--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/miscutil/arfcn2ti.c	Fri Nov 27 03:53:11 2020 +0000
@@ -0,0 +1,67 @@
+/*
+ * TI's TCS211 L1 does not use standard ARFCNs internally, instead it uses
+ * its own non-standard radio_freq numbers in their place.  Other firmware
+ * components and all external interfaces do use standard ARFCNs, thus
+ * conversion functions are invoked at appropriate points in the firmware.
+ * However, L1-internal radio_freq numbers are emitted in L1 debug traces,
+ * thus anyone looking at these traces needs to be able to convert between
+ * standard ARFCNs and L1-internal radio_freq.
+ *
+ * The present utility converts a standard ARFCN into TI L1 radio_freq.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+
+main(argc, argv)
+	char **argv;
+{
+	int arfcn;
+
+	if (argc != 3) {
+usage:		fprintf(stderr, "usage: %s {eu|us} arfcn\n", argv[0]);
+		exit(1);
+	}
+	arfcn = atoi(argv[2]);
+	if (!strcmp(argv[1], "eu"))
+		arfcn2ti_eu(arfcn);
+	else if (!strcmp(argv[1], "us"))
+		arfcn2ti_us(arfcn);
+	else
+		goto usage;
+	exit(0);
+}
+
+arfcn2ti_eu(arfcn)
+{
+	if (arfcn == 0)
+		arfcn = 174;
+	else if ((arfcn >= 975) && (arfcn <= 1023))
+		arfcn -= 850;
+	else if ((arfcn >= 512) && (arfcn <= 885))
+		arfcn -= 337;
+	else if ((arfcn >= 1) && (arfcn <= 124))
+		;
+	else {
+		fprintf(stderr,
+			"error: specified ARFCN is invalid for dual-EU\n");
+		exit(1);
+	}
+	printf("%d\n", arfcn);
+}
+
+arfcn2ti_us(arfcn)
+{
+	if ((arfcn >= 128) && (arfcn <= 251))
+		arfcn -= 127;
+	else if ((arfcn >= 512) && (arfcn <= 810))
+		arfcn -= 387;
+	else {
+		fprintf(stderr,
+			"error: specified ARFCN is invalid for dual-US\n");
+		exit(1);
+	}
+	printf("%d\n", arfcn);
+}