Sigmastar USB2.0 Host Debug SOP Manual

REVISION HISTORY

Revision No.
Description
 Date
1.0
  • Initial release
    		•  12/03/2024

    Issue 1. Device not recognized

    Figure 1 Troubleshooting for device not recognized

    Process Method
    A The log level may be too low to print the USB enumeration logs, echo 7 > /proc/sys/kernel/printk to raise the log level
    B Required kernel modules for usb2.0 host: ehci-hcd.ko sstar-usb2-phy.ko Note: Some modules may be built-in
    C Some chips have many different boards with varying numbers of USB ports, controlled by status in the board-level DTS, so it is necessary to confirm if the DTS status is okay
    D Confirm if there is power on the vbus, check if the vbus jumper for the port is connected, can measure with a multimeter, or possibly use a powered Wi-Fi device to see if the light is on

    Issue 2. Upgrade via usbstar fails in uboot

    Figure 2 Troubleshooting for usbstar upgrade failure

    Process Method
    A Confirm if usbstar and usb2.0 under menuconfig are selected
    B Check if the status related to usb2.0 in the DTS is okay
    C Check if there is power on the vbus, measure with a multimeter
    D If not, specify the upgrade image name with usbstar -f, the default upgrade filename is SigmastarUpgrade.bin
    E Check if the USB drive has multiple partitions, files placed in non-first partitions, usbstar defaults to read the first partition of the USB drive
    F Current USB drive upgrades only support FAT32 format

    Issue 3. USB drive mount fails

    Figure 3 Troubleshooting for USB drive mount failure

    Process Method
    A First confirm if the USB drive is recognized, if not, check the process for not being recognized
    B Use cat /proc/filesystem to see if the corresponding file system for the USB drive is loaded under kernel
    C For example, mount /dev/sda1 /mnt -t vfat, it could also be sdb1, sdc1....

    Issue 4. Unable to recognize high speed when connecting USB2.0 device

    Figure 4 Troubleshooting for inability to recognize high speed

    Process Method
    A If high speed is recognized, there will be a log stating new high-speed USB device number 16 using ehci-hcd
    B Use this device on a PC, use usbtree to check if the Device maximum Speed descriptor is high-speed
    C It may be an issue with the quality of the cable, try testing with another cable
    D If not plugged in tightly, it may cause poor contact and lead to abnormal recognition