Re: [PATCH] serial : convert early_uart to earlycon for 8250 fix3 alias

From: Andy Whitcroft
Date: Fri Jun 22 2007 - 07:59:15 EST


Yinghai Lu wrote:
> [PATCH] serial : convert early_uart to earlycon for 8250 fix 3 alias
>
> make the console=uart,io,0x3f8,9600n8 like console=uart8250,io,0x3f8,9600
> suggested by Andy Whitcroft.
>
> Signed-off-by: Yinghai Lu <yinghai.lu@xxxxxxx>
>
> --- a/Documentation/kernel-parameters.txt 2007-06-21 10:12:48.000000000 -0700
> +++ b/Documentation/kernel-parameters.txt 2007-06-21 10:13:43.000000000 -0700
> @@ -467,16 +467,16 @@
> Documentation/networking/netconsole.txt for an
> alternative.
>
> - uart8250,io,<addr>[,options]
> - uart8250,mmio,<addr>[,options]
> + uart[8250],io,<addr>[,options]
> + uart[8250],mmio,<addr>[,options]
> Start an early, polled-mode console on the 8250/16550
> UART at the specified I/O port or MMIO address,
> switching to the matching ttyS device later. The
> options are the same as for ttyS, above.
>
> earlycon= [KNL] Output early console device and options.
> - uart8250,io,<addr>[,options]
> - uart8250,mmio,<addr>[,options]
> + uart[8250],io,<addr>[,options]
> + uart[8250],mmio,<addr>[,options]
> Start an early, polled-mode console on the 8250/16550
> UART at the specified I/O port or MMIO address.
> The options are the same as for ttyS, above.
> --- a/drivers/serial/8250_early.c 2007-06-21 10:04:25.000000000 -0700
> +++ b/drivers/serial/8250_early.c 2007-06-21 10:12:08.000000000 -0700
> @@ -210,8 +210,11 @@
> int err;
>
> options = strstr(cmdline, "uart8250,");
> - if (!options)
> - return 0;
> + if (!options) {
> + options = strstr(cmdline, "uart,");
> + if (!options)
> + return 0;
> + }

This could probabally be written as below and be a little clearer:

options = strstr(cmdline, "uart8250,");
if (!options)
options = strstr(cmdline, "uart,");
if (!options)
return 0;



>
> options = strchr(cmdline, ',') + 1;
> if ((err = early_serial8250_setup(options)) < 0)
> @@ -227,6 +230,7 @@
> struct early_serial8250_device *device = &early_device;
> struct uart_port *port = &device->port;
> int line;
> + int ret;
>
> if (!device->port.membase && !device->port.iobase)
> return -ENODEV;
> @@ -235,8 +239,13 @@
> if (line < 0)
> return -ENODEV;
>
> - return update_console_cmdline("uart", 8250,
> + ret = update_console_cmdline("uart", 8250,
> + "ttyS", line, device->options);
> + if (ret < 0)
> + ret = update_console_cmdline("uart", 0,
> "ttyS", line, device->options);
> +
> + return ret;
> }
>
> early_param("earlycon", setup_early_serial8250_console);

Other than the little nit above I have tested this on the machine which
was all upset over the change and it works like a charm.

Acked-by: Andy Whitcroft <apw@xxxxxxxxxxxx>

-apw
-
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