diff options
| author | Alexander Motin <mav@FreeBSD.org> | 2022-10-04 14:34:15 +0000 |
|---|---|---|
| committer | Alexander Motin <mav@FreeBSD.org> | 2022-10-18 01:02:36 +0000 |
| commit | 03acc85e3f2aa5478ae6aa74dd5be7ed05d87a98 (patch) | |
| tree | c4cf733c615b650dba1125f400839c068a26fb95 /sys | |
| parent | 9f4b854c028b5b0395848683388fa78bd569405a (diff) | |
pci: Disable Electromechanical Interlock.
Add sysctl/tunable to control Electromechanical Interlock support.
Disable it by default since Linux does not do it either and it seems
the number of systems having it broken is higher than having working.
This fixes NVMe backplane operation on ASUS RS500A-E11-RS12U server
with AMD EPYC 7402 CPU, where attempts to control reported interlock
for some reason end up in PCIe link loss, while interlock status does
not change (it is not really there).
MFC after: 2 weeks
(cherry picked from commit a58536b91ae3931d222c3e4f1a949ff4a4927fb2)
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/dev/pci/pci_pci.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/sys/dev/pci/pci_pci.c b/sys/dev/pci/pci_pci.c index 0945606bbc50..b735da657a6c 100644 --- a/sys/dev/pci/pci_pci.c +++ b/sys/dev/pci/pci_pci.c @@ -1096,6 +1096,11 @@ pcib_hotplug_present(struct pcib_softc *sc) return (-1); } +static int pci_enable_pcie_ei = 0; +SYSCTL_INT(_hw_pci, OID_AUTO, enable_pcie_ei, CTLFLAG_RWTUN, + &pci_enable_pcie_ei, 0, + "Enable support for PCI-express Electromechanical Interlock."); + static void pcib_pcie_hotplug_update(struct pcib_softc *sc, uint16_t val, uint16_t mask, bool schedule_task) @@ -1135,7 +1140,8 @@ pcib_pcie_hotplug_update(struct pcib_softc *sc, uint16_t val, uint16_t mask, * process of detaching), disable the Electromechanical * Interlock. */ - if (sc->pcie_slot_cap & PCIEM_SLOT_CAP_EIP) { + if ((sc->pcie_slot_cap & PCIEM_SLOT_CAP_EIP) && + pci_enable_pcie_ei) { mask |= PCIEM_SLOT_CTL_EIC; ei_engaged = (sc->pcie_slot_sta & PCIEM_SLOT_STA_EIS) != 0; if (card_inserted != ei_engaged) |