drivers/hwtracing/coresight/coresight-cti-core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2018 Linaro Limited, All rights reserved.
   4  * Author: Mike Leach <mike.leach@linaro.org>
   5  */
   6
   7 #include <linux/amba/bus.h>
   8 #include <linux/atomic.h>
   9 #include <linux/bits.h>
  10 #include <linux/coresight.h>
  11 #include <linux/cpu_pm.h>
  12 #include <linux/cpuhotplug.h>
  13 #include <linux/device.h>
  14 #include <linux/io.h>
  15 #include <linux/kernel.h>
  16 #include <linux/list.h>
  17 #include <linux/mutex.h>
  18 #include <linux/pm_runtime.h>
  19 #include <linux/property.h>
  20 #include <linux/spinlock.h>
  21
  22 #include "coresight-priv.h"
  23 #include "coresight-cti.h"
  24
  25 /**
  26  * CTI devices can be associated with a PE, or be connected to CoreSight
  27  * hardware. We have a list of all CTIs irrespective of CPU bound or
  28  * otherwise.
  29  *
  30  * We assume that the non-CPU CTIs are always powered as we do with sinks etc.
  31  *
  32  * We leave the client to figure out if all the CTIs are interconnected with
  33  * the same CTM, in general this is the case but does not always have to be.
  34  */
  35
  36 /* net of CTI devices connected via CTM */
  37 static LIST_HEAD(ect_net);
  38
  39 /* protect the list */
  40 static DEFINE_MUTEX(ect_mutex);
  41
  42 #define csdev_to_cti_drvdata(csdev)     \
  43         dev_get_drvdata(csdev->dev.parent)
  44
  45 /* power management handling */
  46 static int nr_cti_cpu;
  47
  48 /* quick lookup list for CPU bound CTIs when power handling */
  49 static struct cti_drvdata *cti_cpu_drvdata[NR_CPUS];
  50
  51 /*
  52  * CTI naming. CTI bound to cores will have the name cti_cpu<N> where
  53  * N is the CPU ID. System CTIs will have the name cti_sys<I> where I
  54  * is an index allocated by order of discovery.
  55  *
  56  * CTI device name list - for CTI not bound to cores.
  57  */
  58 DEFINE_CORESIGHT_DEVLIST(cti_sys_devs, "cti_sys");
  59
  60 /* write set of regs to hardware - call with spinlock claimed */
  61 void cti_write_all_hw_regs(struct cti_drvdata *drvdata)
  62 {
  63         struct cti_config *config = &drvdata->config;
  64         int i;
  65
  66         CS_UNLOCK(drvdata->base);
  67
  68         /* disable CTI before writing registers */
  69         writel_relaxed(0, drvdata->base + CTICONTROL);
  70
  71         /* write the CTI trigger registers */
  72         for (i = 0; i < config->nr_trig_max; i++) {
  73                 writel_relaxed(config->ctiinen[i], drvdata->base + CTIINEN(i));
  74                 writel_relaxed(config->ctiouten[i],
  75                                drvdata->base + CTIOUTEN(i));
  76         }
  77
  78         /* other regs */
  79         writel_relaxed(config->ctigate, drvdata->base + CTIGATE);
  80         writel_relaxed(config->asicctl, drvdata->base + ASICCTL);
  81         writel_relaxed(config->ctiappset, drvdata->base + CTIAPPSET);
  82
  83         /* re-enable CTI */
  84         writel_relaxed(1, drvdata->base + CTICONTROL);
  85
  86         CS_LOCK(drvdata->base);
  87 }
  88
  89 /* write regs to hardware and enable */
  90 static int cti_enable_hw(struct cti_drvdata *drvdata)
  91 {
  92         struct cti_config *config = &drvdata->config;
  93         struct device *dev = &drvdata->csdev->dev;
  94         unsigned long flags;
  95         int rc = 0;
  96
  97         pm_runtime_get_sync(dev->parent);
  98         spin_lock_irqsave(&drvdata->spinlock, flags);
  99
 100         /* no need to do anything if enabled or unpowered*/
 101         if (config->hw_enabled || !config->hw_powered)
 102                 goto cti_state_unchanged;
 103
 104         /* claim the device */
 105         rc = coresight_claim_device(drvdata->csdev);
 106         if (rc)
 107                 goto cti_err_not_enabled;
 108
 109         cti_write_all_hw_regs(drvdata);
 110
 111         config->hw_enabled = true;
 112         atomic_inc(&drvdata->config.enable_req_count);
 113         spin_unlock_irqrestore(&drvdata->spinlock, flags);
 114         return rc;
 115
 116 cti_state_unchanged:
 117         atomic_inc(&drvdata->config.enable_req_count);
 118
 119         /* cannot enable due to error */
 120 cti_err_not_enabled:
 121         spin_unlock_irqrestore(&drvdata->spinlock, flags);
 122         pm_runtime_put(dev->parent);
 123         return rc;
 124 }
 125
 126 /* re-enable CTI on CPU when using CPU hotplug */
 127 static void cti_cpuhp_enable_hw(struct cti_drvdata *drvdata)
 128 {
 129         struct cti_config *config = &drvdata->config;
 130
 131         spin_lock(&drvdata->spinlock);
 132         config->hw_powered = true;
 133
 134         /* no need to do anything if no enable request */
 135         if (!atomic_read(&drvdata->config.enable_req_count))
 136                 goto cti_hp_not_enabled;
 137
 138         /* try to claim the device */
 139         if (coresight_claim_device(drvdata->csdev))
 140                 goto cti_hp_not_enabled;
 141
 142         cti_write_all_hw_regs(drvdata);
 143         config->hw_enabled = true;
 144         spin_unlock(&drvdata->spinlock);
 145         return;
 146
 147         /* did not re-enable due to no claim / no request */
 148 cti_hp_not_enabled:
 149         spin_unlock(&drvdata->spinlock);
 150 }
 151
 152 /* disable hardware */
 153 static int cti_disable_hw(struct cti_drvdata *drvdata)
 154 {
 155         struct cti_config *config = &drvdata->config;
 156         struct device *dev = &drvdata->csdev->dev;
 157         struct coresight_device *csdev = drvdata->csdev;
 158
 159         spin_lock(&drvdata->spinlock);
 160
 161         /* check refcount - disable on 0 */
 162         if (atomic_dec_return(&drvdata->config.enable_req_count) > 0)
 163                 goto cti_not_disabled;
 164
 165         /* no need to do anything if disabled or cpu unpowered */
 166         if (!config->hw_enabled || !config->hw_powered)
 167                 goto cti_not_disabled;
 168
 169         CS_UNLOCK(drvdata->base);
 170
 171         /* disable CTI */
 172         writel_relaxed(0, drvdata->base + CTICONTROL);
 173         config->hw_enabled = false;
 174
 175         coresight_disclaim_device_unlocked(csdev);
 176         CS_LOCK(drvdata->base);
 177         spin_unlock(&drvdata->spinlock);
 178         pm_runtime_put(dev->parent);
 179         return 0;
 180
 181         /* not disabled this call */
 182 cti_not_disabled:
 183         spin_unlock(&drvdata->spinlock);
 184         return 0;
 185 }
 186
 187 void cti_write_single_reg(struct cti_drvdata *drvdata, int offset, u32 value)
 188 {
 189         CS_UNLOCK(drvdata->base);
 190         writel_relaxed(value, drvdata->base + offset);
 191         CS_LOCK(drvdata->base);
 192 }
 193
 194 void cti_write_intack(struct device *dev, u32 ackval)
 195 {
 196         struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
 197         struct cti_config *config = &drvdata->config;
 198
 199         spin_lock(&drvdata->spinlock);
 200         /* write if enabled */
 201         if (cti_active(config))
 202                 cti_write_single_reg(drvdata, CTIINTACK, ackval);
 203         spin_unlock(&drvdata->spinlock);
 204 }
 205
 206 /*
 207  * Look at the HW DEVID register for some of the HW settings.
 208  * DEVID[15:8] - max number of in / out triggers.
 209  */
 210 #define CTI_DEVID_MAXTRIGS(devid_val) ((int) BMVAL(devid_val, 8, 15))
 211
 212 /* DEVID[19:16] - number of CTM channels */
 213 #define CTI_DEVID_CTMCHANNELS(devid_val) ((int) BMVAL(devid_val, 16, 19))
 214
 215 static void cti_set_default_config(struct device *dev,
 216                                    struct cti_drvdata *drvdata)
 217 {
 218         struct cti_config *config = &drvdata->config;
 219         u32 devid;
 220
 221         devid = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
 222         config->nr_trig_max = CTI_DEVID_MAXTRIGS(devid);
 223
 224         /*
 225          * no current hardware should exceed this, but protect the driver
 226          * in case of fault / out of spec hw
 227          */
 228         if (config->nr_trig_max > CTIINOUTEN_MAX) {
 229                 dev_warn_once(dev,
 230                         "Limiting HW MaxTrig value(%d) to driver max(%d)\n",
 231                         config->nr_trig_max, CTIINOUTEN_MAX);
 232                 config->nr_trig_max = CTIINOUTEN_MAX;
 233         }
 234
 235         config->nr_ctm_channels = CTI_DEVID_CTMCHANNELS(devid);
 236
 237         /* Most regs default to 0 as zalloc'ed except...*/
 238         config->trig_filter_enable = true;
 239         config->ctigate = GENMASK(config->nr_ctm_channels - 1, 0);
 240         atomic_set(&config->enable_req_count, 0);
 241 }
 242
 243 /*
 244  * Add a connection entry to the list of connections for this
 245  * CTI device.
 246  */
 247 int cti_add_connection_entry(struct device *dev, struct cti_drvdata *drvdata,
 248                              struct cti_trig_con *tc,
 249                              struct coresight_device *csdev,
 250                              const char *assoc_dev_name)
 251 {
 252         struct cti_device *cti_dev = &drvdata->ctidev;
 253
 254         tc->con_dev = csdev;
 255         /*
 256          * Prefer actual associated CS device dev name to supplied value -
 257          * which is likely to be node name / other conn name.
 258          */
 259         if (csdev)
 260                 tc->con_dev_name = dev_name(&csdev->dev);
 261         else if (assoc_dev_name != NULL) {
 262                 tc->con_dev_name = devm_kstrdup(dev,
 263                                                 assoc_dev_name, GFP_KERNEL);
 264                 if (!tc->con_dev_name)
 265                         return -ENOMEM;
 266         }
 267         list_add_tail(&tc->node, &cti_dev->trig_cons);
 268         cti_dev->nr_trig_con++;
 269
 270         /* add connection usage bit info to overall info */
 271         drvdata->config.trig_in_use |= tc->con_in->used_mask;
 272         drvdata->config.trig_out_use |= tc->con_out->used_mask;
 273
 274         return 0;
 275 }
 276
 277 /* create a trigger connection with appropriately sized signal groups */
 278 struct cti_trig_con *cti_allocate_trig_con(struct device *dev, int in_sigs,
 279                                            int out_sigs)
 280 {
 281         struct cti_trig_con *tc = NULL;
 282         struct cti_trig_grp *in = NULL, *out = NULL;
 283
 284         tc = devm_kzalloc(dev, sizeof(struct cti_trig_con), GFP_KERNEL);
 285         if (!tc)
 286                 return tc;
 287
 288         in = devm_kzalloc(dev,
 289                           offsetof(struct cti_trig_grp, sig_types[in_sigs]),
 290                           GFP_KERNEL);
 291         if (!in)
 292                 return NULL;
 293
 294         out = devm_kzalloc(dev,
 295                            offsetof(struct cti_trig_grp, sig_types[out_sigs]),
 296                            GFP_KERNEL);
 297         if (!out)
 298                 return NULL;
 299
 300         tc->con_in = in;
 301         tc->con_out = out;
 302         tc->con_in->nr_sigs = in_sigs;
 303         tc->con_out->nr_sigs = out_sigs;
 304         return tc;
 305 }
 306
 307 /*
 308  * Add a default connection if nothing else is specified.
 309  * single connection based on max in/out info, no assoc device
 310  */
 311 int cti_add_default_connection(struct device *dev, struct cti_drvdata *drvdata)
 312 {
 313         int ret = 0;
 314         int n_trigs = drvdata->config.nr_trig_max;
 315         u32 n_trig_mask = GENMASK(n_trigs - 1, 0);
 316         struct cti_trig_con *tc = NULL;
 317
 318         /*
 319          * Assume max trigs for in and out,
 320          * all used, default sig types allocated
 321          */
 322         tc = cti_allocate_trig_con(dev, n_trigs, n_trigs);
 323         if (!tc)
 324                 return -ENOMEM;
 325
 326         tc->con_in->used_mask = n_trig_mask;
 327         tc->con_out->used_mask = n_trig_mask;
 328         ret = cti_add_connection_entry(dev, drvdata, tc, NULL, "default");
 329         return ret;
 330 }
 331
 332 /** cti channel api **/
 333 /* attach/detach channel from trigger - write through if enabled. */
 334 int cti_channel_trig_op(struct device *dev, enum cti_chan_op op,
 335                         enum cti_trig_dir direction, u32 channel_idx,
 336                         u32 trigger_idx)
 337 {
 338         struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
 339         struct cti_config *config = &drvdata->config;
 340         u32 trig_bitmask;
 341         u32 chan_bitmask;
 342         u32 reg_value;
 343         int reg_offset;
 344
 345         /* ensure indexes in range */
 346         if ((channel_idx >= config->nr_ctm_channels) ||
 347            (trigger_idx >= config->nr_trig_max))
 348                 return -EINVAL;
 349
 350         trig_bitmask = BIT(trigger_idx);
 351
 352         /* ensure registered triggers and not out filtered */
 353         if (direction == CTI_TRIG_IN)   {
 354                 if (!(trig_bitmask & config->trig_in_use))
 355                         return -EINVAL;
 356         } else {
 357                 if (!(trig_bitmask & config->trig_out_use))
 358                         return -EINVAL;
 359
 360                 if ((config->trig_filter_enable) &&
 361                     (config->trig_out_filter & trig_bitmask))
 362                         return -EINVAL;
 363         }
 364
 365         /* update the local register values */
 366         chan_bitmask = BIT(channel_idx);
 367         reg_offset = (direction == CTI_TRIG_IN ? CTIINEN(trigger_idx) :
 368                       CTIOUTEN(trigger_idx));
 369
 370         spin_lock(&drvdata->spinlock);
 371
 372         /* read - modify write - the trigger / channel enable value */
 373         reg_value = direction == CTI_TRIG_IN ? config->ctiinen[trigger_idx] :
 374                      config->ctiouten[trigger_idx];
 375         if (op == CTI_CHAN_ATTACH)
 376                 reg_value |= chan_bitmask;
 377         else
 378                 reg_value &= ~chan_bitmask;
 379
 380         /* write local copy */
 381         if (direction == CTI_TRIG_IN)
 382                 config->ctiinen[trigger_idx] = reg_value;
 383         else
 384                 config->ctiouten[trigger_idx] = reg_value;
 385
 386         /* write through if enabled */
 387         if (cti_active(config))
 388                 cti_write_single_reg(drvdata, reg_offset, reg_value);
 389         spin_unlock(&drvdata->spinlock);
 390         return 0;
 391 }
 392
 393 int cti_channel_gate_op(struct device *dev, enum cti_chan_gate_op op,
 394                         u32 channel_idx)
 395 {
 396         struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
 397         struct cti_config *config = &drvdata->config;
 398         u32 chan_bitmask;
 399         u32 reg_value;
 400         int err = 0;
 401
 402         if (channel_idx >= config->nr_ctm_channels)
 403                 return -EINVAL;
 404
 405         chan_bitmask = BIT(channel_idx);
 406
 407         spin_lock(&drvdata->spinlock);
 408         reg_value = config->ctigate;
 409         switch (op) {
 410         case CTI_GATE_CHAN_ENABLE:
 411                 reg_value |= chan_bitmask;
 412                 break;
 413
 414         case CTI_GATE_CHAN_DISABLE:
 415                 reg_value &= ~chan_bitmask;
 416                 break;
 417
 418         default:
 419                 err = -EINVAL;
 420                 break;
 421         }
 422         if (err == 0) {
 423                 config->ctigate = reg_value;
 424                 if (cti_active(config))
 425                         cti_write_single_reg(drvdata, CTIGATE, reg_value);
 426         }
 427         spin_unlock(&drvdata->spinlock);
 428         return err;
 429 }
 430
 431 int cti_channel_setop(struct device *dev, enum cti_chan_set_op op,
 432                       u32 channel_idx)
 433 {
 434         struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
 435         struct cti_config *config = &drvdata->config;
 436         u32 chan_bitmask;
 437         u32 reg_value;
 438         u32 reg_offset;
 439         int err = 0;
 440
 441         if (channel_idx >= config->nr_ctm_channels)
 442                 return -EINVAL;
 443
 444         chan_bitmask = BIT(channel_idx);
 445
 446         spin_lock(&drvdata->spinlock);
 447         reg_value = config->ctiappset;
 448         switch (op) {
 449         case CTI_CHAN_SET:
 450                 config->ctiappset |= chan_bitmask;
 451                 reg_value  = config->ctiappset;
 452                 reg_offset = CTIAPPSET;
 453                 break;
 454
 455         case CTI_CHAN_CLR:
 456                 config->ctiappset &= ~chan_bitmask;
 457                 reg_value = chan_bitmask;
 458                 reg_offset = CTIAPPCLEAR;
 459                 break;
 460
 461         case CTI_CHAN_PULSE:
 462                 config->ctiappset &= ~chan_bitmask;
 463                 reg_value = chan_bitmask;
 464                 reg_offset = CTIAPPPULSE;
 465                 break;
 466
 467         default:
 468                 err = -EINVAL;
 469                 break;
 470         }
 471
 472         if ((err == 0) && cti_active(config))
 473                 cti_write_single_reg(drvdata, reg_offset, reg_value);
 474         spin_unlock(&drvdata->spinlock);
 475
 476         return err;
 477 }
 478
 479 static bool cti_add_sysfs_link(struct cti_drvdata *drvdata,
 480                                struct cti_trig_con *tc)
 481 {
 482         struct coresight_sysfs_link link_info;
 483         int link_err = 0;
 484
 485         link_info.orig = drvdata->csdev;
 486         link_info.orig_name = tc->con_dev_name;
 487         link_info.target = tc->con_dev;
 488         link_info.target_name = dev_name(&drvdata->csdev->dev);
 489
 490         link_err = coresight_add_sysfs_link(&link_info);
 491         if (link_err)
 492                 dev_warn(&drvdata->csdev->dev,
 493                          "Failed to set CTI sysfs link %s<=>%s\n",
 494                          link_info.orig_name, link_info.target_name);
 495         return !link_err;
 496 }
 497
 498 static void cti_remove_sysfs_link(struct cti_drvdata *drvdata,
 499                                   struct cti_trig_con *tc)
 500 {
 501         struct coresight_sysfs_link link_info;
 502
 503         link_info.orig = drvdata->csdev;
 504         link_info.orig_name = tc->con_dev_name;
 505         link_info.target = tc->con_dev;
 506         link_info.target_name = dev_name(&drvdata->csdev->dev);
 507         coresight_remove_sysfs_link(&link_info);
 508 }
 509
 510 /*
 511  * Look for a matching connection device name in the list of connections.
 512  * If found then swap in the csdev name, set trig con association pointer
 513  * and return found.
 514  */
 515 static bool
 516 cti_match_fixup_csdev(struct cti_device *ctidev, const char *node_name,
 517                       struct coresight_device *csdev)
 518 {
 519         struct cti_trig_con *tc;
 520         struct cti_drvdata *drvdata = container_of(ctidev, struct cti_drvdata,
 521                                                    ctidev);
 522
 523         list_for_each_entry(tc, &ctidev->trig_cons, node) {
 524                 if (tc->con_dev_name) {
 525                         if (!strcmp(node_name, tc->con_dev_name)) {
 526                                 /* match: so swap in csdev name & dev */
 527                                 tc->con_dev_name = dev_name(&csdev->dev);
 528                                 tc->con_dev = csdev;
 529                                 /* try to set sysfs link */
 530                                 if (cti_add_sysfs_link(drvdata, tc))
 531                                         return true;
 532                                 /* link failed - remove CTI reference */
 533                                 tc->con_dev = NULL;
 534                                 break;
 535                         }
 536                 }
 537         }
 538         return false;
 539 }
 540
 541 /*
 542  * Search the cti list to add an associated CTI into the supplied CS device
 543  * This will set the association if CTI declared before the CS device.
 544  * (called from coresight_register() with coresight_mutex locked).
 545  */
 546 static void cti_add_assoc_to_csdev(struct coresight_device *csdev)
 547 {
 548         struct cti_drvdata *ect_item;
 549         struct cti_device *ctidev;
 550         const char *node_name = NULL;
 551
 552         /* protect the list */
 553         mutex_lock(&ect_mutex);
 554
 555         /* exit if current is an ECT device.*/
 556         if ((csdev->type == CORESIGHT_DEV_TYPE_ECT) || list_empty(&ect_net))
 557                 goto cti_add_done;
 558
 559         /* if we didn't find the csdev previously we used the fwnode name */
 560         node_name = cti_plat_get_node_name(dev_fwnode(csdev->dev.parent));
 561         if (!node_name)
 562                 goto cti_add_done;
 563
 564         /* for each CTI in list... */
 565         list_for_each_entry(ect_item, &ect_net, node) {
 566                 ctidev = &ect_item->ctidev;
 567                 if (cti_match_fixup_csdev(ctidev, node_name, csdev)) {
 568                         /*
 569                          * if we found a matching csdev then update the ECT
 570                          * association pointer for the device with this CTI.
 571                          */
 572                         csdev->ect_dev = ect_item->csdev;
 573                         break;
 574                 }
 575         }
 576 cti_add_done:
 577         mutex_unlock(&ect_mutex);
 578 }
 579
 580 /*
 581  * Removing the associated devices is easier.
 582  * A CTI will not have a value for csdev->ect_dev.
 583  */
 584 static void cti_remove_assoc_from_csdev(struct coresight_device *csdev)
 585 {
 586         struct cti_drvdata *ctidrv;
 587         struct cti_trig_con *tc;
 588         struct cti_device *ctidev;
 589
 590         mutex_lock(&ect_mutex);
 591         if (csdev->ect_dev) {
 592                 ctidrv = csdev_to_cti_drvdata(csdev->ect_dev);
 593                 ctidev = &ctidrv->ctidev;
 594                 list_for_each_entry(tc, &ctidev->trig_cons, node) {
 595                         if (tc->con_dev == csdev) {
 596                                 cti_remove_sysfs_link(ctidrv, tc);
 597                                 tc->con_dev = NULL;
 598                                 break;
 599                         }
 600                 }
 601                 csdev->ect_dev = NULL;
 602         }
 603         mutex_unlock(&ect_mutex);
 604 }
 605
 606 /*
 607  * Operations to add and remove associated CTI.
 608  * Register to coresight core driver as call back function.
 609  */
 610 static struct cti_assoc_op cti_assoc_ops = {
 611         .add = cti_add_assoc_to_csdev,
 612         .remove = cti_remove_assoc_from_csdev
 613 };
 614
 615 /*
 616  * Update the cross references where the associated device was found
 617  * while we were building the connection info. This will occur if the
 618  * assoc device was registered before the CTI.
 619  */
 620 static void cti_update_conn_xrefs(struct cti_drvdata *drvdata)
 621 {
 622         struct cti_trig_con *tc;
 623         struct cti_device *ctidev = &drvdata->ctidev;
 624
 625         list_for_each_entry(tc, &ctidev->trig_cons, node) {
 626                 if (tc->con_dev) {
 627                         /* if we can set the sysfs link */
 628                         if (cti_add_sysfs_link(drvdata, tc))
 629                                 /* set the CTI/csdev association */
 630                                 coresight_set_assoc_ectdev_mutex(tc->con_dev,
 631                                                          drvdata->csdev);
 632                         else
 633                                 /* otherwise remove reference from CTI */
 634                                 tc->con_dev = NULL;
 635                 }
 636         }
 637 }
 638
 639 static void cti_remove_conn_xrefs(struct cti_drvdata *drvdata)
 640 {
 641         struct cti_trig_con *tc;
 642         struct cti_device *ctidev = &drvdata->ctidev;
 643
 644         list_for_each_entry(tc, &ctidev->trig_cons, node) {
 645                 if (tc->con_dev) {
 646                         coresight_set_assoc_ectdev_mutex(tc->con_dev,
 647                                                          NULL);
 648                         cti_remove_sysfs_link(drvdata, tc);
 649                         tc->con_dev = NULL;
 650                 }
 651         }
 652 }
 653
 654 /** cti PM callbacks **/
 655 static int cti_cpu_pm_notify(struct notifier_block *nb, unsigned long cmd,
 656                              void *v)
 657 {
 658         struct cti_drvdata *drvdata;
 659         struct coresight_device *csdev;
 660         unsigned int cpu = smp_processor_id();
 661         int notify_res = NOTIFY_OK;
 662
 663         if (!cti_cpu_drvdata[cpu])
 664                 return NOTIFY_OK;
 665
 666         drvdata = cti_cpu_drvdata[cpu];
 667         csdev = drvdata->csdev;
 668
 669         if (WARN_ON_ONCE(drvdata->ctidev.cpu != cpu))
 670                 return NOTIFY_BAD;
 671
 672         spin_lock(&drvdata->spinlock);
 673
 674         switch (cmd) {
 675         case CPU_PM_ENTER:
 676                 /* CTI regs all static - we have a copy & nothing to save */
 677                 drvdata->config.hw_powered = false;
 678                 if (drvdata->config.hw_enabled)
 679                         coresight_disclaim_device(csdev);
 680                 break;
 681
 682         case CPU_PM_ENTER_FAILED:
 683                 drvdata->config.hw_powered = true;
 684                 if (drvdata->config.hw_enabled) {
 685                         if (coresight_claim_device(csdev))
 686                                 drvdata->config.hw_enabled = false;
 687                 }
 688                 break;
 689
 690         case CPU_PM_EXIT:
 691                 /* write hardware registers to re-enable. */
 692                 drvdata->config.hw_powered = true;
 693                 drvdata->config.hw_enabled = false;
 694
 695                 /* check enable reference count to enable HW */
 696                 if (atomic_read(&drvdata->config.enable_req_count)) {
 697                         /* check we can claim the device as we re-power */
 698                         if (coresight_claim_device(csdev))
 699                                 goto cti_notify_exit;
 700
 701                         drvdata->config.hw_enabled = true;
 702                         cti_write_all_hw_regs(drvdata);
 703                 }
 704                 break;
 705
 706         default:
 707                 notify_res = NOTIFY_DONE;
 708                 break;
 709         }
 710
 711 cti_notify_exit:
 712         spin_unlock(&drvdata->spinlock);
 713         return notify_res;
 714 }
 715
 716 static struct notifier_block cti_cpu_pm_nb = {
 717         .notifier_call = cti_cpu_pm_notify,
 718 };
 719
 720 /* CPU HP handlers */
 721 static int cti_starting_cpu(unsigned int cpu)
 722 {
 723         struct cti_drvdata *drvdata = cti_cpu_drvdata[cpu];
 724
 725         if (!drvdata)
 726                 return 0;
 727
 728         cti_cpuhp_enable_hw(drvdata);
 729         return 0;
 730 }
 731
 732 static int cti_dying_cpu(unsigned int cpu)
 733 {
 734         struct cti_drvdata *drvdata = cti_cpu_drvdata[cpu];
 735
 736         if (!drvdata)
 737                 return 0;
 738
 739         spin_lock(&drvdata->spinlock);
 740         drvdata->config.hw_powered = false;
 741         if (drvdata->config.hw_enabled)
 742                 coresight_disclaim_device(drvdata->csdev);
 743         spin_unlock(&drvdata->spinlock);
 744         return 0;
 745 }
 746
 747 static int cti_pm_setup(struct cti_drvdata *drvdata)
 748 {
 749         int ret;
 750
 751         if (drvdata->ctidev.cpu == -1)
 752                 return 0;
 753
 754         if (nr_cti_cpu)
 755                 goto done;
 756
 757         cpus_read_lock();
 758         ret = cpuhp_setup_state_nocalls_cpuslocked(
 759                         CPUHP_AP_ARM_CORESIGHT_CTI_STARTING,
 760                         "arm/coresight_cti:starting",
 761                         cti_starting_cpu, cti_dying_cpu);
 762         if (ret) {
 763                 cpus_read_unlock();
 764                 return ret;
 765         }
 766
 767         ret = cpu_pm_register_notifier(&cti_cpu_pm_nb);
 768         cpus_read_unlock();
 769         if (ret) {
 770                 cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_CTI_STARTING);
 771                 return ret;
 772         }
 773
 774 done:
 775         nr_cti_cpu++;
 776         cti_cpu_drvdata[drvdata->ctidev.cpu] = drvdata;
 777
 778         return 0;
 779 }
 780
 781 /* release PM registrations */
 782 static void cti_pm_release(struct cti_drvdata *drvdata)
 783 {
 784         if (drvdata->ctidev.cpu == -1)
 785                 return;
 786
 787         cti_cpu_drvdata[drvdata->ctidev.cpu] = NULL;
 788         if (--nr_cti_cpu == 0) {
 789                 cpu_pm_unregister_notifier(&cti_cpu_pm_nb);
 790                 cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_CTI_STARTING);
 791         }
 792 }
 793
 794 /** cti ect operations **/
 795 int cti_enable(struct coresight_device *csdev)
 796 {
 797         struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev);
 798
 799         return cti_enable_hw(drvdata);
 800 }
 801
 802 int cti_disable(struct coresight_device *csdev)
 803 {
 804         struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev);
 805
 806         return cti_disable_hw(drvdata);
 807 }
 808
 809 static const struct coresight_ops_ect cti_ops_ect = {
 810         .enable = cti_enable,
 811         .disable = cti_disable,
 812 };
 813
 814 static const struct coresight_ops cti_ops = {
 815         .ect_ops = &cti_ops_ect,
 816 };
 817
 818 /*
 819  * Free up CTI specific resources
 820  * called by dev->release, need to call down to underlying csdev release.
 821  */
 822 static void cti_device_release(struct device *dev)
 823 {
 824         struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
 825         struct cti_drvdata *ect_item, *ect_tmp;
 826
 827         mutex_lock(&ect_mutex);
 828         cti_pm_release(drvdata);
 829
 830         /* remove from the list */
 831         list_for_each_entry_safe(ect_item, ect_tmp, &ect_net, node) {
 832                 if (ect_item == drvdata) {
 833                         list_del(&ect_item->node);
 834                         break;
 835                 }
 836         }
 837         mutex_unlock(&ect_mutex);
 838
 839         if (drvdata->csdev_release)
 840                 drvdata->csdev_release(dev);
 841 }
 842 static void cti_remove(struct amba_device *adev)
 843 {
 844         struct cti_drvdata *drvdata = dev_get_drvdata(&adev->dev);
 845
 846         mutex_lock(&ect_mutex);
 847         cti_remove_conn_xrefs(drvdata);
 848         mutex_unlock(&ect_mutex);
 849
 850         coresight_unregister(drvdata->csdev);
 851 }
 852
 853 static int cti_probe(struct amba_device *adev, const struct amba_id *id)
 854 {
 855         int ret = 0;
 856         void __iomem *base;
 857         struct device *dev = &adev->dev;
 858         struct cti_drvdata *drvdata = NULL;
 859         struct coresight_desc cti_desc;
 860         struct coresight_platform_data *pdata = NULL;
 861         struct resource *res = &adev->res;
 862
 863         /* driver data*/
 864         drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
 865         if (!drvdata)
 866                 return -ENOMEM;
 867
 868         /* Validity for the resource is already checked by the AMBA core */
 869         base = devm_ioremap_resource(dev, res);
 870         if (IS_ERR(base))
 871                 return PTR_ERR(base);
 872
 873         drvdata->base = base;
 874         cti_desc.access = CSDEV_ACCESS_IOMEM(base);
 875
 876         dev_set_drvdata(dev, drvdata);
 877
 878         /* default CTI device info  */
 879         drvdata->ctidev.cpu = -1;
 880         drvdata->ctidev.nr_trig_con = 0;
 881         drvdata->ctidev.ctm_id = 0;
 882         INIT_LIST_HEAD(&drvdata->ctidev.trig_cons);
 883
 884         spin_lock_init(&drvdata->spinlock);
 885
 886         /* initialise CTI driver config values */
 887         cti_set_default_config(dev, drvdata);
 888
 889         pdata = coresight_cti_get_platform_data(dev);
 890         if (IS_ERR(pdata)) {
 891                 dev_err(dev, "coresight_cti_get_platform_data err\n");
 892                 return  PTR_ERR(pdata);
 893         }
 894
 895         /* default to powered - could change on PM notifications */
 896         drvdata->config.hw_powered = true;
 897
 898         /* set up device name - will depend if cpu bound or otherwise */
 899         if (drvdata->ctidev.cpu >= 0)
 900                 cti_desc.name = devm_kasprintf(dev, GFP_KERNEL, "cti_cpu%d",
 901                                                drvdata->ctidev.cpu);
 902         else
 903                 cti_desc.name = coresight_alloc_device_name(&cti_sys_devs, dev);
 904         if (!cti_desc.name)
 905                 return -ENOMEM;
 906
 907         /* setup CPU power management handling for CPU bound CTI devices. */
 908         ret = cti_pm_setup(drvdata);
 909         if (ret)
 910                 return ret;
 911
 912         /* create dynamic attributes for connections */
 913         ret = cti_create_cons_sysfs(dev, drvdata);
 914         if (ret) {
 915                 dev_err(dev, "%s: create dynamic sysfs entries failed\n",
 916                         cti_desc.name);
 917                 goto pm_release;
 918         }
 919
 920         /* set up coresight component description */
 921         cti_desc.pdata = pdata;
 922         cti_desc.type = CORESIGHT_DEV_TYPE_ECT;
 923         cti_desc.subtype.ect_subtype = CORESIGHT_DEV_SUBTYPE_ECT_CTI;
 924         cti_desc.ops = &cti_ops;
 925         cti_desc.groups = drvdata->ctidev.con_groups;
 926         cti_desc.dev = dev;
 927         drvdata->csdev = coresight_register(&cti_desc);
 928         if (IS_ERR(drvdata->csdev)) {
 929                 ret = PTR_ERR(drvdata->csdev);
 930                 goto pm_release;
 931         }
 932
 933         /* add to list of CTI devices */
 934         mutex_lock(&ect_mutex);
 935         list_add(&drvdata->node, &ect_net);
 936         /* set any cross references */
 937         cti_update_conn_xrefs(drvdata);
 938         mutex_unlock(&ect_mutex);
 939
 940         /* set up release chain */
 941         drvdata->csdev_release = drvdata->csdev->dev.release;
 942         drvdata->csdev->dev.release = cti_device_release;
 943
 944         /* all done - dec pm refcount */
 945         pm_runtime_put(&adev->dev);
 946         dev_info(&drvdata->csdev->dev, "CTI initialized\n");
 947         return 0;
 948
 949 pm_release:
 950         cti_pm_release(drvdata);
 951         return ret;
 952 }
 953
 954 static struct amba_cs_uci_id uci_id_cti[] = {
 955         {
 956                 /*  CTI UCI data */
 957                 .devarch        = 0x47701a14, /* CTI v2 */
 958                 .devarch_mask   = 0xfff0ffff,
 959                 .devtype        = 0x00000014, /* maj(0x4-debug) min(0x1-ECT) */
 960         }
 961 };
 962
 963 static const struct amba_id cti_ids[] = {
 964         CS_AMBA_ID(0x000bb906), /* Coresight CTI (SoC 400), C-A72, C-A57 */
 965         CS_AMBA_ID(0x000bb922), /* CTI - C-A8 */
 966         CS_AMBA_ID(0x000bb9a8), /* CTI - C-A53 */
 967         CS_AMBA_ID(0x000bb9aa), /* CTI - C-A73 */
 968         CS_AMBA_UCI_ID(0x000bb9da, uci_id_cti), /* CTI - C-A35 */
 969         CS_AMBA_UCI_ID(0x000bb9ed, uci_id_cti), /* Coresight CTI (SoC 600) */
 970         { 0, 0},
 971 };
 972
 973 MODULE_DEVICE_TABLE(amba, cti_ids);
 974
 975 static struct amba_driver cti_driver = {
 976         .drv = {
 977                 .name   = "coresight-cti",
 978                 .owner = THIS_MODULE,
 979                 .suppress_bind_attrs = true,
 980         },
 981         .probe          = cti_probe,
 982         .remove         = cti_remove,
 983         .id_table       = cti_ids,
 984 };
 985
 986 static int __init cti_init(void)
 987 {
 988         int ret;
 989
 990         ret = amba_driver_register(&cti_driver);
 991         if (ret)
 992                 pr_info("Error registering cti driver\n");
 993         coresight_set_cti_ops(&cti_assoc_ops);
 994         return ret;
 995 }
 996
 997 static void __exit cti_exit(void)
 998 {
 999         coresight_remove_cti_ops();
1000         amba_driver_unregister(&cti_driver);
1001 }
1002
1003 module_init(cti_init);
1004 module_exit(cti_exit);
1005
1006 MODULE_AUTHOR("Mike Leach <mike.leach@linaro.org>");
1007 MODULE_DESCRIPTION("Arm CoreSight CTI Driver");
1008 MODULE_LICENSE("GPL v2");