From 219e638f3b3f3e34b5cf00c0a0d536a7e0155f70 Mon Sep 17 00:00:00 2001 From: Igor Mammedov Date: Thu, 12 Jan 2023 15:02:54 +0100 Subject: [PATCH] pcihp: do not put empty PCNT in DSDT count number of PCNT methods that actually call Notify and if there aren't any, drop PCNT altogether. It mostly affects 'Q35' tests where there is no root-ports /bridges attached and 'PC' machine when ACPI PCI hotplug is completely disabled. Expected ASL change: - Method (PCNT, 0, NotSerialized) - { - } ... Method (_E01, 0, NotSerialized) // _Exx: Edge-Triggered GPE { - Acquire (\_SB.PCI0.BLCK, 0xFFFF) - \_SB.PCI0.PCNT () - Release (\_SB.PCI0.BLCK) } Signed-off-by: Igor Mammedov Message-Id: <20230112140312.3096331-23-imammedo@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/i386/acpi-build.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index d434ad9189..6368fcefa3 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -496,12 +496,13 @@ static void build_append_pci_bus_devices(Aml *parent_scope, PCIBus *bus, qobject_unref(bsel); } -static void build_append_notfication_callback(Aml *parent_scope, +static bool build_append_notfication_callback(Aml *parent_scope, const PCIBus *bus) { Aml *method; PCIBus *sec; QObject *bsel; + int nr_notifiers = 0; QLIST_FOREACH(sec, &bus->child, sibling) { Aml *br_scope = aml_scope("S%.02X", sec->parent_dev->devfn); @@ -509,7 +510,8 @@ static void build_append_notfication_callback(Aml *parent_scope, !object_property_find(OBJECT(sec), ACPI_PCIHP_PROP_BSEL)) { continue; } - build_append_notfication_callback(br_scope, sec); + nr_notifiers = nr_notifiers + + build_append_notfication_callback(br_scope, sec); aml_append(parent_scope, br_scope); } @@ -530,6 +532,7 @@ static void build_append_notfication_callback(Aml *parent_scope, aml_int(1))); /* Device Check */ aml_append(method, aml_call2("DVNT", aml_name("PCID"), aml_int(3))); /* Eject Request */ + nr_notifiers++; } /* Notify about child bus events in any case */ @@ -544,6 +547,7 @@ static void build_append_notfication_callback(Aml *parent_scope, aml_append(parent_scope, method); qobject_unref(bsel); + return !!nr_notifiers; } static Aml *aml_pci_pdsm(void) @@ -1742,20 +1746,26 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, aml_append(dsdt, sb_scope); if (pm->pcihp_bridge_en || pm->pcihp_root_en) { + bool has_pcnt; + Object *pci_host = acpi_get_i386_pci_host(); PCIBus *bus = PCI_HOST_BRIDGE(pci_host)->bus; scope = aml_scope("\\_SB.PCI0"); - build_append_notfication_callback(scope, bus); - aml_append(dsdt, scope); + has_pcnt = build_append_notfication_callback(scope, bus); + if (has_pcnt) { + aml_append(dsdt, scope); + } scope = aml_scope("_GPE"); { method = aml_method("_E01", 0, AML_NOTSERIALIZED); - aml_append(method, - aml_acquire(aml_name("\\_SB.PCI0.BLCK"), 0xFFFF)); - aml_append(method, aml_call0("\\_SB.PCI0.PCNT")); - aml_append(method, aml_release(aml_name("\\_SB.PCI0.BLCK"))); + if (has_pcnt) { + aml_append(method, + aml_acquire(aml_name("\\_SB.PCI0.BLCK"), 0xFFFF)); + aml_append(method, aml_call0("\\_SB.PCI0.PCNT")); + aml_append(method, aml_release(aml_name("\\_SB.PCI0.BLCK"))); + } aml_append(scope, method); } aml_append(dsdt, scope);