// 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 <asm/bug.h>
#include <linux/coresight-pmu.h>
#include <linux/err.h>
#include <linux/list.h>
#include <linux/zalloc.h>
#include <stdlib.h>
#include <opencsd/c_api/opencsd_c_api.h>
#include <opencsd/etmv4/trc_pkt_types_etmv4.h>
#include <opencsd/ocsd_if_types.h>

#include "cs-etm.h"
#include "cs-etm-decoder.h"
#include "debug.h"
#include "intlist.h"

/* use raw logging */
#ifdef CS_DEBUG_RAW
#define CS_LOG_RAW_FRAMES
#ifdef CS_RAW_PACKED
#define CS_RAW_DEBUG_FLAGS (OCSD_DFRMTR_UNPACKED_RAW_OUT | \
                            OCSD_DFRMTR_PACKED_RAW_OUT)
#else
#define CS_RAW_DEBUG_FLAGS (OCSD_DFRMTR_UNPACKED_RAW_OUT)
#endif
#endif

struct cs_etm_decoder {
        void *data;
        void (*packet_printer)(const char *msg);
        dcd_tree_handle_t dcd_tree;
        cs_etm_mem_cb_type mem_access;
        ocsd_datapath_resp_t prev_return;
};

static u32
cs_etm_decoder__mem_access(const void *context,
                           const ocsd_vaddr_t address,
                           const ocsd_mem_space_acc_t mem_space __maybe_unused,
                           const u8 trace_chan_id,
                           const u32 req_size,
                           u8 *buffer)
{
        struct cs_etm_decoder *decoder = (struct cs_etm_decoder *) context;

        return decoder->mem_access(decoder->data, trace_chan_id,
                                   address, req_size, buffer);
}

int cs_etm_decoder__add_mem_access_cb(struct cs_etm_decoder *decoder,
                                      u64 start, u64 end,
                                      cs_etm_mem_cb_type cb_func)
{
        decoder->mem_access = cb_func;

        if (ocsd_dt_add_callback_trcid_mem_acc(decoder->dcd_tree, start, end,
                                               OCSD_MEM_SPACE_ANY,
                                               cs_etm_decoder__mem_access,
                                               decoder))
                return -1;

        return 0;
}

int cs_etm_decoder__reset(struct cs_etm_decoder *decoder)
{
        ocsd_datapath_resp_t dp_ret;

        decoder->prev_return = OCSD_RESP_CONT;

        dp_ret = ocsd_dt_process_data(decoder->dcd_tree, OCSD_OP_RESET,
                                      0, 0, NULL, NULL);
        if (OCSD_DATA_RESP_IS_FATAL(dp_ret))
                return -1;

        return 0;
}

int cs_etm_decoder__get_packet(struct cs_etm_packet_queue *packet_queue,
                               struct cs_etm_packet *packet)
{
        if (!packet_queue || !packet)
                return -EINVAL;

        /* Nothing to do, might as well just return */
        if (packet_queue->packet_count == 0)
                return 0;
        /*
         * The queueing process in function cs_etm_decoder__buffer_packet()
         * increments the tail *before* using it.  This is somewhat counter
         * intuitive but it has the advantage of centralizing tail management
         * at a single location.  Because of that we need to follow the same
         * heuristic with the head, i.e we increment it before using its
         * value.  Otherwise the first element of the packet queue is not
         * used.
         */
        packet_queue->head = (packet_queue->head + 1) &
                             (CS_ETM_PACKET_MAX_BUFFER - 1);

        *packet = packet_queue->packet_buffer[packet_queue->head];

        packet_queue->packet_count--;

        return 1;
}

static int cs_etm_decoder__gen_etmv3_config(struct cs_etm_trace_params *params,
                                            ocsd_etmv3_cfg *config)
{
        config->reg_idr = params->etmv3.reg_idr;
        config->reg_ctrl = params->etmv3.reg_ctrl;
        config->reg_ccer = params->etmv3.reg_ccer;
        config->reg_trc_id = params->etmv3.reg_trc_id;
        config->arch_ver = ARCH_V7;
        config->core_prof = profile_CortexA;

        return 0;
}

static void cs_etm_decoder__gen_etmv4_config(struct cs_etm_trace_params *params,
                                             ocsd_etmv4_cfg *config)
{
        config->reg_configr = params->etmv4.reg_configr;
        config->reg_traceidr = params->etmv4.reg_traceidr;
        config->reg_idr0 = params->etmv4.reg_idr0;
        config->reg_idr1 = params->etmv4.reg_idr1;
        config->reg_idr2 = params->etmv4.reg_idr2;
        config->reg_idr8 = params->etmv4.reg_idr8;
        config->reg_idr9 = 0;
        config->reg_idr10 = 0;
        config->reg_idr11 = 0;
        config->reg_idr12 = 0;
        config->reg_idr13 = 0;
        config->arch_ver = ARCH_V8;
        config->core_prof = profile_CortexA;
}

static void cs_etm_decoder__print_str_cb(const void *p_context,
                                         const char *msg,
                                         const int str_len)
{
        if (p_context && str_len)
                ((struct cs_etm_decoder *)p_context)->packet_printer(msg);
}

static int
cs_etm_decoder__init_def_logger_printing(struct cs_etm_decoder_params *d_params,
                                         struct cs_etm_decoder *decoder)
{
        int ret = 0;

        if (d_params->packet_printer == NULL)
                return -1;

        decoder->packet_printer = d_params->packet_printer;

        /*
         * Set up a library default logger to process any printers
         * (packet/raw frame) we add later.
         */
        ret = ocsd_def_errlog_init(OCSD_ERR_SEV_ERROR, 1);
        if (ret != 0)
                return -1;

        /* no stdout / err / file output */
        ret = ocsd_def_errlog_config_output(C_API_MSGLOGOUT_FLG_NONE, NULL);
        if (ret != 0)
                return -1;

        /*
         * Set the string CB for the default logger, passes strings to
         * perf print logger.
         */
        ret = ocsd_def_errlog_set_strprint_cb(decoder->dcd_tree,
                                              (void *)decoder,
                                              cs_etm_decoder__print_str_cb);
        if (ret != 0)
                ret = -1;

        return 0;
}

#ifdef CS_LOG_RAW_FRAMES
static void
cs_etm_decoder__init_raw_frame_logging(struct cs_etm_decoder_params *d_params,
                                       struct cs_etm_decoder *decoder)
{
        /* Only log these during a --dump operation */
        if (d_params->operation == CS_ETM_OPERATION_PRINT) {
                /* set up a library default logger to process the
                 *  raw frame printer we add later
                 */
                ocsd_def_errlog_init(OCSD_ERR_SEV_ERROR, 1);

                /* no stdout / err / file output */
                ocsd_def_errlog_config_output(C_API_MSGLOGOUT_FLG_NONE, NULL);

                /* set the string CB for the default logger,
                 * passes strings to perf print logger.
                 */
                ocsd_def_errlog_set_strprint_cb(decoder->dcd_tree,
                                                (void *)decoder,
                                                cs_etm_decoder__print_str_cb);

                /* use the built in library printer for the raw frames */
                ocsd_dt_set_raw_frame_printer(decoder->dcd_tree,
                                              CS_RAW_DEBUG_FLAGS);
        }
}
#else
static void
cs_etm_decoder__init_raw_frame_logging(
                struct cs_etm_decoder_params *d_params __maybe_unused,
                struct cs_etm_decoder *decoder __maybe_unused)
{
}
#endif

static int cs_etm_decoder__create_packet_printer(struct cs_etm_decoder *decoder,
                                                 const char *decoder_name,
                                                 void *trace_config)
{
        u8 csid;

        if (ocsd_dt_create_decoder(decoder->dcd_tree, decoder_name,
                                   OCSD_CREATE_FLG_PACKET_PROC,
                                   trace_config, &csid))
                return -1;

        if (ocsd_dt_set_pkt_protocol_printer(decoder->dcd_tree, csid, 0))
                return -1;

        return 0;
}

static int
cs_etm_decoder__create_etm_packet_printer(struct cs_etm_trace_params *t_params,
                                          struct cs_etm_decoder *decoder)
{
        const char *decoder_name;
        ocsd_etmv3_cfg config_etmv3;
        ocsd_etmv4_cfg trace_config_etmv4;
        void *trace_config;

        switch (t_params->protocol) {
        case CS_ETM_PROTO_ETMV3:
        case CS_ETM_PROTO_PTM:
                cs_etm_decoder__gen_etmv3_config(t_params, &config_etmv3);
                decoder_name = (t_params->protocol == CS_ETM_PROTO_ETMV3) ?
                                                        OCSD_BUILTIN_DCD_ETMV3 :
                                                        OCSD_BUILTIN_DCD_PTM;
                trace_config = &config_etmv3;
                break;
        case CS_ETM_PROTO_ETMV4i:
                cs_etm_decoder__gen_etmv4_config(t_params, &trace_config_etmv4);
                decoder_name = OCSD_BUILTIN_DCD_ETMV4I;
                trace_config = &trace_config_etmv4;
                break;
        default:
                return -1;
        }

        return cs_etm_decoder__create_packet_printer(decoder,
                                                     decoder_name,
                                                     trace_config);
}

static ocsd_datapath_resp_t
cs_etm_decoder__do_soft_timestamp(struct cs_etm_queue *etmq,
                                  struct cs_etm_packet_queue *packet_queue,
                                  const uint8_t trace_chan_id)
{
        /* No timestamp packet has been received, nothing to do */
        if (!packet_queue->cs_timestamp)
                return OCSD_RESP_CONT;

        packet_queue->cs_timestamp = packet_queue->next_cs_timestamp;

        /* Estimate the timestamp for the next range packet */
        packet_queue->next_cs_timestamp += packet_queue->instr_count;
        packet_queue->instr_count = 0;

        /* Tell the front end which traceid_queue needs attention */
        cs_etm__etmq_set_traceid_queue_timestamp(etmq, trace_chan_id);

        return OCSD_RESP_WAIT;
}

static ocsd_datapath_resp_t
cs_etm_decoder__do_hard_timestamp(struct cs_etm_queue *etmq,
                                  const ocsd_generic_trace_elem *elem,
                                  const uint8_t trace_chan_id,
                                  const ocsd_trc_index_t indx)
{
        struct cs_etm_packet_queue *packet_queue;

        /* First get the packet queue for this traceID */
        packet_queue = cs_etm__etmq_get_packet_queue(etmq, trace_chan_id);
        if (!packet_queue)
                return OCSD_RESP_FATAL_SYS_ERR;

        /*
         * We've seen a timestamp packet before - simply record the new value.
         * Function do_soft_timestamp() will report the value to the front end,
         * hence asking the decoder to keep decoding rather than stopping.
         */
        if (packet_queue->cs_timestamp) {
                packet_queue->next_cs_timestamp = elem->timestamp;
                return OCSD_RESP_CONT;
        }


        if (!elem->timestamp) {
                /*
                 * Zero timestamps can be seen due to misconfiguration or hardware bugs.
                 * Warn once, and don't try to subtract instr_count as it would result in an
                 * underflow.
                 */
                packet_queue->cs_timestamp = 0;
                WARN_ONCE(true, "Zero Coresight timestamp found at Idx:%" OCSD_TRC_IDX_STR
                                ". Decoding may be improved with --itrace=Z...\n", indx);
        } else if (packet_queue->instr_count > elem->timestamp) {
                /*
                 * Sanity check that the elem->timestamp - packet_queue->instr_count would not
                 * result in an underflow. Warn and clamp at 0 if it would.
                 */
                packet_queue->cs_timestamp = 0;
                pr_err("Timestamp calculation underflow at Idx:%" OCSD_TRC_IDX_STR "\n", indx);
        } else {
                /*
                 * This is the first timestamp we've seen since the beginning of traces
                 * or a discontinuity.  Since timestamps packets are generated *after*
                 * range packets have been generated, we need to estimate the time at
                 * which instructions started by subtracting the number of instructions
                 * executed to the timestamp.
                 */
                packet_queue->cs_timestamp = elem->timestamp - packet_queue->instr_count;
        }
        packet_queue->next_cs_timestamp = elem->timestamp;
        packet_queue->instr_count = 0;

        /* Tell the front end which traceid_queue needs attention */
        cs_etm__etmq_set_traceid_queue_timestamp(etmq, trace_chan_id);

        /* Halt processing until we are being told to proceed */
        return OCSD_RESP_WAIT;
}

static void
cs_etm_decoder__reset_timestamp(struct cs_etm_packet_queue *packet_queue)
{
        packet_queue->cs_timestamp = 0;
        packet_queue->next_cs_timestamp = 0;
        packet_queue->instr_count = 0;
}

static ocsd_datapath_resp_t
cs_etm_decoder__buffer_packet(struct cs_etm_packet_queue *packet_queue,
                              const u8 trace_chan_id,
                              enum cs_etm_sample_type sample_type)
{
        u32 et = 0;
        int cpu;

        if (packet_queue->packet_count >= CS_ETM_PACKET_MAX_BUFFER - 1)
                return OCSD_RESP_FATAL_SYS_ERR;

        if (cs_etm__get_cpu(trace_chan_id, &cpu) < 0)
                return OCSD_RESP_FATAL_SYS_ERR;

        et = packet_queue->tail;
        et = (et + 1) & (CS_ETM_PACKET_MAX_BUFFER - 1);
        packet_queue->tail = et;
        packet_queue->packet_count++;

        packet_queue->packet_buffer[et].sample_type = sample_type;
        packet_queue->packet_buffer[et].isa = CS_ETM_ISA_UNKNOWN;
        packet_queue->packet_buffer[et].cpu = cpu;
        packet_queue->packet_buffer[et].start_addr = CS_ETM_INVAL_ADDR;
        packet_queue->packet_buffer[et].end_addr = CS_ETM_INVAL_ADDR;
        packet_queue->packet_buffer[et].instr_count = 0;
        packet_queue->packet_buffer[et].last_instr_taken_branch = false;
        packet_queue->packet_buffer[et].last_instr_size = 0;
        packet_queue->packet_buffer[et].last_instr_type = 0;
        packet_queue->packet_buffer[et].last_instr_subtype = 0;
        packet_queue->packet_buffer[et].last_instr_cond = 0;
        packet_queue->packet_buffer[et].flags = 0;
        packet_queue->packet_buffer[et].exception_number = UINT32_MAX;
        packet_queue->packet_buffer[et].trace_chan_id = trace_chan_id;

        if (packet_queue->packet_count == CS_ETM_PACKET_MAX_BUFFER - 1)
                return OCSD_RESP_WAIT;

        return OCSD_RESP_CONT;
}

static ocsd_datapath_resp_t
cs_etm_decoder__buffer_range(struct cs_etm_queue *etmq,
                             struct cs_etm_packet_queue *packet_queue,
                             const ocsd_generic_trace_elem *elem,
                             const uint8_t trace_chan_id)
{
        int ret = 0;
        struct cs_etm_packet *packet;

        ret = cs_etm_decoder__buffer_packet(packet_queue, trace_chan_id,
                                            CS_ETM_RANGE);
        if (ret != OCSD_RESP_CONT && ret != OCSD_RESP_WAIT)
                return ret;

        packet = &packet_queue->packet_buffer[packet_queue->tail];

        switch (elem->isa) {
        case ocsd_isa_aarch64:
                packet->isa = CS_ETM_ISA_A64;
                break;
        case ocsd_isa_arm:
                packet->isa = CS_ETM_ISA_A32;
                break;
        case ocsd_isa_thumb2:
                packet->isa = CS_ETM_ISA_T32;
                break;
        case ocsd_isa_tee:
        case ocsd_isa_jazelle:
        case ocsd_isa_custom:
        case ocsd_isa_unknown:
        default:
                packet->isa = CS_ETM_ISA_UNKNOWN;
        }

        packet->start_addr = elem->st_addr;
        packet->end_addr = elem->en_addr;
        packet->instr_count = elem->num_instr_range;
        packet->last_instr_type = elem->last_i_type;
        packet->last_instr_subtype = elem->last_i_subtype;
        packet->last_instr_cond = elem->last_instr_cond;

        if (elem->last_i_type == OCSD_INSTR_BR || elem->last_i_type == OCSD_INSTR_BR_INDIRECT)
                packet->last_instr_taken_branch = elem->last_instr_exec;
        else
                packet->last_instr_taken_branch = false;

        packet->last_instr_size = elem->last_instr_sz;

        /* per-thread scenario, no need to generate a timestamp */
        if (cs_etm__etmq_is_timeless(etmq))
                goto out;

        /*
         * The packet queue is full and we haven't seen a timestamp (had we
         * seen one the packet queue wouldn't be full).  Let the front end
         * deal with it.
         */
        if (ret == OCSD_RESP_WAIT)
                goto out;

        packet_queue->instr_count += elem->num_instr_range;
        /* Tell the front end we have a new timestamp to process */
        ret = cs_etm_decoder__do_soft_timestamp(etmq, packet_queue,
                                                trace_chan_id);
out:
        return ret;
}

static ocsd_datapath_resp_t
cs_etm_decoder__buffer_discontinuity(struct cs_etm_packet_queue *queue,
                                     const uint8_t trace_chan_id)
{
        /*
         * Something happened and who knows when we'll get new traces so
         * reset time statistics.
         */
        cs_etm_decoder__reset_timestamp(queue);
        return cs_etm_decoder__buffer_packet(queue, trace_chan_id,
                                             CS_ETM_DISCONTINUITY);
}

static ocsd_datapath_resp_t
cs_etm_decoder__buffer_exception(struct cs_etm_packet_queue *queue,
                                 const ocsd_generic_trace_elem *elem,
                                 const uint8_t trace_chan_id)
{       int ret = 0;
        struct cs_etm_packet *packet;

        ret = cs_etm_decoder__buffer_packet(queue, trace_chan_id,
                                            CS_ETM_EXCEPTION);
        if (ret != OCSD_RESP_CONT && ret != OCSD_RESP_WAIT)
                return ret;

        packet = &queue->packet_buffer[queue->tail];
        packet->exception_number = elem->exception_number;

        return ret;
}

static ocsd_datapath_resp_t
cs_etm_decoder__buffer_exception_ret(struct cs_etm_packet_queue *queue,
                                     const uint8_t trace_chan_id)
{
        return cs_etm_decoder__buffer_packet(queue, trace_chan_id,
                                             CS_ETM_EXCEPTION_RET);
}

static ocsd_datapath_resp_t
cs_etm_decoder__set_tid(struct cs_etm_queue *etmq,
                        struct cs_etm_packet_queue *packet_queue,
                        const ocsd_generic_trace_elem *elem,
                        const uint8_t trace_chan_id)
{
        pid_t tid = -1;
        static u64 pid_fmt;
        int ret;

        /*
         * As all the ETMs run at the same exception level, the system should
         * have the same PID format crossing CPUs.  So cache the PID format
         * and reuse it for sequential decoding.
         */
        if (!pid_fmt) {
                ret = cs_etm__get_pid_fmt(trace_chan_id, &pid_fmt);
                if (ret)
                        return OCSD_RESP_FATAL_SYS_ERR;
        }

        /*
         * Process the PE_CONTEXT packets if we have a valid contextID or VMID.
         * If the kernel is running at EL2, the PID is traced in CONTEXTIDR_EL2
         * as VMID, Bit ETM_OPT_CTXTID2 is set in this case.
         */
        switch (pid_fmt) {
        case BIT(ETM_OPT_CTXTID):
                if (elem->context.ctxt_id_valid)
                        tid = elem->context.context_id;
                break;
        case BIT(ETM_OPT_CTXTID2):
                if (elem->context.vmid_valid)
                        tid = elem->context.vmid;
                break;
        default:
                break;
        }

        if (tid == -1)
                return OCSD_RESP_CONT;

        if (cs_etm__etmq_set_tid(etmq, tid, trace_chan_id))
                return OCSD_RESP_FATAL_SYS_ERR;

        /*
         * A timestamp is generated after a PE_CONTEXT element so make sure
         * to rely on that coming one.
         */
        cs_etm_decoder__reset_timestamp(packet_queue);

        return OCSD_RESP_CONT;
}

static ocsd_datapath_resp_t cs_etm_decoder__gen_trace_elem_printer(
                                const void *context,
                                const ocsd_trc_index_t indx,
                                const u8 trace_chan_id __maybe_unused,
                                const ocsd_generic_trace_elem *elem)
{
        ocsd_datapath_resp_t resp = OCSD_RESP_CONT;
        struct cs_etm_decoder *decoder = (struct cs_etm_decoder *) context;
        struct cs_etm_queue *etmq = decoder->data;
        struct cs_etm_packet_queue *packet_queue;

        /* First get the packet queue for this traceID */
        packet_queue = cs_etm__etmq_get_packet_queue(etmq, trace_chan_id);
        if (!packet_queue)
                return OCSD_RESP_FATAL_SYS_ERR;

        switch (elem->elem_type) {
        case OCSD_GEN_TRC_ELEM_UNKNOWN:
                break;
        case OCSD_GEN_TRC_ELEM_EO_TRACE:
        case OCSD_GEN_TRC_ELEM_NO_SYNC:
        case OCSD_GEN_TRC_ELEM_TRACE_ON:
                resp = cs_etm_decoder__buffer_discontinuity(packet_queue,
                                                            trace_chan_id);
                break;
        case OCSD_GEN_TRC_ELEM_INSTR_RANGE:
                resp = cs_etm_decoder__buffer_range(etmq, packet_queue, elem,
                                                    trace_chan_id);
                break;
        case OCSD_GEN_TRC_ELEM_EXCEPTION:
                resp = cs_etm_decoder__buffer_exception(packet_queue, elem,
                                                        trace_chan_id);
                break;
        case OCSD_GEN_TRC_ELEM_EXCEPTION_RET:
                resp = cs_etm_decoder__buffer_exception_ret(packet_queue,
                                                            trace_chan_id);
                break;
        case OCSD_GEN_TRC_ELEM_TIMESTAMP:
                resp = cs_etm_decoder__do_hard_timestamp(etmq, elem,
                                                         trace_chan_id,
                                                         indx);
                break;
        case OCSD_GEN_TRC_ELEM_PE_CONTEXT:
                resp = cs_etm_decoder__set_tid(etmq, packet_queue,
                                               elem, trace_chan_id);
                break;
        /* Unused packet types */
        case OCSD_GEN_TRC_ELEM_I_RANGE_NOPATH:
        case OCSD_GEN_TRC_ELEM_ADDR_NACC:
        case OCSD_GEN_TRC_ELEM_CYCLE_COUNT:
        case OCSD_GEN_TRC_ELEM_ADDR_UNKNOWN:
        case OCSD_GEN_TRC_ELEM_EVENT:
        case OCSD_GEN_TRC_ELEM_SWTRACE:
        case OCSD_GEN_TRC_ELEM_CUSTOM:
        case OCSD_GEN_TRC_ELEM_SYNC_MARKER:
        case OCSD_GEN_TRC_ELEM_MEMTRANS:
        default:
                break;
        }

        return resp;
}

static int cs_etm_decoder__create_etm_packet_decoder(
                                        struct cs_etm_trace_params *t_params,
                                        struct cs_etm_decoder *decoder)
{
        const char *decoder_name;
        ocsd_etmv3_cfg config_etmv3;
        ocsd_etmv4_cfg trace_config_etmv4;
        void *trace_config;
        u8 csid;

        switch (t_params->protocol) {
        case CS_ETM_PROTO_ETMV3:
        case CS_ETM_PROTO_PTM:
                cs_etm_decoder__gen_etmv3_config(t_params, &config_etmv3);
                decoder_name = (t_params->protocol == CS_ETM_PROTO_ETMV3) ?
                                                        OCSD_BUILTIN_DCD_ETMV3 :
                                                        OCSD_BUILTIN_DCD_PTM;
                trace_config = &config_etmv3;
                break;
        case CS_ETM_PROTO_ETMV4i:
                cs_etm_decoder__gen_etmv4_config(t_params, &trace_config_etmv4);
                decoder_name = OCSD_BUILTIN_DCD_ETMV4I;
                trace_config = &trace_config_etmv4;
                break;
        default:
                return -1;
        }

        if (ocsd_dt_create_decoder(decoder->dcd_tree,
                                     decoder_name,
                                     OCSD_CREATE_FLG_FULL_DECODER,
                                     trace_config, &csid))
                return -1;

        if (ocsd_dt_set_gen_elem_outfn(decoder->dcd_tree,
                                       cs_etm_decoder__gen_trace_elem_printer,
                                       decoder))
                return -1;

        return 0;
}

static int
cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params,
                                   struct cs_etm_trace_params *t_params,
                                   struct cs_etm_decoder *decoder)
{
        if (d_params->operation == CS_ETM_OPERATION_PRINT)
                return cs_etm_decoder__create_etm_packet_printer(t_params,
                                                                 decoder);
        else if (d_params->operation == CS_ETM_OPERATION_DECODE)
                return cs_etm_decoder__create_etm_packet_decoder(t_params,
                                                                 decoder);

        return -1;
}

struct cs_etm_decoder *
cs_etm_decoder__new(int num_cpu, struct cs_etm_decoder_params *d_params,
                    struct cs_etm_trace_params t_params[])
{
        struct cs_etm_decoder *decoder;
        ocsd_dcd_tree_src_t format;
        u32 flags;
        int i, ret;

        if ((!t_params) || (!d_params))
                return NULL;

        decoder = zalloc(sizeof(*decoder));

        if (!decoder)
                return NULL;

        decoder->data = d_params->data;
        decoder->prev_return = OCSD_RESP_CONT;
        format = (d_params->formatted ? OCSD_TRC_SRC_FRAME_FORMATTED :
                                         OCSD_TRC_SRC_SINGLE);
        flags = 0;
        flags |= (d_params->fsyncs ? OCSD_DFRMTR_HAS_FSYNCS : 0);
        flags |= (d_params->hsyncs ? OCSD_DFRMTR_HAS_HSYNCS : 0);
        flags |= (d_params->frame_aligned ? OCSD_DFRMTR_FRAME_MEM_ALIGN : 0);

        /*
         * Drivers may add barrier frames when used with perf, set up to
         * handle this. Barriers const of FSYNC packet repeated 4 times.
         */
        flags |= OCSD_DFRMTR_RESET_ON_4X_FSYNC;

        /* Create decode tree for the data source */
        decoder->dcd_tree = ocsd_create_dcd_tree(format, flags);

        if (decoder->dcd_tree == 0)
                goto err_free_decoder;

        /* init library print logging support */
        ret = cs_etm_decoder__init_def_logger_printing(d_params, decoder);
        if (ret != 0)
                goto err_free_decoder;

        /* init raw frame logging if required */
        cs_etm_decoder__init_raw_frame_logging(d_params, decoder);

        for (i = 0; i < num_cpu; i++) {
                ret = cs_etm_decoder__create_etm_decoder(d_params,
                                                         &t_params[i],
                                                         decoder);
                if (ret != 0)
                        goto err_free_decoder;
        }

        return decoder;

err_free_decoder:
        cs_etm_decoder__free(decoder);
        return NULL;
}

int cs_etm_decoder__process_data_block(struct cs_etm_decoder *decoder,
                                       u64 indx, const u8 *buf,
                                       size_t len, size_t *consumed)
{
        int ret = 0;
        ocsd_datapath_resp_t cur = OCSD_RESP_CONT;
        ocsd_datapath_resp_t prev_return = decoder->prev_return;
        size_t processed = 0;
        u32 count;

        while (processed < len) {
                if (OCSD_DATA_RESP_IS_WAIT(prev_return)) {
                        cur = ocsd_dt_process_data(decoder->dcd_tree,
                                                   OCSD_OP_FLUSH,
                                                   0,
                                                   0,
                                                   NULL,
                                                   NULL);
                } else if (OCSD_DATA_RESP_IS_CONT(prev_return)) {
                        cur = ocsd_dt_process_data(decoder->dcd_tree,
                                                   OCSD_OP_DATA,
                                                   indx + processed,
                                                   len - processed,
                                                   &buf[processed],
                                                   &count);
                        processed += count;
                } else {
                        ret = -EINVAL;
                        break;
                }

                /*
                 * Return to the input code if the packet buffer is full.
                 * Flushing will get done once the packet buffer has been
                 * processed.
                 */
                if (OCSD_DATA_RESP_IS_WAIT(cur))
                        break;

                prev_return = cur;
        }

        decoder->prev_return = cur;
        *consumed = processed;

        return ret;
}

void cs_etm_decoder__free(struct cs_etm_decoder *decoder)
{
        if (!decoder)
                return;

        ocsd_destroy_dcd_tree(decoder->dcd_tree);
        decoder->dcd_tree = NULL;
        free(decoder);
}