On Thu, Nov 20, 2008 at 01:16:27PM -0600, Timur Tabi wrote:
> Milton Miller wrote:
>
> > Stated differently, if your routine (1) fundamently works one character
> > at a time and (2) is not interrupt driven, and (3) only supports one
> > channel, what avantage is there to an explicit hvc driver?
>
> I think it's because HVC has the ability to use HVC client drivers
> for console and TTY, but udbg does not. So if you have a udbg-only
> driver, it will cease to function when the kernel switches to the
> normal console.
>
> Perhaps it would make more sense to have the kernel continue to use udbg if
> there is no normal console driver, instead of relying on David's
> driver.
This doesn't work - the udbg console can't support a full tty driver
which is needed by userspace. Originally, I was going to extend the
udbg console so that it supported a tty backended onto the udbg
methods. Then I realised that the code I'd need to do this would be
essentially identical to hvconsole, so why duplicate it.
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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