On Sun, 1 Nov 2009, Justin Piszcz wrote:
On Sun, 1 Nov 2009, Matthew Dharm wrote:
On Sun, Nov 01, 2009 at 12:11:44PM -0500, Alan Stern wrote:
On Sat, 31 Oct 2009, Justin Piszcz wrote:
1. 5 minutes of usbmon output on via chipset [working]
2. 5 minutes of usbmon output on intel p55 usb chipset [ehci/not working]
To summarize the differences between the logs, the Intel controller
shows occasional instances of failed transfers like this:
ffff8802138c8500 3487005687 S Ci:2:004:0 s 81 06 2100 0000 0009 9 <
ffff8802138c8500 3487006051 C Ci:2:004:0 -32 0
while the corresponding transfers worked with the VIA controller:
ffff88020c46dd40 1774844264 S Ci:4:002:0 s 81 06 2100 0000 0009 9 <
ffff88020c46dd40 1774855248 C Ci:4:002:0 0 9 = 09211001 21012237 04
and indeed they worked in the other Intel logs (the failures appeared
to be more or less at random).
This does indeed look like a low-level hardware problem, but I'm
hesitant to blame it on the chipset. For example, the problem might
lie in the hub you've got between the UPS and the computer. I know,
this doesn't explain why everything works okay with the VIA controller.
Probably the only way to tell for sure what's really happening is by
using an expensive bus analyzer.
Have you tried bypassing that hub, and plugging the UPS directly into
the computer?
Hi,
I do not use any hubs in this environment, everything is directly attached to
the motheboard. Per Matthew (noted below) when I
mention hub I am talking about your typical USB hub one would
attach to a USB port on the board, not the integrated one on the
motherboard. Everything is directly attached from the motherboard
to each respective device.
MOBO -> UPS
MOBO -> KBD
MOBO -> etc
I think P55 chipset has an integrated hub, which is not removeable. The
only USB controller is EHCI, and that is connected directly to a hub in the
silicon which provides multiple downstream ports and does the translation
to 1.0 speeds. So the hub cannot be bypassed.
Two things to note:
1) Not all ports on that silicon are the same. Specifically, ports 1 and 9
have special properties (related to USB-based debugging). You should try
other ports (note that I count ports starting at 0).
I have tested every port on the motherboard (the 8 on the back and 4 off
of the USB headers on the motherboard):
http://home.comcast.net/~jpiszcz/20091101/ports.txt
The problem occurred on every port.
2) I noticed this article:
http://www.theregister.co.uk/2009/10/30/iphone_p55_problems/ -- this may
suggest that there are other issues with P55 chipset and USB. According to
this article, as with this reported issue, adding an external USB hub
doesn't help, but an add-in PCI USB card does. We may have to consider a
P55 issue as a possibility here.
Very interesting-- the C-state option for the CPU is on/enabled in the
BIOS, it has always remained on, I never disabled it.
Justin.
One note to add:
There is one final port on the motherboard itself near the CPU
but I would need to remove my motherboard and HSF/remove many cards etc
to be able to test that one.
All ports besides the one directly on the motherboard have been tested and
the error persists on them.
Justin.
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