omap3_beagle: Flush UART3 xmit on enable if TEMT is broken

[platform/kernel/u-boot.git] / drivers / serial / ns16550.c

diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index ed4e6b3..7f013ab 100644 (file)
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -36,10 +36,24 @@
 
 void NS16550_init(NS16550_t com_port, int baud_divisor)
 {
-#if (!defined(CONFIG_SYS_NS16550_BROKEN_TEMT))
+#if (defined(CONFIG_SPL_BUILD) && defined(CONFIG_OMAP34XX))
+       /*
+        * On some OMAP3 devices when UART3 is configured for boot mode before
+        * SPL starts only THRE bit is set. We have to empty the transmitter
+        * before initialization starts.
+        */
+       if ((serial_in(&com_port->lsr) & (UART_LSR_TEMT | UART_LSR_THRE))
+            == UART_LSR_THRE) {
+               serial_out(UART_LCR_DLAB, &com_port->lcr);
+               serial_out(baud_divisor & 0xff, &com_port->dll);
+               serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm);
+               serial_out(UART_LCRVAL, &com_port->lcr);
+               serial_out(0, &com_port->mdr1);
+       }
+#endif
+
        while (!(serial_in(&com_port->lsr) & UART_LSR_TEMT))
                ;
-#endif
 
        serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
 #if (defined(CONFIG_OMAP) && !defined(CONFIG_OMAP3_ZOOM2)) || \