Do not transmit characters when UART or transmitter are disabled.
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
---
hw/char/pl011.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/hw/char/pl011.c b/hw/char/pl011.c
index c55ef41fbf..30bedeac15 100644
--- a/hw/char/pl011.c
+++ b/hw/char/pl011.c
@@ -76,6 +76,10 @@ DeviceState *pl011_create(hwaddr addr, qemu_irq irq, Chardev
*chr)
#define LCR_FEN (1 << 4)
#define LCR_BRK (1 << 0)
+/* Control Register, UARTCR */
+#define CR_TXE (1 << 8)
+#define CR_UARTEN (1 << 0)
+
static const unsigned char pl011_id_arm[8] =
{ 0x11, 0x10, 0x14, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
static const unsigned char pl011_id_luminary[8] =
@@ -151,7 +155,9 @@ static inline void pl011_reset_tx_fifo(PL011State *s)
static void pl011_write_tx(PL011State *s, const uint8_t *buf, int length)
{
- /* ??? Check if transmitter is enabled. */
+ if (!(s->cr & (CR_UARTEN | CR_TXE))) {
+ return;
+ }
/* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks */
--
2.38.1
