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Date: Wed, 25 Jul 2007 14:17:41 -0500
From: Scott Wood <scottwood@freescale.com>
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To: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Subject: Re: [PATCH 1/2] [IDE] Platform IDE driver
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Sergei Shtylyov wrote:
>> It doesn't buy us anything in here, but it's conceivable that someone 
>> may want to write a driver that uses a shift in the I/O accessor 
>> rather than an array of port offsets,
> 
> 
>    It wouldn't be IDE driver then, and neither it would be libata which 
> also does this another way this (despite pata_platform uses shifts too 
> -- not in the accessors, so no speed loss).

The device tree is not just for Linux.

>> equivalent of the cntlzw innstruction, and shift makes it clear that 
>> the stride must be power-of-two).  Plus, using shift is consistent 
>> with what we do on ns16550.
> 
> 
>    Why the heck should we care about the UART code taling about IDE?!

Consistency?

>    So, let me consider your argument purely speculative and invalid. ;-)

Consider it whatever you want. :-)

-Scott