Hi guys,

I figured out my problem.  I just reflashed the latest u-boot (dvevm 1.10.01) 
and now USB is working.  I just realized that last month, I
modified u-boot to force the ARM to run at 162Mhz instead of the stock 297Mhz; 
our hardware engineer wanted to run at a lower
speed to conserve power; we will be running at that speed in our final custom 
board.  Well, everything runs fine on my
162Mhz-version of u-boot except the USB host controller.  I looked at 
TMS320DM644x DMSoC Arm Subsystem Reference Guide
(sprue14a) and it seems like SYSCLK5 is an input to the USB PHY chip.  Since I 
reduced the ARM clock down to 162Mhz, I
think I may need to change the divider value for PLLDIV5 such that value in 
SYSCLK5 is the same as before when it was working.
Does anyone know which USB file (drivers/usb/musb ?) I need to update to 
reflect my lower ARM speed?

On a related note, is it possible to have the ARM boot up at the highest speed 
(297 Mhz), then go back to a lower speed (like 162Mhz)
after the kernel has come up?  I'm a kernel newbie so I'm not familiar with the 
kernel time management (kernel calculate jiffies based
on system clock?).

Amol/Kevin, thanks for all your help and sorry it took me this long to realize 
it was what I did to u-boot that caused the USB problems.

Regards,
Andy

----- Original Message ----
From: Amol Lad <[EMAIL PROTECTED]>
To: Andy Ngo <[EMAIL PROTECTED]>; Kevin Hilman <[EMAIL PROTECTED]>; 
[email protected]
Sent: Monday, March 19, 2007 11:35:28 PM
Subject: Re: USB port not working in GIT kernel?

Can you try removing Zheng's patch ?

----- Original Message ----
From: Andy Ngo <[EMAIL PROTECTED]>
To: Kevin Hilman <[EMAIL PROTECTED]>; Amol Lad <[EMAIL PROTECTED]>; 
[email protected]
Sent: Tuesday, March 20, 2007 12:57:00 PM
Subject: Re: USB port not working in GIT kernel?

This is driving me nuts. I don't know why it's not working; we have 2 DVEVMs 
and neither of them work.  
I had tested them with the Montavista version and they
 worked fine (after making a patch that Zheng posted).
I just couldn't get them to work with the GIT tree; I've tried Amol's config 
file and even Kelvin's config file 
(from an October 2006 post: 
http://www.mail-archive.com/[email protected]/msg00551.html).
 
I've used 4 different brands of USB thumb drives with no luck.  Here's my 
kernel:

[EMAIL PROTECTED]:~# modprobe musb_hdrc
musb_hdrc: version 2.2a/db-0.5.2,
 pio, host, debug=0
musb_hdrc: USB Host mode controller at c805e000 using PIO, IRQ 12
musb_hdrc musb_hdrc: MUSB HDRC host driver
musb_hdrc musb_hdrc: new USB bus registered, assigned bus number 1
usb usb1: configuration #1 chosen from 1 choice
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
[EMAIL PROTECTED]:~# modprobe usb_storage
SCSI subsystem initialized
Initializing USB Mass Storage driver...
usbcore: registered new interface driver usb-storage
USB Mass Storage support registered.
[EMAIL PROTECTED]:~# usb 1-1: new high speed USB device using musb_hdrc and 
address 2
usb 1-1: string descriptor 0 read error: -71
usb 1-1: string descriptor 0 read error: -110
usb 1-1: string descriptor 0 read error: -110
usb 1-1: configuration #1 chosen from 1 choice
usb 1-1: can't set config #1, error -110

The above is where usbcore is compiled as static in the kernel.  If it is 
compiled as a module, I still get the
 same
errors.  Weird thing is that if I compiled usbcore AND musb_hdrc as static, the 
board will hang after the following
message:

Uncompressing 
Linux...................................................................
..... done, booting the kernel.

I did a search and found the following post 
(http://linux.omap.com/pipermail/davinci-linux-open-source/2006-June/000262.html)
where the problem seems to be a result of a machine number discrepancy between 
u-boot and the kernel.  Hmmm..., maybe
my u-boot is out dated.  I have to check that out.

Regards,
Andy









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