From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kumar Gala <galak@codeaurora.org>
Subject: Re: [PATCH v4 2/4] arm64: dts: Add Qualcomm MSM8916 SoC and evaluation board dts
Date: Fri, 13 Mar 2015 11:43:28 -0500
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To: Mark Rutland <mark.rutland@arm.com>
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On Mar 13, 2015, at 11:25 AM, Mark Rutland <mark.rutland@arm.com> wrote=
:

> On Fri, Mar 13, 2015 at 03:50:42PM +0000, Kumar Gala wrote:
>>=20
>> On Mar 13, 2015, at 5:52 AM, Mark Rutland <mark.rutland@arm.com> wro=
te:
>>=20
>>>> +/ {
>>>> +	chosen {
>>>> +		stdout-path =3D &blsp1_uart2;
>>>> +	};
>>>=20
>>> It would be good if we had the configuration too (see
>>> Documentation/devicetree/bindings/chosen.txt), as that avoids any
>>> reliance on kernel defaults.
>>>=20
>>> You can refer to an alias, so this could be:
>>>=20
>>> aliases {
>>> 	serial0 =3D &blsp1_uart2;
>>> };
>>>=20
>>> chosen {
>>> 	stdout-path =3D "serial0:115200n8";
>>> };
>>>=20
>>> ...assuming that 115200n8 is correct for your UART, of course.
>>>=20
>>>=20
>>> [=85]
>>=20
>> Where is the code that actually handles this parsing?  I=92m not see=
 it
>> in early_init_dt_scan_chosen_serial and I don=92t believe
>> fdt_path_offset does anything special with =91:'
>=20
> Take a look at commit 7914a7c5651a5161 ("of: support passing console =
options with
> stdout-path").
>=20
> Early on of_alias_scan will find the options and in of_console_check
> we'll call add_preferred_console as appropriate. That'll be called in
> uart_add_one_port.

Ok, but earlycon dt code doesn=92t utilize this, as its setup is before=
 we unflatten the dt.

So it breaks earlycon parsing right now, I=92ll look at fixing that.

- k

--=20
Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora For=
um,
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