[Solved]Timing issue when we use SPANSION 8MB Flash

[李威震]

Dear all:
I find a patch for mtd driver (drivers/mtd/chips/cfi_cmdset_0002.c) of linux-2.4.22
http://mailman.uclinux.org/pipermail/uclinux-dev/2004-May/026433.html
which add "write_buffer" function for amd flash.
It solved my problem.
This feature is already in mtd driver of linux-2.6.
But for some reason, we still use customized linux-2.4 kernel.

-----Original Message-----
From: Boby S Pullamkottu [mailto:bobys at tataelxsi.co.in]
Sent: Friday, January 26, 2007 6:19 PM
To: 李威震; linux-mtd at lists.infradead.org
Subject: Re: Timing issue when we use SPANSION 8MB Flash


Hello,
I guess this is because of garbage collector thread. Since the sector size is 128KB, you have only few sectors left free (unused) while copying 4.5 MB file.This triggers garbage collector thread to run continuously to make free sectors.

Only way is to have more flash size or have root file system with more free space. (Keeping only required binaries and files in the root FS gives more free space and this prevent garbage collection in the very beginning).


---- Original message ----
>Date: Fri, 26 Jan 2007 15:09:01 +0800
>From: 李威震 <weichen.lee at askey.com.tw>  
>Subject: Timing issue when we use SPANSION 8MB Flash  
>To: <linux-mtd at lists.infradead.org>
>
>hi,
>I find the discussion with the same subject in the past,
>http://www.infradead.org/pipermail/linux-mtd/2005-October/013996.html
>but it's without worth suggestion.
>Now we have more the same situation.
>We use linux kernel 2.4.19-rmk4-2.17 which is chipset vendor provided.
>The target board arch is arm920t. There is  SPANSION 8MB Nor Flash
>(S29GL064A90TFIR7) on the board.
>we use root file system with jffs2 format on the nor flash.
>The problem is copying the file to /dev/mtd# or the file system will take 
>very long time(around 15 min for 4.5 MB). 
>any suggestion for this iussue?
>
>Best Regards
>weichen.lee
>E-mail:weichen.lee at askey.com.tw 
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