linux/drivers/hwtracing/coresight/coresight-cti-platform.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2019, The Linaro Limited. All rights reserved.
   4 */
   5#include <linux/coresight.h>
   6#include <linux/device.h>
   7#include <linux/err.h>
   8#include <linux/of.h>
   9#include <linux/property.h>
  10#include <linux/slab.h>
  11
  12#include <dt-bindings/arm/coresight-cti-dt.h>
  13
  14#include "coresight-cti.h"
  15#include "coresight-priv.h"
  16
  17/* Number of CTI signals in the v8 architecturally defined connection */
  18#define NR_V8PE_IN_SIGS         2
  19#define NR_V8PE_OUT_SIGS        3
  20#define NR_V8ETM_INOUT_SIGS     4
  21
  22/* CTI device tree trigger connection node keyword */
  23#define CTI_DT_CONNS            "trig-conns"
  24
  25/* CTI device tree connection property keywords */
  26#define CTI_DT_V8ARCH_COMPAT    "arm,coresight-cti-v8-arch"
  27#define CTI_DT_CSDEV_ASSOC      "arm,cs-dev-assoc"
  28#define CTI_DT_TRIGIN_SIGS      "arm,trig-in-sigs"
  29#define CTI_DT_TRIGOUT_SIGS     "arm,trig-out-sigs"
  30#define CTI_DT_TRIGIN_TYPES     "arm,trig-in-types"
  31#define CTI_DT_TRIGOUT_TYPES    "arm,trig-out-types"
  32#define CTI_DT_FILTER_OUT_SIGS  "arm,trig-filters"
  33#define CTI_DT_CONN_NAME        "arm,trig-conn-name"
  34#define CTI_DT_CTM_ID           "arm,cti-ctm-id"
  35
  36#ifdef CONFIG_OF
  37/*
  38 * CTI can be bound to a CPU, or a system device.
  39 * CPU can be declared at the device top level or in a connections node
  40 * so need to check relative to node not device.
  41 */
  42static int of_cti_get_cpu_at_node(const struct device_node *node)
  43{
  44        int cpu;
  45        struct device_node *dn;
  46
  47        if (node == NULL)
  48                return -1;
  49
  50        dn = of_parse_phandle(node, "cpu", 0);
  51        /* CTI affinity defaults to no cpu */
  52        if (!dn)
  53                return -1;
  54        cpu = of_cpu_node_to_id(dn);
  55        of_node_put(dn);
  56
  57        /* No Affinity  if no cpu nodes are found */
  58        return (cpu < 0) ? -1 : cpu;
  59}
  60
  61#else
  62static int of_cti_get_cpu_at_node(const struct device_node *node)
  63{
  64        return -1;
  65}
  66
  67#endif
  68
  69/*
  70 * CTI can be bound to a CPU, or a system device.
  71 * CPU can be declared at the device top level or in a connections node
  72 * so need to check relative to node not device.
  73 */
  74static int cti_plat_get_cpu_at_node(struct fwnode_handle *fwnode)
  75{
  76        if (is_of_node(fwnode))
  77                return of_cti_get_cpu_at_node(to_of_node(fwnode));
  78        return -1;
  79}
  80
  81const char *cti_plat_get_node_name(struct fwnode_handle *fwnode)
  82{
  83        if (is_of_node(fwnode))
  84                return of_node_full_name(to_of_node(fwnode));
  85        return "unknown";
  86}
  87
  88/*
  89 * Extract a name from the fwnode.
  90 * If the device associated with the node is a coresight_device, then return
  91 * that name and the coresight_device pointer, otherwise return the node name.
  92 */
  93static const char *
  94cti_plat_get_csdev_or_node_name(struct fwnode_handle *fwnode,
  95                                struct coresight_device **csdev)
  96{
  97        const char *name = NULL;
  98        *csdev = coresight_find_csdev_by_fwnode(fwnode);
  99        if (*csdev)
 100                name = dev_name(&(*csdev)->dev);
 101        else
 102                name = cti_plat_get_node_name(fwnode);
 103        return name;
 104}
 105
 106static bool cti_plat_node_name_eq(struct fwnode_handle *fwnode,
 107                                  const char *name)
 108{
 109        if (is_of_node(fwnode))
 110                return of_node_name_eq(to_of_node(fwnode), name);
 111        return false;
 112}
 113
 114static int cti_plat_create_v8_etm_connection(struct device *dev,
 115                                             struct cti_drvdata *drvdata)
 116{
 117        int ret = -ENOMEM, i;
 118        struct fwnode_handle *root_fwnode, *cs_fwnode;
 119        const char *assoc_name = NULL;
 120        struct coresight_device *csdev;
 121        struct cti_trig_con *tc = NULL;
 122
 123        root_fwnode = dev_fwnode(dev);
 124        if (IS_ERR_OR_NULL(root_fwnode))
 125                return -EINVAL;
 126
 127        /* Can optionally have an etm node - return if not  */
 128        cs_fwnode = fwnode_find_reference(root_fwnode, CTI_DT_CSDEV_ASSOC, 0);
 129        if (IS_ERR(cs_fwnode))
 130                return 0;
 131
 132        /* allocate memory */
 133        tc = cti_allocate_trig_con(dev, NR_V8ETM_INOUT_SIGS,
 134                                   NR_V8ETM_INOUT_SIGS);
 135        if (!tc)
 136                goto create_v8_etm_out;
 137
 138        /* build connection data */
 139        tc->con_in->used_mask = 0xF0; /* sigs <4,5,6,7> */
 140        tc->con_out->used_mask = 0xF0; /* sigs <4,5,6,7> */
 141
 142        /*
 143         * The EXTOUT type signals from the ETM are connected to a set of input
 144         * triggers on the CTI, the EXTIN being connected to output triggers.
 145         */
 146        for (i = 0; i < NR_V8ETM_INOUT_SIGS; i++) {
 147                tc->con_in->sig_types[i] = ETM_EXTOUT;
 148                tc->con_out->sig_types[i] = ETM_EXTIN;
 149        }
 150
 151        /*
 152         * We look to see if the ETM coresight device associated with this
 153         * handle has been registered with the system - i.e. probed before
 154         * this CTI. If so csdev will be non NULL and we can use the device
 155         * name and pass the csdev to the connection entry function where
 156         * the association will be recorded.
 157         * If not, then simply record the name in the connection data, the
 158         * probing of the ETM will call into the CTI driver API to update the
 159         * association then.
 160         */
 161        assoc_name = cti_plat_get_csdev_or_node_name(cs_fwnode, &csdev);
 162        ret = cti_add_connection_entry(dev, drvdata, tc, csdev, assoc_name);
 163
 164create_v8_etm_out:
 165        fwnode_handle_put(cs_fwnode);
 166        return ret;
 167}
 168
 169/*
 170 * Create an architecturally defined v8 connection
 171 * must have a cpu, can have an ETM.
 172 */
 173static int cti_plat_create_v8_connections(struct device *dev,
 174                                          struct cti_drvdata *drvdata)
 175{
 176        struct cti_device *cti_dev = &drvdata->ctidev;
 177        struct cti_trig_con *tc = NULL;
 178        int cpuid = 0;
 179        char cpu_name_str[16];
 180        int ret = -ENOMEM;
 181
 182        /* Must have a cpu node */
 183        cpuid = cti_plat_get_cpu_at_node(dev_fwnode(dev));
 184        if (cpuid < 0) {
 185                dev_warn(dev,
 186                         "ARM v8 architectural CTI connection: missing cpu\n");
 187                return -EINVAL;
 188        }
 189        cti_dev->cpu = cpuid;
 190
 191        /* Allocate the v8 cpu connection memory */
 192        tc = cti_allocate_trig_con(dev, NR_V8PE_IN_SIGS, NR_V8PE_OUT_SIGS);
 193        if (!tc)
 194                goto of_create_v8_out;
 195
 196        /* Set the v8 PE CTI connection data */
 197        tc->con_in->used_mask = 0x3; /* sigs <0 1> */
 198        tc->con_in->sig_types[0] = PE_DBGTRIGGER;
 199        tc->con_in->sig_types[1] = PE_PMUIRQ;
 200        tc->con_out->used_mask = 0x7; /* sigs <0 1 2 > */
 201        tc->con_out->sig_types[0] = PE_EDBGREQ;
 202        tc->con_out->sig_types[1] = PE_DBGRESTART;
 203        tc->con_out->sig_types[2] = PE_CTIIRQ;
 204        scnprintf(cpu_name_str, sizeof(cpu_name_str), "cpu%d", cpuid);
 205
 206        ret = cti_add_connection_entry(dev, drvdata, tc, NULL, cpu_name_str);
 207        if (ret)
 208                goto of_create_v8_out;
 209
 210        /* Create the v8 ETM associated connection */
 211        ret = cti_plat_create_v8_etm_connection(dev, drvdata);
 212        if (ret)
 213                goto of_create_v8_out;
 214
 215        /* filter pe_edbgreq - PE trigout sig <0> */
 216        drvdata->config.trig_out_filter |= 0x1;
 217
 218of_create_v8_out:
 219        return ret;
 220}
 221
 222static int cti_plat_check_v8_arch_compatible(struct device *dev)
 223{
 224        struct fwnode_handle *fwnode = dev_fwnode(dev);
 225
 226        if (is_of_node(fwnode))
 227                return of_device_is_compatible(to_of_node(fwnode),
 228                                               CTI_DT_V8ARCH_COMPAT);
 229        return 0;
 230}
 231
 232static int cti_plat_count_sig_elements(const struct fwnode_handle *fwnode,
 233                                       const char *name)
 234{
 235        int nr_elem = fwnode_property_count_u32(fwnode, name);
 236
 237        return (nr_elem < 0 ? 0 : nr_elem);
 238}
 239
 240static int cti_plat_read_trig_group(struct cti_trig_grp *tgrp,
 241                                    const struct fwnode_handle *fwnode,
 242                                    const char *grp_name)
 243{
 244        int idx, err = 0;
 245        u32 *values;
 246
 247        if (!tgrp->nr_sigs)
 248                return 0;
 249
 250        values = kcalloc(tgrp->nr_sigs, sizeof(u32), GFP_KERNEL);
 251        if (!values)
 252                return -ENOMEM;
 253
 254        err = fwnode_property_read_u32_array(fwnode, grp_name,
 255                                             values, tgrp->nr_sigs);
 256
 257        if (!err) {
 258                /* set the signal usage mask */
 259                for (idx = 0; idx < tgrp->nr_sigs; idx++)
 260                        tgrp->used_mask |= BIT(values[idx]);
 261        }
 262
 263        kfree(values);
 264        return err;
 265}
 266
 267static int cti_plat_read_trig_types(struct cti_trig_grp *tgrp,
 268                                    const struct fwnode_handle *fwnode,
 269                                    const char *type_name)
 270{
 271        int items, err = 0, nr_sigs;
 272        u32 *values = NULL, i;
 273
 274        /* allocate an array according to number of signals in connection */
 275        nr_sigs = tgrp->nr_sigs;
 276        if (!nr_sigs)
 277                return 0;
 278
 279        /* see if any types have been included in the device description */
 280        items = cti_plat_count_sig_elements(fwnode, type_name);
 281        if (items > nr_sigs)
 282                return -EINVAL;
 283
 284        /* need an array to store the values iff there are any */
 285        if (items) {
 286                values = kcalloc(items, sizeof(u32), GFP_KERNEL);
 287                if (!values)
 288                        return -ENOMEM;
 289
 290                err = fwnode_property_read_u32_array(fwnode, type_name,
 291                                                     values, items);
 292                if (err)
 293                        goto read_trig_types_out;
 294        }
 295
 296        /*
 297         * Match type id to signal index, 1st type to 1st index etc.
 298         * If fewer types than signals default remainder to GEN_IO.
 299         */
 300        for (i = 0; i < nr_sigs; i++) {
 301                if (i < items) {
 302                        tgrp->sig_types[i] =
 303                                values[i] < CTI_TRIG_MAX ? values[i] : GEN_IO;
 304                } else {
 305                        tgrp->sig_types[i] = GEN_IO;
 306                }
 307        }
 308
 309read_trig_types_out:
 310        kfree(values);
 311        return err;
 312}
 313
 314static int cti_plat_process_filter_sigs(struct cti_drvdata *drvdata,
 315                                        const struct fwnode_handle *fwnode)
 316{
 317        struct cti_trig_grp *tg = NULL;
 318        int err = 0, nr_filter_sigs;
 319
 320        nr_filter_sigs = cti_plat_count_sig_elements(fwnode,
 321                                                     CTI_DT_FILTER_OUT_SIGS);
 322        if (nr_filter_sigs == 0)
 323                return 0;
 324
 325        if (nr_filter_sigs > drvdata->config.nr_trig_max)
 326                return -EINVAL;
 327
 328        tg = kzalloc(sizeof(*tg), GFP_KERNEL);
 329        if (!tg)
 330                return -ENOMEM;
 331
 332        err = cti_plat_read_trig_group(tg, fwnode, CTI_DT_FILTER_OUT_SIGS);
 333        if (!err)
 334                drvdata->config.trig_out_filter |= tg->used_mask;
 335
 336        kfree(tg);
 337        return err;
 338}
 339
 340static int cti_plat_create_connection(struct device *dev,
 341                                      struct cti_drvdata *drvdata,
 342                                      struct fwnode_handle *fwnode)
 343{
 344        struct cti_trig_con *tc = NULL;
 345        int cpuid = -1, err = 0;
 346        struct fwnode_handle *cs_fwnode = NULL;
 347        struct coresight_device *csdev = NULL;
 348        const char *assoc_name = "unknown";
 349        char cpu_name_str[16];
 350        int nr_sigs_in, nr_sigs_out;
 351
 352        /* look to see how many in and out signals we have */
 353        nr_sigs_in = cti_plat_count_sig_elements(fwnode, CTI_DT_TRIGIN_SIGS);
 354        nr_sigs_out = cti_plat_count_sig_elements(fwnode, CTI_DT_TRIGOUT_SIGS);
 355
 356        if ((nr_sigs_in > drvdata->config.nr_trig_max) ||
 357            (nr_sigs_out > drvdata->config.nr_trig_max))
 358                return -EINVAL;
 359
 360        tc = cti_allocate_trig_con(dev, nr_sigs_in, nr_sigs_out);
 361        if (!tc)
 362                return -ENOMEM;
 363
 364        /* look for the signals properties. */
 365        err = cti_plat_read_trig_group(tc->con_in, fwnode,
 366                                       CTI_DT_TRIGIN_SIGS);
 367        if (err)
 368                goto create_con_err;
 369
 370        err = cti_plat_read_trig_types(tc->con_in, fwnode,
 371                                       CTI_DT_TRIGIN_TYPES);
 372        if (err)
 373                goto create_con_err;
 374
 375        err = cti_plat_read_trig_group(tc->con_out, fwnode,
 376                                       CTI_DT_TRIGOUT_SIGS);
 377        if (err)
 378                goto create_con_err;
 379
 380        err = cti_plat_read_trig_types(tc->con_out, fwnode,
 381                                       CTI_DT_TRIGOUT_TYPES);
 382        if (err)
 383                goto create_con_err;
 384
 385        err = cti_plat_process_filter_sigs(drvdata, fwnode);
 386        if (err)
 387                goto create_con_err;
 388
 389        /* read the connection name if set - may be overridden by later */
 390        fwnode_property_read_string(fwnode, CTI_DT_CONN_NAME, &assoc_name);
 391
 392        /* associated cpu ? */
 393        cpuid = cti_plat_get_cpu_at_node(fwnode);
 394        if (cpuid >= 0) {
 395                drvdata->ctidev.cpu = cpuid;
 396                scnprintf(cpu_name_str, sizeof(cpu_name_str), "cpu%d", cpuid);
 397                assoc_name = cpu_name_str;
 398        } else {
 399                /* associated device ? */
 400                cs_fwnode = fwnode_find_reference(fwnode,
 401                                                  CTI_DT_CSDEV_ASSOC, 0);
 402                if (!IS_ERR(cs_fwnode)) {
 403                        assoc_name = cti_plat_get_csdev_or_node_name(cs_fwnode,
 404                                                                     &csdev);
 405                        fwnode_handle_put(cs_fwnode);
 406                }
 407        }
 408        /* set up a connection */
 409        err = cti_add_connection_entry(dev, drvdata, tc, csdev, assoc_name);
 410
 411create_con_err:
 412        return err;
 413}
 414
 415static int cti_plat_create_impdef_connections(struct device *dev,
 416                                              struct cti_drvdata *drvdata)
 417{
 418        int rc = 0;
 419        struct fwnode_handle *fwnode = dev_fwnode(dev);
 420        struct fwnode_handle *child = NULL;
 421
 422        if (IS_ERR_OR_NULL(fwnode))
 423                return -EINVAL;
 424
 425        fwnode_for_each_child_node(fwnode, child) {
 426                if (cti_plat_node_name_eq(child, CTI_DT_CONNS))
 427                        rc = cti_plat_create_connection(dev, drvdata,
 428                                                        child);
 429                if (rc != 0)
 430                        break;
 431        }
 432        fwnode_handle_put(child);
 433
 434        return rc;
 435}
 436
 437/* get the hardware configuration & connection data. */
 438static int cti_plat_get_hw_data(struct device *dev, struct cti_drvdata *drvdata)
 439{
 440        int rc = 0;
 441        struct cti_device *cti_dev = &drvdata->ctidev;
 442
 443        /* get any CTM ID - defaults to 0 */
 444        device_property_read_u32(dev, CTI_DT_CTM_ID, &cti_dev->ctm_id);
 445
 446        /* check for a v8 architectural CTI device */
 447        if (cti_plat_check_v8_arch_compatible(dev))
 448                rc = cti_plat_create_v8_connections(dev, drvdata);
 449        else
 450                rc = cti_plat_create_impdef_connections(dev, drvdata);
 451        if (rc)
 452                return rc;
 453
 454        /* if no connections, just add a single default based on max IN-OUT */
 455        if (cti_dev->nr_trig_con == 0)
 456                rc = cti_add_default_connection(dev, drvdata);
 457        return rc;
 458}
 459
 460struct coresight_platform_data *
 461coresight_cti_get_platform_data(struct device *dev)
 462{
 463        int ret = -ENOENT;
 464        struct coresight_platform_data *pdata = NULL;
 465        struct fwnode_handle *fwnode = dev_fwnode(dev);
 466        struct cti_drvdata *drvdata = dev_get_drvdata(dev);
 467
 468        if (IS_ERR_OR_NULL(fwnode))
 469                goto error;
 470
 471        /*
 472         * Alloc platform data but leave it zero init. CTI does not use the
 473         * same connection infrastructuree as trace path components but an
 474         * empty struct enables us to use the standard coresight component
 475         * registration code.
 476         */
 477        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 478        if (!pdata) {
 479                ret = -ENOMEM;
 480                goto error;
 481        }
 482
 483        /* get some CTI specifics */
 484        ret = cti_plat_get_hw_data(dev, drvdata);
 485
 486        if (!ret)
 487                return pdata;
 488error:
 489        return ERR_PTR(ret);
 490}
 491