From d7346e614f4ec353f9b24bb69bfeaf1ade287e07 Mon Sep 17 00:00:00 2001 From: Igor Mammedov Date: Fri, 23 Jul 2021 05:04:24 -0400 Subject: [PATCH] acpi: x86: pcihp: add support hotplug on multifunction bridges Commit [1] switched PCI hotplug from native to ACPI one by default. That however breaks hotplug on following CLI that used to work: -nodefaults -machine q35 \ -device pcie-root-port,id=pcie-root-port-0,multifunction=on,bus=pcie.0,addr=0x1,chassis=1 \ -device pcie-root-port,id=pcie-root-port-1,port=0x1,addr=0x1.0x1,bus=pcie.0,chassis=2 where PCI device is hotplugged to pcie-root-port-1 with error on guest side: ACPI BIOS Error (bug): Could not resolve symbol [^S0B.PCNT], AE_NOT_FOUND (20201113/psargs-330) ACPI Error: Aborting method \_SB.PCI0.PCNT due to previous error (AE_NOT_FOUND) (20201113/psparse-531) ACPI Error: Aborting method \_GPE._E01 due to previous error (AE_NOT_FOUND) (20201113/psparse-531) ACPI Error: AE_NOT_FOUND, while evaluating GPE method [_E01] (20201113/evgpe-515) cause is that QEMU's ACPI hotplug never supported functions other then 0 and due to bug it was generating notification entries for not described functions. Technically there is no reason not to describe cold-plugged bridges (root ports) on functions other then 0, as they similarly to bridge on function 0 are unpluggable. So since we need to describe multifunction devices iterate over fuctions as well. But describe only cold-plugged bridges[root ports] on functions other than 0 as well. 1) Fixes: 17858a169508609ca9063c544833e5a1adeb7b52 (hw/acpi/ich9: Set ACPI PCI hot-plug as default on Q35) Signed-off-by: Igor Mammedov Reported-by: Laurent Vivier Message-Id: <20210723090424.2092226-1-imammedo@redhat.com> Fixes: 17858a169508609ca9063c544833e5a1adeb7b52 (hw/acpi/ich9: Set ACPI PCI hot-plug as default on Q35)
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reported-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/i386/acpi-build.c | 44 ++++++++++++++++++++++++++++++-------------- 1 file changed, 30 insertions(+), 14 deletions(-) diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index 17836149fe..a33ac8b91e 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -374,7 +374,7 @@ static void build_append_pci_bus_devices(Aml *parent_scope, PCIBus *bus, Aml *dev, *notify_method = NULL, *method; QObject *bsel; PCIBus *sec; - int i; + int devfn; bsel = object_property_get_qobject(OBJECT(bus), ACPI_PCIHP_PROP_BSEL, NULL); if (bsel) { @@ -384,23 +384,31 @@ static void build_append_pci_bus_devices(Aml *parent_scope, PCIBus *bus, notify_method = aml_method("DVNT", 2, AML_NOTSERIALIZED); } - for (i = 0; i < ARRAY_SIZE(bus->devices); i += PCI_FUNC_MAX) { + for (devfn = 0; devfn < ARRAY_SIZE(bus->devices); devfn++) { DeviceClass *dc; PCIDeviceClass *pc; - PCIDevice *pdev = bus->devices[i]; - int slot = PCI_SLOT(i); + PCIDevice *pdev = bus->devices[devfn]; + int slot = PCI_SLOT(devfn); + int func = PCI_FUNC(devfn); + /* ACPI spec: 1.0b: Table 6-2 _ADR Object Bus Types, PCI type */ + int adr = slot << 16 | func; bool hotplug_enabled_dev; bool bridge_in_acpi; bool cold_plugged_bridge; if (!pdev) { - if (bsel) { /* add hotplug slots for non present devices */ + /* + * add hotplug slots for non present devices. + * hotplug is supported only for non-multifunction device + * so generate device description only for function 0 + */ + if (bsel && !func) { if (pci_bus_is_express(bus) && slot > 0) { break; } - dev = aml_device("S%.02X", PCI_DEVFN(slot, 0)); + dev = aml_device("S%.02X", devfn); aml_append(dev, aml_name_decl("_SUN", aml_int(slot))); - aml_append(dev, aml_name_decl("_ADR", aml_int(slot << 16))); + aml_append(dev, aml_name_decl("_ADR", aml_int(adr))); method = aml_method("_EJ0", 1, AML_NOTSERIALIZED); aml_append(method, aml_call2("PCEJ", aml_name("BSEL"), aml_name("_SUN")) @@ -436,9 +444,18 @@ static void build_append_pci_bus_devices(Aml *parent_scope, PCIBus *bus, continue; } - /* start to compose PCI slot descriptor */ - dev = aml_device("S%.02X", PCI_DEVFN(slot, 0)); - aml_append(dev, aml_name_decl("_ADR", aml_int(slot << 16))); + /* + * allow describing coldplugged bridges in ACPI even if they are not + * on function 0, as they are not unpluggable, for all other devices + * generate description only for function 0 per slot + */ + if (func && !bridge_in_acpi) { + continue; + } + + /* start to compose PCI device descriptor */ + dev = aml_device("S%.02X", devfn); + aml_append(dev, aml_name_decl("_ADR", aml_int(adr))); if (bsel) { /* @@ -496,7 +513,7 @@ static void build_append_pci_bus_devices(Aml *parent_scope, PCIBus *bus, build_append_pci_bus_devices(dev, sec_bus, pcihp_bridge_en); } - /* slot descriptor has been composed, add it into parent context */ + /* device descriptor has been composed, add it into parent context */ aml_append(parent_scope, dev); } @@ -525,13 +542,12 @@ static void build_append_pci_bus_devices(Aml *parent_scope, PCIBus *bus, /* Notify about child bus events in any case */ if (pcihp_bridge_en) { QLIST_FOREACH(sec, &bus->child, sibling) { - int32_t devfn = sec->parent_dev->devfn; - if (pci_bus_is_root(sec)) { continue; } - aml_append(method, aml_name("^S%.02X.PCNT", devfn)); + aml_append(method, aml_name("^S%.02X.PCNT", + sec->parent_dev->devfn)); } }