Linux/AM5728: USB DMA buffer size

Hi Aither,

The xHCI controller on AM5728 doesn't require any specific size of DMA buffers, it can handle any DMA-capable buffer. The issue you have sounds like something else.

Hi, Bin
First, thanks you for your quick response.

This USB 3.0 camera works well at Windows 10 and Ubuntu16.04, but do not works well at AM5728.
This USB3.0 camera works well normally at AM5728 EVM, and my app gets the last image from the camera. But sometimes my app has a heavy workload, then UART terminal displays "xhci-hcd xhci-hcd.1.auto: WARN Event TRB for slot 4 ep 2 with no TDs queued?" and my app could not get the image from the camera.
1. How can I solve this problem?
2. Why the above message from TX event handler(I have found this message linux-4.9.69/src/drivers/usb/host/xhci-ring.c handle_tx_event() function) is outputted?
Please lead me to solve.

Thanks you again.
Best Regards.
aither

Aither,

What Processor SDK version do you use?

Please provide the descriptors of the camera. You can get it by plug it to Ubuntu PC and run the following command on the PC.
$ lsusb -v -d <vid:pid>

When you say your app has a heavy load, do you mean your app itself or your Linux system on AM5728?
What is the app? A program you developed or you get from Linux community?

Hi, Bin,
Thanks for your kind response.
Now I use ti-processor-sdk-linux-am57xx-evm-04.03.00.05 and AM5728 EVM. The camera descriptor is below:
root@ubuntu:/home/aither# lsusb -v -d 2676:

Bus 001 Device 002: ID 2676:ba03 Basler AG
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.10
bDeviceClass 239 Miscellaneous Device
bDeviceSubClass 2 ?
bDeviceProtocol 1 Interface Association
bMaxPacketSize0 64
idVendor 0x2676 Basler AG
idProduct 0xba03
bcdDevice 0.00
iManufacturer 1 Basler
iProduct 2 daA1920-15um
iSerial 3 22410409
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 76
bNumInterfaces 2
bConfigurationValue 1
iConfiguration 0
bmAttributes 0x80
(Bus Powered)
MaxPower 400mA
Interface Association:
bLength 8
bDescriptorType 11
bFirstInterface 0
bInterfaceCount 2
bFunctionClass 239 Miscellaneous Device
bFunctionSubClass 5 USB3 Vision
bFunctionProtocol 0
iFunction 5 USB3 Vision Device
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 2
bInterfaceClass 239 Miscellaneous Device
bInterfaceSubClass 5 USB3 Vision
bInterfaceProtocol 0
iInterface 0
** UNRECOGNIZED: 14 24 01 00 00 01 00 00 00 01 00 04 01 02 00 06 07 03 08 0c
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x04 EP 4 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x84 EP 4 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 239 Miscellaneous Device
bInterfaceSubClass 5 USB3 Vision
bInterfaceProtocol 2
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Binary Object Store Descriptor:
bLength 5
bDescriptorType 15
wTotalLength 22
bNumDeviceCaps 2
USB 2.0 Extension Device Capability:
bLength 7
bDescriptorType 16
bDevCapabilityType 2
bmAttributes 0x00000006
Link Power Management (LPM) Supported
SuperSpeed USB Device Capability:
bLength 10
bDescriptorType 16
bDevCapabilityType 3
bmAttributes 0x00
wSpeedsSupported 0x000c
Device can operate at High Speed (480Mbps)
Device can operate at SuperSpeed (5Gbps)
bFunctionalitySupport 3
Lowest fully-functional device speed is SuperSpeed (5Gbps)
bU1DevExitLat 10 micro seconds
bU2DevExitLat 2047 micro seconds
Device Status: 0x0000
(Bus Powered)
root@ubuntu:/home/aither#

My "workload" is my app's load, and my app is image processing app that I have developed.
When image variation is too much, my image processing engine will have heavy load.
Please help me and lead me to solve...

Best Regards.
Thank again.
Aither

Hi, Bin

First, thanks for your response.

1. The camera connects as USB3.0:

[ 215.250137] usb 2-1.3: new SuperSpeed USB device number 3 using xhci-hcd

2. My test program is very simple from Basler SDK Samples, and when I have tested at TI PSDK 5.0, no problem appeared. So I think that perhaps USB3.0 driver module. Can you resolve my issue for TI PSDK 4.3?

Best Regards.

Thanks you again.

Aither.