[U-Boot-Users] USB SUPPORT

[Ken.Fuchs at bench.com]

Aneesh wrote:

>     I am using an at91rm9200dk custom board.
> I want to boot kernel and ram disk from the
> usb stick.for that i tried to enable the usb
> support in the uboot. but now i am getting a
> message like no storage devices found .

Someone else has already suggested using a current
U-Boot version via git rather than v1.1.5, so I
will restrict my comments to the old 1.1.5 version.

> i gave the configurations in
> include/configs/at91rm9200dk.h
> like follows

> #define CONFIG_DOS_PARTITION 1
> #define CONFIG_USB_OHCI      1
> #define CONFIG_USB_STORAGE  1

I have a AT91SAM9261-EK (v1.1.5) with
working USB Storage that also includes  ...

#define LITTLEENDIAN        1

as part of the USB configuration.

> #define CONFIG_COMMANDS \
>       ((CONFIG_CMD_DFL | CFG_CMD_MII | CFG_CMD_NET | CFG_CMD_USB | \
> CFG_CMD_DHCP ) & \
>      ~(CFG_CMD_BDI | \
> CFG_CMD_IMI | \
> CFG_CMD_AUTOSCRIPT | \
> CFG_CMD_FPGA | \
> CFG_CMD_MISC | \
> CFG_CMD_LOADS))

> Is this configuration is right?
> i am not able to acess the USB stick
> using Storage USB Commands. My U-boot
> version is 1.1.5. 
> Any one can help?

--- When you get USB Storage working - either v1.1.5 or git ---

You will probably need (at least want)

#define CFG_CMD_FAT

or

#define CFG_CMD_EXT2

to access the FAT or ext2 directories and
files on the USB Storage device.

This may be useful if your kernel and
ramdisk are files on a FAT/ext2 filesystem
(rather than at a fixed locations on the
raw USB device).

u-boot> setenv bootcmd ...
u-boot> saveenv

--- VFAT ---

You may want to include the following for
long filename support (for FAT filesystems):

#define CONFIG_SUPPORT_VFAT

--- FAT16 vs. FAT32 - Atmel U-Boot v1.1.5 issue? ---

I have found that the USB support is better
when the USB Storage device is FAT16 formatted
rather than FAT32 formatted.  For some reason
not all files were accessible on FAT32
formatted media, but I never had any problem
with FAT16 formatted media.

Sincerely,

Ken Fuchs