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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...
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Altera_Forum
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16 years ago

Arria is on PCIe bus.PCIe has his own interrupt controller,so there are no physical interrupts.They are virtual.In my case I received a IRQ#4538 line using Linux.

To start DMA read/write you have to write the number of descriptors to transfer, to the &read_header->w3 in the altpciechdma driver.

Example:iowrite32(n,&read_header->w3).

Look through the driver source code.

Everything is commented.

ug_pci_express.pdf has the description of the Altera MegaCore function.

Read /Documents/DMA.txt in your Linux documentation to better understand the chaining DMA.