| Message ID | 20231009195747.889326-5-stewart.hildebrand@amd.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Kconfig for PCI passthrough on ARM | expand |
Hi Stewart, On 09/10/2023 20:57, Stewart Hildebrand wrote: > Set the pci flags in xen_arch_domainconfig to enable vPCI for dom0. > > Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com> > --- > Julien had a suggestion to make this conditional on pci_passthrough_enabled [1]. > However, in v5 of the PCI ARM SMMU series [2], we propose removing the > pci_passthrough_enabled flag. If pci_passthrough_enabled is gone, the conditions > under which vPCI should be enabled for dom0 aren't entirely clear to me (other > than CONFIG_HAS_VPCI=y). I think it should be based on whether Xen detected a PCI hostbridge in system. I haven't looked which variable/function could be used in Xen for this purpose. Cheers,
On 10/20/23 13:33, Julien Grall wrote: > Hi Stewart, > > On 09/10/2023 20:57, Stewart Hildebrand wrote: >> Set the pci flags in xen_arch_domainconfig to enable vPCI for dom0. >> >> Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com> >> --- >> Julien had a suggestion to make this conditional on pci_passthrough_enabled [1]. >> However, in v5 of the PCI ARM SMMU series [2], we propose removing the >> pci_passthrough_enabled flag. If pci_passthrough_enabled is gone, the conditions >> under which vPCI should be enabled for dom0 aren't entirely clear to me (other >> than CONFIG_HAS_VPCI=y). > > I think it should be based on whether Xen detected a PCI hostbridge in > system. I haven't looked which variable/function could be used in Xen > for this purpose. We can slightly tweak pci_host_iterate_bridges_and_count() and use that. Also, a full revert of the pci_passthrough_enabled flag over in the SMMU series probably wasn't the best approach, so I'll add pci_passthrough_enabled into the mix too. > > Cheers, > > -- > Julien Grall
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index 24c9019cc43c..c1174535f430 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -3912,6 +3912,9 @@ void __init create_dom0(void) panic("SVE vector length error\n"); } + if ( IS_ENABLED(CONFIG_HAS_VPCI) ) + dom0_cfg.arch.pci_flags = XEN_DOMCTL_CONFIG_PCI_VPCI; + dom0 = domain_create(0, &dom0_cfg, CDF_privileged | CDF_directmap); if ( IS_ERR(dom0) ) panic("Error creating domain 0 (rc = %ld)\n", PTR_ERR(dom0));
Set the pci flags in xen_arch_domainconfig to enable vPCI for dom0. Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com> --- Julien had a suggestion to make this conditional on pci_passthrough_enabled [1]. However, in v5 of the PCI ARM SMMU series [2], we propose removing the pci_passthrough_enabled flag. If pci_passthrough_enabled is gone, the conditions under which vPCI should be enabled for dom0 aren't entirely clear to me (other than CONFIG_HAS_VPCI=y). v2->v3: * new patch [1] https://lists.xenproject.org/archives/html/xen-devel/2023-10/msg00475.html [2] https://lists.xenproject.org/archives/html/xen-devel/2023-10/msg00210.html --- xen/arch/arm/domain_build.c | 3 +++ 1 file changed, 3 insertions(+)