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Altera_Forum
Honored Contributor
Honored ContributorSimple PCIe DMA
I guess I could try to find the appropriate documentation, but I'll cheat and ask here! I need to find which DMA block to ask our HW team to add to qsys in order to do burst PCIe transfers from...
Altera_ForumHonored Contributor
Honored ContributorHi Nial,
--- Quote Start --- It's simple enough and works well, all you have to do is set up the address translation table the way you want it. --- Quote End --- The original poster wanted to be able to DMA to an arbitrary 64-bit address, and he wanted 10 different DMA engines. As far as I am aware, the TXS port on the Qsys PCI IP core would only allow one value for the 32 MSBs of the address, so the 10 DMA controllers would be restricted to a 4GB region of the PCIe memory map. Its pretty common now for host PCs to have in excess of 4GB, so a driver on the host could easily provide PCIe DMA target page addresses that cross a 32-bit address boundary. Bottom line is that the Qsys PCIe core PCIe bus master interface is too simplistic. Cheers, Dave
