// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright IBM Corp. 2019
 * Author(s): Thomas Richter <tmricht@linux.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License (version 2 only)
 * as published by the Free Software Foundation.
 *
 * Architecture specific trace_event function. Save event's bc000 raw data
 * to file. File name is aux.ctr.## where ## stands for the CPU number the
 * sample was taken from.
 */

#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <inttypes.h>

#include <sys/stat.h>
#include <linux/compiler.h>
#include <asm/byteorder.h>

#include "debug.h"
#include "session.h"
#include "evlist.h"
#include "color.h"
#include "sample-raw.h"
#include "s390-cpumcf-kernel.h"
#include "pmu-events/pmu-events.h"

static size_t ctrset_size(struct cf_ctrset_entry *set)
{
        return sizeof(*set) + set->ctr * sizeof(u64);
}

static bool ctrset_valid(struct cf_ctrset_entry *set)
{
        return set->def == S390_CPUMCF_DIAG_DEF;
}

/* CPU Measurement Counter Facility raw data is a byte stream. It is 8 byte
 * aligned and might have trailing padding bytes.
 * Display the raw data on screen.
 */
static bool s390_cpumcfdg_testctr(struct perf_sample *sample)
{
        size_t len = sample->raw_size, offset = 0;
        unsigned char *buf = sample->raw_data;
        struct cf_trailer_entry *te;
        struct cf_ctrset_entry *cep, ce;

        if (!len)
                return false;
        while (offset < len) {
                cep = (struct cf_ctrset_entry *)(buf + offset);
                ce.def = be16_to_cpu(cep->def);
                ce.set = be16_to_cpu(cep->set);
                ce.ctr = be16_to_cpu(cep->ctr);
                ce.res1 = be16_to_cpu(cep->res1);

                if (!ctrset_valid(&ce) || offset + ctrset_size(&ce) > len) {
                        /* Raw data for counter sets are always multiple of 8
                         * bytes. Prepending a 4 bytes size field to the
                         * raw data block in the sample causes the perf tool
                         * to append 4 padding bytes to make the raw data part
                         * of the sample a multiple of eight bytes again.
                         *
                         * If the last entry (trailer) is 4 bytes off the raw
                         * area data end, all is good.
                         */
                        if (len - offset - sizeof(*te) == 4)
                                break;
                        pr_err("Invalid counter set entry at %zd\n", offset);
                        return false;
                }
                offset += ctrset_size(&ce);
        }
        return true;
}

/* Dump event bc000 on screen, already tested on correctness. */
static void s390_cpumcfdg_dumptrail(const char *color, size_t offset,
                                    struct cf_trailer_entry *tep)
{
        struct cf_trailer_entry  te;

        te.flags = be64_to_cpu(tep->flags);
        te.cfvn = be16_to_cpu(tep->cfvn);
        te.csvn = be16_to_cpu(tep->csvn);
        te.cpu_speed = be32_to_cpu(tep->cpu_speed);
        te.timestamp = be64_to_cpu(tep->timestamp);
        te.progusage1 = be64_to_cpu(tep->progusage1);
        te.progusage2 = be64_to_cpu(tep->progusage2);
        te.progusage3 = be64_to_cpu(tep->progusage3);
        te.tod_base = be64_to_cpu(tep->tod_base);
        te.mach_type = be16_to_cpu(tep->mach_type);
        te.res1 = be16_to_cpu(tep->res1);
        te.res2 = be32_to_cpu(tep->res2);

        color_fprintf(stdout, color, "    [%#08zx] Trailer:%c%c%c%c%c"
                      " Cfvn:%d Csvn:%d Speed:%d TOD:%#llx\n",
                      offset, te.clock_base ? 'T' : ' ',
                      te.speed ? 'S' : ' ', te.mtda ? 'M' : ' ',
                      te.caca ? 'C' : ' ', te.lcda ? 'L' : ' ',
                      te.cfvn, te.csvn, te.cpu_speed, te.timestamp);
        color_fprintf(stdout, color, "\t\t1:%lx 2:%lx 3:%lx TOD-Base:%#llx"
                      " Type:%x\n\n",
                      te.progusage1, te.progusage2, te.progusage3,
                      te.tod_base, te.mach_type);
}

/* Return starting number of a counter set */
static int get_counterset_start(int setnr)
{
        switch (setnr) {
        case CPUMF_CTR_SET_BASIC:               /* Basic counter set */
                return 0;
        case CPUMF_CTR_SET_USER:                /* Problem state counter set */
                return 32;
        case CPUMF_CTR_SET_CRYPTO:              /* Crypto counter set */
                return 64;
        case CPUMF_CTR_SET_EXT:                 /* Extended counter set */
                return 128;
        case CPUMF_CTR_SET_MT_DIAG:             /* Diagnostic counter set */
                return 448;
        default:
                return -1;
        }
}

/* Scan the PMU table and extract the logical name of a counter from the
 * PMU events table. Input is the counter set and counter number with in the
 * set. Construct the event number and use this as key. If they match return
 * the name of this counter.
 * If no match is found a NULL pointer is returned.
 */
static const char *get_counter_name(int set, int nr, struct pmu_events_map *map)
{
        int rc, event_nr, wanted = get_counterset_start(set) + nr;

        if (map) {
                struct pmu_event *evp = map->table;

                for (; evp->name || evp->event || evp->desc; ++evp) {
                        if (evp->name == NULL || evp->event == NULL)
                                continue;
                        rc = sscanf(evp->event, "event=%x", &event_nr);
                        if (rc == 1 && event_nr == wanted)
                                return evp->name;
                }
        }
        return NULL;
}

static void s390_cpumcfdg_dump(struct perf_sample *sample)
{
        size_t i, len = sample->raw_size, offset = 0;
        unsigned char *buf = sample->raw_data;
        const char *color = PERF_COLOR_BLUE;
        struct cf_ctrset_entry *cep, ce;
        struct pmu_events_map *map;
        struct perf_pmu pmu;
        u64 *p;

        memset(&pmu, 0, sizeof(pmu));
        map = perf_pmu__find_map(&pmu);
        while (offset < len) {
                cep = (struct cf_ctrset_entry *)(buf + offset);

                ce.def = be16_to_cpu(cep->def);
                ce.set = be16_to_cpu(cep->set);
                ce.ctr = be16_to_cpu(cep->ctr);
                ce.res1 = be16_to_cpu(cep->res1);

                if (!ctrset_valid(&ce)) {       /* Print trailer */
                        s390_cpumcfdg_dumptrail(color, offset,
                                                (struct cf_trailer_entry *)cep);
                        return;
                }

                color_fprintf(stdout, color, "    [%#08zx] Counterset:%d"
                              " Counters:%d\n", offset, ce.set, ce.ctr);
                for (i = 0, p = (u64 *)(cep + 1); i < ce.ctr; ++i, ++p) {
                        const char *ev_name = get_counter_name(ce.set, i, map);

                        color_fprintf(stdout, color,
                                      "\tCounter:%03d %s Value:%#018lx\n", i,
                                      ev_name ?: "<unknown>", be64_to_cpu(*p));
                }
                offset += ctrset_size(&ce);
        }
}

/* S390 specific trace event function. Check for PERF_RECORD_SAMPLE events
 * and if the event was triggered by a counter set diagnostic event display
 * its raw data.
 * The function is only invoked when the dump flag -D is set.
 */
void perf_evlist__s390_sample_raw(struct evlist *evlist, union perf_event *event,
                                  struct perf_sample *sample)
{
        struct evsel *ev_bc000;

        if (event->header.type != PERF_RECORD_SAMPLE)
                return;

        ev_bc000 = perf_evlist__event2evsel(evlist, event);
        if (ev_bc000 == NULL ||
            ev_bc000->core.attr.config != PERF_EVENT_CPUM_CF_DIAG)
                return;

        /* Display raw data on screen */
        if (!s390_cpumcfdg_testctr(sample)) {
                pr_err("Invalid counter set data encountered\n");
                return;
        }
        s390_cpumcfdg_dump(sample);
}