From 6cd0f2a6cd40bdf3d06d60dab86f425285475ea0 Mon Sep 17 00:00:00 2001
From: Michal Simek <michal.simek@xilinx.com>
Date: Wed, 3 Feb 2016 15:16:51 +0100
Subject: [PATCH] serial: zynq: Change logic in putc
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Sync logic with Linux kernel where TX empty flag is checked before char
is sent.
This logic is fixing problem with console on zynqmp platform.

For example:
DRAM:  2 GiB
Enabling Caches...
EL Level:	��   sdhci@ff170000: 0
Using default environment

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Moritz Fischer <moritz.fischer@ettus.com>
---
 drivers/serial/serial_zynq.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/serial/serial_zynq.c b/drivers/serial/serial_zynq.c
index e79d997cba..66d54e32ab 100644
--- a/drivers/serial/serial_zynq.c
+++ b/drivers/serial/serial_zynq.c
@@ -19,7 +19,7 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-#define ZYNQ_UART_SR_TXFULL	0x00000010 /* TX FIFO full */
+#define ZYNQ_UART_SR_TXEMPTY	(1 << 3) /* TX FIFO empty */
 #define ZYNQ_UART_SR_TXACTIVE	(1 << 11)  /* TX active */
 #define ZYNQ_UART_SR_RXEMPTY	0x00000002 /* RX FIFO empty */
 
@@ -97,7 +97,7 @@ static void _uart_zynq_serial_init(struct uart_zynq *regs)
 
 static int _uart_zynq_serial_putc(struct uart_zynq *regs, const char c)
 {
-	if (readl(&regs->channel_sts) & ZYNQ_UART_SR_TXFULL)
+	if (!(readl(&regs->channel_sts) & ZYNQ_UART_SR_TXEMPTY))
 		return -EAGAIN;
 
 	writel(c, &regs->tx_rx_fifo);
-- 
2.39.5