2009-04-02 10:17:30 USB Mass storage BF527 Transfer Speed is low

Sudhakar GN (INDIA)

Message: 72055

Hi,

USB Mass storage is enabled in BF527 EZKIt as given below:

docs.blackfin.uclinux.org/doku.php?id=usb_peripherals#sample_configuration

Transfer Speed (Read) achieved is just 2 Mbytes/sec . We got some information from ADI tools group that 20 Mbyes/second would be possible.

Are we missing something? How to increase this transfer speed?

Regards,

Sudhakar

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2009-04-02 10:22:27 Re: USB Mass storage BF527 Transfer Speed is low

Mike Frysinger (UNITED STATES)

Message: 72057

the tests were probably done in PIO mode on 0.0 because DMA has so many anomalies associated with it

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2009-04-02 16:52:35 Re: USB Mass storage BF527 Transfer Speed is low

Robin Getz (UNITED STATES)

Message: 72075

Sudhakar:

You need to go back and check with the ADI tools group -- to see if they are talking about raw throughput (random data from a host or device) or reading something off a file system backed on a USB memory stick. ~2Mbytes/s sounds about right on a cheap USB memory stick. (did you do the same test on your desktop to see what you get there?)

docs.blackfin.uclinux.org/doku.php?id=usb_peripherals#bf54x_usb_host_performance_test

-Robin

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2009-05-11 01:52:37 Re: USB Mass storage BF527 Transfer Speed is low

Abhin Xavier (INDIA)

Message: 73931

Robin :

We tried the same command shown in

docs.blackfin.uclinux.org/doku.php?id=usb_peripherals#bf54x_usb_host_performance_test

There it shows

Test Case 2: Write Speed on FAT32

mkfs.vfat -F 32 /dev/sdb1

mount /dev/sdb1 /mnt/

time dd conv=fsync if=/dev/zero of=/mnt/100m.bin bs=1M count=100

100+0 records in

100+0 records out

real 0m 35.22s

user 0m 0.00s

sys 0m 6.44s

Result: 2.84 MB/s

But what we got is

root:/> time dd conv=fsync if=/dev/zero of=/mnt/100m.bin bs=1M count=100

100+0 records in

100+0 records out

real 3m 42.28s

user 0m 0.00s

sys 0m 8.52s

Result: 0.4 MB/s

Any idea what the problem could be??

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2009-05-11 02:29:21 Re: USB Mass storage BF527 Transfer Speed is low

Sonic Zhang (CHINA)

Message: 73932

What kind of USB memory stick do you use? The speed of different memory stick may differ a lot.

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2009-05-11 02:30:11 Re: USB Mass storage BF527 Transfer Speed is low

Sonic Zhang (CHINA)

Message: 73933

You's better try a USB hard disk instead.

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2009-05-11 08:01:52 Re: USB Mass storage BF527 Transfer Speed is low

Abhin Xavier (INDIA)

Message: 73948

Zhang:

I was using the SANdisk cruzer 1GB drive which came along with the BF527 board...i dont think its the quality of the pen drive is the issue..

also i am not able to connect external hard disks

when i connect an external hard disk the following sequence happens

root:/> usb 1-1: new high speed USB device using musb_hdrc and address 6

usb 1-1: configuration #1 chosen from 1 choice

scsi4 : SCSI emulation for USB Mass Storage devices

usb 1-1: reset high speed USB device using musb_hdrc and address 6

scsi 4:0:0:0: Device offlined - not ready after error recovery

I am using a 160 GB hard disk.

The power/access LED of the Hard disk will be blingin all the time...

Any idea whts goin wrong ??

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2009-05-11 15:32:19 Re: USB Mass storage BF527 Transfer Speed is low

Robin Getz (UNITED STATES)

Message: 73963

Abhin:

Like we have told everyone working on your team -- (I'm getting tired of repeating myself) -- there are USB issues that have no workarounds that are working in Linux today... If it works -- great -- if it doesn't -- there is little we can do in a timely manner. Sorry.

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2009-05-11 23:17:30 Re: USB Mass storage BF527 Transfer Speed is low

Sonic Zhang (CHINA)

Message: 73972

You need an external power supply for your USB harddisk.

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