Re: [PATCH] tty: serial: Use fifo in 8250 console driver

[Jiri Slaby]

On 25. 01. 22, 11:18, Wander Costa wrote:
> > In particular, the test is checking whether there is no interrupt
> > pending (UART_FCR_ENABLE_FIFO == UART_IIR_NO_INT). So it oscillates
> > between use_fifo and not, depending on the interrupt state of the chip.
> >
> > Could you change it into something like this:
> > --- a/drivers/tty/serial/8250/8250_port.c
> > +++ b/drivers/tty/serial/8250/8250_port.c
> > @@ -3396,7 +3396,7 @@ void serial8250_console_write(struct
> > uart_8250_port *up, const char *s,
> >
> >           use_fifo = (up->capabilities & UART_CAP_FIFO) &&
> >                   port->fifosize > 1 &&
> > -               (serial_port_in(port, UART_FCR) & UART_FCR_ENABLE_FIFO) &&
> > +               (up->fcr & UART_FCR_ENABLE_FIFO) &&
> >                   /*
> >                    * After we put a data in the fifo, the controller will
> > send
> >                    * it regardless of the CTS state. Therefore, only use fifo
>
> Indeed I made a mistake here. Independent of the reported this, this
> should be fixed.
> Jiri, do you intend to send an official patch or should I do so?

Please you send the fix after testing the fifo mode still works with 
that fix.

thanks,
--
js