+#if CONFIG_POST & CONFIG_SYS_POST_UART
+# define LOOP(x) x
+#else
+# define LOOP(x)
+#endif
+
+#if BFIN_UART_HW_VER < 4
+
+LOOP(
+static void uart_loop(uint32_t uart_base, int state)
+{
+ u16 mcr;
+
+ /* Drain the TX fifo first so bytes don't come back */
+ while (!(uart_lsr_read(uart_base) & TEMT))
+ continue;
+
+ mcr = bfin_read(&pUART->mcr);
+ if (state)
+ mcr |= LOOP_ENA | MRTS;
+ else
+ mcr &= ~(LOOP_ENA | MRTS);
+ bfin_write(&pUART->mcr, mcr);
+}
+)
+
+#else
+
+LOOP(
+static void uart_loop(uint32_t uart_base, int state)
+{
+ u32 control;
+
+ /* Drain the TX fifo first so bytes don't come back */
+ while (!(uart_lsr_read(uart_base) & TEMT))
+ continue;
+
+ control = bfin_read(&pUART->control);
+ if (state)
+ control |= LOOP_ENA | MRTS;
+ else
+ control &= ~(LOOP_ENA | MRTS);
+ bfin_write(&pUART->control, control);
+}
+)
+
+#endif
+