linuxkpi: handle ARI
ClosedPublic
Actions

Authored by kib on Jan 4 2021, 9:35 PM.

Details

Reviewers

• hselasky
manu
bz

Commits

rGde27805fee0b: linuxkpi: handle ARI

Summary

Stop trying to manually calculate RID, which cannot be done correctly by PCI_DEVFN(). Use PCI_GET_RID() method instead.

Do not use pci_find_dbsf() to go from the linux pci_dev to freebsd device_t. First, device is readily available as dev.bsddev. Second, using pci_find_dbsf() fails for ARI-enabled functions with large function numbers, because PCI_SLOT()/PCI_FUNC() are for non-ARI.

Sponsored by: Mellanox Technologies/NVidia Networking

Diff Detail

Repository

rG FreeBSD src repository

Lint

Lint Not Applicable

Unit

Tests Not Applicable

Event Timeline

kib created this revision.Jan 4 2021, 9:35 PM

Herald added subscribers: linuxkpi, emaste. · View Herald TranscriptJan 4 2021, 9:35 PM

kib requested review of this revision.Jan 4 2021, 9:35 PM

manu added inline comments.Jan 6 2021, 9:20 AM

sys/compat/linuxkpi/common/src/linux_pci.c
271	Why do we use the parent parent here ?

kib added inline comments.Jan 6 2021, 9:56 AM

sys/compat/linuxkpi/common/src/linux_pci.c
271	PCI_GET_ID() requires the first arg to be bus, and ends up as the PCIB_GET_RID() call on the parent of the bus. Hans explained to me that in drm case, dev is some pseudo-device set to be child of the normally enumerated PCI device. If this is correct, then parent-parent there just re-aligns the things to be same for drm and non-drm. I do not think it is enough to set ivars to have GET_RID() working. Can you test drm with this patch, please ?

manu added inline comments.Jan 6 2021, 10:02 AM

sys/compat/linuxkpi/common/src/linux_pci.c
271	That will resolve to the pciN device for drm and not pcibN I think. pcib0 pci0 hostb0 vgapci0 drmn0 I'll test today and report the result.

kib added inline comments.Jan 6 2021, 10:23 AM

sys/compat/linuxkpi/common/src/linux_pci.c
271	I expect that the call needs the pair pci0/vgapci0. Then pci_get_id_method() does PCIB_GET_ID(device_get_parent(pci0) == pcib0, vgapci0). But again, this is all from the code reading. Testing and some iterations to make it work will be much appreciated.