Re: [PATCH v2 2/3] serial: 8250: Store whether fifo device is enabled

From: Andy Shevchenko
Date: Tue Apr 16 2024 - 14:55:50 EST


On Tue, Apr 16, 2024 at 06:29:56PM +0000, Michael Pratt wrote:
> Currently, there are 7 checks for whether to enable
> the internal fifo device of a 8250/16550 type uart.
>
> Instead of checking all 7 values again whenever
> we need to know whether we have the fifo device enabled,
> store the result as a struct member of uart_8250_port.
>
> This can, for example, lessen the amount
> of calculations done during a write operation.

..

> @@ -3392,6 +3392,8 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,

> + up->fifo_enable = use_fifo;

This seems incorrect / not the only one place to assign this. What if the
console not enabled at compile time? What if it's not enabled at boot time?

--
With Best Regards,
Andy Shevchenko