STM32F407 + USB + ULPI Interface

[Giovanni]

Hi,

I found that the HW FIFO multiplier greatly affects performance, in structure USBEndpointConfig it is usually 2, you should try 4 or even 8. For CDC applications it is not a problem because there is plenty FIFO RAM available.

Giovanni

[chradev]

I try it increasing USBEndpointConfig.in_multiplier for USB FS/HS data endpoints only from 2 (default) to 4 and 8.
In both cases (4 and 8) USB HS throughput increases from ~5 to ~7.4 MBps when connected to Linux on a20-Lime2-SOM.
When USB HS was connected to i7 PC with Windows 7 throughput increases from ~2 to ~2.5 MBps (or ~25%).

Unfortunately, connection for both USB FS and HS become unstable and even Linux on a20-Lime2-SOM hangs (no such behavior till now).
Regarding STM32F405/7 Data Sheet: Combined Rx and Tx FIFO size is 320 × 35 bits / 1 Kbit × 35 for OTG-FS/HS respectively.
Can this strange behavior be explained by having 2 CDC devices (on USB FS and HS) and 512 bytes USB HS packet size in my case?

Chris

[Giovanni]

You can't have a queue of x4 or x8 if your packet size is 512, there is not enough RAM. You should get an assertion because that. Could you try with smaller packets and longer FIFOs? 64x4 is working for me.

I fixed a regression that could cause instability, it caused SV#8 errors because a change in ST header files, make sure to updated to the latest revision.

Giovanni

[Giovanni]

Using the linear API (the new synchronous variant of it) I am seeing 16MB/s+ by transmitting blocks of 1KB, the rate really improves using even larger blocks.

See the demo \testhal\STM32\STM32F7xx\USB_RAW

It is still work in progress, it is still buggy and not optimized.

Giovanni

[Giovanni]

It is stable now, there was a problem on USB reconnection.

Giovanni

[DeusExMachina]

I try it increasing USBEndpointConfig.in_multiplier for USB FS/HS data endpoints only from 2 (default) to 4 and 8.
In both cases (4 and 8) USB HS throughput increases from ~5 to ~7.4 MBps when connected to Linux on a20-Lime2-SOM.
When USB HS was connected to i7 PC with Windows 7 throughput increases from ~2 to ~2.5 MBps (or ~25%).

Unfortunately, connection for both USB FS and HS become unstable and even Linux on a20-Lime2-SOM hangs (no such behavior till now).
Regarding STM32F405/7 Data Sheet: Combined Rx and Tx FIFO size is 320 × 35 bits / 1 Kbit × 35 for OTG-FS/HS respectively.
Can this strange behavior be explained by having 2 CDC devices (on USB FS and HS) and 512 bytes USB HS packet size in my case?

Chris

chradev, could you please share your project for 405? I failed with porting F7 demo to F407. Maybe it's a board issue, and I need to check it.

[chradev]

I have already do that in my previous post. You can download it following the link:
http://forum.chibios.org/phpbb/download/file.php?id=933

Regards
Chris

[DeusExMachina]

Thanks.

[DeusExMachina]

I use ulpi and Chibios 16.1.1 stable
I was able to run several USB examples on my board, including testhal demo. But I have a problem - periodically (but really often) I have a trouble

Code: Select all

  osalDbgAssert(!usbGetTransmitStatusI(usbp, ep), "already transmitting");

this is called from endpoint setup usb.c 765 (_usb_ep0setup)
previously in _usb_isr_invoke_setup_cb() usb.c 410 (otg_epout_handler)
otg_epout_handler() usb_ldd.c 609 (usb_lld_serve_interrupt)

My hardware setup is similar, the only difference that I run MCU on 48 MHz. What could go wrong?

[DeusExMachina]

Maybe someone can share a basic example of HID device using HS ULPI? (Sounds ridiculous, but I really need it)