        tmr_add = neg_adj ? tmr_add - diff : tmr_add + diff;
 305
 306        gfar_write(&etsects->regs->tmr_add, tmr_add);
 307
 308        return 0;
 309}
 310
 311static int ptp_gianfar_adjtime(struct ptp_clock_info *ptp, s64 delta)
 312{
 313        s64 now;
 314        unsigned long flags;
 315        struct etsects *etsects = container_of(ptp, struct etsects, caps);
 316
 317        spin_lock_irqsave(&etsects->lock, flags);
 318
 319        now = tmr_cnt_read(etsects);
 320        now += delta;
 321        tmr_cnt_write(etsects, now);
 322        set_fipers(etsects);
 323
 324        spin_unlock_irqrestore(&etsects->lock, flags);
 325
 326        return 0;
 327}
 328
 329static int ptp_gianfar_gettime(struct ptp_clock_info *ptp,
 330                               struct timespec64 *ts)
 331{
 332        u64 ns;
 333        unsigned long flags;
 334        struct etsects *etsects = container_of(ptp, struct etsects, caps);
 335
 336        spin_lock_irqsave(&etsects->lock, flags);
 337
 338        ns = tmr_cnt_read(etsects);
 339
 340        spin_unlock_irqrestore(&etsects->lock, flags);
 341
 342        *ts = ns_to_timespec64(ns);
 343
 344        return 0;
 345}
 346
 347static int ptp_gianfar_settime(struct ptp_clock_info *ptp,
 348                               const struct timespec64 *ts)
 349{
 350        u64 ns;
 351        unsigned long flags;
 352        struct etsects *etsects = container_of(ptp, struct etsects, caps);
 353
 354        ns = timespec64_to_ns(ts);
 355
 356        spin_lock_irqsave(&etsects->lock, flags);
 357
 358        tmr_cnt_write(etsects, ns);
 359        set_fipers(etsects);
 360
 361        spin_unlock_irqrestore(&etsects->lock, flags);
 362
 363        return 0;
 364}
 365
 366static int ptp_gianfar_enable(struct ptp_clock_info *ptp,
 367                              struct ptp_clock_request *rq, int on)
 368{
 369        struct etsects *etsects = container_of(ptp, struct etsects, caps);
 370        unsigned long flags;
 371        u32 bit, mask;
 372
 373        switch (rq->type) {
 374        case PTP_CLK_REQ_EXTTS:
 375                switch (rq->extts.index) {
 376                case 0:
 377                        bit = ETS1EN;
 378                        break;
 379                case 1:
 380                        bit = ETS2EN;
 381                        break;
 382                default:
 383                        return -EINVAL;
 384                }
 385                spin_lock_irqsave(&etsects->lock, flags);
 386                mask = gfar_read(&etsects->regs->tmr_temask);
 387                if (on)
 388                        mask |= bit;
 389                else
 390                        mask &= ~bit;
 391                gfar_write(&etsects->regs->tmr_temask, mask);
 392                spin_unlock_irqrestore(&etsects->lock, flags);
 393                return 0;
 394
 395        case PTP_CLK_REQ_PPS:
 396                spin_lock_irqsave(&etsects->lock, flags);
 397                mask = gfar_read(&etsects->regs->tmr_temask);
 398                if (on)
 399                        mask |= PP1EN;
 400                else
 401                        mask &= ~PP1EN;
 402                gfar_write(&etsects->regs->tmr_temask, mask);
 403                spin_unlock_irqrestore(&etsects->lock, flags);
 404                return 0;
 405
 406        default:
 407                break;
 408        }
 409
 410        return -EOPNOTSUPP;
 411}
 412
 413static const struct ptp_clock_info ptp_gianfar_caps = {
 414        .owner          = THIS_MODULE,
 415        .name           = "gianfar clock",
 416        .max_adj        = 512000,
 417        .n_alarm        = 0,
 418        .n_ext_ts       = N_EXT_TS,
 419        .n_per_out      = 0,
 420        .n_pins         = 0,
 421        .pps            = 1,
 422        .adjfine        = ptp_gianfar_adjfine,
 423        .adjtime        = ptp_gianfar_adjtime,
 424        .gettime64      = ptp_gianfar_gettime,
 425        .settime64      = ptp_gianfar_settime,
 426        .enable         = ptp_gianfar_enable,
 427};
 428
 429static int gianfar_ptp_probe(struct platform_device *dev)
 430{
 431        struct device_node *node = dev->dev.of_node;
 432        struct etsects *etsects;
 433        struct timespec64 now;
 434        int err = -ENOMEM;
 435        u32 tmr_ctrl;
 436        unsigned long flags;
 437
 438        etsects = kzalloc(sizeof(*etsects), GFP_KERNEL);
 439        if (!etsects)
 440                goto no_memory;
 441
 442        err = -ENODEV;
 443
 444        etsects->caps = ptp_gianfar_caps;
 445
 446        if (of_property_read_u32(node, "fsl,cksel", &etsects->cksel))
 447                etsects->cksel = DEFAULT_CKSEL;
 448
 449        if (of_property_read_u32(node,
 450                                 "fsl,tclk-period", &etsects->tclk_period) ||
 451            of_property_read_u32(node,
 452                                 "fsl,tmr-prsc", &etsects->tmr_prsc) ||
 453            of_property_read_u32(node,
 454                                 "fsl,tmr-add", &etsects->tmr_add) ||
 455            of_property_read_u32(node,
 456                                 "fsl,tmr-fiper1", &etsects->tmr_fiper1) ||
 457            of_property_read_u32(node,
 458                                 "fsl,tmr-fiper2", &etsects->tmr_fiper2) ||
 459            of_property_read_u32(node,
 460                                 "fsl,max-adj", &etsects->caps.max_adj)) {
 461                pr_err("device tree node missing required elements\n");
 462                goto no_node;
 463        }
 464
 465        etsects->irq = platform_get_irq(dev, 0);
 466
 467        if (etsects->irq < 0) {
 468                pr_err("irq not in device tree\n");
 469                goto no_node;
 470        }
 471        if (request_irq(etsects->irq, isr, 0, DRIVER, etsects)) {
 472                pr_err("request_irq failed\n");
 473                goto no_node;
 474        }
 475
 476        etsects->rsrc = platform_get_resource(dev, IORESOURCE_MEM, 0);
 477        if (!etsects->rsrc) {
 478                pr_err("no resource\n");
 479                goto no_resource;
 480        }
 481        if (request_resource(&iomem_resource, etsects->rsrc)) {
 482                pr_err("resource busy\n");
 483                goto no_resource;
 484        }
 485
 486        spin_lock_init(&etsects->lock);
 487
 488        etsects->regs = ioremap(etsects->rsrc->start,
 489                                resource_size(etsects->rsrc));
 490        if (!etsects->regs) {
 491                pr_err("ioremap ptp registers failed\n");
 492                goto no_ioremap;
 493        }
 494        getnstimeofday64(&now);
 495        ptp_gianfar_settime(&etsects->caps, &now);
 496
 497        tmr_ctrl =
 498          (etsects->tclk_period & TCLK_PERIOD_MASK) << TCLK_PERIOD_SHIFT |
 499          (etsects->cksel & CKSEL_MASK) << CKSEL_SHIFT;
 500
 501        spin_lock_irqsave(&etsects->lock, flags);
 502
 503        gfar_write(&etsects->regs->tmr_ctrl,   tmr_ctrl);
 504        gfar_write(&etsects->regs->tmr_add,    etsects->tmr_add);
 505        gfar_write(&etsects->regs->tmr_prsc,   etsects->tmr_prsc);
 506        gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
 507        gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
 508        set_alarm(etsects);
 509        gfar_write(&etsects->regs->tmr_ctrl,   tmr_ctrl|FIPERST|RTPE|TE|FRD);
 510
 511        spin_unlock_irqrestore(&etsects->lock, flags);
 512
 513        etsects->clock = ptp_clock_register(&etsects->caps, &dev->dev);
 514        if (IS_ERR(etsects->clock)) {
 515                err = PTR_ERR(etsects->clock);
 516                goto no_clock;
 517        }
 518        gfar_phc_index = ptp_clock_index(etsects->clock);
 519
 520        platform_set_drvdata(dev, etsects);
 521
 522        return 0;
 523
 524no_clock:
 525        iounmap(etsects->regs);
 526no_ioremap:
 527        release_resource(etsects->rsrc);
 528no_resource:
 529        free_irq(etsects->irq, etsects);
 530no_node:
 531        kfree(etsects);
 532no_memory:
 533        return err;
 534}
 535
 536static int gianfar_ptp_remove(struct platform_device *dev)
 537{
 538        struct etsects *etsects = platform_get_drvdata(dev);
 539
 540        gfar_write(&etsects->regs->tmr_temask, 0);
 541        gfar_write(&etsects->regs->tmr_ctrl,   0);
 542
 543        gfar_phc_index = -1;
 544        ptp_clock_unregister(etsects->clock);
 545        iounmap(etsects->regs);
 546        release_resource(etsects->rsrc);
 547        free_irq(etsects->irq, etsects);
 548        kfree(etsects);
 549
 550        return 0;
 551}
 552
 553static const struct of_device_id match_table[] = {
 554        { .compatible = "fsl,etsec-ptp" },
 555        {},
 556};
 557MODULE_DEVICE_TABLE(of, match_table);
 558
 559static struct platform_driver gianfar_ptp_driver = {
 560        .driver = {
 561                .name           = "gianfar_ptp",
 562                .of_match_table = match_table,
 563        },
 564        .probe       = gianfar_ptp_probe,
 565        .remove      = gianfar_ptp_remove,
 566};
 567
 568module_platform_driver(gianfar_ptp_driver);
 569
 570MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
 571MODULE_DESCRIPTION("PTP clock using the eTSEC");
 572MODULE_LICENSE("GPL");
 573