[U-Boot] ns16550: tegra: Specify debugging serial port at boot.

[Graeme Russ <graeme.russ@gmail.com>]

Hi Stephen,

On Wed, Mar 14, 2012 at 7:12 AM, Stephen Warren <swarren@wwwdotorg.org> wrote:
> On 03/08/2012 11:39 AM, Wolfgang Denk wrote:
>> Dear Stephen Warren,
>>
>> In message <4F58F5B8.6070402@wwwdotorg.org> you wrote:
>>>
>>> I noticed this patch isn't applied yet that I can find. Are there any
>>> comments on it; can it be applied? Thanks.
>>>
>>> For reference, it's in patchwork at:
>>> http://patchwork.ozlabs.org/patch/134712/
> ...
>>>> diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
>>>> @@ -62,6 +62,13 @@ void NS16550_init(NS16550_t com_port, int baud_divisor)
>>>> +#if defined(CONFIG_TEGRA2)
>>>> + ? /*
>>>> + ? ?* Put a 'D' in the scratchpad to let the kernel know which UART
>>>> + ? ?* for earlyprintk [D]ebugging.
>>>> + ? ?*/
>>>> + ? serial_out('D', &com_port->spr);
>>>> +#endif
>>
>> I don't like to see such highly architecture specific stuff in common
>> code, especially if it's such a dirty hack like this.
>
> Would it help if we moved the this code to some Tegra-specific file
> rather than the common serial port driver?

Could it be done as the last thig before jumping into the Linux kernel in
arch_preboot_os()

Regards,

Graeme