From 99d09dd32820f5702031e3c08c81f8c209dc2220 Mon Sep 17 00:00:00 2001 From: Igor Mammedov Date: Mon, 3 Feb 2014 11:44:59 +0100 Subject: pcihp: make pci_read() mmio calback compatible with legacy ACPI hotplug due to recent change introduced by: "pcihp: reduce number of device check events" 'up' field is cleared right after it's read. This is incompatible with legacy BIOS ACPI code where PCNF ACPI method reads this field 32 times. To make pci_read mmio callback compatible with legacy 'up' behavior, pcihp code will need to know in which mode it runs add 'legacy_piix' field to AcpiPciHpState structure and alter register behavior accordingly. Signed-off-by: Igor Mammedov Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/acpi/pcihp.c | 7 +++++-- hw/acpi/piix4.c | 3 ++- 2 files changed, 7 insertions(+), 3 deletions(-) (limited to 'hw/acpi') diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c index 64c8cf28f1..974f01c114 100644 --- a/hw/acpi/pcihp.c +++ b/hw/acpi/pcihp.c @@ -215,7 +215,9 @@ static uint64_t pci_read(void *opaque, hwaddr addr, unsigned int size) switch (addr) { case PCI_UP_BASE: val = s->acpi_pcihp_pci_status[bsel].up; - s->acpi_pcihp_pci_status[bsel].up = 0; + if (!s->legacy_piix) { + s->acpi_pcihp_pci_status[bsel].up = 0; + } ACPI_PCIHP_DPRINTF("pci_up_read %" PRIu32 "\n", val); break; case PCI_DOWN_BASE: @@ -273,9 +275,10 @@ static const MemoryRegionOps acpi_pcihp_io_ops = { }; void acpi_pcihp_init(AcpiPciHpState *s, PCIBus *root_bus, - MemoryRegion *address_space_io) + MemoryRegion *address_space_io, bool bridges_enabled) { s->root= root_bus; + s->legacy_piix = !bridges_enabled; memory_region_init_io(&s->io, NULL, &acpi_pcihp_io_ops, s, "acpi-pci-hotplug", PCI_HOTPLUG_SIZE); diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c index 5d55a3c222..2aedfe5998 100644 --- a/hw/acpi/piix4.c +++ b/hw/acpi/piix4.c @@ -695,7 +695,8 @@ static void piix4_acpi_system_hot_add_init(MemoryRegion *parent, memory_region_add_subregion(parent, GPE_BASE, &s->io_gpe); if (s->use_acpi_pci_hotplug) { - acpi_pcihp_init(&s->acpi_pci_hotplug, bus, parent); + acpi_pcihp_init(&s->acpi_pci_hotplug, bus, parent, + s->use_acpi_pci_hotplug); } else { memory_region_init_io(&s->io_pci, OBJECT(s), &piix4_pci_ops, s, "acpi-pci-hotplug", PCI_HOTPLUG_SIZE); -- cgit v1.2.3