Re: [PATCH v2 2/3] serial: 8250_early: prepare for dynamic BASE_BAUD

[Peter Hurley]

On 01/05/2015 08:52 AM, Vineet Gupta wrote:
> On Monday 05 January 2015 07:04 PM, Peter Hurley wrote:
>>> Also what do u think of the early IER optimization ?
>> Seems ok except the commit changelog is wrong: IER is disabled twice per _line_.
>> How did you profile it? It's ok if the answer is "seemed faster"; I'm just
>> curious.
> 
> Looking at the code yes this would be per line - but I vaguely remember seeing it
> for every char - this was when debugging a systemC model for 8250. Its been a while...
> I'd added prints in the model whenever IER would wiggle and it was just being
> written with 0's again and again when in the early polling based printing mode.

Maybe that was while running kgdb through serial8250_put_poll_char(), which is
per-char.

Regards,
Peter Hurley

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