PCI hotplug for downstream endpoints on arm fails because Linux'
PCIe hotplug driver doesn't like the QEMU provided LNKSTA:
pcieport 0000:08:01.0: pciehp: Slot(2): Card present
pcieport 0000:08:01.0: pciehp: Slot(2): Link Up
pcieport 0000:08:01.0: pciehp: Slot(2): Cannot train link: status 0x2000
There's 2 cases where LNKSTA isn't setup properly:
* the downstream device has no express capability
* max link width of the bridge is 0
Move the sanity checks added via 88c869198aa63
("pci: Sanity test minimum downstream LNKSTA") outside of the
branch to make sure downstream ports always have a valid LNKSTA.
Signed-off-by: Sebastian Ott <sebott@redhat.com>
Tested-by: Zhenyu Zhang <zhenyzha@redhat.com>
Message-Id: <20241203121928.14861-1-sebott@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 694632fd44987cc4618612a38ad151047524a590)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index 68a62da0b5..9ffc625cc2 100644
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -999,18 +999,22 @@ void pcie_sync_bridge_lnk(PCIDevice *bridge_dev)
if ((lnksta & PCI_EXP_LNKSTA_NLW) > (lnkcap & PCI_EXP_LNKCAP_MLW)) {
lnksta &= ~PCI_EXP_LNKSTA_NLW;
lnksta |= lnkcap & PCI_EXP_LNKCAP_MLW;
- } else if (!(lnksta & PCI_EXP_LNKSTA_NLW)) {
- lnksta |= QEMU_PCI_EXP_LNKSTA_NLW(QEMU_PCI_EXP_LNK_X1);
}
if ((lnksta & PCI_EXP_LNKSTA_CLS) > (lnkcap & PCI_EXP_LNKCAP_SLS)) {
lnksta &= ~PCI_EXP_LNKSTA_CLS;
lnksta |= lnkcap & PCI_EXP_LNKCAP_SLS;
- } else if (!(lnksta & PCI_EXP_LNKSTA_CLS)) {
- lnksta |= QEMU_PCI_EXP_LNKSTA_CLS(QEMU_PCI_EXP_LNK_2_5GT);
}
}
+ if (!(lnksta & PCI_EXP_LNKSTA_NLW)) {
+ lnksta |= QEMU_PCI_EXP_LNKSTA_NLW(QEMU_PCI_EXP_LNK_X1);
+ }
+
+ if (!(lnksta & PCI_EXP_LNKSTA_CLS)) {
+ lnksta |= QEMU_PCI_EXP_LNKSTA_CLS(QEMU_PCI_EXP_LNK_2_5GT);
+ }
+
pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKSTA,
PCI_EXP_LNKSTA_CLS | PCI_EXP_LNKSTA_NLW);
pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA, lnksta &
--
2.39.5