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| author | Christian König <ckoenig.leichtzumerken@gmail.com> | 2019-04-18 13:58:59 +0200 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2019-05-01 16:53:39 -0500 |
| commit | 0f97da83102610db886e8b688b9029e080e6d511 (patch) | |
| tree | f76f4b8095249e8266ca231ff82c5aceaa530477 /tools/perf/scripts/python/export-to-postgresql.py | |
| parent | 9e98c678c2d6ae3a17cb2de55d17f69dddaa231b (diff) | |
PCI/P2PDMA: Allow P2P DMA between any devices under AMD ZEN Root Complex
The PCI specs say that peer-to-peer DMA should be supported between any two
devices that have a common upstream PCI-to-PCI bridge. But devices under
different Root Ports don't share a common upstream bridge, and PCIe r4.0,
sec 1.3.1, says routing peer-to-peer transactions between Root Ports in the
same Root Complex is optional.
Many Root Complexes, including AMD ZEN, *do* support peer-to-peer DMA even
between Root Ports. Add a whitelist and allow peer-to-peer DMA if both
participants are attached to a Root Complex known to support it.
Link: https://lore.kernel.org/linux-pci/20190418115859.2394-1-christian.koenig@amd.com
Signed-off-by: Christian König <christian.koenig@amd.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Diffstat (limited to 'tools/perf/scripts/python/export-to-postgresql.py')
0 files changed, 0 insertions, 0 deletions