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

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:

quoted

On Wed, Mar 07, 2012 at 06:31:31PM +0000, Arnd Bergmann wrote:

quoted

On Wednesday 07 March 2012, Jason Cooper wrote:

quoted

+       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