OS - linux-2.6.37-psp04.04.00.01
We have a USB serial modem connected to USB0 interface. We are trying to do PPP using the modem. But facing problem with pinging with packet size greater than MTU size.
Below are the steps followed.
1. Establish a ppp connection using the modem interface.
2. Ping with packets less than or equal to MTU
No issues, modem works fine, responds to AT commands after stopping the pppd
3. Ping with packets greater than MTU.
USB teardown error happens and modem ceases to function.
Logs:
[ 274.540000] cppi41_channel_abort: DMA busy, status = 2
[ 274.540000] Rx channel teardown, cppi_ch = d241267c
[ 274.540000] usb_rx_ch_teardown 1057: teardown Desc not found
[ 274.540000] Returning PD ffc5ffc0 to the free PD list
[ 274.540000] musb-hdrc musb-hdrc.1: Data toggle same as previous (=1) on ep10
[ 274.810000] cppi41_channel_abort: DMA busy, status = 2
[ 274.810000] Rx channel teardown, cppi_ch = d24126c0
[ 274.810000] usb_rx_ch_teardown 1057: teardown Desc not found
[ 274.810000] Returning PD ffc5ff80 to the free PD list
[ 274.810000] musb-hdrc musb-hdrc.1: Data toggle same as previous (=0) on ep11
[ 275.580000] cppi41_channel_abort: DMA busy, status = 2
[ 275.580000] Tx channel teardown, cppi_ch = d2412280
[ 275.580000] Returning PD ffc5fec0 to the free PD list
Has anyone faced a similar issue.