From: Simon Schwarz <simonschwarzcor@googlemail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] Bottleneck of NAND copy speed
Date: Mon, 12 Sep 2011 13:21:10 +0200 [thread overview]
Message-ID: <4E6DEB26.4020409@gmail.com> (raw)
Hi List,
ATM I'm working on a DMA transfer from NAND to RAM of the Linux-image in
my SPL.
I?m searching for the speed bottleneck of the MT29F1G16ABBHC-ET
NAND-Flash on the devkit8000 (OMAP3).
From the timings I set on the GPMC I calced a max. speed of around 26
MiB/s. In my measurements I have a speed of around 10 MiB/s.
Here is the image of my the calculation:
https://docs.google.com/leaf?id=0B_wpO5K0MQSlYTcxMWVlOGEtY2FmYy00ODMyLWE1MTUtN2ZiZGViOWVhMzYw&hl=en_US
tcmd: The time for the initial read command
twr: time to write the address
tDn: Time for a 16bit read of Data
Does anyone has an idea where the bottleneck could be? Is my calculation
wrong?
(ecc is done parallel to the DMA transfer).
Regards
Simon
next reply other threads:[~2011-09-12 11:21 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-12 11:21 Simon Schwarz [this message]
2011-09-12 11:43 ` [U-Boot] Bottleneck of NAND copy speed Wolfgang Denk
2011-09-13 13:13 ` Simon Schwarz
2011-09-12 12:55 ` Nick Thompson
2011-09-13 13:18 ` Simon Schwarz
2011-09-13 19:53 ` Scott Wood
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