Add compiler/decompiler for lightbar bytecode programs.

BUG=none
BRANCH=ToT
TEST=manual

  make BOARD=samus
  for i in extra/lightbar/programs/[g-z]*.bin; do
    ./build/samus/util/lbcc -d $i /tmp/x.lbs
    ./build/samus/util/lbcc /tmp/x.lbs /tmp/x.bin
    cmp $i /tmp/x.bin
  done

Change-Id: I86c014c425e917ecafadd1c6845fcf2e5b4edbb7
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/220244

1 files changed, 602 insertions, 0 deletions

diff --git a/util/lbcc.c b/util/lbcc.c
new file mode 100644
index 0000000000..6fdefed927
--- /dev/null
+++ b/util/lbcc.c
@@ -0,0 +1,602 @@
+/*
+ * Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "compile_time_macros.h"
+#include "ec_commands.h"
+#include "lb_common.h"
+#include "lightbar.h"
+
+static const char usage[] =
+	"\n"
+	"Usage:  %s [OPTIONS] [INFILE [OUTFILE]]\n"
+	"\n"
+	"This compiles or decompiles the lightbar programmable bytecode.\n"
+	"\n"
+	"Options:\n"
+	"  -d         Decode binary to ascii\n"
+	"  -v         Decode output should be verbose\n"
+	"\n";
+
+/* globals */
+static int hit_errors;
+static int opt_verbose;
+static int is_jump_target[LB_PROG_LEN];		/* does program jump here? */
+static int is_instruction[LB_PROG_LEN];		/* instruction or operand? */
+static char *label[LB_PROG_LEN];		/* labels we've seen */
+static char *reloc_label[LB_PROG_LEN];		/* put label target here */
+
+static void Error(const char *format, ...)
+{
+	va_list ap;
+	va_start(ap, format);
+	fprintf(stderr, "ERROR: ");
+	vfprintf(stderr, format, ap);
+	va_end(ap);
+	hit_errors++;
+}
+
+static void Warning(const char *format, ...)
+{
+	va_list ap;
+	va_start(ap, format);
+	fprintf(stderr, "Warning: ");
+	vfprintf(stderr, format, ap);
+	va_end(ap);
+}
+
+/* The longest line should have a label, an opcode, and the max operands */
+#define MAX_WORDS (2 + LB_PROG_MAX_OPERANDS)
+
+struct safe_lb_program {
+	struct lb_program p;
+	uint8_t zeros[LB_PROG_MAX_OPERANDS];
+} __packed;
+
+#define OP(X) X
+#include "lightbar_opcode_list.h"
+enum lightbyte_opcode {
+	LIGHTBAR_OPCODE_TABLE
+	HALT,
+	MAX_OPCODE
+};
+#undef OP
+
+static const char const *opcode_sym[] = {
+	"jump", "wait", "bright", "color",
+	"step", "ramp.1", "cycle.1", "cycle",
+	"halt",
+};
+BUILD_ASSERT(ARRAY_SIZE(opcode_sym) == MAX_OPCODE);
+
+static const char const *control_sym[] = {
+	"beg", "end", "phase", "<invalid>"
+};
+static const char const *color_sym[] = {
+	"r", "g", "b", "rgb"
+};
+
+static void read_binary(FILE *fp, struct safe_lb_program *prog)
+{
+	int got;
+
+	memset(prog, 0, sizeof(*prog));
+
+	/* Read up to one more byte than we need, so we know if it's too big */
+	got = fread(prog->p.data, 1, LB_PROG_LEN + 1, fp);
+	if (got < 1) {
+		Error("Unable to read any input: ");
+		if (feof(fp))
+			fprintf(stderr, "EOF\n");
+		else if (ferror(fp))
+			fprintf(stderr, "%s\n", strerror(errno));
+		else
+			fprintf(stderr, "no idea why.\n");
+	} else if (got > LB_PROG_LEN) {
+		Warning("Truncating input at %d bytes\n", LB_PROG_LEN);
+		prog->zeros[0] = 0;
+		got = LB_PROG_LEN;
+	} else {
+		prog->p.size = got;
+	}
+}
+
+/* Returns number of operands required by an opcode */
+static int num_operands(uint8_t cmd, uint8_t *arg)
+{
+	int operands = 0;
+
+	switch (cmd) {
+	case JUMP:
+	case SET_BRIGHTNESS:
+		operands = 1;
+		break;
+
+	case DELAY:
+	case SET_DELAY_TIME:
+		operands = 4;
+		break;
+
+	case SET_COLOR:
+		if ((arg[0] & 0x03) == LB_COL_ALL)
+			operands = 4;
+		else
+			operands = 2;
+		break;
+
+	default:
+		break;
+	}
+	return operands;
+}
+
+static uint32_t val32(uint8_t *ptr)
+{
+	uint32_t val;
+	val = (ptr[0] << 24) | (ptr[1] << 16) | (ptr[2] << 8) | ptr[3];
+	return val;
+}
+
+/* returns number of operands consumed */
+static int print_op(FILE *fp, uint8_t addr, uint8_t cmd, uint8_t *arg)
+{
+	uint8_t led, color, control;
+	int i, operands;
+
+	operands = num_operands(cmd, arg);
+
+	/* assume valid instruction for now */
+	is_instruction[addr] = 1;
+
+	if (opt_verbose) {
+		fprintf(fp, "%02x:  %02x", addr, cmd);
+		for (i = 0; i < LB_PROG_MAX_OPERANDS; i++)
+			if (i < operands)
+				fprintf(fp, " %02x", arg[i]);
+			else
+				fprintf(fp, "   ");
+		fprintf(fp, "\t");
+	}
+	if (is_jump_target[addr])
+		fprintf(fp, "L00%02x:", addr);
+	fprintf(fp, "\t");
+
+	if (cmd < MAX_OPCODE)
+		fprintf(fp, "%s", opcode_sym[cmd]);
+
+	switch (cmd) {
+	case JUMP:
+		fprintf(fp, "\tL00%02x\n", arg[0]);
+		break;
+	case DELAY:
+	case SET_DELAY_TIME:
+		fprintf(fp, "\t%d\n", val32(arg));
+		break;
+	case SET_BRIGHTNESS:
+		fprintf(fp, "\t%d\n", arg[0]);
+		break;
+	case SET_COLOR:
+		led = arg[0] >> 4;
+		control = (arg[0] >> 2) & 0x03;
+		color = arg[0] & 0x03;
+		fprintf(fp, "\t");
+		if (led >= NUM_LEDS)
+			fprintf(fp, "all");
+		else
+			fprintf(fp, "%d", led);
+		fprintf(fp, ".%s", control_sym[control]);
+		fprintf(fp, ".%s", color_sym[color]);
+		if (color == LB_COL_ALL)
+			fprintf(fp, "\t0x%02x 0x%02x 0x%02x\n",
+				arg[1], arg[2], arg[3]);
+		else
+			fprintf(fp, "\t0x%02x\n", arg[1]);
+		break;
+	case RAMP_ONCE:
+	case CYCLE_ONCE:
+	case CYCLE:
+	case HALT:
+		fprintf(fp, "\n");
+		break;
+	default:
+		fprintf(fp, "-- invalid opcode 0x%02x --\n", cmd);
+		is_instruction[addr] = 0;
+		hit_errors++;
+	}
+
+	return operands;
+}
+
+static void disassemble_prog(FILE *fp, struct safe_lb_program *prog)
+{
+	int i;
+	uint8_t *ptr, targ;
+
+	/* Scan the program once to identify all the jump targets,
+	 * so we can print the labels when we encounter them. */
+	for (i = 0; i < prog->p.size; i++) {
+		ptr = &prog->p.data[i];
+		if (ptr[0] == JUMP) {
+			targ = ptr[1];
+			is_jump_target[targ] = 1;
+		}
+		i += num_operands(*ptr, ptr + 1);
+	}
+
+	/* Now disassemble */
+	for (i = 0; i < prog->p.size; i++) {
+		ptr = &prog->p.data[i];
+		i += print_op(fp, i, *ptr, ptr + 1);
+	}
+
+	/* Finally, make sure the program doesn't jump to any location other
+	 * than a valid instruction */
+	for (i = 0; i < LB_PROG_LEN; i++)
+		if (is_jump_target[i] && !is_instruction[i]) {
+			Warning("program jumps to 0x%02x, "
+				"which is not a valid instruction\n", i);
+		}
+}
+
+/* We'll split each line into an array of these. */
+struct parse_s {
+	char *word;
+	int is_num;
+	uint32_t val;
+};
+
+/* Fills in struct, returns number of words found. Note that pointers are only
+ * copied. The strings they point to are not duplicated.  */
+static int split_line(char *buf, char *delim, struct parse_s *elt, int max)
+{
+	char *w, *ptr, *buf_savetok;
+	int i;
+	char *e = 0;
+
+	memset(elt, 0, max * sizeof(*elt));
+
+	for (ptr = buf, i = 0;
+	     i < max && (w = strtok_r(ptr, delim, &buf_savetok)) != 0;
+	     ptr = 0, i++) {
+		elt[i].word = w;
+		elt[i].val = (uint32_t)strtoul(w, &e, 0);
+		if (!e || !*e)
+			elt[i].is_num = 1;
+
+	}
+
+	return i;
+}
+
+/* Decode color arg. Return 0 if bogus, number of additional args if okay. */
+static int is_color_arg(char *buf, uint32_t *valp)
+{
+	struct parse_s token[MAX_WORDS];
+	uint8_t led, control, color, val;
+	int  i;
+	int rv = 1;
+
+	if (!buf)
+		return 0;
+
+	/* There should be three terms, separated with '.' */
+	i = split_line(buf, ".,", token, MAX_WORDS);
+	if (i != 3)
+		return 0;
+
+	if (!strcmp("all", token[0].word)) {
+		led  = NUM_LEDS;
+	} else if (token[0].is_num) {
+		led = token[0].val;
+	} else {
+		Error("Invalid LED \"%s\"\n", token[0].word);
+		return 0;
+	}
+
+	for (i = 0; i < LB_CONT_MAX; i++)
+		if (!strcmp(token[1].word, control_sym[i])) {
+			control = i;
+			break;
+		}
+	if (i >= LB_CONT_MAX)
+		return 0;
+
+	for (i = 0; i < ARRAY_SIZE(color_sym); i++)
+		if (!strcmp(token[2].word, color_sym[i])) {
+			color = i;
+			break;
+		}
+	if (i >= ARRAY_SIZE(color_sym))
+		return 0;
+
+
+	val = ((led & 0xF) << 4) | ((control & 0x3) << 2) | (color & 0x3);
+
+	*valp = val;
+	if (color == LB_COL_ALL)
+		rv = 3;
+
+	return rv;
+}
+
+static void fixup_symbols(struct safe_lb_program *prog)
+{
+	int i, j;
+
+	for (i = 0; i < LB_PROG_LEN; i++) {
+		if (reloc_label[i]) {
+			/* Looking for reloc label */
+			for (j = 0; j < LB_PROG_LEN; j++) {
+				if (label[j] && !strcmp(label[j],
+							reloc_label[i])) {
+					prog->p.data[i] = j;
+					break;
+				}
+			}
+			if (j >= LB_PROG_LEN)
+				Error("Can't find label %s from line %d\n", j);
+		}
+	}
+}
+
+
+static void compile(FILE *fp, struct safe_lb_program *prog)
+{
+	char buf[128];
+	struct parse_s token[MAX_WORDS];
+	char *s;
+	int line = 0, chopping = 0;
+	uint8_t addr = 0;
+	int opcode;
+	int wnum, wordcnt;
+	int i;
+
+	while (fgets(buf, sizeof(buf), fp)) {
+
+		/* We truncate lines that are too long */
+		s = strchr(buf, '\n');
+		if (chopping) {
+			if (s)
+				chopping = 0;
+			continue;
+		}
+
+		/* Got something to look at */
+		line++;
+		if (!s) {
+			chopping = 1;
+			Warning("truncating line %d\n", line);
+		}
+
+		/* Ignore comments */
+		s = strchr(buf, '#');
+		if (s)
+			*s = '\0';
+
+		wordcnt = split_line(buf, " \t\n", token, MAX_WORDS);
+		if (!wordcnt)
+			continue;
+
+		wnum = 0;
+
+		/* A label must be the first word, ends with a ':' (no spaces
+		 * before it), and doesn't start with a ':' */
+		s = strchr(token[0].word, ':');
+		if (s && s[1] == '\0' && s != token[0].word) {
+			*s = '\0';
+			label[addr] = strdup(token[0].word);
+			wnum++;
+		}
+
+		/* How about an opcode? */
+		for (opcode = 0; opcode < MAX_OPCODE; opcode++)
+			if (!strcasecmp(token[wnum].word, opcode_sym[opcode]))
+				break;
+
+		if (opcode >= MAX_OPCODE) {
+			Error("Unrecognized opcode \"%s\""
+			      " at line %d\n", token[wnum].word, line);
+			continue;
+		}
+
+		/* Do we even have a place to write this opcode? */
+		if (addr >= LB_PROG_LEN) {
+			Error("out of program space at line %d\n", line);
+			break;
+		}
+
+		/* Got an opcode. Save it! */
+		prog->p.data[addr++] = opcode;
+		wnum++;
+
+		/* Now we need operands. */
+		switch (opcode) {
+		case JUMP:
+			/* a label */
+			if (token[wnum].word)
+				reloc_label[addr++] = strdup(token[wnum].word);
+			else
+				Error("Missing jump target at line %d\n", line);
+			break;
+
+		case SET_BRIGHTNESS:
+			/* one 8-bit arg */
+			if (token[wnum].is_num)
+				prog->p.data[addr++] = token[wnum].val;
+			else
+				Error("Missing/invalid arg at line %d\n", line);
+			break;
+
+		case DELAY:
+		case SET_DELAY_TIME:
+			/* one 32-bit arg */
+			if (token[wnum].is_num) {
+				prog->p.data[addr++] =
+					(token[wnum].val >> 24) & 0xff;
+				prog->p.data[addr++] =
+					(token[wnum].val >> 16) & 0xff;
+				prog->p.data[addr++] =
+					(token[wnum].val >> 8) & 0xff;
+				prog->p.data[addr++] =
+					token[wnum].val & 0xff;
+			} else {
+				Error("Missing/invalid arg at line %d\n", line);
+			}
+			break;
+
+		case SET_COLOR:
+			/* one magic word, then one or three more 8-bit args */
+			i = is_color_arg(token[wnum].word, &token[wnum].val);
+			if (!i) {
+				Error("Missing/invalid arg at line %d\n", line);
+				break;
+			}
+			/* save the magic number */
+			prog->p.data[addr++] = token[wnum++].val;
+			while (i--) {
+				/* and the others */
+				if (token[wnum].is_num) {
+					prog->p.data[addr++] =
+						token[wnum++].val;
+				} else {
+					Error("Missing/Invalid arg "
+					      "at line %d\n", line);
+					break;
+				}
+			}
+			break;
+
+		default:
+			/* No args needed */
+			break;
+		}
+
+		/* Did we run past the end? */
+		if (addr > LB_PROG_LEN) {
+			Error("out of program space at line %d\n", line);
+			break;
+		}
+	}
+	if (ferror(fp))
+		Error("problem while reading input: %s\n", strerror(errno));
+
+	if (!hit_errors)
+		fixup_symbols(prog);
+
+	if (!hit_errors)
+		prog->p.size = addr;
+
+	if (!prog->p.size)
+		Error("input file produced no output bytes\n");
+}
+
+int main(int argc, char *argv[])
+{
+	struct safe_lb_program safe_prog;
+	int opt_decode = 0;
+	int c;
+	int errorcnt = 0;
+	char *infile, *outfile;
+	FILE *ifp, *ofp;
+
+	char *progname = strrchr(argv[0], '/');
+	if (progname)
+		progname++;
+	else
+		progname = argv[0];
+
+	opterr = 0;                     /* quiet, you */
+	while ((c = getopt(argc, argv, ":dv")) != -1) {
+		switch (c) {
+		case 'd':
+			opt_decode = 1;
+			break;
+		case 'v':
+			opt_verbose = 1;
+			break;
+
+		case '?':
+			fprintf(stderr, "%s: unrecognized switch: -%c\n",
+				progname, optopt);
+			errorcnt++;
+			break;
+		case ':':
+			fprintf(stderr, "%s: missing argument to -%c\n",
+				progname, optopt);
+			errorcnt++;
+			break;
+		default:
+			errorcnt++;
+			break;
+		}
+	}
+
+	if (errorcnt) {
+		fprintf(stderr, "\nUsage:  %s [options] ...\n\n", progname);
+		exit(1);
+	}
+
+	if (argc - optind > 0) {
+		infile = argv[optind];
+		ifp = fopen(infile, "rb");
+		if (!ifp) {
+			fprintf(stderr,
+				"%s: Unable to open %s for reading: %s\n",
+				progname, infile, strerror(errno));
+			exit(1);
+		}
+	} else {
+		infile = "stdin";
+		ifp = stdin;
+	}
+
+	if (argc - optind > 1) {
+		outfile = argv[optind + 1];
+		ofp = fopen(outfile, "wb");
+		if (!ofp) {
+			fprintf(stderr,
+				"%s: Unable to open %s for writing: %s\n",
+				progname, outfile, strerror(errno));
+			exit(1);
+		}
+	} else {
+		outfile = "stdout";
+		ofp = stdout;
+	}
+
+	if (opt_decode) {
+		read_binary(ifp, &safe_prog);
+		fclose(ifp);
+		if (hit_errors)
+			return 1;
+		fprintf(ofp, "# %s\n", infile);
+		disassemble_prog(ofp, &safe_prog);
+		fclose(ofp);
+	} else {
+		memset(&safe_prog, 0, sizeof(safe_prog));
+		compile(ifp, &safe_prog);
+		fclose(ifp);
+		if (!hit_errors) {
+			if (1 != fwrite(safe_prog.p.data,
+					safe_prog.p.size, 1, ofp))
+				Error("%s: Unable to write to %s: %s\n",
+				      progname, outfile, strerror(errno));
+			else
+				fprintf(stderr, "0x%02x bytes written to %s\n",
+					safe_prog.p.size, outfile);
+		}
+		fclose(ofp);
+	}
+
+	return hit_errors;
+}