diff --git a/sys/boot/i386/libfirewire/firewire.c b/sys/boot/i386/libfirewire/firewire.c
index 5edb67a4ecbe..8191a63d8b3d 100644
--- a/sys/boot/i386/libfirewire/firewire.c
+++ b/sys/boot/i386/libfirewire/firewire.c
@@ -233,7 +233,8 @@ fw_init_crom(struct fwohci_softc *sc)
 	src->businfo.cyc_clk_acc = 100;
 	src->businfo.max_rec = sc->maxrec;
 	src->businfo.max_rom = MAXROM_4;
-	src->businfo.generation = 1;
+#define FW_GENERATION_CHANGEABLE 2
+	src->businfo.generation = FW_GENERATION_CHANGEABLE;
 	src->businfo.link_spd = sc->speed;
 
 	src->businfo.eui64.hi = sc->eui.hi;
@@ -313,11 +314,14 @@ fw_crom(struct fwohci_softc *sc)
 	src = &sc->crom_src_buf->src;
 	crom_load(src, (uint32_t *)newrom, CROMSIZE);
 	if (bcmp(newrom, sc->config_rom, CROMSIZE) != 0) {
-		/* bump generation and reload */
-		src->businfo.generation ++;
-		/* generation must be between 0x2 and 0xF */
+		/* Bump generation and reload. */
+		src->businfo.generation++;
+
+		/* Handle generation count wraps. */
 		if (src->businfo.generation < 2)
-			src->businfo.generation ++;
+			src->businfo.generation = 2;
+
+		/* Recalculate CRC to account for generation change. */
 		crom_load(src, (uint32_t *)newrom, CROMSIZE);
 		bcopy(newrom, (void *)sc->config_rom, CROMSIZE);
 	}