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Altera_Forum
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13 years ago

addressing on-chip memory(cyclone IV) from PC via PCIe

Hi freinds, I want to address a on-chip memory in the Cyclone IV FPGA via the HIP PCIe from my computer, so booth the HIP and the Memory are interconnected by the Avalon-MM interface. my ques...
Altera_Forum's avatar
Altera_Forum
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13 years ago

You may also be able to initiate a dma transfer from the host (PCIe master) side. The DMA controller really needs to be coupled closely enough to the PCIe master interface to allow it to do long PCIe transfers (eg 128 bytes).

I don't know which hardware component can do that on a typical x86 pc, nor the os (driver) api calls necessary to setup such transfers. I've only done it on one of the small ppc processor under linux - and I had write my own driver for the dma device.

With extreme care you might manage to use cache-line read/write (probably 64 bytes) to improve transfer performance.