Messages in this thread | | | From | Logan Gunthorpe <> | Date | Mon, 23 Oct 2017 16:04:26 -0600 | Subject | Re: Enabling peer to peer device transactions for PCIe devices |
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On 23/10/17 10:08 AM, David Laight wrote: > It is also worth checking that the hardware actually supports p2p transfers. > Writes are more likely to be supported then reads. > ISTR that some intel cpus support some p2p writes, but there could easily > be errata against them.
Ludwig mentioned a PCIe switch. The few switches I'm aware of support P2P transfers. So if everything is setup correctly, the TLPs shouldn't even touch the CPU.
But, yes, generally it's a good idea to start with writes and see if they work first.
Logan
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