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From: "Christian Magnusson" <christian.magnusson@runaware.com>
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Date: Tue, 9 Mar 2004 09:36:20 +0100
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Subject: patch for writeable mtd-partitions.
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Hi again...

(I sent this to uclinux-dev mailing list before, but I guess this list
should have a copy of it too.)

I added support for write-able mtd-partitions at minor boundary. The diff
could be found at this link:

http://home.mag.cx/uclinux/patches/linux-2.6.x/mtdpart.diff

(I've been working with the linux-2.6.2-uc0 kernel in
uClinux-dist-20040218.tar.gz)

Could somebody review the patch and add it to the CVS?  It works for me, but
I guess somebody have comments on optimisation and coding style etc.


The patch will fix the problem when you have a flash with different erase
block sizes. In my case I have two AM79LV004T roms with This layout:

"Image"  0x000000-0x0F8000
"Config" 0x0F8000-0x100000

The erase size for the flash is:
0x000000-0x0E0000  (7 blocks a 0x20000)
0x0E0000-0x0F0000  (1 block  a 0x10000)
0x0F0000-0x0F8000  (2 blocks a 0x04000)
0x0F8000-0x100000  (1 block  a 0x08000)

Before it was impossible to get a writeable partition for "Image" since it
detected the erase size to 0x20000, and 0x0F8000%0x20000 is NOT zero.
With the patch a partition could start/end at 0x0F4000 too which wasn't
possible before.

/Christian