[PATCH 0/2] Improve GTA02 NAND read performance by 41%

Holger Freyther zecke at openmoko.org
Tue Oct 21 20:04:00 CEST 2008


On Tuesday 21 October 2008 11:22:31 Harald Welte wrote:

> I'm really lost here, don't know what else to do.  I'll get some profiles
> on a soft-ECC and on a non-irq-based-NAND kernel to compare the results and
> see if they also show this 'artefact'.  Maybe 'top' is actually wrong?  Any
> ideas?

@oprofile: You could catch Richard on irc, IIRC he did work on oprofile for 
ARM and XScale and might know if some thing are not accounted because of 
missing hooks.

@nand read:
	- If we can not read faster, we can read fewer? The untested ideas are 
attached. On S3C2442 there is a 2nd ECC hardware register bank, by setting 
the ecc.size higher we might kill half of your read call's (if we can 
actually read 512 byte at a time...) and the second ECC register is actually 
doing something.

	- Or just disable ECC this should make us read more data at once 
(mtd->writesize)

maybe this sounds stupid or you already have tested these...

nice that you work on this
	z.
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