| Message ID | 20241203121928.14861-1-sebott@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] pci: ensure valid link status bits for downstream ports | expand |
On Tue, 3 Dec 2024 13:19:28 +0100 Sebastian Ott <sebott@redhat.com> wrote: > 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> > --- > hw/pci/pcie.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) Reviewed-by: Alex Williamson <alex.williamson@redhat.com> > diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c > index 0b455c8654..1b12db6fa2 100644 > --- a/hw/pci/pcie.c > +++ b/hw/pci/pcie.c > @@ -1113,18 +1113,22 @@ 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 &
diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c index 0b455c8654..1b12db6fa2 100644 --- a/hw/pci/pcie.c +++ b/hw/pci/pcie.c @@ -1113,18 +1113,22 @@ 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 &
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> --- hw/pci/pcie.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)