// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright(C) 2015 Linaro Limited. All rights reserved.
 * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
 */

#include <api/fs/fs.h>
#include <linux/bits.h>
#include <linux/bitops.h>
#include <linux/compiler.h>
#include <linux/coresight-pmu.h>
#include <linux/kernel.h>
#include <linux/log2.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/zalloc.h>

#include "cs-etm.h"
#include "../../../util/debug.h"
#include "../../../util/record.h"
#include "../../../util/auxtrace.h"
#include "../../../util/cpumap.h"
#include "../../../util/event.h"
#include "../../../util/evlist.h"
#include "../../../util/evsel.h"
#include "../../../util/perf_api_probe.h"
#include "../../../util/evsel_config.h"
#include "../../../util/pmus.h"
#include "../../../util/cs-etm.h"
#include <internal/lib.h> // page_size
#include "../../../util/session.h"

#include <errno.h>
#include <stdlib.h>
#include <sys/stat.h>

struct cs_etm_recording {
        struct auxtrace_record  itr;
        struct perf_pmu         *cs_etm_pmu;
        struct evlist           *evlist;
        bool                    snapshot_mode;
        size_t                  snapshot_size;
};

static const char *metadata_etmv3_ro[CS_ETM_PRIV_MAX] = {
        [CS_ETM_ETMCCER]        = "mgmt/etmccer",
        [CS_ETM_ETMIDR]         = "mgmt/etmidr",
};

static const char * const metadata_etmv4_ro[] = {
        [CS_ETMV4_TRCIDR0]              = "trcidr/trcidr0",
        [CS_ETMV4_TRCIDR1]              = "trcidr/trcidr1",
        [CS_ETMV4_TRCIDR2]              = "trcidr/trcidr2",
        [CS_ETMV4_TRCIDR8]              = "trcidr/trcidr8",
        [CS_ETMV4_TRCAUTHSTATUS]        = "mgmt/trcauthstatus",
        [CS_ETMV4_TS_SOURCE]            = "ts_source",
};

static const char * const metadata_ete_ro[] = {
        [CS_ETE_TRCIDR0]                = "trcidr/trcidr0",
        [CS_ETE_TRCIDR1]                = "trcidr/trcidr1",
        [CS_ETE_TRCIDR2]                = "trcidr/trcidr2",
        [CS_ETE_TRCIDR8]                = "trcidr/trcidr8",
        [CS_ETE_TRCAUTHSTATUS]          = "mgmt/trcauthstatus",
        [CS_ETE_TRCDEVARCH]             = "mgmt/trcdevarch",
        [CS_ETE_TS_SOURCE]              = "ts_source",
};

enum cs_etm_version { CS_NOT_PRESENT, CS_ETMV3, CS_ETMV4, CS_ETE };

static bool cs_etm_is_ete(struct perf_pmu *cs_etm_pmu, struct perf_cpu cpu);
static int cs_etm_get_ro(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path, __u64 *val);
static bool cs_etm_pmu_path_exists(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path);

static enum cs_etm_version cs_etm_get_version(struct perf_pmu *cs_etm_pmu,
                                              struct perf_cpu cpu)
{
        if (cs_etm_is_ete(cs_etm_pmu, cpu))
                return CS_ETE;
        else if (cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0]))
                return CS_ETMV4;
        else if (cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_etmv3_ro[CS_ETM_ETMCCER]))
                return CS_ETMV3;

        return CS_NOT_PRESENT;
}

static int cs_etm_validate_context_id(struct perf_pmu *cs_etm_pmu, struct evsel *evsel,
                                      struct perf_cpu cpu)
{
        int err;
        u64 ctxt, ctxt1, ctxt2;
        __u64 trcidr2;

        evsel__get_config_val(evsel, "contextid", &ctxt);
        evsel__get_config_val(evsel, "contextid1", &ctxt1);
        evsel__get_config_val(evsel, "contextid2", &ctxt2);

        if (!ctxt && !ctxt1 && !ctxt2)
                return 0;

        /* Not supported in etmv3 */
        if (cs_etm_get_version(cs_etm_pmu, cpu) == CS_ETMV3) {
                pr_err("%s: contextid not supported in ETMv3, disable with %s/contextid=0/\n",
                       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
                return -EINVAL;
        }

        /* Get a handle on TRCIDR2 */
        err = cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR2], &trcidr2);
        if (err)
                return err;

        if (ctxt1) {
                /*
                 * TRCIDR2.CIDSIZE, bit [9-5], indicates whether contextID
                 * tracing is supported:
                 *  0b00000 Context ID tracing is not supported.
                 *  0b00100 Maximum of 32-bit Context ID size.
                 *  All other values are reserved.
                 */
                if (BMVAL(trcidr2, 5, 9) != 0x4) {
                        pr_err("%s: CONTEXTIDR_EL1 isn't supported, disable with %s/contextid1=0/\n",
                               CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
                        return -EINVAL;
                }
        }

        if (ctxt2) {
                /*
                 * TRCIDR2.VMIDOPT[30:29] != 0 and
                 * TRCIDR2.VMIDSIZE[14:10] == 0b00100 (32bit virtual contextid)
                 * We can't support CONTEXTIDR in VMID if the size of the
                 * virtual context id is < 32bit.
                 * Any value of VMIDSIZE >= 4 (i.e, > 32bit) is fine for us.
                 */
                if (!BMVAL(trcidr2, 29, 30) || BMVAL(trcidr2, 10, 14) < 4) {
                        pr_err("%s: CONTEXTIDR_EL2 isn't supported, disable with %s/contextid2=0/\n",
                               CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
                        return -EINVAL;
                }
        }

        return 0;
}

static int cs_etm_validate_timestamp(struct perf_pmu *cs_etm_pmu, struct evsel *evsel,
                                     struct perf_cpu cpu)
{
        int err;
        u64 val;
        __u64 trcidr0;

        evsel__get_config_val(evsel, "timestamp", &val);
        if (!val)
                return 0;

        if (cs_etm_get_version(cs_etm_pmu, cpu) == CS_ETMV3) {
                pr_err("%s: timestamp not supported in ETMv3, disable with %s/timestamp=0/\n",
                       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
                return -EINVAL;
        }

        /* Get a handle on TRCIRD0 */
        err = cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0], &trcidr0);
        if (err)
                return err;

        /*
         * TRCIDR0.TSSIZE, bit [28-24], indicates whether global timestamping
         * is supported:
         *  0b00000 Global timestamping is not implemented
         *  0b00110 Implementation supports a maximum timestamp of 48bits.
         *  0b01000 Implementation supports a maximum timestamp of 64bits.
         */
        trcidr0 &= GENMASK(28, 24);
        if (!trcidr0)
                return -EINVAL;

        return 0;
}

static struct perf_pmu *cs_etm_get_pmu(struct auxtrace_record *itr)
{
        struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);

        return ptr->cs_etm_pmu;
}

/*
 * Check whether the requested timestamp and contextid options should be
 * available on all requested CPUs and if not, tell the user how to override.
 * The kernel will silently disable any unavailable options so a warning here
 * first is better. In theory the kernel could still disable the option for
 * some other reason so this is best effort only.
 */
static int cs_etm_validate_config(struct perf_pmu *cs_etm_pmu,
                                  struct evsel *evsel)
{
        int idx, err = 0;
        struct perf_cpu_map *event_cpus = evsel->evlist->core.user_requested_cpus;
        struct perf_cpu_map *intersect_cpus;
        struct perf_cpu cpu;

        /*
         * Set option of each CPU we have. In per-cpu case, do the validation
         * for CPUs to work with. In per-thread case, the CPU map has the "any"
         * CPU value. Since the traced program can run on any CPUs in this case,
         * thus don't skip validation.
         */
        if (!perf_cpu_map__has_any_cpu(event_cpus)) {
                struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();

                intersect_cpus = perf_cpu_map__intersect(event_cpus, online_cpus);
                perf_cpu_map__put(online_cpus);
        } else {
                intersect_cpus = perf_cpu_map__new_online_cpus();
        }

        perf_cpu_map__for_each_cpu_skip_any(cpu, idx, intersect_cpus) {
                if (cs_etm_get_version(cs_etm_pmu, cpu) == CS_NOT_PRESENT) {
                        pr_err("%s: Not found on CPU %d. Check hardware and firmware support and that all Coresight drivers are loaded\n",
                               CORESIGHT_ETM_PMU_NAME, cpu.cpu);
                        return -EINVAL;
                }
                err = cs_etm_validate_context_id(cs_etm_pmu, evsel, cpu);
                if (err)
                        break;

                err = cs_etm_validate_timestamp(cs_etm_pmu, evsel, cpu);
                if (err)
                        break;
        }

        perf_cpu_map__put(intersect_cpus);
        return err;
}

static int cs_etm_parse_snapshot_options(struct auxtrace_record *itr,
                                         struct record_opts *opts,
                                         const char *str)
{
        struct cs_etm_recording *ptr =
                                container_of(itr, struct cs_etm_recording, itr);
        unsigned long long snapshot_size = 0;
        char *endptr;

        if (str) {
                snapshot_size = strtoull(str, &endptr, 0);
                if (*endptr || snapshot_size > SIZE_MAX)
                        return -1;
        }

        opts->auxtrace_snapshot_mode = true;
        opts->auxtrace_snapshot_size = snapshot_size;
        ptr->snapshot_size = snapshot_size;

        return 0;
}

/*
 * If the sink name format "@sink_name" is used, lookup the sink by name to convert to
 * "sinkid=sink_hash" format. If the user has already manually provided a hash then
 * "sinkid" isn't overwritten. If neither are provided then the driver will pick the best
 * sink.
 */
static int cs_etm_set_sink_attr(struct perf_pmu *pmu,
                                struct evsel *evsel)
{
        char msg[BUFSIZ], path[PATH_MAX], *sink;
        struct evsel_config_term *term;
        u32 hash;
        int ret;

        list_for_each_entry(term, &evsel->config_terms, list) {
                if (term->type != EVSEL__CONFIG_TERM_DRV_CFG)
                        continue;

                sink = term->val.str;
                snprintf(path, PATH_MAX, "sinks/%s", sink);

                ret = perf_pmu__scan_file(pmu, path, "%x", &hash);
                if (ret != 1) {
                        if (errno == ENOENT)
                                pr_err("Couldn't find sink \"%s\" on event %s\n"
                                       "Missing kernel or device support?\n\n"
                                       "Hint: An appropriate sink will be picked automatically if one isn't specified.\n",
                                       sink, evsel__name(evsel));
                        else
                                pr_err("Failed to set sink \"%s\" on event %s with %d (%s)\n",
                                       sink, evsel__name(evsel), errno,
                                       str_error_r(errno, msg, sizeof(msg)));
                        return ret;
                }

                evsel__set_config_if_unset(evsel, "sinkid", hash);
                return 0;
        }

        return 0;
}

static struct evsel *cs_etm_get_evsel(struct evlist *evlist,
                                      struct perf_pmu *cs_etm_pmu)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel->core.attr.type == cs_etm_pmu->type)
                        return evsel;
        }

        return NULL;
}

static int cs_etm_recording_options(struct auxtrace_record *itr,
                                    struct evlist *evlist,
                                    struct record_opts *opts)
{
        int ret;
        struct cs_etm_recording *ptr =
                                container_of(itr, struct cs_etm_recording, itr);
        struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
        struct evsel *evsel, *cs_etm_evsel = NULL;
        struct perf_cpu_map *cpus = evlist->core.user_requested_cpus;
        bool privileged = perf_event_paranoid_check(-1);
        int err = 0;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel->core.attr.type == cs_etm_pmu->type) {
                        if (cs_etm_evsel) {
                                pr_err("There may be only one %s event\n",
                                       CORESIGHT_ETM_PMU_NAME);
                                return -EINVAL;
                        }
                        cs_etm_evsel = evsel;
                }
        }

        /* no need to continue if at least one event of interest was found */
        if (!cs_etm_evsel)
                return 0;

        ptr->evlist = evlist;
        ptr->snapshot_mode = opts->auxtrace_snapshot_mode;

        if (!record_opts__no_switch_events(opts) &&
            perf_can_record_switch_events())
                opts->record_switch_events = true;

        cs_etm_evsel->needs_auxtrace_mmap = true;
        opts->full_auxtrace = true;

        ret = cs_etm_set_sink_attr(cs_etm_pmu, cs_etm_evsel);
        if (ret)
                return ret;

        if (opts->use_clockid) {
                pr_err("Cannot use clockid (-k option) with %s\n",
                       CORESIGHT_ETM_PMU_NAME);
                return -EINVAL;
        }

        /* we are in snapshot mode */
        if (opts->auxtrace_snapshot_mode) {
                /*
                 * No size were given to '-S' or '-m,', so go with
                 * the default
                 */
                if (!opts->auxtrace_snapshot_size &&
                    !opts->auxtrace_mmap_pages) {
                        if (privileged) {
                                opts->auxtrace_mmap_pages = MiB(4) / page_size;
                        } else {
                                opts->auxtrace_mmap_pages =
                                                        KiB(128) / page_size;
                                if (opts->mmap_pages == UINT_MAX)
                                        opts->mmap_pages = KiB(256) / page_size;
                        }
                } else if (!opts->auxtrace_mmap_pages && !privileged &&
                                                opts->mmap_pages == UINT_MAX) {
                        opts->mmap_pages = KiB(256) / page_size;
                }

                /*
                 * '-m,xyz' was specified but no snapshot size, so make the
                 * snapshot size as big as the auxtrace mmap area.
                 */
                if (!opts->auxtrace_snapshot_size) {
                        opts->auxtrace_snapshot_size =
                                opts->auxtrace_mmap_pages * (size_t)page_size;
                }

                /*
                 * -Sxyz was specified but no auxtrace mmap area, so make the
                 * auxtrace mmap area big enough to fit the requested snapshot
                 * size.
                 */
                if (!opts->auxtrace_mmap_pages) {
                        size_t sz = opts->auxtrace_snapshot_size;

                        sz = round_up(sz, page_size) / page_size;
                        opts->auxtrace_mmap_pages = roundup_pow_of_two(sz);
                }

                /* Snapshot size can't be bigger than the auxtrace area */
                if (opts->auxtrace_snapshot_size >
                                opts->auxtrace_mmap_pages * (size_t)page_size) {
                        pr_err("Snapshot size %zu must not be greater than AUX area tracing mmap size %zu\n",
                               opts->auxtrace_snapshot_size,
                               opts->auxtrace_mmap_pages * (size_t)page_size);
                        return -EINVAL;
                }

                /* Something went wrong somewhere - this shouldn't happen */
                if (!opts->auxtrace_snapshot_size ||
                    !opts->auxtrace_mmap_pages) {
                        pr_err("Failed to calculate default snapshot size and/or AUX area tracing mmap pages\n");
                        return -EINVAL;
                }
        }

        /* Buffer sizes weren't specified with '-m,xyz' so give some defaults */
        if (!opts->auxtrace_mmap_pages) {
                if (privileged) {
                        opts->auxtrace_mmap_pages = MiB(4) / page_size;
                } else {
                        opts->auxtrace_mmap_pages = KiB(128) / page_size;
                        if (opts->mmap_pages == UINT_MAX)
                                opts->mmap_pages = KiB(256) / page_size;
                }
        }

        if (opts->auxtrace_snapshot_mode)
                pr_debug2("%s snapshot size: %zu\n", CORESIGHT_ETM_PMU_NAME,
                          opts->auxtrace_snapshot_size);

        /*
         * To obtain the auxtrace buffer file descriptor, the auxtrace
         * event must come first.
         */
        evlist__to_front(evlist, cs_etm_evsel);

        /*
         * get the CPU on the sample - need it to associate trace ID in the
         * AUX_OUTPUT_HW_ID event, and the AUX event for per-cpu mmaps.
         */
        evsel__set_sample_bit(cs_etm_evsel, CPU);

        /*
         * Also the case of per-cpu mmaps, need the contextID in order to be notified
         * when a context switch happened.
         */
        if (!perf_cpu_map__is_any_cpu_or_is_empty(cpus)) {
                evsel__set_config_if_unset(cs_etm_evsel, "timestamp", 1);
                evsel__set_config_if_unset(cs_etm_evsel, "contextid", 1);
        }

        /*
         * When the option '--timestamp' or '-T' is enabled, the PERF_SAMPLE_TIME
         * bit is set for all events.  In this case, always enable Arm CoreSight
         * timestamp tracing.
         */
        if (opts->sample_time_set)
                evsel__set_config_if_unset(cs_etm_evsel, "timestamp", 1);

        /* Add dummy event to keep tracking */
        err = parse_event(evlist, "dummy:u");
        if (err)
                goto out;
        evsel = evlist__last(evlist);
        evlist__set_tracking_event(evlist, evsel);
        evsel->core.attr.freq = 0;
        evsel->core.attr.sample_period = 1;

        /* In per-cpu case, always need the time of mmap events etc */
        if (!perf_cpu_map__is_any_cpu_or_is_empty(cpus))
                evsel__set_sample_bit(evsel, TIME);

        err = cs_etm_validate_config(cs_etm_pmu, cs_etm_evsel);
out:
        return err;
}

static u64 cs_etm_synth_etmcr(struct auxtrace_record *itr)
{
        struct cs_etm_recording *ptr =
                container_of(itr, struct cs_etm_recording, itr);
        struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
        struct evsel *evsel = cs_etm_get_evsel(ptr->evlist, cs_etm_pmu);
        u64 etmcr = 0;
        u64 val;

        if (!evsel)
                return 0;

        /*
         * Synthesize what the kernel programmed into ETMCR based on
         * what options the event was opened with. This doesn't have to be
         * complete or 100% accurate, not all bits used by OpenCSD anyway.
         */
        if (!evsel__get_config_val(evsel, "cycacc", &val) && val)
                etmcr |= ETMCR_CYC_ACC;
        if (!evsel__get_config_val(evsel, "timestamp", &val) && val)
                etmcr |= ETMCR_TIMESTAMP_EN;
        if (!evsel__get_config_val(evsel, "retstack", &val) && val)
                etmcr |= ETMCR_RETURN_STACK;

        return etmcr;
}

static u64 cs_etmv4_synth_trcconfigr(struct auxtrace_record *itr)
{
        u64 trcconfigr = 0;
        struct cs_etm_recording *ptr =
                container_of(itr, struct cs_etm_recording, itr);
        struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
        struct evsel *evsel = cs_etm_get_evsel(ptr->evlist, cs_etm_pmu);
        u64 val;

        if (!evsel)
                return 0;

        /*
         * Synthesize what the kernel programmed into TRCCONFIGR based on
         * what options the event was opened with. This doesn't have to be
         * complete or 100% accurate, not all bits used by OpenCSD anyway.
         */
        if (!evsel__get_config_val(evsel, "cycacc", &val) && val)
                trcconfigr |= TRCCONFIGR_CCI;
        if (!evsel__get_config_val(evsel, "contextid1", &val) && val)
                trcconfigr |= TRCCONFIGR_CID;
        if (!evsel__get_config_val(evsel, "timestamp", &val) && val)
                trcconfigr |= TRCCONFIGR_TS;
        if (!evsel__get_config_val(evsel, "retstack", &val) && val)
                trcconfigr |= TRCCONFIGR_RS;
        if (!evsel__get_config_val(evsel, "contextid2", &val) && val)
                trcconfigr |= TRCCONFIGR_VMID | TRCCONFIGR_VMIDOPT;
        if (!evsel__get_config_val(evsel, "branch_broadcast", &val) && val)
                trcconfigr |= TRCCONFIGR_BB;

        return trcconfigr;
}

static size_t
cs_etm_info_priv_size(struct auxtrace_record *itr,
                      struct evlist *evlist)
{
        int idx;
        int etmv3 = 0, etmv4 = 0, ete = 0;
        struct perf_cpu_map *event_cpus = evlist->core.user_requested_cpus;
        struct perf_cpu_map *intersect_cpus;
        struct perf_cpu cpu;
        struct perf_pmu *cs_etm_pmu = cs_etm_get_pmu(itr);

        if (!perf_cpu_map__has_any_cpu(event_cpus)) {
                /* cpu map is not "any" CPU , we have specific CPUs to work with */
                struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();

                intersect_cpus = perf_cpu_map__intersect(event_cpus, online_cpus);
                perf_cpu_map__put(online_cpus);
        } else {
                /* Event can be "any" CPU so count all online CPUs. */
                intersect_cpus = perf_cpu_map__new_online_cpus();
        }
        /* Count number of each type of ETM. Don't count if that CPU has CS_NOT_PRESENT. */
        perf_cpu_map__for_each_cpu_skip_any(cpu, idx, intersect_cpus) {
                enum cs_etm_version v = cs_etm_get_version(cs_etm_pmu, cpu);

                ete   += v == CS_ETE;
                etmv4 += v == CS_ETMV4;
                etmv3 += v == CS_ETMV3;
        }
        perf_cpu_map__put(intersect_cpus);

        return (CS_ETM_HEADER_SIZE +
               (ete   * CS_ETE_PRIV_SIZE) +
               (etmv4 * CS_ETMV4_PRIV_SIZE) +
               (etmv3 * CS_ETMV3_PRIV_SIZE));
}

static int cs_etm_get_ro(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path, __u64 *val)
{
        char pmu_path[PATH_MAX];
        int scan;

        /* Get RO metadata from sysfs */
        snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu.cpu, path);

        scan = perf_pmu__scan_file(pmu, pmu_path, "%llx", val);
        if (scan != 1) {
                pr_err("%s: error reading: %s\n", __func__, pmu_path);
                return -EINVAL;
        }

        return 0;
}

static int cs_etm_get_ro_signed(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path,
                                __u64 *out_val)
{
        char pmu_path[PATH_MAX];
        int scan;
        int val = 0;

        /* Get RO metadata from sysfs */
        snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu.cpu, path);

        scan = perf_pmu__scan_file(pmu, pmu_path, "%d", &val);
        if (scan != 1) {
                pr_err("%s: error reading: %s\n", __func__, pmu_path);
                return -EINVAL;
        }

        *out_val = (__u64) val;
        return 0;
}

static bool cs_etm_pmu_path_exists(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path)
{
        char pmu_path[PATH_MAX];

        /* Get RO metadata from sysfs */
        snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu.cpu, path);

        return perf_pmu__file_exists(pmu, pmu_path);
}

#define TRCDEVARCH_ARCHPART_SHIFT 0
#define TRCDEVARCH_ARCHPART_MASK  GENMASK(11, 0)
#define TRCDEVARCH_ARCHPART(x)    (((x) & TRCDEVARCH_ARCHPART_MASK) >> TRCDEVARCH_ARCHPART_SHIFT)

#define TRCDEVARCH_ARCHVER_SHIFT 12
#define TRCDEVARCH_ARCHVER_MASK  GENMASK(15, 12)
#define TRCDEVARCH_ARCHVER(x)    (((x) & TRCDEVARCH_ARCHVER_MASK) >> TRCDEVARCH_ARCHVER_SHIFT)

static bool cs_etm_is_ete(struct perf_pmu *cs_etm_pmu, struct perf_cpu cpu)
{
        __u64 trcdevarch;

        if (!cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH]))
                return false;

        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH], &trcdevarch);
        /*
         * ETE if ARCHVER is 5 (ARCHVER is 4 for ETM) and ARCHPART is 0xA13.
         * See ETM_DEVARCH_ETE_ARCH in coresight-etm4x.h
         */
        return TRCDEVARCH_ARCHVER(trcdevarch) == 5 && TRCDEVARCH_ARCHPART(trcdevarch) == 0xA13;
}

static __u64 cs_etm_get_legacy_trace_id(struct perf_cpu cpu)
{
        /* Wrap at 48 so that invalid trace IDs aren't saved into files. */
        return CORESIGHT_LEGACY_CPU_TRACE_ID(cpu.cpu % 48);
}

static void cs_etm_save_etmv4_header(__u64 data[], struct auxtrace_record *itr, struct perf_cpu cpu)
{
        struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);
        struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;

        /* Get trace configuration register */
        data[CS_ETMV4_TRCCONFIGR] = cs_etmv4_synth_trcconfigr(itr);
        /* traceID set to legacy version, in case new perf running on older system */
        data[CS_ETMV4_TRCTRACEIDR] = cs_etm_get_legacy_trace_id(cpu);

        /* Get read-only information from sysFS */
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0],
                      &data[CS_ETMV4_TRCIDR0]);
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR1],
                      &data[CS_ETMV4_TRCIDR1]);
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR2],
                      &data[CS_ETMV4_TRCIDR2]);
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR8],
                      &data[CS_ETMV4_TRCIDR8]);
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCAUTHSTATUS],
                      &data[CS_ETMV4_TRCAUTHSTATUS]);

        /* Kernels older than 5.19 may not expose ts_source */
        if (!cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TS_SOURCE]) ||
            cs_etm_get_ro_signed(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TS_SOURCE],
                                 &data[CS_ETMV4_TS_SOURCE])) {
                pr_debug3("[%03d] pmu file 'ts_source' not found. Fallback to safe value (-1)\n",
                          cpu.cpu);
                data[CS_ETMV4_TS_SOURCE] = (__u64) -1;
        }
}

static void cs_etm_save_ete_header(__u64 data[], struct auxtrace_record *itr, struct perf_cpu cpu)
{
        struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);
        struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;

        /* Get trace configuration register */
        data[CS_ETE_TRCCONFIGR] = cs_etmv4_synth_trcconfigr(itr);
        /* traceID set to legacy version, in case new perf running on older system */
        data[CS_ETE_TRCTRACEIDR] = cs_etm_get_legacy_trace_id(cpu);

        /* Get read-only information from sysFS */
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCIDR0], &data[CS_ETE_TRCIDR0]);
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCIDR1], &data[CS_ETE_TRCIDR1]);
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCIDR2], &data[CS_ETE_TRCIDR2]);
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCIDR8], &data[CS_ETE_TRCIDR8]);
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCAUTHSTATUS],
                      &data[CS_ETE_TRCAUTHSTATUS]);
        /* ETE uses the same registers as ETMv4 plus TRCDEVARCH */
        cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH],
                      &data[CS_ETE_TRCDEVARCH]);

        /* Kernels older than 5.19 may not expose ts_source */
        if (!cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TS_SOURCE]) ||
            cs_etm_get_ro_signed(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TS_SOURCE],
                                 &data[CS_ETE_TS_SOURCE])) {
                pr_debug3("[%03d] pmu file 'ts_source' not found. Fallback to safe value (-1)\n",
                          cpu.cpu);
                data[CS_ETE_TS_SOURCE] = (__u64) -1;
        }
}

static void cs_etm_get_metadata(struct perf_cpu cpu, u32 *offset,
                                struct auxtrace_record *itr,
                                struct perf_record_auxtrace_info *info)
{
        u32 increment, nr_trc_params;
        u64 magic;
        struct perf_pmu *cs_etm_pmu = cs_etm_get_pmu(itr);

        /* first see what kind of tracer this cpu is affined to */
        switch (cs_etm_get_version(cs_etm_pmu, cpu)) {
        case CS_ETE:
                magic = __perf_cs_ete_magic;
                cs_etm_save_ete_header(&info->priv[*offset], itr, cpu);

                /* How much space was used */
                increment = CS_ETE_PRIV_MAX;
                nr_trc_params = CS_ETE_PRIV_MAX - CS_ETM_COMMON_BLK_MAX_V1;
                break;

        case CS_ETMV4:
                magic = __perf_cs_etmv4_magic;
                cs_etm_save_etmv4_header(&info->priv[*offset], itr, cpu);

                /* How much space was used */
                increment = CS_ETMV4_PRIV_MAX;
                nr_trc_params = CS_ETMV4_PRIV_MAX - CS_ETMV4_TRCCONFIGR;
                break;

        case CS_ETMV3:
                magic = __perf_cs_etmv3_magic;
                /* Get configuration register */
                info->priv[*offset + CS_ETM_ETMCR] = cs_etm_synth_etmcr(itr);
                /* traceID set to legacy value in case new perf running on old system */
                info->priv[*offset + CS_ETM_ETMTRACEIDR] = cs_etm_get_legacy_trace_id(cpu);
                /* Get read-only information from sysFS */
                cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv3_ro[CS_ETM_ETMCCER],
                              &info->priv[*offset + CS_ETM_ETMCCER]);
                cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv3_ro[CS_ETM_ETMIDR],
                              &info->priv[*offset + CS_ETM_ETMIDR]);

                /* How much space was used */
                increment = CS_ETM_PRIV_MAX;
                nr_trc_params = CS_ETM_PRIV_MAX - CS_ETM_ETMCR;
                break;

        default:
        case CS_NOT_PRESENT:
                /* Unreachable, CPUs already validated in cs_etm_validate_config() */
                assert(true);
                return;
        }

        /* Build generic header portion */
        info->priv[*offset + CS_ETM_MAGIC] = magic;
        info->priv[*offset + CS_ETM_CPU] = cpu.cpu;
        info->priv[*offset + CS_ETM_NR_TRC_PARAMS] = nr_trc_params;
        /* Where the next CPU entry should start from */
        *offset += increment;
}

static int cs_etm_info_fill(struct auxtrace_record *itr,
                            struct perf_session *session,
                            struct perf_record_auxtrace_info *info,
                            size_t priv_size)
{
        int i;
        u32 offset;
        u64 nr_cpu, type;
        struct perf_cpu_map *cpu_map;
        struct perf_cpu_map *event_cpus = session->evlist->core.user_requested_cpus;
        struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();
        struct cs_etm_recording *ptr =
                        container_of(itr, struct cs_etm_recording, itr);
        struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
        struct perf_cpu cpu;

        if (priv_size != cs_etm_info_priv_size(itr, session->evlist))
                return -EINVAL;

        if (!session->evlist->core.nr_mmaps)
                return -EINVAL;

        /* If the cpu_map has the "any" CPU all online CPUs are involved */
        if (perf_cpu_map__has_any_cpu(event_cpus)) {
                cpu_map = online_cpus;
        } else {
                /* Make sure all specified CPUs are online */
                perf_cpu_map__for_each_cpu(cpu, i, event_cpus) {
                        if (!perf_cpu_map__has(online_cpus, cpu))
                                return -EINVAL;
                }

                cpu_map = event_cpus;
        }

        nr_cpu = perf_cpu_map__nr(cpu_map);
        /* Get PMU type as dynamically assigned by the core */
        type = cs_etm_pmu->type;

        /* First fill out the session header */
        info->type = PERF_AUXTRACE_CS_ETM;
        info->priv[CS_HEADER_VERSION] = CS_HEADER_CURRENT_VERSION;
        info->priv[CS_PMU_TYPE_CPUS] = type << 32;
        info->priv[CS_PMU_TYPE_CPUS] |= nr_cpu;
        info->priv[CS_ETM_SNAPSHOT] = ptr->snapshot_mode;

        offset = CS_ETM_SNAPSHOT + 1;

        perf_cpu_map__for_each_cpu(cpu, i, cpu_map) {
                assert(offset < priv_size);
                cs_etm_get_metadata(cpu, &offset, itr, info);
        }

        perf_cpu_map__put(online_cpus);

        return 0;
}

static int cs_etm_snapshot_start(struct auxtrace_record *itr)
{
        struct cs_etm_recording *ptr =
                        container_of(itr, struct cs_etm_recording, itr);
        struct evsel *evsel = cs_etm_get_evsel(ptr->evlist, ptr->cs_etm_pmu);

        if (evsel)
                return evsel__disable(evsel);

        return -EINVAL;
}

static int cs_etm_snapshot_finish(struct auxtrace_record *itr)
{
        struct cs_etm_recording *ptr =
                        container_of(itr, struct cs_etm_recording, itr);
        struct evsel *evsel;

        evlist__for_each_entry(ptr->evlist, evsel) {
                if (evsel->core.attr.type == ptr->cs_etm_pmu->type)
                        return evsel__enable(evsel);
        }
        return -EINVAL;
}

static u64 cs_etm_reference(struct auxtrace_record *itr __maybe_unused)
{
        return (((u64) rand() <<  0) & 0x00000000FFFFFFFFull) |
                (((u64) rand() << 32) & 0xFFFFFFFF00000000ull);
}

static void cs_etm_recording_free(struct auxtrace_record *itr)
{
        struct cs_etm_recording *ptr =
                        container_of(itr, struct cs_etm_recording, itr);

        free(ptr);
}

struct auxtrace_record *cs_etm_record_init(int *err)
{
        struct perf_pmu *cs_etm_pmu;
        struct cs_etm_recording *ptr;

        cs_etm_pmu = perf_pmus__find(CORESIGHT_ETM_PMU_NAME);

        if (!cs_etm_pmu) {
                *err = -EINVAL;
                goto out;
        }

        ptr = zalloc(sizeof(struct cs_etm_recording));
        if (!ptr) {
                *err = -ENOMEM;
                goto out;
        }

        ptr->cs_etm_pmu                 = cs_etm_pmu;
        ptr->itr.parse_snapshot_options = cs_etm_parse_snapshot_options;
        ptr->itr.recording_options      = cs_etm_recording_options;
        ptr->itr.info_priv_size         = cs_etm_info_priv_size;
        ptr->itr.info_fill              = cs_etm_info_fill;
        ptr->itr.snapshot_start         = cs_etm_snapshot_start;
        ptr->itr.snapshot_finish        = cs_etm_snapshot_finish;
        ptr->itr.reference              = cs_etm_reference;
        ptr->itr.free                   = cs_etm_recording_free;
        ptr->itr.read_finish            = auxtrace_record__read_finish;

        *err = 0;
        return &ptr->itr;
out:
        return NULL;
}

/*
 * Set a default config to enable the user changed config tracking mechanism
 * (CFG_CHG and evsel__set_config_if_unset()). If no default is set then user
 * changes aren't tracked.
 */
void
cs_etm_get_default_config(const struct perf_pmu *pmu __maybe_unused,
                          struct perf_event_attr *attr)
{
        attr->sample_period = 1;
}