ihex: Add support for long records to ihex2fw.c

Some drivers could do with using records like Intel HEX, but with each
record being larger than 256 bytes. This has been possible in the binary
representation (struct ihex_binrec) in the kernel since the beginning --
at least of the the current version of history. But we haven't been able
to represent that in the .HEX files which get converted to .fw files.

This adds a '-w' option to ihex2fw to make it interpret the first _two_
bytes of each line as the record length, instead of only one byte. And
adds makefile rules for %.H16->%.fw which use that.

Signed-off-by: David Woodhouse <[e-mail]>

firmware/Makefile

···
 quiet_cmd_ihex2fw  = IHEX2FW $@
       cmd_ihex2fw  = $(objtree)/$(obj)/ihex2fw $< $@
 
+quiet_cmd_h16tofw  = H16TOFW $@
+      cmd_h16tofw  = $(objtree)/$(obj)/ihex2fw -w $< $@
+
 quiet_cmd_fwbin = MK_FW   $@
       cmd_fwbin = FWNAME="$(patsubst firmware/%.gen.S,%,$@)";		     \
 		  FWSTR="$(subst /,_,$(subst .,_,$(subst -,_,$(patsubst	     \
···
 # more compact binary representation of ihex records (<linux/ihex.h>)
 $(obj)/%.fw: $(obj)/%.HEX $(obj)/ihex2fw | $(objtree)/$(obj)/$$(dir %)
 	$(call cmd,ihex2fw)
+
+# .H16 is our own modified form of Intel HEX, with 16-bit length for records.
+$(obj)/%.fw: $(obj)/%.H16 $(obj)/ihex2fw | $(objtree)/$(obj)/$$(dir %)
+	$(call cmd,h16tofw)
 
 $(firmware-dirs):
 	$(call cmd,mkdir)

firmware/ihex2fw.c

···
 #include <string.h>
 #include <unistd.h>
 #include <stdlib.h>
+#define _GNU_SOURCE
+#include <getopt.h>
+
 
 struct ihex_binrec {
 	struct ihex_binrec *next; /* not part of the real data structure */
···
 static int output_records(int outfd);
 
 static int sort_records = 0;
+static int wide_records = 0;
+
+int usage(void)
+{
+	fprintf(stderr, "ihex2fw: Convert ihex files into binary "
+		"representation for use by Linux kernel\n");
+	fprintf(stderr, "usage: ihex2fw [<options>] <src.HEX> <dst.fw>\n");
+	fprintf(stderr, "       -w: wide records (16-bit length)\n");
+	fprintf(stderr, "       -s: sort records by address\n");
+	return 1;
+}
 
 int main(int argc, char **argv)
 {
 	int infd, outfd;
 	struct stat st;
 	uint8_t *data;
+	int opt;
 
-	if (argc == 4 && !strcmp(argv[1], "-s")) {
-		sort_records = 1;
-		argc--;
-		argv++;
+	while ((opt = getopt(argc, argv, "ws")) != -1) {
+		switch (opt) {
+		case 'w':
+			wide_records = 1;
+			break;
+		case 's':
+			sort_records = 1;
+			break;
+		default:
+			return usage();
+		}
 	}
-	if (argc != 3) {
-	usage:
-		fprintf(stderr, "ihex2fw: Convert ihex files into binary "
-				"representation for use by Linux kernel\n");
-		fprintf(stderr, "usage: ihex2fw [-s] <src.HEX> <dst.fw>\n");
-		fprintf(stderr, "       -s: sort records by address\n");
-		return 1;
-	}
-	if (!strcmp(argv[1], "-"))
+
+	if (optind + 2 != argc)
+		return usage();
+
+	if (!strcmp(argv[optind], "-"))
 	    infd = 0;
 	else
-		infd = open(argv[1], O_RDONLY);
+		infd = open(argv[optind], O_RDONLY);
 	if (infd == -1) {
 		fprintf(stderr, "Failed to open source file: %s",
 			strerror(errno));
-		goto usage;
+		return usage();
 	}
 	if (fstat(infd, &st)) {
 		perror("stat");
···
 		return 1;
 	}
 
-	if (!strcmp(argv[2], "-"))
+	if (!strcmp(argv[optind+1], "-"))
 	    outfd = 1;
 	else
-		outfd = open(argv[2], O_TRUNC|O_CREAT|O_WRONLY, 0644);
+		outfd = open(argv[optind+1], O_TRUNC|O_CREAT|O_WRONLY, 0644);
 	if (outfd == -1) {
 		fprintf(stderr, "Failed to open destination file: %s",
 			strerror(errno));
-		goto usage;
+		return usage();
 	}
 	if (process_ihex(data, st.st_size))
 		return 1;
···
 	}
 
 	len = hex(data + i, &crc); i += 2;
-
+	if (wide_records) {
+		len <<= 8;
+		len += hex(data + i, &crc); i += 2;
+	}
 	record = malloc((sizeof (*record) + len + 3) & ~3);
 	if (!record) {
 		fprintf(stderr, "out of memory for records\n");