1 // SPDX-License-Identifier: GPL-2.0+ 2 /* PTP 1588 clock using the Renesas Ethernet AVB 3 * 4 * Copyright (C) 2013-2015 Renesas Electronics Corporation 5 * Copyright (C) 2015 Renesas Solutions Corp. 6 * Copyright (C) 2015-2016 Cogent Embedded, Inc. <source@cogentembedded.com> 7 */ 8 9 #include "ravb.h" 10 11 static 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 */ 25 static 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 */ 42 static 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 */ 65 static 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 of 69 * [x-1 to x+1] (x is the configured increment value in 70 * GTI.TIV), it may happen that a comparison match is 71 * 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 */ 91 static 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 } 119 120 static 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 } 140 141 static 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 } 154 155 static 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 } 169 170 static 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 return -EOPNOTSUPP; 184 185 if (req->index) 186 return -EINVAL; 187 188 if (priv->ptp.extts[req->index] == on) 189 return 0; 190 priv->ptp.extts[req->index] = on; 191 192 spin_lock_irqsave(&priv->lock, flags); 193 if (!info->irq_en_dis) 194 ravb_modify(ndev, GIC, GIC_PTCE, on ? GIC_PTCE : 0); 195 else if (on) 196 ravb_write(ndev, GIE_PTCS, GIE); 197 else 198 ravb_write(ndev, GID_PTCD, GID); 199 spin_unlock_irqrestore(&priv->lock, flags); 200 201 return 0; 202 } 203 204 static int ravb_ptp_perout(struct ptp_clock_info *ptp, 205 struct ptp_perout_request *req, int on) 206 { 207 struct ravb_private *priv = container_of(ptp, struct ravb_private, 208 ptp.info); 209 const struct ravb_hw_info *info = priv->info; 210 struct net_device *ndev = priv->ndev; 211 struct ravb_ptp_perout *perout; 212 unsigned long flags; 213 int error = 0; 214 215 /* Reject requests with unsupported flags */ 216 if (req->flags) 217 return -EOPNOTSUPP; 218 219 if (req->index) 220 return -EINVAL; 221 222 if (on) { 223 u64 start_ns; 224 u64 period_ns; 225 226 start_ns = req->start.sec * NSEC_PER_SEC + req->start.nsec; 227 period_ns = req->period.sec * NSEC_PER_SEC + req->period.nsec; 228 229 if (start_ns > U32_MAX) { 230 netdev_warn(ndev, 231 "ptp: start value (nsec) is over limit. Maximum size of start is only 32 bits\n"); 232 return -ERANGE; 233 } 234 235 if (period_ns > U32_MAX) { 236 netdev_warn(ndev, 237 "ptp: period value (nsec) is over limit. Maximum size of period is only 32 bits\n"); 238 return -ERANGE; 239 } 240 241 spin_lock_irqsave(&priv->lock, flags); 242 243 perout = &priv->ptp.perout[req->index]; 244 perout->target = (u32)start_ns; 245 perout->period = (u32)period_ns; 246 error = ravb_ptp_update_compare(priv, (u32)start_ns); 247 if (!error) { 248 /* Unmask interrupt */ 249 if (!info->irq_en_dis) 250 ravb_modify(ndev, GIC, GIC_PTME, GIC_PTME); 251 else 252 ravb_write(ndev, GIE_PTMS0, GIE); 253 } 254 } else { 255 spin_lock_irqsave(&priv->lock, flags); 256 257 perout = &priv->ptp.perout[req->index]; 258 perout->period = 0; 259 260 /* Mask interrupt */ 261 if (!info->irq_en_dis) 262 ravb_modify(ndev, GIC, GIC_PTME, 0); 263 else 264 ravb_write(ndev, GID_PTMD0, GID); 265 } 266 spin_unlock_irqrestore(&priv->lock, flags); 267 268 return error; 269 } 270 271 static int ravb_ptp_enable(struct ptp_clock_info *ptp, 272 struct ptp_clock_request *req, int on) 273 { 274 switch (req->type) { 275 case PTP_CLK_REQ_EXTTS: 276 return ravb_ptp_extts(ptp, &req->extts, on); 277 case PTP_CLK_REQ_PEROUT: 278 return ravb_ptp_perout(ptp, &req->perout, on); 279 default: 280 return -EOPNOTSUPP; 281 } 282 } 283 284 static const struct ptp_clock_info ravb_ptp_info = { 285 .owner = THIS_MODULE, 286 .name = "ravb clock", 287 .max_adj = 50000000, 288 .n_ext_ts = N_EXT_TS, 289 .n_per_out = N_PER_OUT, 290 .adjfine = ravb_ptp_adjfine, 291 .adjtime = ravb_ptp_adjtime, 292 .gettime64 = ravb_ptp_gettime64, 293 .settime64 = ravb_ptp_settime64, 294 .enable = ravb_ptp_enable, 295 }; 296 297 /* Caller must hold the lock */ 298 void ravb_ptp_interrupt(struct net_device *ndev) 299 { 300 struct ravb_private *priv = netdev_priv(ndev); 301 u32 gis = ravb_read(ndev, GIS); 302 303 gis &= ravb_read(ndev, GIC); 304 if (gis & GIS_PTCF) { 305 struct ptp_clock_event event; 306 307 event.type = PTP_CLOCK_EXTTS; 308 event.index = 0; 309 event.timestamp = ravb_read(ndev, GCPT); 310 ptp_clock_event(priv->ptp.clock, &event); 311 } 312 if (gis & GIS_PTMF) { 313 struct ravb_ptp_perout *perout = priv->ptp.perout; 314 315 if (perout->period) { 316 perout->target += perout->period; 317 ravb_ptp_update_compare(priv, perout->target); 318 } 319 } 320 321 ravb_write(ndev, ~(gis | GIS_RESERVED), GIS); 322 } 323 324 void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) 325 { 326 struct ravb_private *priv = netdev_priv(ndev); 327 unsigned long flags; 328 329 priv->ptp.info = ravb_ptp_info; 330 331 priv->ptp.default_addend = ravb_read(ndev, GTI); 332 priv->ptp.current_addend = priv->ptp.default_addend; 333 334 spin_lock_irqsave(&priv->lock, flags); 335 ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); 336 ravb_modify(ndev, GCCR, GCCR_TCSS, GCCR_TCSS_ADJGPTP); 337 spin_unlock_irqrestore(&priv->lock, flags); 338 339 priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); 340 } 341 342 void ravb_ptp_stop(struct net_device *ndev) 343 { 344 struct ravb_private *priv = netdev_priv(ndev); 345 346 ravb_write(ndev, 0, GIC); 347 ravb_write(ndev, 0, GIS); 348 349 ptp_clock_unregister(priv->ptp.clock); 350 } 351