Does Amlogic S905X Support USB 3.0?

Despite Amlogic roadmap claiming none of the upcoming Amlogic TV box SoCs will support USB 3.0, I’ve been informed that Amlogic S905X might already support USB 3.0. So I had a check with NEXBOX A5 TV box.

First we can see dwc3 (DesignWare USB3) module is loaded:

lsmod
Module                  Size  Used by
dwc3                   17981  0 
mali                  233433  36

lsmod

Module Size Used by

dwc3 17981 0

mali 233433 36

then this happens when I connect a USB 3.0 hard drive or flash drive:

[ 4812.378262@0] usb 1-2: new high-speed USB device number 7 using xhci-hcd
[ 4812.798557@0] usb-storage 1-2:1.0: USB Mass Storage device detected
[ 4812.801416@0] scsi1 : usb-storage 1-2:1.0

[ 4812.378262@0] usb 1-2: new high-speed USB device number 7 using xhci-hcd

[ 4812.798557@0] usb-storage 1-2:1.0: USB Mass Storage device detected

[ 4812.801416@0] scsi1 : usb-storage 1-2:1.0

The important point here is xhci, which stands for “eXtensible Host Controller Interface” and supports USB 1.x to USB 3.x devices.

The next step is to check performance, but since S905X is running Android 6.0, I went through permission issues with both A1SD bench and Disk Speed apps, so I reverted to using dd to read a large file to /dev/null.

Result with USB 3.0 hard drive:

dd if=Sintel-Bluray.iso of=/dev/null bs=1024*1024*32                           
47+1 records in
47+1 records out
1593180160 bytes transferred in 42.681 secs (37327620 bytes/sec)

dd if=Sintel-Bluray.iso of=/dev/null bs=1024*1024*32

47+1 records in

47+1 records out

1593180160 bytes transferred in 42.681 secs (37327620 bytes/sec)

That’s about 35.6 MB/s, which would be an excellent USB 2.0 transfer rate, but not quite USB 3.0 material, and the drive can achieve around 100MB/s in a Linux computer with USB 3.0 port.

Results with USB 3.0 flash drive:

dd if=Sintel-Bluray.iso of=/dev/null bs=1024*1024*32                           
47+1 records in
47+1 records out
1593180160 bytes transferred in 72.088 secs (22100490 bytes/sec)

dd if=Sintel-Bluray.iso of=/dev/null bs=1024*1024*32

47+1 records in

47+1 records out

1593180160 bytes transferred in 72.088 secs (22100490 bytes/sec)

That’s 21.07 MB/s, which is quite typical for USB 2.0 transfers.

So while a USB 3.0 driver is loaded into memory, those results don’t quite point to much better performance. [Update: After further study, the speed is also limited to 480 Mbps (USB 2.0 speed), see comments below]

Jean-Luc Aufranc (CNXSoft)

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.