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Subject: RE: [PATCH] booting-without-of: add Xilinx uart 16550.
Date: Fri, 15 Feb 2008 13:40:17 -0800
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From: "Stephen Neuendorffer" <stephen.neuendorffer@xilinx.com>
To: "Sergei Shtylyov" <sshtylyov@ru.mvista.com>,
	"Grant Likely" <grant.likely@secretlab.ca>
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Cc: linuxppc-dev@ozlabs.org, Pavel Kiryukhin <pkiryukhin@ru.mvista.com>
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> > Instead of attempting to come up with a generic description
> > of this, I recommend just naming it after the actual device
instance;
> > something like compatible=3D"xlnx,opb-uart16550";
>=20
>     Well, that means that we'll need a to add a code which "glues" the
chip to
> 8250.c driver... well, of_serial.c could be that glue layer if we add
to it
> the ability to recognize Xilinx UART... well, legacy_serial.c could be
taught
> that trick too...
>     Well, we could also add the new compatible, but still claim
"ns16550"
> compatibility...

This actually makes more sense to me...  I'd rather have the code set
the reg-shift than have it explicitly set in the device tree anyway.
The compatibility set should include (at the least):

      opb_uart16550_v1_00_c
      opb_uart16550_v1_00_d
      opb_uart16550_v1_00_e
      plb_uart16550_v1_00_c
      xps_uart16550_v1_00_a

I think this is somewhat independent of Sergei's arguments that generic
ns16550 devices should allow having a reg-shift set....

Steve