[PATCH 06/14] ARM: kirkwood: convert uart0 to devicetree.

[Jason]

On Wed, Mar 07, 2012 at 09:05:15PM +0100, Andrew Lunn wrote:
> On Wed, Mar 07, 2012 at 02:27:23PM -0500, Jason wrote:
> > On Wed, Mar 07, 2012 at 06:31:31PM +0000, Arnd Bergmann wrote:
> > > On Wednesday 07 March 2012, Jason Cooper wrote:
> > > > +       serial at f1012000 {
> > > > +               compatible = "ns16550a";
> > > > +               reg = <0xf1012000 0xff>;
> > > > +               reg-shift = <2>;
> > > > +               interrupts = <33>;
> > > > +               clock-frequency = <200000000>;
> > > > +       };
> > > 
> > > I just noticed that the length here should be inclusive, i.e. 0x100 not 0xff.
> > > This is different from the way we define resources in Linux.
> > 
> > Grrr.  Now I'm getting frustrated.  I'm trying to boot without
> > earlyprintk.  Evidently, something is wrong with the above, because the
> > device boots all the way up (blinky lights come on), but I get no
> > messages after the usual "Uncompressing Linux... done, booting the
> > kernel."
> 
> Hi Jason
> 
> What do you see in /proc/iomem?
> 
> You should expect:
> 
> f1012000-f10120ff : serial8250.0
>   f1012000-f101201f : serial
> f1012100-f10121ff : serial8250.1
>   f1012100-f101211f : serial
> 
> or probably just the first, if your device only has one serial port.
> 
> How about /proc/interrupts?
> 
>  33:        195  orion_irq  serial
> 
> 
> Anything like this in dmesg?
> 
> [   17.189397] Serial: 8250/16550 driver, 2 ports, IRQ sharing disabled

> [   17.210023] serial8250.0: ttyS0 at MMIO 0xf1012000 (irq = 33) is a 16550A
> [   17.624748] console [ttyS0] enabled

These two lines ^^^^ are what I'm missing.  Some probe by printk shows
it's getting all the way through tty/serial/8250/8250.c:3263
serial8250_init() okay... then nothing.

> [   17.648555] serial8250.1: ttyS1 at MMIO 0xf1012100 (irq = 34) is a 16550A
> 
> Comparing your system to the above might help you track down which
> property is wrong.
> 
> 	 Andrew