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Altera_Forum
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10 years ago

Altera JTAG UART used by kernel does not match IRQ assignment made in Qsys

Hi all, I'm currently developing a 3.10.31-ltsi kernel that running on a Nios II-based system. This system also contains several components including an Altera JTAG UART, USB host controller a...
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Altera_Forum
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10 years ago

Hi Bhaumik,

So if I understand you correctly, if you didn't make any changes to the .dts file then the entry for this component in the device tree blob was still set to 1, correct? If that's the case then what IRQ did the kernel end up using? There seems to be a direct conflict between the IRQ setting in Qsys (IRQ 4) and the .dts/.dtb file (IRQ 1). I have always had problems if the IRQ settings in the Qsys system and the .dts/.dtb files didn't match.

I assume you are using Linux as your OS (or are you using a HAL-based system?). If you are using Linux would it be possible for you to run the "cat /proc/interrupts" command to see how the interrupts mapped to the kernel.

Also, could you tell me what IRQ you have assigned to your USB Host Controller? Can you say which manufacturer of the USB Host Controller core you are using?

I'm just trying to run down all the possible differences between our systems.

Thanks again for all your help. Let me know if you have any questions and I look forward to your response.

- Brad