Author Topic: help with SD read/write speed (Read 15943 times)

albertr · « **Reply #30 on:** March 11, 2004, 06:52:17 am »

ha, I knew it was not Sharp Very nice job, indeed. Thank you for sharing this information. I\'m not sure about legal implications, I doubt Sharp would care, but SD association well might. Although, the code probably doesn\'t contain any top secret encryption or anything, you never know what those fat lawyers have in mind.

I\'d say it won\'t surprise me if the code would be leaked eventually somewhere outside of US. Regardless, please keep up good work, your changes are definitely in the right direction and much appreciated.
-albertr

abcdef · « **Reply #31 on:** March 11, 2004, 07:49:37 am »

Sounds very good. Can I try it on 5600? If not, can you compile one for 5600?

chyang · « **Reply #32 on:** March 11, 2004, 08:22:18 am »

Cool and Great!! Thank you very much for your cool module!!

Quote

I don\'t know if there any legal issues exist, so I\'ve posted the module anonimously. If you tell me that everything\'s ok, I can provide the source.
New module is 90% Sharp\'s code which was disassembled and re-assembled having some functions replaced.
Now I have approx. 50% code of the dirver converted to C.
The actual changes are:
1) Higher SPI bus freq. (I\'have no idea why original driver doesn\'t default to higher speed, although it does provide ioctl interface for changing it via /dev/sd_slotstat).
2) Different way to prefetch blocks. Original driver guarantees every eighth block to be wasted for ext2.
3) Better checksum code.
4) Original driver has hardcoded delay to wait for the card after reset. New driver attempts to detect the card multiple times increasing the delay.

agosine · « **Reply #33 on:** March 15, 2004, 10:56:07 am »

Just a question on the installation of this patch. If I rename the original file to .old and rename this to match the sharp name (sharp_mmcsd_m.o) that should work fine?

chyang · « **Reply #34 on:** March 15, 2004, 11:29:15 am »

yes, remember to reboot after you rename the module with the sharp_mmcsd_m.o

panyo · « **Reply #35 on:** March 25, 2004, 01:05:25 am »

Quote

klrussell,

gunzip the file (so it looks like mmcsd.o). Copy it to /lib/modules/2.4.18-rmk7-pxa3-embedix/kernel/drivers/block. (The 2.4.18 part may be a bit different, but you get the idea.) Remove the link to sharp_mmcsd_m.o. Make a new link:

ln -s mmcsd.o sharp_mmcsd_m.o

Reboot. I\'m sure there are better ways to do this, but it worked for me.

As a test, I copied a 23 MB backup file from CF to SD. Straight 3.13 ROM, I got 150 kB/sec. Flashing in the async kernel got me to 250 kB/sec. Installing this driver got me up to 400 kB/sec (2.5 min down to 1 min). Not bad.

Mike

I tried this, including changing the read premission on mmcsd.o with

Code: [Select]

chmod +r mmcsd.o

but when I reboot, my SD card does not appear.
I am running OZ 3.3.5
Also, is there any way to take advantage of derekp\'s kernel in OZ? I tried substituting it for zImage in the flashing process I used for OZ, but I just got a screen that said \"SHARP\" and nothing else.

tom_servo · « **Reply #36 on:** June 14, 2004, 10:17:43 am »

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Actually, I haven\'t heard any complants yet about using the async kernel. If you saw one, let me know so I can investigate.

I have had trouble with the async kernel. It doesn\'t seem to be the async part that is causing trouble though. Ever since loading that kernel, my zaurus must be rebooted between uses of the the USB network interface to the computer. If I put the Zaurus in the cradle, in a few seconds it will start to respond to pings from the computer. If I take it out of the cradle and put it back in, it does not respond to ping, even if it was suspended and resumed while out of the cradle. When re-inserted the computer ifconfig shows the usb0, but ifconfig on the zaurus only shows the â€œloâ€. I have to reboot to be able to connect to the computer again.

I re-flashed, and tried again as soon as the initial boot was finished, and had the same problem. I don\'t know if it is a problem with the kernel, my SL-5500, or incomparability with the tkcrom 1.0. I tried flashing the original tkcrom kernel, and the problem did go away, but the SD became unbearably slow again.

I would rather use the async kernel (even with this problem) because it makes SD write more then 10x faster, but it would be perfect if it didn\'t have this little problem.

Alain

Mahoro · « **Reply #37 on:** July 15, 2004, 03:28:34 pm »

After reading 3 pages of msg...I have some question...

How can I Patch that MMC/SD driver for SL5500 replacement
I am an ULTRA n00b on Zaurus, just got my 5500 from my friend.......and my friend went for a trip....

And that kernal is for 2.4.18, so it won't work on my 2.4.6 kernal is it?
Thanks

ciro · « **Reply #38 on:** July 16, 2004, 03:21:23 am »

It won't work on 2.4.6. Sorry.

jlagarde · « **Reply #39 on:** August 03, 2004, 07:03:07 pm »

Quote

It won't work on 2.4.6. Sorry.

Any way for someone to compile one for that kernel (the same kind soul who made the original mod maybe)? If someone sends me the source I can make an attempt but I can't guarantee the result, as I have little experience in that domain.

Or is the issue more involved than a simple recompile?

Cheers

albertr · « **Reply #40 on:** May 17, 2005, 10:30:33 am »

So the source code for thos module was never released?
-albertr

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Author Topic: help with SD read/write speed (Read 15943 times)