TDA4VM: MAC2MAC SPEED problem for QNX

HONGRUN ZHAO

Part Number: TDA4VM

Hi experts:

I test mac2mac speed under QNX system . the speed is not 1G only 500M but on linux the speed is up to 930M

then i check the patch

[FAQ] DRA829VXEVM: Is it possible to connect two DRA829 EVMs via SGMII - Processors forum - Processors - TI E2E support forums

i think QNX system need modify some parameter reference kernel_cpsw9g_virt_increase_rxtx_desc - 256- > 500

Could you please introduce how to modfiy the parameter at qnx system ?

Best Regards!

over 4 years ago

0 KB over 4 years ago

TI__Guru** 121841 points

Hi,

Apologies for the slow response, TI team is looking into the query.

Regards,

+1 Praveen Rao over 4 years ago in reply to KB

TI__Mastermind 48263 points

Hello,

Thanks for your query.

Yes, the QNX DEVNP CPSW9G virtual driver has a speed of ~550Mbps when test with the default "iperf -c <ipaddr>" option. But it can increase up to 900Mbps with "iperf -c <ipaddress> -w 128K". Suggest giving this a try.

Regarding increasing the DMA descriptors from 256 to 500 is described below:

Note that the driver today by default supports 128 descriptors for RX and 128 descriptors for TX. But this can increase to a MAX of 256 for both RX and TX respectively. This can be specified using the command line parameters when starting the driver.

For example:

io-pkt-v6-hc -d cpsw9g tx_descriptor_cnt=256,rx_descriptor_cnt=256

The different command line parameter options support by the driver can be using the command:

use devnp_cpsw9g.so

Hope this helps.

Thanks.

0 HONGRUN ZHAO over 4 years ago in reply to Praveen Rao

Intellectual 555 points

thanks for your repaly

I read a lot of documents provided by QNX and Ti, and did not find the description of this parameter. Which document describes this parameter

0 Praveen Rao over 4 years ago in reply to HONGRUN ZHAO

TI__Mastermind 48263 points

Hi,

All the driver option supported can be looked at using the "use" command on the driver library. This is mentioned in the document link:

4. PSDK QNX Components — Processor SDK QNX J721E (ti.com)

Thanks.