On Friday 22 January 2010, simon qian wrote: > Hi, > I plan to add trace support for Cortex-M3 to Versaloon. > Hardware is ready, first trace port is SWO configured in UART mode.
Do you have a CM3 where that doesn't require SWD support to be working? The chips I've looked at so far use the option where one pin is either TDO (for JTAG) or SWO (trace) ... and that seems to be ARM's specified preference on both mini-10pin and standard-20pin ARM JTAG/SWD headers. > Is there codes in OpenOCD available to configure the TPIU and ITM module for > SWO trace output? It's kind of waiting for SWD to work first. :) > Or implement it by add the configuration operations into config file of > STM32? For early debug, that's what I would do. Longer term, at least trace configuration should IMO be integrated into OpenOCD. Trace output should, I currently think, be managed separately ... e.g. by a GUI that can graph profiling data or display messaging in something like real-time. In case it helps ... I append a patch which I hope, someday, will be deciphering the SWO trace output. Untested. - Dave =========== CUT HERE --- contrib/itmdump.c | 441 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 441 insertions(+) --- /dev/null +++ b/contrib/itmdump.c @@ -0,0 +1,441 @@ +/* + * Copyright (C) 2010 by David Brownell + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or (at + * your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +/* + * Simple utility to parse and dump ARM Cortex-M3 SWO trace output. Once the + * mechanisms work right, this information can be used for various purposes + * including profiling (particularly easy for flat PC-sample profiles) and + * for debugging. + * + * SWO is the Single Wire Output found on some ARM cores, most notably on the + * Cortex-M3. It combines data from several sources: + * + * - Software trace (ITM): so-called "printf-style" application messaging + * using "ITM stimulus ports"; and differential timestamps. + * - Hardware trace (DWT): for profiling counters and comparator matches. + * - TPIU may issue sync packets. + * + * The trace data format is defined in Appendix E, "Debug ITM and DWT packet + * protocol", of the ARMv7-M Architecture Reference Manual (DDI 0403C). It + * is a superset of the ITM data format from the Coresight TRM. + * + * The trace data has two encodings. The working assumption is that data + * gets into this program using the UART encoding. + */ + +#include <errno.h> +#include <libgen.h> +#include <stdio.h> +#include <stdbool.h> +#include <string.h> +#include <unistd.h> + + +/* Example ITM trace word (0xWWXXYYZZ) parsing for task events, sent + * on port 31. + * WWXX: event code (0..3 pre-assigned, 4..15 reserved) + * YY: task priority + * ZZ: task number + * + * NOTE that this specific encoding could be space-optimized; and that + * trace data streams could also be history-sensitive. + */ +static void show_task(int port, unsigned data) +{ + unsigned code = data >> 16; + char buf[16]; + + switch (code) { + case 0: + strcpy(buf, "run"); + break; + case 1: + strcpy(buf, "block"); + break; + case 2: + strcpy(buf, "create"); + break; + case 3: + strcpy(buf, "destroy"); + break; + /* 4..15 reserved for other infrastructure ops */ + default: + sprintf(buf, "code %d", code); + break; + } + printf("TASK %d, pri %d: %s", + (data >> 0) & 0xff, + (data >> 8) & 0xff, + buf); +} + +static void show_reserved(FILE *f, char *label, int c) +{ + unsigned i; + + printf("%s - %#02x", label, c); + + for (i = 0; (c & 0x80) && i < 4; i++) { + c = fgetc(f); + if (c == EOF) { + printf("(ERROR %d - %s) ", errno, strerror(errno)); + break; + } + printf(" %#02x", c); + } + + printf("\n"); +} + +static bool read_varlen(FILE *f, int c, unsigned *value) +{ + unsigned size; + unsigned char buf[4]; + unsigned i; + + *value = 0; + + switch (c & 3) { + case 3: + size = 4; + break; + case 2: + size = 2; + break; + case 1: + size = 1; + break; + default: + printf("INVALID SIZE\n"); + return false; + } + + memset(buf, 0, sizeof buf); + if (fread(buf, 1, size, f) != size) + goto err; + + *value = (buf[3] << 24) + + (buf[2] << 16) + + (buf[2] << 8) + + (buf[0] << 0); + return true; + +err: + printf("(ERROR %d - %s)\n", errno, strerror(errno)); + return; +} + +static void show_hard(FILE *f, int c) +{ + unsigned type = c >> 3; + unsigned value; + unsigned size; + char *label; + + printf("DWT - ", type); + + if (!read_varlen(f, c, &value)) + return; + printf("%#x", value); + + switch (type) { + case 0: /* event counter wrapping */ + printf("overflow %s%s%s%s%s%s", + (value & (1 << 5)) ? "cyc " : "", + (value & (1 << 4)) ? "fold " : "", + (value & (1 << 3)) ? "lsu " : "", + (value & (1 << 2)) ? "slp " : "", + (value & (1 << 1)) ? "exc " : "", + (value & (1 << 0)) ? "cpi " : ""); + break; + case 1: /* exception tracing */ + switch (value >> 12) { + case 1: + label = "entry to"; + break; + case 2: + label = "exit from"; + break; + case 3: + label = "return to"; + break; + default: + label = "?"; + break; + } + printf("%s exception %d", label, value & 0x1ff); + break; + case 2: /* PC sampling */ + if (c == 0x15) + printf("PC - sleep"); + else + printf("PC - %#08x", value); + break; + case 8: /* data tracing, pc value */ + case 10: + case 12: + case 14: + printf("Data trace %d, PC %#08x", (c >> 4) & 3, value); + /* optionally followed by data value */ + break; + case 9: /* data tracing, address offset */ + case 11: + case 13: + case 15: + printf("Data trace %d, address offset %#04x", + (c >> 4) & 3, value); + /* always followed by data value */ + break; + case 16 ... 23: /* data tracing, data value */ + printf("Data trace %d, ", (c >> 4) & 3); + label = (c & 0x8) ? "write" : "read"; + switch (c & 3) { + case 3: + printf("word %s, value %#08x", label, value); + break; + case 2: + printf("halfword %s, value %#04x", label, value); + break; + case 1: + printf("byte %s, value %#02x", label, value); + break; + } + break; + default: + printf("UNDEFINED"); + break; + } + + printf("\n"); + return; +} + +/* + * Table of SWIT (SoftWare InstrumentTation) message dump formats, for + * ITM port 0..31 application data. + * + * Eventually this should be customizable; all usage is application defined. + * + * REVISIT there can be up to 256 trace ports, via "ITM Extension" packets + */ +struct { + int port; + void (*show)(int port, unsigned data); +} format[] = { + { .port = 31, .show = show_task, }, +}; + +static void show_swit(FILE *f, int c) +{ + unsigned size; + unsigned port = c >> 3; + unsigned char buf[4]; + unsigned value = 0; + unsigned i; + + printf("SWIT %u - ", port); + + if (!read_varlen(f, c, &value)) + return; + printf("%#08x", value); + + for (i = 0; i <= sizeof(format) / sizeof(format[0]); i++) { + if (format[i].port == port) { + printf(", "); + format[i].show(port, value); + break; + } + } + + printf("\n"); + return; + +err: + printf("(ERROR %d - %s)\n", errno, strerror(errno)); + return; +} + +static void show_timestamp(FILE *f, int c) +{ + unsigned counter = 0; + char *label = ""; + bool delayed = false; + + printf("TIMESTAMP - "); + + /* Format 2: header only */ + if (!(c & 0x80)) { + switch (c) { + case 0: /* sync packet -- coding error! */ + case 0x70: /* overflow -- ditto! */ + printf("ERROR - %#02x\n", c); + break; + default: + /* synchronous to ITM */ + counter = c >> 4; + goto done; + } + return; + } + + /* Format 1: one to four bytes of data too */ + switch (c) { + default: + label = ", reserved control\n"; + break; + case 0xc: + /* synchronous to ITM */ + break; + case 0xd: + label = ", timestamp delayed"; + delayed = true; + break; + case 0xe: + label = ", packet delayed"; + delayed = true; + break; + case 0xf: + label = ", packet and timetamp delayed"; + delayed = true; + break; + } + + c = fgetc(f); + if (c == EOF) + goto err; + counter = c & 0x7f; + if (!(c & 0x80)) + goto done; + + c = fgetc(f); + if (c == EOF) + goto err; + counter |= (c & 0x7f) << 7; + if (!(c & 0x80)) + goto done; + + c = fgetc(f); + if (c == EOF) + goto err; + counter |= (c & 0x7f) << 14; + if (!(c & 0x80)) + goto done; + + c = fgetc(f); + if (c == EOF) + goto err; + counter |= (c & 0x7f) << 21; + +done: + /* REVISIT should we try to convert from delta values? */ + printf("+%u%s\n", counter, label); + return; + +err: + printf("(ERROR %d - %s) ", errno, strerror(errno)); + goto done; +} + +int main(int argc, char **argv) +{ + FILE *f = stdin; + int c; + + /* parse arguments */ + while ((c = getopt(argc, argv, "f:")) != EOF) { + switch (c) { + case 'f': + /* e.g. from UART connected to /dev/ttyUSB0 */ + f = fopen(optarg, "r"); + if (!f) { + perror(optarg); + return 1; + } + break; + default: +usage: + fprintf(stderr, "usage: %s [-f input]", + basename(argv[0])); + return 1; + } + } + + /* Parse data ... records have a header then data bytes. + * NOTE: we assume getc() deals in 8-bit bytes. + */ + bool overflow = false; + + while ((c = getc(f)) != EOF) { + + /* Sync packet ... 7 zeroes, 0x80 */ + if (c == 0) { + int i; + + for (i = 0; i < 6; i++) { + c = fgetc(f); + if (c == EOF) + break; + if (c != 0) + goto bad_sync; + } + c = fgetc(f); + if (c == 0x80) { + printf("SYNC\n"); + continue; + } +bad_sync: + printf("BAD SYNC\n"); + continue; + } + + /* Overflow packet */ + if (c == 0x70) { + /* REVISIT later, report just what overflowed! + * Timestamp and SWIT can happen. Non-ITM too? + */ + overflow = true; + printf("OVERFLOW ...\n"); + continue; + } + overflow = false; + + switch (c & 0x0f) { + case 0x00: /* Timestamp */ + show_timestamp(f, c); + break; + case 0x04: /* "Reserved" */ + show_reserved(f, "RESERVED", c); + break; + case 0x08: /* ITM Extension */ + /* FIXME someday, handle these ... */ + show_reserved(f, "ITM EXT", c); + break; + case 0x0c: /* DWT Extension */ + show_reserved(f, "DWT EXT", c); + break; + default: + if (c & 4) + show_hard(f, c); + else + show_swit(f, c); + break; + } + + } + + return 0; +} _______________________________________________ Openocd-development mailing list [email protected] https://lists.berlios.de/mailman/listinfo/openocd-development
