[PATCH RFC v2 02/12] hw/pci: Determine if rombar is explicitly enabled

[Akihiko Odaki <akihiko.odaki@daynix.com>]

vfio determines if rombar is explicitly enabled by inspecting QDict.
Inspecting QDict is not nice because QDict is untyped and depends on the
details on the external interface. Add an infrastructure to determine if
rombar is explicitly enabled to hw/pci. PCIDevice::rom_bar is changed to
have -1 by the default to tell rombar is explicitly enabled. It is
consistent with other properties like addr and romsize.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 include/hw/pci/pci_device.h | 5 +++++
 hw/pci/pci.c                | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/include/hw/pci/pci_device.h b/include/hw/pci/pci_device.h
index d3dd0f64b2..54fa0676ab 100644
--- a/include/hw/pci/pci_device.h
+++ b/include/hw/pci/pci_device.h
@@ -205,6 +205,11 @@ static inline uint16_t pci_get_bdf(PCIDevice *dev)
     return PCI_BUILD_BDF(pci_bus_num(pci_get_bus(dev)), dev->devfn);
 }
 
+static inline bool pci_rom_bar_explicitly_enabled(PCIDevice *dev)
+{
+    return dev->rom_bar && dev->rom_bar != -1;
+}
+
 uint16_t pci_requester_id(PCIDevice *dev);
 
 /* DMA access functions */
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 4cf31128ba..31e8f413a6 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -71,7 +71,7 @@ static Property pci_props[] = {
     DEFINE_PROP_PCI_DEVFN("addr", PCIDevice, devfn, -1),
     DEFINE_PROP_STRING("romfile", PCIDevice, romfile),
     DEFINE_PROP_UINT32("romsize", PCIDevice, romsize, -1),
-    DEFINE_PROP_UINT32("rombar",  PCIDevice, rom_bar, 1),
+    DEFINE_PROP_UINT32("rombar",  PCIDevice, rom_bar, -1),
     DEFINE_PROP_BIT("multifunction", PCIDevice, cap_present,
                     QEMU_PCI_CAP_MULTIFUNCTION_BITNR, false),
     DEFINE_PROP_BIT("x-pcie-lnksta-dllla", PCIDevice, cap_present,

-- 
2.43.0