Access DCU registers from User space

[riz1231]

Hello,

We are not able to access DCU memory mapped registers from user mode (non-privileged) on Vybrid.  Is there any specific settings we have to perform to make it happen?

Note: we are trying to access DCU registers starting from 0x40058000 address (Vybrid Reference Manual, Rev. 7, 06/2014 Page 3034)

Thanks,

Rizwan Rasheed

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[rendy]

Hi,

please download Vybrid Security Reference manual. There read mainly chapter #5 and chapter #7. There you will get more information about the CSU unit, which should allow you to set access rights to various NIC masters/slaves. If you have further questions, write them here and mention me (character '@' + my name).

Regards

Rene

[kenmacfarlane]

@ReneKolarik, does MQX support user & supervisor modes? I'm told that There is no user-mode/supervisor-mode split in Vybrid

[alejandrolozan1]

Hi,

Were you able to acces the registers in user-mode.

Would you be nice enough to share your solution?

Best Regards,

Alejandro

[VilemZ]

Hello,

How can you tried access to registers? And do you read section "55.7 Register protection" on VYBRIDRM? It can be helpful.

Best Regards

Vilem

[kenmacfarlane]

55.7 is about "Timing, Error and Interrupt Management" in Vybrid Reference Manual, Rev. 5, 07/2013. Has a section on Register protection been introduced? Perhaps this will explain why code that previously worked on a bare metal DCU demo, does not change the DCU registers (albeit on an MQX-based application).

[VilemZ]

Hi Kenneth,

In Vybrid Reference Manual rev. 7, 06/2014 is 55.7 about Register protection.

Vilem