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Subject: Re: [PATCH] Stop pmac_zilog from abusing 8250's device numbers.
From: David Miller <davem@davemloft.net>
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From: Russell King <rmk+lkml@arm.linux.org.uk>
Date: Wed, 4 Apr 2007 10:00:16 +0100

> On Wed, Apr 04, 2007 at 01:43:30AM -0700, David Miller wrote:
> > Well the "bad hack" we use on sparc gives usable serial ports,
> > properly ordered and using /dev/ttyS0, with a proper matching
> > console selection.
> 
> Well yes, but it seems to have code in the architecture's early
> command line parsing to parse the "console=" argument to set this
> magical "serial_console" variable.
> 
> Is this an approach you recommend for all architectures?

The platform should use whatever is appropriate, and matches
firmware/bios/whatever conventions, to determine this stuff.

On Sparc you get an openfirmware environment variable called
"output-device" that can point to a framebuffer or serial
console device.

The user can override this on the kernel command line, of course, and
what they ask for will get translated properly.