diff options
Diffstat (limited to 'OvmfPkg/PciHostBridgeDxe/PciHostBridge.c')
| -rw-r--r-- | OvmfPkg/PciHostBridgeDxe/PciHostBridge.c | 95 |
1 files changed, 71 insertions, 24 deletions
diff --git a/OvmfPkg/PciHostBridgeDxe/PciHostBridge.c b/OvmfPkg/PciHostBridgeDxe/PciHostBridge.c index 7dda75f0d3..348664438d 100644 --- a/OvmfPkg/PciHostBridgeDxe/PciHostBridge.c +++ b/OvmfPkg/PciHostBridgeDxe/PciHostBridge.c @@ -43,14 +43,6 @@ EFI_PCI_ROOT_BRIDGE_DEVICE_PATH mRootBridgeDevicePathTemplate = { }
};
-//
-// Hard code: Root Bridge's resource aperture
-//
-
-PCI_ROOT_BRIDGE_RESOURCE_APERTURE mResAperture[1] = {
- {0, 0xff, 0x80000000, 0xffffffff, 0, 0xffff}
-};
-
EFI_HANDLE mDriverImageHandle;
PCI_HOST_BRIDGE_INSTANCE mPciHostBridgeInstanceTemplate = {
@@ -80,8 +72,15 @@ PCI_HOST_BRIDGE_INSTANCE mPciHostBridgeInstanceTemplate = { param[in] RootBusNumber The bus number of the root bus (root bridge) to
create.
- RootBusNumber is expected to fall into the valid
- offset range of mResAperture.
+
+ param[in] MaxSubBusNumber The inclusive maximum bus number that can be
+ assigned to any subordinate bus found behind any
+ PCI bridge hanging off this root bus.
+
+ The caller is repsonsible for ensuring that
+ RootBusNumber <= MaxSubBusNumber. If
+ RootBusNumber equals MaxSubBusNumber, then the
+ root bus has no room for subordinate buses.
param[in] HostBridgeHandle The EFI_HANDLE corresponding to the host bridge
that is the parent of the root bridge to create.
@@ -108,12 +107,16 @@ STATIC EFI_STATUS
InitRootBridge (
IN UINT8 RootBusNumber,
+ IN UINT8 MaxSubBusNumber,
IN EFI_HANDLE HostBridgeHandle,
OUT PCI_ROOT_BRIDGE_INSTANCE **RootBus
)
{
- PCI_ROOT_BRIDGE_INSTANCE *PrivateData;
- EFI_STATUS Status;
+ PCI_ROOT_BRIDGE_INSTANCE *PrivateData;
+ PCI_ROOT_BRIDGE_RESOURCE_APERTURE ResAperture;
+ EFI_STATUS Status;
+
+ ASSERT (RootBusNumber <= MaxSubBusNumber);
PrivateData = AllocateZeroPool (sizeof *PrivateData);
if (PrivateData == NULL) {
@@ -126,13 +129,18 @@ InitRootBridge ( sizeof mRootBridgeDevicePathTemplate);
PrivateData->DevicePath.AcpiDevicePath.UID = RootBusNumber;
+ ResAperture.BusBase = RootBusNumber;
+ ResAperture.BusLimit = MaxSubBusNumber;
+ ResAperture.MemBase = BASE_2GB;
+ ResAperture.MemLimit = BASE_4GB - 1;
+ ResAperture.IoBase = 0;
+ ResAperture.IoLimit = MAX_UINT16;
//
// The function call below allocates no resources and performs no actions
// that have to be rolled back on later failure. It always succeeds.
//
Status = RootBridgeConstructor (&PrivateData->Io, HostBridgeHandle,
- EFI_PCI_HOST_BRIDGE_COMBINE_MEM_PMEM,
- &mResAperture[RootBusNumber]);
+ EFI_PCI_HOST_BRIDGE_COMBINE_MEM_PMEM, &ResAperture);
ASSERT_EFI_ERROR (Status);
Status = gBS->InstallMultipleProtocolInterfaces (&PrivateData->Handle,
@@ -143,6 +151,9 @@ InitRootBridge ( goto FreePrivateData;
}
+ DEBUG ((EFI_D_INFO,
+ "%a: installed root bus %d, with room for %d subordinate bus(es)\n",
+ __FUNCTION__, RootBusNumber, MaxSubBusNumber - RootBusNumber));
*RootBus = PrivateData;
return EFI_SUCCESS;
@@ -196,6 +207,7 @@ InitializePciHostBridge ( )
{
EFI_STATUS Status;
+ UINTN LastRootBridgeNumber;
UINTN RootBridgeNumber;
PCI_HOST_BRIDGE_INSTANCE *HostBridge;
PCI_ROOT_BRIDGE_INSTANCE *RootBus;
@@ -224,20 +236,55 @@ InitializePciHostBridge ( goto FreeHostBridge;
}
- for (RootBridgeNumber = 0;
- RootBridgeNumber < 1;
+ //
+ // The "main" root bus is always there.
+ //
+ LastRootBridgeNumber = 0;
+
+ //
+ // Scan all other root buses. If function 0 of any device on a bus returns a
+ // VendorId register value different from all-bits-one, then that bus is
+ // alive.
+ //
+ for (RootBridgeNumber = 1;
+ RootBridgeNumber < 256;
++RootBridgeNumber) {
- Status = InitRootBridge (
- (UINT8)RootBridgeNumber,
- HostBridge->HostBridgeHandle,
- &RootBus
- );
- if (EFI_ERROR (Status)) {
- goto RollbackProtocols;
+ UINTN Device;
+
+ for (Device = 0; Device <= MAX_PCI_DEVICE_NUMBER; ++Device) {
+ if (PciRead16 (PCI_LIB_ADDRESS (RootBridgeNumber, Device, 0,
+ PCI_VENDOR_ID_OFFSET)) != MAX_UINT16) {
+ break;
+ }
+ }
+ if (Device <= MAX_PCI_DEVICE_NUMBER) {
+ //
+ // Found the next root bus. We can now install the *previous* one,
+ // because now we know how big a bus number range *that* one has, for any
+ // subordinate buses that might exist behind PCI bridges hanging off it.
+ //
+ Status = InitRootBridge ((UINT8)LastRootBridgeNumber,
+ (UINT8)(RootBridgeNumber - 1), HostBridge->HostBridgeHandle,
+ &RootBus);
+ if (EFI_ERROR (Status)) {
+ goto RollbackProtocols;
+ }
+ InsertTailList (&HostBridge->Head, &RootBus->Link);
+ LastRootBridgeNumber = RootBridgeNumber;
}
- InsertTailList (&HostBridge->Head, &RootBus->Link);
}
+ //
+ // Install the last root bus (which might be the only, ie. main, root bus, if
+ // we've found no extra root buses).
+ //
+ Status = InitRootBridge ((UINT8)LastRootBridgeNumber, 255,
+ HostBridge->HostBridgeHandle, &RootBus);
+ if (EFI_ERROR (Status)) {
+ goto RollbackProtocols;
+ }
+ InsertTailList (&HostBridge->Head, &RootBus->Link);
+
return EFI_SUCCESS;
RollbackProtocols:
|