Index: kern_cpu.c
===================================================================
RCS file: /home/ncvs/src/sys/kern/kern_cpu.c,v
retrieving revision 1.28
diff -u -r1.28 kern_cpu.c
--- kern_cpu.c	30 Oct 2007 22:18:08 -0000	1.28
+++ kern_cpu.c	13 Jan 2008 01:38:24 -0000
@@ -606,6 +606,17 @@
 	/* Finally, output the list of levels. */
 	i = 0;
 	TAILQ_FOREACH(lev, &sc->all_levels, link) {
+		/*
+		 * Skip levels that are too close in frequency to the
+		 * previous levels.  Some systems report bogus duplicate
+		 * settings (i.e., for acpi_perf).
+		 */
+		if (i > 0 && CPUFREQ_CMP(lev->total_set.freq,
+		    levels[i - 1].total_set.freq)) {
+			sc->all_count--;
+			continue;
+		}
+
 		/* Skip levels that have a frequency that is too low. */
 		if (lev->total_set.freq < cf_lowest_freq) {
 			sc->all_count--;