Introduce N-Trace format message encoder, based on "RISC-V n-trace (Nexus-based Trace) Specificationand" Version 1.0.
Add generation, encoding and sending logic for ProgTraceSync message Signed-off-by: Konstantin Semichastnov <[email protected]> --- hw/riscv/rv-trace-messages.c | 154 +++++++++++++++++++++++++++++++++++++++++++ hw/riscv/rv-trace-messages.h | 1 + hw/riscv/trace-encoder.c | 29 +++++++- hw/riscv/trace-encoder.h | 1 + 4 files changed, 184 insertions(+), 1 deletion(-) diff --git a/hw/riscv/rv-trace-messages.c b/hw/riscv/rv-trace-messages.c index 932f3ae499..0b90d6a437 100644 --- a/hw/riscv/rv-trace-messages.c +++ b/hw/riscv/rv-trace-messages.c @@ -338,3 +338,157 @@ size_t rv_etrace_gen_encoded_format1(uint8_t *buf, return HEADER_SIZE + header.length; } + +#define MDO_BITS_NUM 6 +#define MSEO_BITS_NUM 2 + +#define MSEO_VAR_FIELD_FINISHED 0b01 +#define MSEO_END_OF_MESSAGE 0b11 + +typedef enum { + FIELD_END = 0, + FIELD_FIXED, + FIELD_VAR, +} NTraceFieldType; + +typedef enum { + WIDTH_TCODE = 6, + WIDTH_SYNC = 4, + WIDTH_ICNT = 22, + WIDTH_FADDR = 63, +} NTraceFieldWidth; + +typedef enum { + TCODE_PROG_TRACE_SYNC = 0x9, +} NTraceTcodeFieldValues; + +typedef enum { + SYNC_PERIODIC = 2, + SYNC_TRACE_ENABLED = 5, +} NTraceSyncFieldValues; + +typedef struct NTraceFieldPayload { + NTraceFieldType type; + NTraceFieldWidth width; + uint64_t value; +} NTraceFieldPayload; + +#define PAYLOAD_TCODE(val) \ + { \ + .type = FIELD_FIXED, \ + .width = WIDTH_TCODE, \ + .value = (val), \ + } + +#define PAYLOAD_SYNC(val) \ + { \ + .type = FIELD_FIXED, \ + .width = WIDTH_SYNC, \ + .value = (val), \ + } + +#define PAYLOAD_ICNT(val) \ + { \ + .type = FIELD_VAR, \ + .width = WIDTH_ICNT, \ + .value = (val), \ + } + +#define PAYLOAD_FADDR(val) \ + { \ + .type = FIELD_VAR, \ + .width = WIDTH_FADDR, \ + .value = (val), \ + } +#define PAYLOAD_END() \ + { \ + .type = FIELD_END, \ + .width = 0, \ + .value = 0, \ + } + +static size_t rv_ntrace_gen_encoded_msg(uint8_t *buf, + const NTraceFieldPayload *payload) +{ + uint8_t buf_byte = 0; + uint8_t packed_bit = 0; + uint8_t packed_cur = 0; + uint8_t nr_move = 0; + + /* + * as described in "Chapter 3. N-Trace Transmission Protocol" of N-Trace + * spec each byte has only bits[7:2] filled with data, called MDO bits. + * Lowest 2 bits[1:0] are called MSEO bits and used to signal about + * boundaries between message fields and messages + */ + + while (payload->type != FIELD_END) { + for (uint8_t offset = 0; offset < payload->width; offset += nr_move) { + nr_move = MIN(MDO_BITS_NUM - packed_bit, payload->width - offset); + uint8_t chunk = extract64(payload->value, offset, nr_move); + + packed_cur = deposit32(packed_cur, packed_bit, nr_move, chunk); + packed_bit += nr_move; + + if (packed_bit == MDO_BITS_NUM) { + buf[buf_byte++] = packed_cur << MSEO_BITS_NUM; + packed_bit = 0; + packed_cur = 0; + } + } + + /* + * if field has variable length - last byte of this field should have + * MSEO (lowest 2) bits set to 01, and zero filled to end of byte + * + * N-Trace spec: 3.1. MSEO Sequences. + */ + if (payload->type == FIELD_VAR) { + if (packed_bit != 0) { + /* last chunk was not finished, leave remaining bits cleared */ + buf[buf_byte++] = packed_cur << MSEO_BITS_NUM; + packed_bit = 0; + packed_cur = 0; + } + + /* correct last chunk MSEO bits */ + buf[buf_byte - 1] = deposit32(buf[buf_byte - 1], 0, + MSEO_BITS_NUM, + MSEO_VAR_FIELD_FINISHED); + } + + payload++; + } + + if (packed_bit != 0) { + /* last chunk was not finished, so finish it now */ + buf[buf_byte++] = packed_cur; + } + + /* + * last byte of message should have MSEO (lowest 2) bits set to 11 + * + * N-Trace spec: 3.1. MSEO Sequences. + */ + buf[buf_byte - 1] = deposit32(buf[buf_byte - 1], 0, + MSEO_BITS_NUM, + MSEO_END_OF_MESSAGE); + + return buf_byte; +} + +size_t rv_ntrace_gen_encoded_prog_trace_sync_msg(uint8_t *buf, uint64_t faddr) +{ + const NTraceFieldPayload msg_fields[] = { + PAYLOAD_TCODE(TCODE_PROG_TRACE_SYNC), + /* SRC field is not supported for now */ + PAYLOAD_SYNC(SYNC_TRACE_ENABLED), + PAYLOAD_ICNT(0), + PAYLOAD_FADDR(faddr), + /* TSTAMP field is not supported for now */ + PAYLOAD_END(), + }; + + return rv_ntrace_gen_encoded_msg(buf, msg_fields); +} + diff --git a/hw/riscv/rv-trace-messages.h b/hw/riscv/rv-trace-messages.h index 6f700eac8e..635e498393 100644 --- a/hw/riscv/rv-trace-messages.h +++ b/hw/riscv/rv-trace-messages.h @@ -37,4 +37,5 @@ size_t rv_etrace_gen_encoded_format1(uint8_t *buf, uint64_t addr, bool notify, bool updiscon); +size_t rv_ntrace_gen_encoded_prog_trace_sync_msg(uint8_t *buf, uint64_t faddr); #endif diff --git a/hw/riscv/trace-encoder.c b/hw/riscv/trace-encoder.c index 34c8f60ce1..10e52e207e 100644 --- a/hw/riscv/trace-encoder.c +++ b/hw/riscv/trace-encoder.c @@ -255,7 +255,13 @@ static void trencoder_te_ctrl_postw(RegisterInfo *reg, uint64_t val) if (!te->trace_running && trTeInstTracing) { /* Starting trace. Ask the CPU for the first trace insn */ if (te->ntrace) { - /* send ProgTraceSync message */ + /* + * N-Trace require to trace from very first instruction, + * not from next instruction, after enabling the trace, + * like E-Trace. So we need to send message here, instead of + * using te->trace_next_insn + */ + trencoder_send_prog_trace_sync(OBJECT(te), env->pc); } else { te->trace_next_insn = true; } @@ -508,6 +514,27 @@ void trencoder_set_first_trace_insn(Object *trencoder_obj, uint64_t pc) trencoder_send_message_smem(trencoder, msg, msg_size); } +static uint64_t rv_ntrace_encode_faddr(uint64_t pc) +{ + return pc >> 1ul; +} + +void trencoder_send_prog_trace_sync(Object *trencoder_obj, uint64_t pc) +{ + TraceEncoder *trencoder = TRACE_ENCODER(trencoder_obj); + g_autofree uint8_t *msg = g_malloc0(TRACE_MSG_MAX_SIZE); + uint8_t msg_size; + + uint64_t faddr = rv_ntrace_encode_faddr(pc); + + g_assert(trencoder->ntrace); + + msg_size = rv_ntrace_gen_encoded_prog_trace_sync_msg(msg, faddr); + + trencoder_send_message_smem(trencoder, msg, msg_size); +} + + void trencoder_trace_trap_insn(Object *trencoder_obj, uint64_t pc, uint32_t ecause, bool is_interrupt, diff --git a/hw/riscv/trace-encoder.h b/hw/riscv/trace-encoder.h index fed0ef9a48..96324d2b9a 100644 --- a/hw/riscv/trace-encoder.h +++ b/hw/riscv/trace-encoder.h @@ -53,6 +53,7 @@ struct TraceEncoder { OBJECT_DECLARE_SIMPLE_TYPE(TraceEncoder, TRACE_ENCODER) void trencoder_set_first_trace_insn(Object *trencoder_obj, uint64_t pc); +void trencoder_send_prog_trace_sync(Object *trencoder_obj, uint64_t pc); void trencoder_trace_trap_insn(Object *trencoder_obj, uint64_t pc, uint32_t ecause, bool is_interrupt, -- 2.43.0
