Ethernet Gadget in U-Boot

[srebers]

Hello Forum,

I’m having some trouble getting the USB RNDIS getting to work in U-Boot with (custom) boards that have the OSD335x-SM device. I created a SD card with MLO and U-Boot image and I configured a static ip. On the host I created network interface with the corresponding host address.

This works fine for a stock Beagle Bone Black but not for our proto board (stripped SM-RED). I suspected the difference in EEPROM could be an issue, so I cloned the contents from the BBB in the proto board but no effect. I tried two versions of U-Boot but both fail on a time out. I also tried on a Pocket Beagle and the OSD3358-SM-RED with same bootloaders, they also fail.

The RNDIS works without problems when the kernel runs with both Linux and Windows hosts. I cannot figure out what the difference in hardware/software can explain this behavior. Any help is much appreciated.

U-Boot 2018.09-00002-g0b54a51eee (Sep 10 2018 - 19:41:39 -0500), Build: jenkins-github_Bootloader-Builder-65

CPU  : AM335X-GP rev 2.1
I2C:   ready
DRAM:  512 MiB
No match for driver 'omap_hsmmc'
No match for driver 'omap_hsmmc'
Some drivers were not found
Reset Source: Power-on reset has occurred.
RTC 32KCLK Source: External.
MMC:   OMAP SD/MMC: 0, OMAP SD/MMC: 1
Loading Environment from EXT4...
** Unable to use mmc 0:1 for loading the env **
Board: BeagleBone Black
 not set. Validating first E-fuse MAC BeagleBone Black:
Timed out in wait_for_event: status=0000 Check if pads/pull-ups of bus are properly configured
BeagleBone: cape eeprom: i2c_probe: 0x54:
Timed out in wait_for_event: status=0000 Check if pads/pull-ups of bus are properly configured
BeagleBone: cape eeprom: i2c_probe: 0x55:
Timed out in wait_for_event: status=0000 Check if pads/pull-ups of bus are properly configured
BeagleBone: cape eeprom: i2c_probe: 0x56:
Timed out in wait_for_event: status=0000 Check if pads/pull-ups of bus are properly configured
BeagleBone: cape eeprom: i2c_probe: 0x57:
Net:   eth0: MII MODE
cpsw, usb_ether
Press SPACE to abort autoboot in 2 seconds 
=> env default -f -a 
## Resetting to default environment 
=> setenv ipaddr 192.168.0.100 
=> setenv serverip 192.168.0.1 
=> setenv ethact usb_ether 
=> setenv usbnet_devaddr f8:dc:7a:00:00:02 
=> setenv usbnet_hostaddr f8:dc:7a:00:00:01 
=> tftp 0x81000000 test.txt 
using musb-hdrc, OUT ep1out IN ep1in STATUS ep2in MAC f8:dc:7a:00:00:02 HOST MAC f8:dc:7a:00:00:01 RNDIS ready 
The remote end did not respond in time.cpsw Waiting for PHY auto negotiation to complete......... TIMEOUT !

U-Boot 2019.10-rc3-00183-g448f11f750 (Sep 05 2019 - 11:47:58 +0200)

CPU  : AM335X-GP rev 2.1
Model: TI AM335x BeagleBone Black
DRAM:  512 MiB
WDT:   Started with servicing (60s timeout)
NAND:  0 MiB
MMC:   OMAP SD/MMC: 0, OMAP SD/MMC: 1
Loading Environment from FAT...  not set. Validating first E-fuse MAC
Net:   eth0: ethernet@4a100000
Warning: usb_ether MAC addresses don't match:
Address in ROM is          de:ad:be:ef:00:01
Address in environment is  38:d2:69:52:3e:b3 , eth1: usb_ether Hit any key to stop autoboot:  0 
=> env default -f -a 
## Resetting to default environment 
=> setenv ipaddr 192.168.0.100 
=> setenv serverip 192.168.0.1 
=> setenv ethact usb_ether 
=> setenv usbnet_devaddr f8:dc:7a:00:00:02 
=> setenv usbnet_hostaddr f8:dc:7a:00:00:01 
=> tftp 0x81000000 test.txt 
using musb-hdrc, OUT ep1out IN ep1in STATUS ep2in MAC f8:dc:7a:00:00:02 HOST MAC f8:dc:7a:00:00:01 RNDIS ready
ethernet@4a100000 Waiting for PHY auto negotiation to complete......... TIMEOUT !

 

[Neeraj Dantu]

srebers,

From the logs(last lines), it looks like the board is trying to use CPSW(ethernet PHY) as the communication interface. The RED board uses a different PHY than the Beaglebone Black. Can you verify that the USB RNDIS is being used by using “printenv ethact”?

Addition info in this thread: https://stackoverflow.com/questions/32747239/can-u-boot-support-more-than-one-ethernet-port

Also note that we demonstrated TFTP boot over USB interface on the RED board in this app note: https://octavosystems.com/app_notes/programming-emmc-with-usb/

Please follow up here.

Best,

Neeraj

[srebers]

Hi Neeraj,

I finally figured this one out. It turned out that that the hardware designer decided to put a 10k pull down on the usb0_id line. Strangely enough this did not have an effect, at least not noticeable, during Linux operation, only in U-Boot.
I also thought that U-Boot was trying the CPSW in MII mode and was giving a timeout because our board uses RGMII. It doesn’t matter how the board is identified, Beagle Bone Black or Pocketbeagle, with the resistor removed and “setenv ethact usb_ether” it will use the USB RNDIS and work correctly.
My statement that it didn’t work on a Pocketbeagle/OSD3358-SM-RED board was incorrect. I think during all the testing some confusion occurred.

Thanks a lot for your input.

Regards,
Stephan

[Neeraj Dantu]

Thanks for the update!

Neeraj

[Author]

Posts