Blackfin: jtag-console: fix timer usage

Reported-by: Graeme Russ <graeme.russ@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

arch/blackfin/cpu/jtag-console.c

@@ -48,11 +48,11 @@ static inline uint32_t bfin_read_emudat(void)
 static bool jtag_write_emudat(uint32_t emudat)
 {
 	static bool overflowed = false;
-	ulong timeout = get_timer(0) + CONFIG_JTAG_CONSOLE_TIMEOUT;
+	ulong timeout = get_timer(0);
 	while (bfin_read_DBGSTAT() & 0x1) {
 		if (overflowed)
 			return overflowed;
-		if (timeout < get_timer(0))
+		if (get_timer(timeout) > CONFIG_JTAG_CONSOLE_TIMEOUT)
 			overflowed = true;
 	}
 	overflowed = false;