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Date: Wed, 12 Dec 2007 10:40:35 -0600
From: Scott Wood <scottwood@freescale.com>
To: Anton Vorontsov <avorontsov@ru.mvista.com>
Subject: Re: [PATCH RFC 0/7] "NAND on UPM" and related patches
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On Mon, Dec 10, 2007 at 11:47:05PM +0300, Anton Vorontsov wrote:
> 5 - FSL UPM infrastructure:
> ---------------------------
> UPM address register is shared among UPMs, so we have to do
> proper locking. On the other hand, if we know that specific
> board using only one UPM we could bypass locking, and gain some
> performance win.

Not enough to be worth the complexity compared to the overhead of NAND
access -- especially in the likely case of a non-SMP build.

-Scott