352 lines · c
1// SPDX-License-Identifier: GPL-2.0+2/* PTP 1588 clock using the Renesas Ethernet AVB3 *4 * Copyright (C) 2013-2015 Renesas Electronics Corporation5 * Copyright (C) 2015 Renesas Solutions Corp.6 * Copyright (C) 2015-2016 Cogent Embedded, Inc. <source@cogentembedded.com>7 */8 9#include "ravb.h"10 11static int ravb_ptp_tcr_request(struct ravb_private *priv, u32 request)12{13 struct net_device *ndev = priv->ndev;14 int error;15 16 error = ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ);17 if (error)18 return error;19 20 ravb_modify(ndev, GCCR, request, request);21 return ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ);22}23 24/* Caller must hold the lock */25static int ravb_ptp_time_read(struct ravb_private *priv, struct timespec64 *ts)26{27 struct net_device *ndev = priv->ndev;28 int error;29 30 error = ravb_ptp_tcr_request(priv, GCCR_TCR_CAPTURE);31 if (error)32 return error;33 34 ts->tv_nsec = ravb_read(ndev, GCT0);35 ts->tv_sec = ravb_read(ndev, GCT1) |36 ((s64)ravb_read(ndev, GCT2) << 32);37 38 return 0;39}40 41/* Caller must hold the lock */42static int ravb_ptp_time_write(struct ravb_private *priv,43 const struct timespec64 *ts)44{45 struct net_device *ndev = priv->ndev;46 int error;47 u32 gccr;48 49 error = ravb_ptp_tcr_request(priv, GCCR_TCR_RESET);50 if (error)51 return error;52 53 gccr = ravb_read(ndev, GCCR);54 if (gccr & GCCR_LTO)55 return -EBUSY;56 ravb_write(ndev, ts->tv_nsec, GTO0);57 ravb_write(ndev, ts->tv_sec, GTO1);58 ravb_write(ndev, (ts->tv_sec >> 32) & 0xffff, GTO2);59 ravb_write(ndev, gccr | GCCR_LTO, GCCR);60 61 return 0;62}63 64/* Caller must hold the lock */65static int ravb_ptp_update_compare(struct ravb_private *priv, u32 ns)66{67 struct net_device *ndev = priv->ndev;68 /* When the comparison value (GPTC.PTCV) is in range of69 * [x-1 to x+1] (x is the configured increment value in70 * GTI.TIV), it may happen that a comparison match is71 * not detected when the timer wraps around.72 */73 u32 gti_ns_plus_1 = (priv->ptp.current_addend >> 20) + 1;74 u32 gccr;75 76 if (ns < gti_ns_plus_1)77 ns = gti_ns_plus_1;78 else if (ns > 0 - gti_ns_plus_1)79 ns = 0 - gti_ns_plus_1;80 81 gccr = ravb_read(ndev, GCCR);82 if (gccr & GCCR_LPTC)83 return -EBUSY;84 ravb_write(ndev, ns, GPTC);85 ravb_write(ndev, gccr | GCCR_LPTC, GCCR);86 87 return 0;88}89 90/* PTP clock operations */91static int ravb_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)92{93 struct ravb_private *priv = container_of(ptp, struct ravb_private,94 ptp.info);95 struct net_device *ndev = priv->ndev;96 unsigned long flags;97 u32 addend;98 u32 gccr;99 100 addend = (u32)adjust_by_scaled_ppm(priv->ptp.default_addend,101 scaled_ppm);102 103 spin_lock_irqsave(&priv->lock, flags);104 105 priv->ptp.current_addend = addend;106 107 gccr = ravb_read(ndev, GCCR);108 if (gccr & GCCR_LTI) {109 spin_unlock_irqrestore(&priv->lock, flags);110 return -EBUSY;111 }112 ravb_write(ndev, addend & GTI_TIV, GTI);113 ravb_write(ndev, gccr | GCCR_LTI, GCCR);114 115 spin_unlock_irqrestore(&priv->lock, flags);116 117 return 0;118}119 120static int ravb_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)121{122 struct ravb_private *priv = container_of(ptp, struct ravb_private,123 ptp.info);124 struct timespec64 ts;125 unsigned long flags;126 int error;127 128 spin_lock_irqsave(&priv->lock, flags);129 error = ravb_ptp_time_read(priv, &ts);130 if (!error) {131 u64 now = ktime_to_ns(timespec64_to_ktime(ts));132 133 ts = ns_to_timespec64(now + delta);134 error = ravb_ptp_time_write(priv, &ts);135 }136 spin_unlock_irqrestore(&priv->lock, flags);137 138 return error;139}140 141static int ravb_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts)142{143 struct ravb_private *priv = container_of(ptp, struct ravb_private,144 ptp.info);145 unsigned long flags;146 int error;147 148 spin_lock_irqsave(&priv->lock, flags);149 error = ravb_ptp_time_read(priv, ts);150 spin_unlock_irqrestore(&priv->lock, flags);151 152 return error;153}154 155static int ravb_ptp_settime64(struct ptp_clock_info *ptp,156 const struct timespec64 *ts)157{158 struct ravb_private *priv = container_of(ptp, struct ravb_private,159 ptp.info);160 unsigned long flags;161 int error;162 163 spin_lock_irqsave(&priv->lock, flags);164 error = ravb_ptp_time_write(priv, ts);165 spin_unlock_irqrestore(&priv->lock, flags);166 167 return error;168}169 170static int ravb_ptp_extts(struct ptp_clock_info *ptp,171 struct ptp_extts_request *req, int on)172{173 struct ravb_private *priv = container_of(ptp, struct ravb_private,174 ptp.info);175 const struct ravb_hw_info *info = priv->info;176 struct net_device *ndev = priv->ndev;177 unsigned long flags;178 179 /* Reject requests with unsupported flags */180 if (req->flags & ~(PTP_ENABLE_FEATURE |181 PTP_RISING_EDGE |182 PTP_FALLING_EDGE |183 PTP_STRICT_FLAGS))184 return -EOPNOTSUPP;185 186 if (req->index)187 return -EINVAL;188 189 if (priv->ptp.extts[req->index] == on)190 return 0;191 priv->ptp.extts[req->index] = on;192 193 spin_lock_irqsave(&priv->lock, flags);194 if (!info->irq_en_dis)195 ravb_modify(ndev, GIC, GIC_PTCE, on ? GIC_PTCE : 0);196 else if (on)197 ravb_write(ndev, GIE_PTCS, GIE);198 else199 ravb_write(ndev, GID_PTCD, GID);200 spin_unlock_irqrestore(&priv->lock, flags);201 202 return 0;203}204 205static int ravb_ptp_perout(struct ptp_clock_info *ptp,206 struct ptp_perout_request *req, int on)207{208 struct ravb_private *priv = container_of(ptp, struct ravb_private,209 ptp.info);210 const struct ravb_hw_info *info = priv->info;211 struct net_device *ndev = priv->ndev;212 struct ravb_ptp_perout *perout;213 unsigned long flags;214 int error = 0;215 216 /* Reject requests with unsupported flags */217 if (req->flags)218 return -EOPNOTSUPP;219 220 if (req->index)221 return -EINVAL;222 223 if (on) {224 u64 start_ns;225 u64 period_ns;226 227 start_ns = req->start.sec * NSEC_PER_SEC + req->start.nsec;228 period_ns = req->period.sec * NSEC_PER_SEC + req->period.nsec;229 230 if (start_ns > U32_MAX) {231 netdev_warn(ndev,232 "ptp: start value (nsec) is over limit. Maximum size of start is only 32 bits\n");233 return -ERANGE;234 }235 236 if (period_ns > U32_MAX) {237 netdev_warn(ndev,238 "ptp: period value (nsec) is over limit. Maximum size of period is only 32 bits\n");239 return -ERANGE;240 }241 242 spin_lock_irqsave(&priv->lock, flags);243 244 perout = &priv->ptp.perout[req->index];245 perout->target = (u32)start_ns;246 perout->period = (u32)period_ns;247 error = ravb_ptp_update_compare(priv, (u32)start_ns);248 if (!error) {249 /* Unmask interrupt */250 if (!info->irq_en_dis)251 ravb_modify(ndev, GIC, GIC_PTME, GIC_PTME);252 else253 ravb_write(ndev, GIE_PTMS0, GIE);254 }255 } else {256 spin_lock_irqsave(&priv->lock, flags);257 258 perout = &priv->ptp.perout[req->index];259 perout->period = 0;260 261 /* Mask interrupt */262 if (!info->irq_en_dis)263 ravb_modify(ndev, GIC, GIC_PTME, 0);264 else265 ravb_write(ndev, GID_PTMD0, GID);266 }267 spin_unlock_irqrestore(&priv->lock, flags);268 269 return error;270}271 272static int ravb_ptp_enable(struct ptp_clock_info *ptp,273 struct ptp_clock_request *req, int on)274{275 switch (req->type) {276 case PTP_CLK_REQ_EXTTS:277 return ravb_ptp_extts(ptp, &req->extts, on);278 case PTP_CLK_REQ_PEROUT:279 return ravb_ptp_perout(ptp, &req->perout, on);280 default:281 return -EOPNOTSUPP;282 }283}284 285static const struct ptp_clock_info ravb_ptp_info = {286 .owner = THIS_MODULE,287 .name = "ravb clock",288 .max_adj = 50000000,289 .n_ext_ts = N_EXT_TS,290 .n_per_out = N_PER_OUT,291 .adjfine = ravb_ptp_adjfine,292 .adjtime = ravb_ptp_adjtime,293 .gettime64 = ravb_ptp_gettime64,294 .settime64 = ravb_ptp_settime64,295 .enable = ravb_ptp_enable,296};297 298/* Caller must hold the lock */299void ravb_ptp_interrupt(struct net_device *ndev)300{301 struct ravb_private *priv = netdev_priv(ndev);302 u32 gis = ravb_read(ndev, GIS);303 304 gis &= ravb_read(ndev, GIC);305 if (gis & GIS_PTCF) {306 struct ptp_clock_event event;307 308 event.type = PTP_CLOCK_EXTTS;309 event.index = 0;310 event.timestamp = ravb_read(ndev, GCPT);311 ptp_clock_event(priv->ptp.clock, &event);312 }313 if (gis & GIS_PTMF) {314 struct ravb_ptp_perout *perout = priv->ptp.perout;315 316 if (perout->period) {317 perout->target += perout->period;318 ravb_ptp_update_compare(priv, perout->target);319 }320 }321 322 ravb_write(ndev, ~(gis | GIS_RESERVED), GIS);323}324 325void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev)326{327 struct ravb_private *priv = netdev_priv(ndev);328 unsigned long flags;329 330 priv->ptp.info = ravb_ptp_info;331 332 priv->ptp.default_addend = ravb_read(ndev, GTI);333 priv->ptp.current_addend = priv->ptp.default_addend;334 335 spin_lock_irqsave(&priv->lock, flags);336 ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ);337 ravb_modify(ndev, GCCR, GCCR_TCSS, GCCR_TCSS_ADJGPTP);338 spin_unlock_irqrestore(&priv->lock, flags);339 340 priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev);341}342 343void ravb_ptp_stop(struct net_device *ndev)344{345 struct ravb_private *priv = netdev_priv(ndev);346 347 ravb_write(ndev, 0, GIC);348 ravb_write(ndev, 0, GIS);349 350 ptp_clock_unregister(priv->ptp.clock);351}352