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uBoot and USB using L138F SoM
Added by Simon Edwards over 10 years ago
Hi there,
I'm using the L138F SoM on a REV B Industrial I/O board and I am trying to boot from a USB drive. uBoot is configured for USB but when I try:
usb start
All I get is:
(Re)start USB...
USB: scanning bus for devices... No USB Device found
scanning bus for storage devices... 0 Storage Device(s) found
I noticed that the +5V switch is not being turned on and I have tried again with it 'wired' to 5V (to override the switch). However the result is the same.
I've read all the relevant forum posts but I cannot see anything that solves this issue.
Please help!
Replies (9)
RE: uBoot and USB using L138F SoM - Added by Simon Edwards over 10 years ago
I forgot to say that I know that the USB port works because, once in Linux I can mount the drive OK and read/write files etc.
USB drive is plugged into J100 via an adapter cable.
RE: uBoot and USB using L138F SoM - Added by Jonathan Cormier over 10 years ago
I just tested this by first plugging the flash drive into the full size usb port J102. With no luck. Then plugged drive into J100 via adapter cable and it was discovered. See log below.
OMAP-L138/AM-1808/AM-1810 initialization passed!
Configuring 128MB mDDR
Booting TI User Boot Loader
UBL Version: 1.65:2.28.1 BuiltJul 11 2011 12:49:53
UBL Flashtype: SPI
Starting SPI Memory Copy...
Valid magicnum, 0x55424CBB, found at offset 0x00010000.
DONE
Jumping to entry point at 0xC1080000.
U-Boot 2009.11 (Jan 13 2014 - 11:14:02)
I2C: ready
DRAM: 128 MB
NAND: 256 MiB
MMC: davinci: 0
In: serial
Out: serial
Err: serial
ARM Clock : 300000000 Hz
DDR Clock : 150000000 Hz
EMIFA CLock : 100000000 Hz
DSP Clock : 300000000 Hz
ASYNC3 Clock : 150000000 Hz
Enet config : 2
MMC 0 Enable : 1
Resetting ethernet phy
Net: Ethernet PHY: GENERIC @ 0x03 [0x8]
Hit any key to stop autoboot: 0
U-Boot > usb
USB is stopped. Please issue 'usb start' first.
U-Boot > usb start
(Re)start USB...
USB: scanning bus for devices... No USB Device found
scanning bus for storage devices... 0 Storage Device(s) found
U-Boot > usb
usb - USB sub-system
Usage:
usb reset - reset (rescan) USB controller
usb stop [f] - stop USB [f]=force stop
usb tree - show USB device tree
usb info [dev] - show available USB devices
usb storage - show details of USB storage devices
usb dev [dev] - show or set current USB storage device
usb part [dev] - print partition table of one or all USB storage devices
usb read addr blk# cnt - read `cnt' blocks starting at block `blk#'
to memory address `addr'
U-Boot > usb tree
Device Tree:
0 See Interface (12 Mb/s, 0mA)
U-Boot > usb reset
(Re)start USB...
USB: scanning bus for devices... 1 USB Device(s) found
scanning bus for storage devices... 1 Storage Device(s) found
U-Boot > usb info
1: Mass Storage, USB Revision 2.0
- SanDisk Cruzer Blade 4C530201451230114251
- Class: (from Interface) Mass Storage
- PacketSize: 64 Configurations: 1
- Vendor: 0x0781 Product 0x5567 Version 1.38
Configuration: 1
- Interfaces: 1 Bus Powered 200mA
Interface: 0
- Alternate Setting 0, Endpoints: 2
- Class Mass Storage, Transp. SCSI, Bulk only
- Endpoint 1 In Bulk MaxPacket 512
- Endpoint 2 Out Bulk MaxPacket 512
U-Boot > usb tree
Device Tree:
1 Mass Storage (12 Mb/s, 200mA)
SanDisk Cruzer Blade 4C530201451230114251
U-Boot > usb dev
USB device 0: Vendor: SanDisk Rev: 1.26 Prod: Cruzer Blade
Type: Hard Disk
Capacity: 7633.5 MB = 7.4 GB (15633408 x 512)
U-Boot > usb storage
Device 0: Vendor: SanDisk Rev: 1.26 Prod: Cruzer Blade
Type: Hard Disk
Capacity: 7633.5 MB = 7.4 GB (15633408 x 512)
U-Boot > usb part
print_part of 0
Partition Map for USB device 0 -- Partition Type: DOS
Partition Start Sector Num Sectors Type
1 32 15633376 c
print_part of 1
## Unknown partition table
print_part of 2
## Unknown partition table
print_part of 3
## Unknown partition table
print_part of 4
## Unknown partition table
U-Boot >
RE: uBoot and USB using L138F SoM - Added by Jonathan Cormier over 10 years ago
Whats the part number of your dev kit? Should be a 80- number.
RE: uBoot and USB using L138F SoM - Added by Simon Edwards over 10 years ago
The number is 80-000286RI-2
REV B
S/N 132556
Which bootloader are you using? I've been using my own compilation but that is wholly based on the one taken from the Git repository from your wiki link with no modifications.
RE: uBoot and USB using L138F SoM - Added by Simon Edwards over 10 years ago
OK, now I get it. There's no resistor on my board pulling the ID pin down to 0V. I've just put a link between pins 4 & 5 on J100 and its all OK now.
I'll try putting an image on there for it to boot from and let you know.
RE: uBoot and USB using L138F SoM - Added by Simon Edwards over 10 years ago
Yep, loading an image seems to be OK. Next week I'll try the whole image + rootfs and make sure that works too.
Thanks! (sometimes you just need a nudge in the right direction!)
RE: uBoot and USB using L138F SoM - Added by Jonathan Cormier over 10 years ago
As per the On-The-Go spec, the mini USB adapter is supposed to tie the USB_ID pin to GND to indicate it should be put into host mode.
RE: uBoot and USB using L138F SoM - Added by Simon Edwards over 10 years ago
OK, the cable that I used was a miniAB to USB A plug which was then attached to a USB A to USB A gender changer (a little crude, but it works).
Dare I ask why did you add a pull down resistor on your revision C board if the specification states the ID pin is pulled low?!
RE: uBoot and USB using L138F SoM - Added by Jonathan Cormier over 10 years ago
I have been looking into this. It seems that it was a mistake as the added resistor isn't mentioned in our Engineering change request. I noticed the added resistor recently when I was working towards getting the OTG feature working. Currently in the 3.2 kernel you have to force the usb port into HOST or Gadget mode during compile time which is not ideal.
