| Message ID | 2024010538-legged-species-457d@gregkh |
|---|---|
| State | New |
| Headers | show |
| Series | patch "serial: apbuart: fix console prompt on qemu" added to tty-next | expand |
diff --git a/drivers/tty/serial/apbuart.c b/drivers/tty/serial/apbuart.c index 716cb014c028..364599f256db 100644 --- a/drivers/tty/serial/apbuart.c +++ b/drivers/tty/serial/apbuart.c @@ -122,7 +122,7 @@ static void apbuart_tx_chars(struct uart_port *port) { u8 ch; - uart_port_tx_limited(port, ch, port->fifosize >> 1, + uart_port_tx_limited(port, ch, port->fifosize, true, UART_PUT_CHAR(port, ch), ({}));
This is a note to let you know that I've just added the patch titled serial: apbuart: fix console prompt on qemu to my tty git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git in the tty-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. From c6dcd8050fb7c2efec6946ae9c49bc186b0a7475 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg <sam@ravnborg.org> Date: Tue, 26 Dec 2023 13:16:07 +0100 Subject: serial: apbuart: fix console prompt on qemu When using a leon kernel with qemu there where no console prompt. The root cause is the handling of the fifo size in the tx part of the apbuart driver. The qemu uart driver only have a very rudimentary status handling and do not report the number of chars queued in the tx fifo in the status register. So the driver ends up with a fifo size of 1. In the tx path the fifo size is divided by 2 - resulting in a fifo size of zero. The original implementation would always try to send one char, but after the introduction of uart_port_tx_limited() the fifo size is respected even for the first char. There seems to be no good reason to divide the fifo size with two - so remove this. It looks like something copied from the original amba driver. With qemu we now have a minimum fifo size of one char, so we show the prompt. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Fixes: d11cc8c3c4b6 ("tty: serial: use uart_port_tx_limited()") Cc: Andreas Larsson <andreas@gaisler.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: <linux-serial@vger.kernel.org> Cc: <sparclinux@vger.kernel.org> Link: https://lore.kernel.org/r/20231226121607.GA2622970@ravnborg.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/tty/serial/apbuart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)