Re: [PATCH] x86: Setup early console as early as possible

[H. Peter Anvin]

On 07/12/2010 01:58 AM, Pekka Enberg wrote:
> Hi Yinghai,
> 
> Yinghai Lu wrote:
>> Analyze "console=uart8250,io,0x3f8,115200n8" in
>> i386_start_kernel/x86_64_start_kernel,
>> and call setup_early_serial8250_console() to init early serial console.
>>
>> only can handle io port kind of 8250. because mmio need ioremap.
>>
>> Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
> 
> What's the purpose of this patch? Does it make my early boot I/O patch
> obsolete?
> 
>             Pekka

No, they're complementary.  Your patch serial-port enables the RM
kernel, whereas Yinghai pushes the initialization earlier in the PM kernel.

Incidentally, Yinghai: it would be possible to push even an MMIO
reference earlier by reserving a fixmap slot for the early console.  I'm
not sure if it's worth it, though.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

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