Index: sparc/cpu.c
===================================================================
RCS file: /cvsroot/src/sys/arch/sparc/sparc/cpu.c,v
retrieving revision 1.255
diff -p -u -r1.255 cpu.c
--- sparc/cpu.c	1 Oct 2019 18:00:07 -0000	1.255
+++ sparc/cpu.c	31 May 2020 19:28:37 -0000
@@ -514,6 +514,19 @@ cpu_attach(struct cpu_softc *sc, int nod
 	 */
 	if (bootmid == 0)
 		bootmid = mid;
+
+	/*
+	 * Set speeds now we've attached all CPUs.
+	 */
+	if (sparc_ncpus > 1 && sparc_ncpus == cpu_attach_count) {
+		CPU_INFO_ITERATOR n;
+		unsigned best_hz = 0;
+
+		for (CPU_INFO_FOREACH(n, cpi))
+			best_hz = MAX(cpi->hz, best_hz);
+		for (CPU_INFO_FOREACH(n, cpi))
+			cpu_topology_setspeed(cpi, cpi->hz < best_hz);
+	}
 }
 
 /*