Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1256759

Re: [PATCH v2 1/2] serial: 8250_early: do not save and restore IER in write callback

From Peter Hurley <peter@hurleysoftware.com>
Newsgroups linux.kernel
Subject Re: [PATCH v2 1/2] serial: 8250_early: do not save and restore IER in write callback
Date 2015-10-27 15:00 +0100
Message-ID <qocX8-5RG-13@gated-at.bofh.it> (permalink)
References <qmYtc-65k-3@gated-at.bofh.it> <qmYtc-65k-7@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


Hi Masahiro,

On 10/24/2015 12:17 AM, Masahiro Yamada wrote:
> The IER has already been masked in early_serial8250_setup(), there is
> no reason to save and restore it every time early_serial8250_write()
> is called.
> 
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> ---
> 
>  drivers/tty/serial/8250/8250_early.c | 12 ------------
>  1 file changed, 12 deletions(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
> index 7aff3d8..559b681 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -99,20 +99,8 @@ static void __init early_serial8250_write(struct console *console,
>  {
>  	struct earlycon_device *device = console->data;
>  	struct uart_port *port = &device->port;
> -	unsigned int ier;
> -
> -	/* Save the IER and disable interrupts preserving the UUE bit */
> -	ier = serial8250_early_in(port, UART_IER);
> -	if (ier)
> -		serial8250_early_out(port, UART_IER, ier & UART_IER_UUE);
>  
>  	uart_console_write(port, s, count, serial_putc);



> -
> -	/* Wait for transmitter to become empty and restore the IER */
> -	wait_for_xmitr(port);

This wait_for_xmitr() change needs to be in patch 2/2.

Regards,
Peter Hurley

> -
> -	if (ier)
> -		serial8250_early_out(port, UART_IER, ier);
>  }
>  
>  static void __init init_port(struct earlycon_device *device)
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH v2 1/2] serial: 8250_early: do not save and restore IER in write callback Masahiro Yamada <yamada.masahiro@socionext.com> - 2015-10-24 06:20 +0200
  Re: [PATCH v2 1/2] serial: 8250_early: do not save and restore IER in  write callback Peter Hurley <peter@hurleysoftware.com> - 2015-10-27 15:00 +0100
    Re: [PATCH v2 1/2] serial: 8250_early: do not save and restore IER in  write callback Masahiro Yamada <yamada.masahiro@socionext.com> - 2015-10-28 04:30 +0100
      Re: [PATCH v2 1/2] serial: 8250_early: do not save and restore IER in  write callback Peter Hurley <peter@hurleysoftware.com> - 2015-10-28 15:40 +0100
        Re: [PATCH v2 1/2] serial: 8250_early: do not save and restore IER in  write callback Masahiro Yamada <yamada.masahiro@socionext.com> - 2015-10-29 06:30 +0100

csiph-web