From: Bin Meng <bmeng...@gmail.com>
At present when input clock is disabled, any character transmitted
to tx fifo can still show on the serial line, which is wrong.
Fixes: b636db306e06 ("hw/char/cadence_uart: add clock support")
Signed-off-by: Bin Meng <bmeng...@gmail.com>
Reviewed-by: Alistair Francis <alistair.fran...@wdc.com>
Reviewed-by: Edgar E. Iglesias <edgar.igles...@xilinx.com>
Message-id: 20210901124521.30599-3-bmeng...@gmail.com
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
---
hw/char/cadence_uart.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/hw/char/cadence_uart.c b/hw/char/cadence_uart.c
index b4b5e8a3ee0..154be34992b 100644
--- a/hw/char/cadence_uart.c
+++ b/hw/char/cadence_uart.c
@@ -327,6 +327,11 @@ static gboolean cadence_uart_xmit(void *do_not_use,
GIOCondition cond,
static void uart_write_tx_fifo(CadenceUARTState *s, const uint8_t *buf,
int size)
{
+ /* ignore characters when unclocked or in reset */
+ if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) {
+ return;
+ }
+
if ((s->r[R_CR] & UART_CR_TX_DIS) || !(s->r[R_CR] & UART_CR_TX_EN)) {
return;
}
--
2.20.1
