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trivial: Miscellaneous documentation typo fixes

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Fix various typos in documentation txts.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Matt LaPlante 2009-04-27 15:06:31 +02:00 • committed by Jiri Kosina
parent 19af5cdb7c
commit 19f5946001
60 changed files with 94 additions and 94 deletions
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12
Documentation/mtd/nand_ecc.txt
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@ -50,7 +50,7 @@ byte 255: bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 rp1 rp3 rp5 ... rp15
cp5 cp5 cp5 cp5 cp4 cp4 cp4 cp4
This figure represents a sector of 256 bytes.
cp is my abbreviaton for column parity, rp for row parity.
cp is my abbreviation for column parity, rp for row parity.
Let's start to explain column parity.
cp0 is the parity that belongs to all bit0, bit2, bit4, bit6.
@ -560,7 +560,7 @@ Measuring this code again showed big gain. When executing the original
linux code 1 million times, this took about 1 second on my system.
(using time to measure the performance). After this iteration I was back
to 0.075 sec. Actually I had to decide to start measuring over 10
million interations in order not to loose too much accuracy. This one
million iterations in order not to lose too much accuracy. This one
definitely seemed to be the jackpot!
There is a little bit more room for improvement though. There are three
@ -571,8 +571,8 @@ loop; This eliminates 3 statements per loop. Of course after the loop we
need to correct by adding:
rp4 ^= rp4_6;
rp6 ^= rp4_6
Furthermore there are 4 sequential assingments to rp8. This can be
encoded slightly more efficient by saving tmppar before those 4 lines
Furthermore there are 4 sequential assignments to rp8. This can be
encoded slightly more efficiently by saving tmppar before those 4 lines
and later do rp8 = rp8 ^ tmppar ^ notrp8;
(where notrp8 is the value of rp8 before those 4 lines).
Again a use of the commutative property of xor.
@ -622,7 +622,7 @@ Not a big change, but every penny counts :-)
Analysis 7
==========
Acutally this made things worse. Not very much, but I don't want to move
Actually this made things worse. Not very much, but I don't want to move
into the wrong direction. Maybe something to investigate later. Could
have to do with caching again.
@ -642,7 +642,7 @@ Analysis 8
This makes things worse. Let's stick with attempt 6 and continue from there.
Although it seems that the code within the loop cannot be optimised
further there is still room to optimize the generation of the ecc codes.
We can simply calcualate the total parity. If this is 0 then rp4 = rp5
We can simply calculate the total parity. If this is 0 then rp4 = rp5
etc. If the parity is 1, then rp4 = !rp5;
But if rp4 = rp5 we do not need rp5 etc. We can just write the even bits
in the result byte and then do something like