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Altera_Forum
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17 years ago

Altera PCI Express Development Kit: Linux DMA Driver

Hi, I am a newbie to FPGA design and implementation. While installing the PCI express board on LINUX machine, I don't see Demo application driver for DMA read and write for LINUX (Manual talk...
Altera_Forum's avatar
Altera_Forum
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16 years ago

Hi all,

I'm using the PCIe high performance reference design (on the Arria II GX board) on a host that uses legacy mode interrupts. I see the Arria II GX generate an "assert INTA" message followed immediately by a "deassert INTA" message once the descriptor table entry gets processed (I have interrupts only enabled on the last entry in the table). The host sees the interrupt and the ISR is called. However, I don't know what to do to acknowledge the legacy mode interrupt to the reference design, and the FPGA keeps doing the assert/deassert cycle every 39.5uS until the DMA controller is reset.

I didn't see any documentation on acknowledging interrupts. Anyone know what the chaining DMA design wants (in legacy interrupt mode)?

Thanks,

Tony