Hi Chris,
Would like to know what your thoughts are on this before I start digging
into finding a solution. I increased the current limit_us from 300ms to
600ms and I did see much fewer IO errors reported by the driver. I see
that we have routines in mmc/card/block.c that does recovery and reset,
are these already in the lines of what Matsumuro-san is suggesting?
Thanks a ton
Manoj
On Thu, 12 Jan 2012, matsumur@xxxxxxxxxxxxxxx wrote:
Hi Manoj Iyer-san,
Now, The time limit of SDXC is 500ms, but some old SD(ver.1.x) and MMC must
be take more larger time.
Regarding Ricoh SD Controller's error, I am not sure what happened.
Do you know which timing the error occurred during data transfer ?
If the error occurred when the transfer finishes, you can try to issue an
abort command. After that, execute the software reset of CMD/DAT Line. In
that case, the driver must retry the data transfer.
Thanks,
Koji Matsumuro
Ricoh Company,Ltd.
Manoj Iyer
<manoj.iyer@canon
ical.com> 宛先
Koji Matsumuro/R/RICOH@RICOH
2012/01/11 22:35 cc
件名
Ricoh SD card reader, error on r/w
lots of data.
Koji Matsumoro San,
Ricoh SD/SDHCI/MMC card readers R5C822, e823, 822 etc generate the
following error when transferring massive amounts of data.
[ 6843.012038] mmcblk0: error -110 transferring data, sector 409666, nr 2,
cmd response 0x900, card status 0xc00
[ 6843.014440] end_request: I/O error, dev mmcblk0, sector 409666
[ 6843.014448] Buffer I/O error on device mmcblk0p2, logical block 131105
[ 6843.014453] lost page write due to I/O error on mmcblk0p2
[ 6844.371388] mmcblk0: error -110 transferring data, sector 671810, nr 2,
cmd response 0x900, card status 0xc00
There are a lot of bug reports regarding this error, I am using a 16GB
SDHC card, and transferring around 1000 files ranging from sizes 800KB to
1.5MB.
Looking at the kernel code, looks like in drivers/mmc/core/core.c,
increasing the value of data timeout (limit_us to 500000), reduces the
occurrence of these errors, but does not eliminate it. I am guessing the
real problem is some place else, increasing time out only masks the real
issue. Can you please suggest some options that I can try to see why this
error might be occurring ? I tried an external USB generic SD card reader
(not Ricoh), to do the same and I do not see these errors, only happens
with pci based Ricoh card readers. Can you please point me in the right
direction to look...
Here is the code where I increased the data timeout (limit_us to 500000)
...
========== drivers/mmc/core/core.c ==========
:
:
/*
* SD cards also have an upper limit on the timeout.
*/
if (mmc_card_sd(card)) {
unsigned int timeout_us, limit_us;
timeout_us = data->timeout_ns / 1000;
if (mmc_host_clk_rate(card->host))
timeout_us += data->timeout_clks * 1000 /
(mmc_host_clk_rate(card->host) / 1000);
if (data->flags & MMC_DATA_WRITE)
/*
* The limit is really 250 ms, but that is
* insufficient for some crappy cards.
*/
limit_us = 300000;
else
limit_us = 100000;
/*
* SDHC cards always use these fixed values.
*/
if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
data->timeout_ns = limit_us * 1000;
data->timeout_clks = 0;
}
}
===============================================
Here is a test case I have been using to reproduce this issue.:
* Create 1000 files with sizes 800K ~ 1.5M
* create 4 directories on the SD card
* copy the 1000 files to each of the 4 directories simultaneously
* tail -f /var/log/kern.log
After around a minute or so, you will see a lot of errors like what I
pasted above.
Cheers
--
====================
Manoj Iyer
Ubuntu/Canonical
Hardware Enablement
====================
--
====================
Manoj Iyer
Ubuntu/Canonical
Hardware Enablement
====================
