// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright(C) 2015-2018 Linaro Limited.
 *
 * Author: Tor Jeremiassen <tor@ti.com>
 * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
 */

#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/log2.h>
#include <linux/types.h>

#include <stdlib.h>

#include "auxtrace.h"
#include "color.h"
#include "cs-etm.h"
#include "cs-etm-decoder/cs-etm-decoder.h"
#include "debug.h"
#include "evlist.h"
#include "intlist.h"
#include "machine.h"
#include "map.h"
#include "perf.h"
#include "thread.h"
#include "thread_map.h"
#include "thread-stack.h"
#include "util.h"

#define MAX_TIMESTAMP (~0ULL)

/*
 * A64 instructions are always 4 bytes
 *
 * Only A64 is supported, so can use this constant for converting between
 * addresses and instruction counts, calculting offsets etc
 */
#define A64_INSTR_SIZE 4

struct cs_etm_auxtrace {
        struct auxtrace auxtrace;
        struct auxtrace_queues queues;
        struct auxtrace_heap heap;
        struct itrace_synth_opts synth_opts;
        struct perf_session *session;
        struct machine *machine;
        struct thread *unknown_thread;

        u8 timeless_decoding;
        u8 snapshot_mode;
        u8 data_queued;
        u8 sample_branches;
        u8 sample_instructions;

        int num_cpu;
        u32 auxtrace_type;
        u64 branches_sample_type;
        u64 branches_id;
        u64 instructions_sample_type;
        u64 instructions_sample_period;
        u64 instructions_id;
        u64 **metadata;
        u64 kernel_start;
        unsigned int pmu_type;
};

struct cs_etm_queue {
        struct cs_etm_auxtrace *etm;
        struct thread *thread;
        struct cs_etm_decoder *decoder;
        struct auxtrace_buffer *buffer;
        const struct cs_etm_state *state;
        union perf_event *event_buf;
        unsigned int queue_nr;
        pid_t pid, tid;
        int cpu;
        u64 time;
        u64 timestamp;
        u64 offset;
        u64 period_instructions;
        struct branch_stack *last_branch;
        struct branch_stack *last_branch_rb;
        size_t last_branch_pos;
        struct cs_etm_packet *prev_packet;
        struct cs_etm_packet *packet;
};

static int cs_etm__update_queues(struct cs_etm_auxtrace *etm);
static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
                                           pid_t tid, u64 time_);

static void cs_etm__packet_dump(const char *pkt_string)
{
        const char *color = PERF_COLOR_BLUE;
        int len = strlen(pkt_string);

        if (len && (pkt_string[len-1] == '\n'))
                color_fprintf(stdout, color, "  %s", pkt_string);
        else
                color_fprintf(stdout, color, "  %s\n", pkt_string);

        fflush(stdout);
}

static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
                               struct auxtrace_buffer *buffer)
{
        int i, ret;
        const char *color = PERF_COLOR_BLUE;
        struct cs_etm_decoder_params d_params;
        struct cs_etm_trace_params *t_params;
        struct cs_etm_decoder *decoder;
        size_t buffer_used = 0;

        fprintf(stdout, "\n");
        color_fprintf(stdout, color,
                     ". ... CoreSight ETM Trace data: size %zu bytes\n",
                     buffer->size);

        /* Use metadata to fill in trace parameters for trace decoder */
        t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
        for (i = 0; i < etm->num_cpu; i++) {
                t_params[i].protocol = CS_ETM_PROTO_ETMV4i;
                t_params[i].etmv4.reg_idr0 = etm->metadata[i][CS_ETMV4_TRCIDR0];
                t_params[i].etmv4.reg_idr1 = etm->metadata[i][CS_ETMV4_TRCIDR1];
                t_params[i].etmv4.reg_idr2 = etm->metadata[i][CS_ETMV4_TRCIDR2];
                t_params[i].etmv4.reg_idr8 = etm->metadata[i][CS_ETMV4_TRCIDR8];
                t_params[i].etmv4.reg_configr =
                                        etm->metadata[i][CS_ETMV4_TRCCONFIGR];
                t_params[i].etmv4.reg_traceidr =
                                        etm->metadata[i][CS_ETMV4_TRCTRACEIDR];
        }

        /* Set decoder parameters to simply print the trace packets */
        d_params.packet_printer = cs_etm__packet_dump;
        d_params.operation = CS_ETM_OPERATION_PRINT;
        d_params.formatted = true;
        d_params.fsyncs = false;
        d_params.hsyncs = false;
        d_params.frame_aligned = true;

        decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);

        zfree(&t_params);

        if (!decoder)
                return;
        do {
                size_t consumed;

                ret = cs_etm_decoder__process_data_block(
                                decoder, buffer->offset,
                                &((u8 *)buffer->data)[buffer_used],
                                buffer->size - buffer_used, &consumed);
                if (ret)
                        break;

                buffer_used += consumed;
        } while (buffer_used < buffer->size);

        cs_etm_decoder__free(decoder);
}

static int cs_etm__flush_events(struct perf_session *session,
                                struct perf_tool *tool)
{
        int ret;
        struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
                                                   struct cs_etm_auxtrace,
                                                   auxtrace);
        if (dump_trace)
                return 0;

        if (!tool->ordered_events)
                return -EINVAL;

        if (!etm->timeless_decoding)
                return -EINVAL;

        ret = cs_etm__update_queues(etm);

        if (ret < 0)
                return ret;

        return cs_etm__process_timeless_queues(etm, -1, MAX_TIMESTAMP - 1);
}

static void cs_etm__free_queue(void *priv)
{
        struct cs_etm_queue *etmq = priv;

        if (!etmq)
                return;

        thread__zput(etmq->thread);
        cs_etm_decoder__free(etmq->decoder);
        zfree(&etmq->event_buf);
        zfree(&etmq->last_branch);
        zfree(&etmq->last_branch_rb);
        zfree(&etmq->prev_packet);
        zfree(&etmq->packet);
        free(etmq);
}

static void cs_etm__free_events(struct perf_session *session)
{
        unsigned int i;
        struct cs_etm_auxtrace *aux = container_of(session->auxtrace,
                                                   struct cs_etm_auxtrace,
                                                   auxtrace);
        struct auxtrace_queues *queues = &aux->queues;

        for (i = 0; i < queues->nr_queues; i++) {
                cs_etm__free_queue(queues->queue_array[i].priv);
                queues->queue_array[i].priv = NULL;
        }

        auxtrace_queues__free(queues);
}

static void cs_etm__free(struct perf_session *session)
{
        int i;
        struct int_node *inode, *tmp;
        struct cs_etm_auxtrace *aux = container_of(session->auxtrace,
                                                   struct cs_etm_auxtrace,
                                                   auxtrace);
        cs_etm__free_events(session);
        session->auxtrace = NULL;

        /* First remove all traceID/CPU# nodes for the RB tree */
        intlist__for_each_entry_safe(inode, tmp, traceid_list)
                intlist__remove(traceid_list, inode);
        /* Then the RB tree itself */
        intlist__delete(traceid_list);

        for (i = 0; i < aux->num_cpu; i++)
                zfree(&aux->metadata[i]);

        thread__zput(aux->unknown_thread);
        zfree(&aux->metadata);
        zfree(&aux);
}

static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u64 address,
                              size_t size, u8 *buffer)
{
        u8  cpumode;
        u64 offset;
        int len;
        struct   thread *thread;
        struct   machine *machine;
        struct   addr_location al;

        if (!etmq)
                return -1;

        machine = etmq->etm->machine;
        if (address >= etmq->etm->kernel_start)
                cpumode = PERF_RECORD_MISC_KERNEL;
        else
                cpumode = PERF_RECORD_MISC_USER;

        thread = etmq->thread;
        if (!thread) {
                if (cpumode != PERF_RECORD_MISC_KERNEL)
                        return -EINVAL;
                thread = etmq->etm->unknown_thread;
        }

        if (!thread__find_map(thread, cpumode, address, &al) || !al.map->dso)
                return 0;

        if (al.map->dso->data.status == DSO_DATA_STATUS_ERROR &&
            dso__data_status_seen(al.map->dso, DSO_DATA_STATUS_SEEN_ITRACE))
                return 0;

        offset = al.map->map_ip(al.map, address);

        map__load(al.map);

        len = dso__data_read_offset(al.map->dso, machine, offset, buffer, size);

        if (len <= 0)
                return 0;

        return len;
}

static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm,
                                                unsigned int queue_nr)
{
        int i;
        struct cs_etm_decoder_params d_params;
        struct cs_etm_trace_params  *t_params;
        struct cs_etm_queue *etmq;
        size_t szp = sizeof(struct cs_etm_packet);

        etmq = zalloc(sizeof(*etmq));
        if (!etmq)
                return NULL;

        etmq->packet = zalloc(szp);
        if (!etmq->packet)
                goto out_free;

        if (etm->synth_opts.last_branch || etm->sample_branches) {
                etmq->prev_packet = zalloc(szp);
                if (!etmq->prev_packet)
                        goto out_free;
        }

        if (etm->synth_opts.last_branch) {
                size_t sz = sizeof(struct branch_stack);

                sz += etm->synth_opts.last_branch_sz *
                      sizeof(struct branch_entry);
                etmq->last_branch = zalloc(sz);
                if (!etmq->last_branch)
                        goto out_free;
                etmq->last_branch_rb = zalloc(sz);
                if (!etmq->last_branch_rb)
                        goto out_free;
        }

        etmq->event_buf = malloc(PERF_SAMPLE_MAX_SIZE);
        if (!etmq->event_buf)
                goto out_free;

        etmq->etm = etm;
        etmq->queue_nr = queue_nr;
        etmq->pid = -1;
        etmq->tid = -1;
        etmq->cpu = -1;

        /* Use metadata to fill in trace parameters for trace decoder */
        t_params = zalloc(sizeof(*t_params) * etm->num_cpu);

        if (!t_params)
                goto out_free;

        for (i = 0; i < etm->num_cpu; i++) {
                t_params[i].protocol = CS_ETM_PROTO_ETMV4i;
                t_params[i].etmv4.reg_idr0 = etm->metadata[i][CS_ETMV4_TRCIDR0];
                t_params[i].etmv4.reg_idr1 = etm->metadata[i][CS_ETMV4_TRCIDR1];
                t_params[i].etmv4.reg_idr2 = etm->metadata[i][CS_ETMV4_TRCIDR2];
                t_params[i].etmv4.reg_idr8 = etm->metadata[i][CS_ETMV4_TRCIDR8];
                t_params[i].etmv4.reg_configr =
                                        etm->metadata[i][CS_ETMV4_TRCCONFIGR];
                t_params[i].etmv4.reg_traceidr =
                                        etm->metadata[i][CS_ETMV4_TRCTRACEIDR];
        }

        /* Set decoder parameters to simply print the trace packets */
        d_params.packet_printer = cs_etm__packet_dump;
        d_params.operation = CS_ETM_OPERATION_DECODE;
        d_params.formatted = true;
        d_params.fsyncs = false;
        d_params.hsyncs = false;
        d_params.frame_aligned = true;
        d_params.data = etmq;

        etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);

        zfree(&t_params);

        if (!etmq->decoder)
                goto out_free;

        /*
         * Register a function to handle all memory accesses required by
         * the trace decoder library.
         */
        if (cs_etm_decoder__add_mem_access_cb(etmq->decoder,
                                              0x0L, ((u64) -1L),
                                              cs_etm__mem_access))
                goto out_free_decoder;

        etmq->offset = 0;
        etmq->period_instructions = 0;

        return etmq;

out_free_decoder:
        cs_etm_decoder__free(etmq->decoder);
out_free:
        zfree(&etmq->event_buf);
        zfree(&etmq->last_branch);
        zfree(&etmq->last_branch_rb);
        zfree(&etmq->prev_packet);
        zfree(&etmq->packet);
        free(etmq);

        return NULL;
}

static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
                               struct auxtrace_queue *queue,
                               unsigned int queue_nr)
{
        struct cs_etm_queue *etmq = queue->priv;

        if (list_empty(&queue->head) || etmq)
                return 0;

        etmq = cs_etm__alloc_queue(etm, queue_nr);

        if (!etmq)
                return -ENOMEM;

        queue->priv = etmq;

        if (queue->cpu != -1)
                etmq->cpu = queue->cpu;

        etmq->tid = queue->tid;

        return 0;
}

static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
{
        unsigned int i;
        int ret;

        for (i = 0; i < etm->queues.nr_queues; i++) {
                ret = cs_etm__setup_queue(etm, &etm->queues.queue_array[i], i);
                if (ret)
                        return ret;
        }

        return 0;
}

static int cs_etm__update_queues(struct cs_etm_auxtrace *etm)
{
        if (etm->queues.new_data) {
                etm->queues.new_data = false;
                return cs_etm__setup_queues(etm);
        }

        return 0;
}

static inline void cs_etm__copy_last_branch_rb(struct cs_etm_queue *etmq)
{
        struct branch_stack *bs_src = etmq->last_branch_rb;
        struct branch_stack *bs_dst = etmq->last_branch;
        size_t nr = 0;

        /*
         * Set the number of records before early exit: ->nr is used to
         * determine how many branches to copy from ->entries.
         */
        bs_dst->nr = bs_src->nr;

        /*
         * Early exit when there is nothing to copy.
         */
        if (!bs_src->nr)
                return;

        /*
         * As bs_src->entries is a circular buffer, we need to copy from it in
         * two steps.  First, copy the branches from the most recently inserted
         * branch ->last_branch_pos until the end of bs_src->entries buffer.
         */
        nr = etmq->etm->synth_opts.last_branch_sz - etmq->last_branch_pos;
        memcpy(&bs_dst->entries[0],
               &bs_src->entries[etmq->last_branch_pos],
               sizeof(struct branch_entry) * nr);

        /*
         * If we wrapped around at least once, the branches from the beginning
         * of the bs_src->entries buffer and until the ->last_branch_pos element
         * are older valid branches: copy them over.  The total number of
         * branches copied over will be equal to the number of branches asked by
         * the user in last_branch_sz.
         */
        if (bs_src->nr >= etmq->etm->synth_opts.last_branch_sz) {
                memcpy(&bs_dst->entries[nr],
                       &bs_src->entries[0],
                       sizeof(struct branch_entry) * etmq->last_branch_pos);
        }
}

static inline void cs_etm__reset_last_branch_rb(struct cs_etm_queue *etmq)
{
        etmq->last_branch_pos = 0;
        etmq->last_branch_rb->nr = 0;
}

static inline u64 cs_etm__last_executed_instr(struct cs_etm_packet *packet)
{
        /* Returns 0 for the CS_ETM_TRACE_ON packet */
        if (packet->sample_type == CS_ETM_TRACE_ON)
                return 0;

        /*
         * The packet records the execution range with an exclusive end address
         *
         * A64 instructions are constant size, so the last executed
         * instruction is A64_INSTR_SIZE before the end address
         * Will need to do instruction level decode for T32 instructions as
         * they can be variable size (not yet supported).
         */
        return packet->end_addr - A64_INSTR_SIZE;
}

static inline u64 cs_etm__first_executed_instr(struct cs_etm_packet *packet)
{
        /* Returns 0 for the CS_ETM_TRACE_ON packet */
        if (packet->sample_type == CS_ETM_TRACE_ON)
                return 0;

        return packet->start_addr;
}

static inline u64 cs_etm__instr_count(const struct cs_etm_packet *packet)
{
        /*
         * Only A64 instructions are currently supported, so can get
         * instruction count by dividing.
         * Will need to do instruction level decode for T32 instructions as
         * they can be variable size (not yet supported).
         */
        return (packet->end_addr - packet->start_addr) / A64_INSTR_SIZE;
}

static inline u64 cs_etm__instr_addr(const struct cs_etm_packet *packet,
                                     u64 offset)
{
        /*
         * Only A64 instructions are currently supported, so can get
         * instruction address by muliplying.
         * Will need to do instruction level decode for T32 instructions as
         * they can be variable size (not yet supported).
         */
        return packet->start_addr + offset * A64_INSTR_SIZE;
}

static void cs_etm__update_last_branch_rb(struct cs_etm_queue *etmq)
{
        struct branch_stack *bs = etmq->last_branch_rb;
        struct branch_entry *be;

        /*
         * The branches are recorded in a circular buffer in reverse
         * chronological order: we start recording from the last element of the
         * buffer down.  After writing the first element of the stack, move the
         * insert position back to the end of the buffer.
         */
        if (!etmq->last_branch_pos)
                etmq->last_branch_pos = etmq->etm->synth_opts.last_branch_sz;

        etmq->last_branch_pos -= 1;

        be       = &bs->entries[etmq->last_branch_pos];
        be->from = cs_etm__last_executed_instr(etmq->prev_packet);
        be->to   = cs_etm__first_executed_instr(etmq->packet);
        /* No support for mispredict */
        be->flags.mispred = 0;
        be->flags.predicted = 1;

        /*
         * Increment bs->nr until reaching the number of last branches asked by
         * the user on the command line.
         */
        if (bs->nr < etmq->etm->synth_opts.last_branch_sz)
                bs->nr += 1;
}

static int cs_etm__inject_event(union perf_event *event,
                               struct perf_sample *sample, u64 type)
{
        event->header.size = perf_event__sample_event_size(sample, type, 0);
        return perf_event__synthesize_sample(event, type, 0, sample);
}


static int
cs_etm__get_trace(struct cs_etm_buffer *buff, struct cs_etm_queue *etmq)
{
        struct auxtrace_buffer *aux_buffer = etmq->buffer;
        struct auxtrace_buffer *old_buffer = aux_buffer;
        struct auxtrace_queue *queue;

        queue = &etmq->etm->queues.queue_array[etmq->queue_nr];

        aux_buffer = auxtrace_buffer__next(queue, aux_buffer);

        /* If no more data, drop the previous auxtrace_buffer and return */
        if (!aux_buffer) {
                if (old_buffer)
                        auxtrace_buffer__drop_data(old_buffer);
                buff->len = 0;
                return 0;
        }

        etmq->buffer = aux_buffer;

        /* If the aux_buffer doesn't have data associated, try to load it */
        if (!aux_buffer->data) {
                /* get the file desc associated with the perf data file */
                int fd = perf_data__fd(etmq->etm->session->data);

                aux_buffer->data = auxtrace_buffer__get_data(aux_buffer, fd);
                if (!aux_buffer->data)
                        return -ENOMEM;
        }

        /* If valid, drop the previous buffer */
        if (old_buffer)
                auxtrace_buffer__drop_data(old_buffer);

        buff->offset = aux_buffer->offset;
        buff->len = aux_buffer->size;
        buff->buf = aux_buffer->data;

        buff->ref_timestamp = aux_buffer->reference;

        return buff->len;
}

static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
                                    struct auxtrace_queue *queue)
{
        struct cs_etm_queue *etmq = queue->priv;

        /* CPU-wide tracing isn't supported yet */
        if (queue->tid == -1)
                return;

        if ((!etmq->thread) && (etmq->tid != -1))
                etmq->thread = machine__find_thread(etm->machine, -1,
                                                    etmq->tid);

        if (etmq->thread) {
                etmq->pid = etmq->thread->pid_;
                if (queue->cpu == -1)
                        etmq->cpu = etmq->thread->cpu;
        }
}

static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
                                            u64 addr, u64 period)
{
        int ret = 0;
        struct cs_etm_auxtrace *etm = etmq->etm;
        union perf_event *event = etmq->event_buf;
        struct perf_sample sample = {.ip = 0,};

        event->sample.header.type = PERF_RECORD_SAMPLE;
        event->sample.header.misc = PERF_RECORD_MISC_USER;
        event->sample.header.size = sizeof(struct perf_event_header);

        sample.ip = addr;
        sample.pid = etmq->pid;
        sample.tid = etmq->tid;
        sample.id = etmq->etm->instructions_id;
        sample.stream_id = etmq->etm->instructions_id;
        sample.period = period;
        sample.cpu = etmq->packet->cpu;
        sample.flags = 0;
        sample.insn_len = 1;
        sample.cpumode = event->header.misc;

        if (etm->synth_opts.last_branch) {
                cs_etm__copy_last_branch_rb(etmq);
                sample.branch_stack = etmq->last_branch;
        }

        if (etm->synth_opts.inject) {
                ret = cs_etm__inject_event(event, &sample,
                                           etm->instructions_sample_type);
                if (ret)
                        return ret;
        }

        ret = perf_session__deliver_synth_event(etm->session, event, &sample);

        if (ret)
                pr_err(
                        "CS ETM Trace: failed to deliver instruction event, error %d\n",
                        ret);

        if (etm->synth_opts.last_branch)
                cs_etm__reset_last_branch_rb(etmq);

        return ret;
}

/*
 * The cs etm packet encodes an instruction range between a branch target
 * and the next taken branch. Generate sample accordingly.
 */
static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq)
{
        int ret = 0;
        struct cs_etm_auxtrace *etm = etmq->etm;
        struct perf_sample sample = {.ip = 0,};
        union perf_event *event = etmq->event_buf;
        struct dummy_branch_stack {
                u64                     nr;
                struct branch_entry     entries;
        } dummy_bs;

        event->sample.header.type = PERF_RECORD_SAMPLE;
        event->sample.header.misc = PERF_RECORD_MISC_USER;
        event->sample.header.size = sizeof(struct perf_event_header);

        sample.ip = cs_etm__last_executed_instr(etmq->prev_packet);
        sample.pid = etmq->pid;
        sample.tid = etmq->tid;
        sample.addr = cs_etm__first_executed_instr(etmq->packet);
        sample.id = etmq->etm->branches_id;
        sample.stream_id = etmq->etm->branches_id;
        sample.period = 1;
        sample.cpu = etmq->packet->cpu;
        sample.flags = 0;
        sample.cpumode = PERF_RECORD_MISC_USER;

        /*
         * perf report cannot handle events without a branch stack
         */
        if (etm->synth_opts.last_branch) {
                dummy_bs = (struct dummy_branch_stack){
                        .nr = 1,
                        .entries = {
                                .from = sample.ip,
                                .to = sample.addr,
                        },
                };
                sample.branch_stack = (struct branch_stack *)&dummy_bs;
        }

        if (etm->synth_opts.inject) {
                ret = cs_etm__inject_event(event, &sample,
                                           etm->branches_sample_type);
                if (ret)
                        return ret;
        }

        ret = perf_session__deliver_synth_event(etm->session, event, &sample);

        if (ret)
                pr_err(
                "CS ETM Trace: failed to deliver instruction event, error %d\n",
                ret);

        return ret;
}

struct cs_etm_synth {
        struct perf_tool dummy_tool;
        struct perf_session *session;
};

static int cs_etm__event_synth(struct perf_tool *tool,
                               union perf_event *event,
                               struct perf_sample *sample __maybe_unused,
                               struct machine *machine __maybe_unused)
{
        struct cs_etm_synth *cs_etm_synth =
                      container_of(tool, struct cs_etm_synth, dummy_tool);

        return perf_session__deliver_synth_event(cs_etm_synth->session,
                                                 event, NULL);
}

static int cs_etm__synth_event(struct perf_session *session,
                               struct perf_event_attr *attr, u64 id)
{
        struct cs_etm_synth cs_etm_synth;

        memset(&cs_etm_synth, 0, sizeof(struct cs_etm_synth));
        cs_etm_synth.session = session;

        return perf_event__synthesize_attr(&cs_etm_synth.dummy_tool, attr, 1,
                                           &id, cs_etm__event_synth);
}

static int cs_etm__synth_events(struct cs_etm_auxtrace *etm,
                                struct perf_session *session)
{
        struct perf_evlist *evlist = session->evlist;
        struct perf_evsel *evsel;
        struct perf_event_attr attr;
        bool found = false;
        u64 id;
        int err;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel->attr.type == etm->pmu_type) {
                        found = true;
                        break;
                }
        }

        if (!found) {
                pr_debug("No selected events with CoreSight Trace data\n");
                return 0;
        }

        memset(&attr, 0, sizeof(struct perf_event_attr));
        attr.size = sizeof(struct perf_event_attr);
        attr.type = PERF_TYPE_HARDWARE;
        attr.sample_type = evsel->attr.sample_type & PERF_SAMPLE_MASK;
        attr.sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID |
                            PERF_SAMPLE_PERIOD;
        if (etm->timeless_decoding)
                attr.sample_type &= ~(u64)PERF_SAMPLE_TIME;
        else
                attr.sample_type |= PERF_SAMPLE_TIME;

        attr.exclude_user = evsel->attr.exclude_user;
        attr.exclude_kernel = evsel->attr.exclude_kernel;
        attr.exclude_hv = evsel->attr.exclude_hv;
        attr.exclude_host = evsel->attr.exclude_host;
        attr.exclude_guest = evsel->attr.exclude_guest;
        attr.sample_id_all = evsel->attr.sample_id_all;
        attr.read_format = evsel->attr.read_format;

        /* create new id val to be a fixed offset from evsel id */
        id = evsel->id[0] + 1000000000;

        if (!id)
                id = 1;

        if (etm->synth_opts.branches) {
                attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS;
                attr.sample_period = 1;
                attr.sample_type |= PERF_SAMPLE_ADDR;
                err = cs_etm__synth_event(session, &attr, id);
                if (err)
                        return err;
                etm->sample_branches = true;
                etm->branches_sample_type = attr.sample_type;
                etm->branches_id = id;
                id += 1;
                attr.sample_type &= ~(u64)PERF_SAMPLE_ADDR;
        }

        if (etm->synth_opts.last_branch)
                attr.sample_type |= PERF_SAMPLE_BRANCH_STACK;

        if (etm->synth_opts.instructions) {
                attr.config = PERF_COUNT_HW_INSTRUCTIONS;
                attr.sample_period = etm->synth_opts.period;
                etm->instructions_sample_period = attr.sample_period;
                err = cs_etm__synth_event(session, &attr, id);
                if (err)
                        return err;
                etm->sample_instructions = true;
                etm->instructions_sample_type = attr.sample_type;
                etm->instructions_id = id;
                id += 1;
        }

        return 0;
}

static int cs_etm__sample(struct cs_etm_queue *etmq)
{
        struct cs_etm_auxtrace *etm = etmq->etm;
        struct cs_etm_packet *tmp;
        int ret;
        u64 instrs_executed;

        instrs_executed = cs_etm__instr_count(etmq->packet);
        etmq->period_instructions += instrs_executed;

        /*
         * Record a branch when the last instruction in
         * PREV_PACKET is a branch.
         */
        if (etm->synth_opts.last_branch &&
            etmq->prev_packet &&
            etmq->prev_packet->sample_type == CS_ETM_RANGE &&
            etmq->prev_packet->last_instr_taken_branch)
                cs_etm__update_last_branch_rb(etmq);

        if (etm->sample_instructions &&
            etmq->period_instructions >= etm->instructions_sample_period) {
                /*
                 * Emit instruction sample periodically
                 * TODO: allow period to be defined in cycles and clock time
                 */

                /* Get number of instructions executed after the sample point */
                u64 instrs_over = etmq->period_instructions -
                        etm->instructions_sample_period;

                /*
                 * Calculate the address of the sampled instruction (-1 as
                 * sample is reported as though instruction has just been
                 * executed, but PC has not advanced to next instruction)
                 */
                u64 offset = (instrs_executed - instrs_over - 1);
                u64 addr = cs_etm__instr_addr(etmq->packet, offset);

                ret = cs_etm__synth_instruction_sample(
                        etmq, addr, etm->instructions_sample_period);
                if (ret)
                        return ret;

                /* Carry remaining instructions into next sample period */
                etmq->period_instructions = instrs_over;
        }

        if (etm->sample_branches && etmq->prev_packet) {
                bool generate_sample = false;

                /* Generate sample for tracing on packet */
                if (etmq->prev_packet->sample_type == CS_ETM_TRACE_ON)
                        generate_sample = true;

                /* Generate sample for branch taken packet */
                if (etmq->prev_packet->sample_type == CS_ETM_RANGE &&
                    etmq->prev_packet->last_instr_taken_branch)
                        generate_sample = true;

                if (generate_sample) {
                        ret = cs_etm__synth_branch_sample(etmq);
                        if (ret)
                                return ret;
                }
        }

        if (etm->sample_branches || etm->synth_opts.last_branch) {
                /*
                 * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
                 * the next incoming packet.
                 */
                tmp = etmq->packet;
                etmq->packet = etmq->prev_packet;
                etmq->prev_packet = tmp;
        }

        return 0;
}

static int cs_etm__flush(struct cs_etm_queue *etmq)
{
        int err = 0;
        struct cs_etm_auxtrace *etm = etmq->etm;
        struct cs_etm_packet *tmp;

        if (!etmq->prev_packet)
                return 0;

        /* Handle start tracing packet */
        if (etmq->prev_packet->sample_type == CS_ETM_EMPTY)
                goto swap_packet;

        if (etmq->etm->synth_opts.last_branch &&
            etmq->prev_packet->sample_type == CS_ETM_RANGE) {
                /*
                 * Generate a last branch event for the branches left in the
                 * circular buffer at the end of the trace.
                 *
                 * Use the address of the end of the last reported execution
                 * range
                 */
                u64 addr = cs_etm__last_executed_instr(etmq->prev_packet);

                err = cs_etm__synth_instruction_sample(
                        etmq, addr,
                        etmq->period_instructions);
                if (err)
                        return err;

                etmq->period_instructions = 0;

        }

        if (etm->sample_branches &&
            etmq->prev_packet->sample_type == CS_ETM_RANGE) {
                err = cs_etm__synth_branch_sample(etmq);
                if (err)
                        return err;
        }

swap_packet:
        if (etmq->etm->synth_opts.last_branch) {
                /*
                 * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
                 * the next incoming packet.
                 */
                tmp = etmq->packet;
                etmq->packet = etmq->prev_packet;
                etmq->prev_packet = tmp;
        }

        return err;
}

static int cs_etm__run_decoder(struct cs_etm_queue *etmq)

{
        struct cs_etm_auxtrace *etm = etmq->etm;
        struct cs_etm_buffer buffer;
        size_t buffer_used, processed;
        int err = 0;

        if (!etm->kernel_start)
                etm->kernel_start = machine__kernel_start(etm->machine);

        /* Go through each buffer in the queue and decode them one by one */
        while (1) {
                buffer_used = 0;
                memset(&buffer, 0, sizeof(buffer));
                err = cs_etm__get_trace(&buffer, etmq);
                if (err <= 0)
                        return err;
                /*
                 * We cannot assume consecutive blocks in the data file are
                 * contiguous, reset the decoder to force re-sync.
                 */
                err = cs_etm_decoder__reset(etmq->decoder);
                if (err != 0)
                        return err;

                /* Run trace decoder until buffer consumed or end of trace */
                do {
                        processed = 0;
                        err = cs_etm_decoder__process_data_block(
                                etmq->decoder,
                                etmq->offset,
                                &buffer.buf[buffer_used],
                                buffer.len - buffer_used,
                                &processed);
                        if (err)
                                return err;

                        etmq->offset += processed;
                        buffer_used += processed;

                        /* Process each packet in this chunk */
                        while (1) {
                                err = cs_etm_decoder__get_packet(etmq->decoder,
                                                                 etmq->packet);
                                if (err <= 0)
                                        /*
                                         * Stop processing this chunk on
                                         * end of data or error
                                         */
                                        break;

                                switch (etmq->packet->sample_type) {
                                case CS_ETM_RANGE:
                                        /*
                                         * If the packet contains an instruction
                                         * range, generate instruction sequence
                                         * events.
                                         */
                                        cs_etm__sample(etmq);
                                        break;
                                case CS_ETM_TRACE_ON:
                                        /*
                                         * Discontinuity in trace, flush
                                         * previous branch stack
                                         */
                                        cs_etm__flush(etmq);
                                        break;
                                case CS_ETM_EMPTY:
                                        /*
                                         * Should not receive empty packet,
                                         * report error.
                                         */
                                        pr_err("CS ETM Trace: empty packet\n");
                                        return -EINVAL;
                                default:
                                        break;
                                }
                        }
                } while (buffer.len > buffer_used);

                if (err == 0)
                        /* Flush any remaining branch stack entries */
                        err = cs_etm__flush(etmq);
        }

        return err;
}

static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
                                           pid_t tid, u64 time_)
{
        unsigned int i;
        struct auxtrace_queues *queues = &etm->queues;

        for (i = 0; i < queues->nr_queues; i++) {
                struct auxtrace_queue *queue = &etm->queues.queue_array[i];
                struct cs_etm_queue *etmq = queue->priv;

                if (etmq && ((tid == -1) || (etmq->tid == tid))) {
                        etmq->time = time_;
                        cs_etm__set_pid_tid_cpu(etm, queue);
                        cs_etm__run_decoder(etmq);
                }
        }

        return 0;
}

static int cs_etm__process_event(struct perf_session *session,
                                 union perf_event *event,
                                 struct perf_sample *sample,
                                 struct perf_tool *tool)
{
        int err = 0;
        u64 timestamp;
        struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
                                                   struct cs_etm_auxtrace,
                                                   auxtrace);

        if (dump_trace)
                return 0;

        if (!tool->ordered_events) {
                pr_err("CoreSight ETM Trace requires ordered events\n");
                return -EINVAL;
        }

        if (!etm->timeless_decoding)
                return -EINVAL;

        if (sample->time && (sample->time != (u64) -1))
                timestamp = sample->time;
        else
                timestamp = 0;

        if (timestamp || etm->timeless_decoding) {
                err = cs_etm__update_queues(etm);
                if (err)
                        return err;
        }

        if (event->header.type == PERF_RECORD_EXIT)
                return cs_etm__process_timeless_queues(etm,
                                                       event->fork.tid,
                                                       sample->time);

        return 0;
}

static int cs_etm__process_auxtrace_event(struct perf_session *session,
                                          union perf_event *event,
                                          struct perf_tool *tool __maybe_unused)
{
        struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
                                                   struct cs_etm_auxtrace,
                                                   auxtrace);
        if (!etm->data_queued) {
                struct auxtrace_buffer *buffer;
                off_t  data_offset;
                int fd = perf_data__fd(session->data);
                bool is_pipe = perf_data__is_pipe(session->data);
                int err;

                if (is_pipe)
                        data_offset = 0;
                else {
                        data_offset = lseek(fd, 0, SEEK_CUR);
                        if (data_offset == -1)
                                return -errno;
                }

                err = auxtrace_queues__add_event(&etm->queues, session,
                                                 event, data_offset, &buffer);
                if (err)
                        return err;

                if (dump_trace)
                        if (auxtrace_buffer__get_data(buffer, fd)) {
                                cs_etm__dump_event(etm, buffer);
                                auxtrace_buffer__put_data(buffer);
                        }
        }

        return 0;
}

static bool cs_etm__is_timeless_decoding(struct cs_etm_auxtrace *etm)
{
        struct perf_evsel *evsel;
        struct perf_evlist *evlist = etm->session->evlist;
        bool timeless_decoding = true;

        /*
         * Circle through the list of event and complain if we find one
         * with the time bit set.
         */
        evlist__for_each_entry(evlist, evsel) {
                if ((evsel->attr.sample_type & PERF_SAMPLE_TIME))
                        timeless_decoding = false;
        }

        return timeless_decoding;
}

static const char * const cs_etm_global_header_fmts[] = {
        [CS_HEADER_VERSION_0]   = "     Header version                 %llx\n",
        [CS_PMU_TYPE_CPUS]      = "     PMU type/num cpus              %llx\n",
        [CS_ETM_SNAPSHOT]       = "     Snapshot                       %llx\n",
};

static const char * const cs_etm_priv_fmts[] = {
        [CS_ETM_MAGIC]          = "     Magic number                   %llx\n",
        [CS_ETM_CPU]            = "     CPU                            %lld\n",
        [CS_ETM_ETMCR]          = "     ETMCR                          %llx\n",
        [CS_ETM_ETMTRACEIDR]    = "     ETMTRACEIDR                    %llx\n",
        [CS_ETM_ETMCCER]        = "     ETMCCER                        %llx\n",
        [CS_ETM_ETMIDR]         = "     ETMIDR                         %llx\n",
};

static const char * const cs_etmv4_priv_fmts[] = {
        [CS_ETM_MAGIC]          = "     Magic number                   %llx\n",
        [CS_ETM_CPU]            = "     CPU                            %lld\n",
        [CS_ETMV4_TRCCONFIGR]   = "     TRCCONFIGR                     %llx\n",
        [CS_ETMV4_TRCTRACEIDR]  = "     TRCTRACEIDR                    %llx\n",
        [CS_ETMV4_TRCIDR0]      = "     TRCIDR0                        %llx\n",
        [CS_ETMV4_TRCIDR1]      = "     TRCIDR1                        %llx\n",
        [CS_ETMV4_TRCIDR2]      = "     TRCIDR2                        %llx\n",
        [CS_ETMV4_TRCIDR8]      = "     TRCIDR8                        %llx\n",
        [CS_ETMV4_TRCAUTHSTATUS] = "    TRCAUTHSTATUS                  %llx\n",
};

static void cs_etm__print_auxtrace_info(u64 *val, int num)
{
        int i, j, cpu = 0;

        for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
                fprintf(stdout, cs_etm_global_header_fmts[i], val[i]);

        for (i = CS_HEADER_VERSION_0_MAX; cpu < num; cpu++) {
                if (val[i] == __perf_cs_etmv3_magic)
                        for (j = 0; j < CS_ETM_PRIV_MAX; j++, i++)
                                fprintf(stdout, cs_etm_priv_fmts[j], val[i]);
                else if (val[i] == __perf_cs_etmv4_magic)
                        for (j = 0; j < CS_ETMV4_PRIV_MAX; j++, i++)
                                fprintf(stdout, cs_etmv4_priv_fmts[j], val[i]);
                else
                        /* failure.. return */
                        return;
        }
}

int cs_etm__process_auxtrace_info(union perf_event *event,
                                  struct perf_session *session)
{
        struct auxtrace_info_event *auxtrace_info = &event->auxtrace_info;
        struct cs_etm_auxtrace *etm = NULL;
        struct int_node *inode;
        unsigned int pmu_type;
        int event_header_size = sizeof(struct perf_event_header);
        int info_header_size;
        int total_size = auxtrace_info->header.size;
        int priv_size = 0;
        int num_cpu;
        int err = 0, idx = -1;
        int i, j, k;
        u64 *ptr, *hdr = NULL;
        u64 **metadata = NULL;

        /*
         * sizeof(auxtrace_info_event::type) +
         * sizeof(auxtrace_info_event::reserved) == 8
         */
        info_header_size = 8;

        if (total_size < (event_header_size + info_header_size))
                return -EINVAL;

        priv_size = total_size - event_header_size - info_header_size;

        /* First the global part */
        ptr = (u64 *) auxtrace_info->priv;

        /* Look for version '0' of the header */
        if (ptr[0] != 0)
                return -EINVAL;

        hdr = zalloc(sizeof(*hdr) * CS_HEADER_VERSION_0_MAX);
        if (!hdr)
                return -ENOMEM;

        /* Extract header information - see cs-etm.h for format */
        for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
                hdr[i] = ptr[i];
        num_cpu = hdr[CS_PMU_TYPE_CPUS] & 0xffffffff;
        pmu_type = (unsigned int) ((hdr[CS_PMU_TYPE_CPUS] >> 32) &
                                    0xffffffff);

        /*
         * Create an RB tree for traceID-CPU# tuple. Since the conversion has
         * to be made for each packet that gets decoded, optimizing access in
         * anything other than a sequential array is worth doing.
         */
        traceid_list = intlist__new(NULL);
        if (!traceid_list) {
                err = -ENOMEM;
                goto err_free_hdr;
        }

        metadata = zalloc(sizeof(*metadata) * num_cpu);
        if (!metadata) {
                err = -ENOMEM;
                goto err_free_traceid_list;
        }

        /*
         * The metadata is stored in the auxtrace_info section and encodes
         * the configuration of the ARM embedded trace macrocell which is
         * required by the trace decoder to properly decode the trace due
         * to its highly compressed nature.
         */
        for (j = 0; j < num_cpu; j++) {
                if (ptr[i] == __perf_cs_etmv3_magic) {
                        metadata[j] = zalloc(sizeof(*metadata[j]) *
                                             CS_ETM_PRIV_MAX);
                        if (!metadata[j]) {
                                err = -ENOMEM;
                                goto err_free_metadata;
                        }
                        for (k = 0; k < CS_ETM_PRIV_MAX; k++)
                                metadata[j][k] = ptr[i + k];

                        /* The traceID is our handle */
                        idx = metadata[j][CS_ETM_ETMTRACEIDR];
                        i += CS_ETM_PRIV_MAX;
                } else if (ptr[i] == __perf_cs_etmv4_magic) {
                        metadata[j] = zalloc(sizeof(*metadata[j]) *
                                             CS_ETMV4_PRIV_MAX);
                        if (!metadata[j]) {
                                err = -ENOMEM;
                                goto err_free_metadata;
                        }
                        for (k = 0; k < CS_ETMV4_PRIV_MAX; k++)
                                metadata[j][k] = ptr[i + k];

                        /* The traceID is our handle */
                        idx = metadata[j][CS_ETMV4_TRCTRACEIDR];
                        i += CS_ETMV4_PRIV_MAX;
                }

                /* Get an RB node for this CPU */
                inode = intlist__findnew(traceid_list, idx);

                /* Something went wrong, no need to continue */
                if (!inode) {
                        err = PTR_ERR(inode);
                        goto err_free_metadata;
                }

                /*
                 * The node for that CPU should not be taken.
                 * Back out if that's the case.
                 */
                if (inode->priv) {
                        err = -EINVAL;
                        goto err_free_metadata;
                }
                /* All good, associate the traceID with the CPU# */
                inode->priv = &metadata[j][CS_ETM_CPU];
        }

        /*
         * Each of CS_HEADER_VERSION_0_MAX, CS_ETM_PRIV_MAX and
         * CS_ETMV4_PRIV_MAX mark how many double words are in the
         * global metadata, and each cpu's metadata respectively.
         * The following tests if the correct number of double words was
         * present in the auxtrace info section.
         */
        if (i * 8 != priv_size) {
                err = -EINVAL;
                goto err_free_metadata;
        }

        etm = zalloc(sizeof(*etm));

        if (!etm) {
                err = -ENOMEM;
                goto err_free_metadata;
        }

        err = auxtrace_queues__init(&etm->queues);
        if (err)
                goto err_free_etm;

        etm->session = session;
        etm->machine = &session->machines.host;

        etm->num_cpu = num_cpu;
        etm->pmu_type = pmu_type;
        etm->snapshot_mode = (hdr[CS_ETM_SNAPSHOT] != 0);
        etm->metadata = metadata;
        etm->auxtrace_type = auxtrace_info->type;
        etm->timeless_decoding = cs_etm__is_timeless_decoding(etm);

        etm->auxtrace.process_event = cs_etm__process_event;
        etm->auxtrace.process_auxtrace_event = cs_etm__process_auxtrace_event;
        etm->auxtrace.flush_events = cs_etm__flush_events;
        etm->auxtrace.free_events = cs_etm__free_events;
        etm->auxtrace.free = cs_etm__free;
        session->auxtrace = &etm->auxtrace;

        etm->unknown_thread = thread__new(999999999, 999999999);
        if (!etm->unknown_thread)
                goto err_free_queues;

        /*
         * Initialize list node so that at thread__zput() we can avoid
         * segmentation fault at list_del_init().
         */
        INIT_LIST_HEAD(&etm->unknown_thread->node);

        err = thread__set_comm(etm->unknown_thread, "unknown", 0);
        if (err)
                goto err_delete_thread;

        if (thread__init_map_groups(etm->unknown_thread, etm->machine))
                goto err_delete_thread;

        if (dump_trace) {
                cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu);
                return 0;
        }

        if (session->itrace_synth_opts && session->itrace_synth_opts->set) {
                etm->synth_opts = *session->itrace_synth_opts;
        } else {
                itrace_synth_opts__set_default(&etm->synth_opts);
                etm->synth_opts.callchain = false;
        }

        err = cs_etm__synth_events(etm, session);
        if (err)
                goto err_delete_thread;

        err = auxtrace_queues__process_index(&etm->queues, session);
        if (err)
                goto err_delete_thread;

        etm->data_queued = etm->queues.populated;

        return 0;

err_delete_thread:
        thread__zput(etm->unknown_thread);
err_free_queues:
        auxtrace_queues__free(&etm->queues);
        session->auxtrace = NULL;
err_free_etm:
        zfree(&etm);
err_free_metadata:
        /* No need to check @metadata[j], free(NULL) is supported */
        for (j = 0; j < num_cpu; j++)
                free(metadata[j]);
        zfree(&metadata);
err_free_traceid_list:
        intlist__delete(traceid_list);
err_free_hdr:
        zfree(&hdr);

        return -EINVAL;
}