2 OVMF's instance of the PCI Host Bridge Library.
4 Copyright (C) 2016, Red Hat, Inc.
5 Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
7 This program and the accompanying materials are licensed and made available
8 under the terms and conditions of the BSD License which accompanies this
9 distribution. The full text of the license may be found at
10 http://opensource.org/licenses/bsd-license.php.
12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
13 WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
18 #include <IndustryStandard/Pci.h>
20 #include <Library/DebugLib.h>
21 #include <Library/MemoryAllocationLib.h>
22 #include <Library/PciHostBridgeLib.h>
23 #include <Library/PciLib.h>
24 #include <Library/QemuFwCfgLib.h>
27 GLOBAL_REMOVE_IF_UNREFERENCED
28 CHAR16
*mPciHostBridgeLibAcpiAddressSpaceTypeStr
[] = {
29 L
"Mem", L
"I/O", L
"Bus"
34 Initialize a PCI_ROOT_BRIDGE structure.
36 param[in] RootBusNumber The bus number to store in RootBus.
38 param[in] MaxSubBusNumber The inclusive maximum bus number that can be
39 assigned to any subordinate bus found behind any
40 PCI bridge hanging off this root bus.
42 The caller is repsonsible for ensuring that
43 RootBusNumber <= MaxSubBusNumber. If
44 RootBusNumber equals MaxSubBusNumber, then the
45 root bus has no room for subordinate buses.
47 param[out] RootBus The PCI_ROOT_BRIDGE structure (allocated by the
48 caller) that should be filled in by this
51 @retval EFI_SUCCESS Initialization successful. A device path
52 consisting of an ACPI device path node, with
53 UID = RootBusNumber, has been allocated and
56 @retval EFI_OUT_OF_RESOURCES Memory allocation failed.
61 IN UINT8 RootBusNumber
,
62 IN UINT8 MaxSubBusNumber
,
63 OUT PCI_ROOT_BRIDGE
*RootBus
66 return EFI_OUT_OF_RESOURCES
;
71 Uninitialize a PCI_ROOT_BRIDGE structure set up with InitRootBridge().
73 param[in] RootBus The PCI_ROOT_BRIDGE structure, allocated by the caller and
74 initialized with InitRootBridge(), that should be
75 uninitialized. This function doesn't free RootBus.
80 IN PCI_ROOT_BRIDGE
*RootBus
87 Return all the root bridge instances in an array.
89 @param Count Return the count of root bridge instances.
91 @return All the root bridge instances in an array.
92 The array should be passed into PciHostBridgeFreeRootBridges()
97 PciHostBridgeGetRootBridges (
102 FIRMWARE_CONFIG_ITEM FwCfgItem
;
104 UINT64 ExtraRootBridges
;
105 PCI_ROOT_BRIDGE
*Bridges
;
107 UINTN LastRootBridgeNumber
;
108 UINTN RootBridgeNumber
;
113 // QEMU provides the number of extra root buses, shortening the exhaustive
114 // search below. If there is no hint, the feature is missing.
116 Status
= QemuFwCfgFindFile ("etc/extra-pci-roots", &FwCfgItem
, &FwCfgSize
);
117 if (EFI_ERROR (Status
) || FwCfgSize
!= sizeof ExtraRootBridges
) {
118 ExtraRootBridges
= 0;
120 QemuFwCfgSelectItem (FwCfgItem
);
121 QemuFwCfgReadBytes (FwCfgSize
, &ExtraRootBridges
);
123 if (ExtraRootBridges
> PCI_MAX_BUS
) {
124 DEBUG ((EFI_D_ERROR
, "%a: invalid count of extra root buses (%Lu) "
125 "reported by QEMU\n", __FUNCTION__
, ExtraRootBridges
));
128 DEBUG ((EFI_D_INFO
, "%a: %Lu extra root buses reported by QEMU\n",
129 __FUNCTION__
, ExtraRootBridges
));
133 // Allocate the "main" root bridge, and any extra root bridges.
135 Bridges
= AllocatePool ((1 + (UINTN
)ExtraRootBridges
) * sizeof *Bridges
);
136 if (Bridges
== NULL
) {
137 DEBUG ((EFI_D_ERROR
, "%a: %r\n", __FUNCTION__
, EFI_OUT_OF_RESOURCES
));
143 // The "main" root bus is always there.
145 LastRootBridgeNumber
= 0;
148 // Scan all other root buses. If function 0 of any device on a bus returns a
149 // VendorId register value different from all-bits-one, then that bus is
152 for (RootBridgeNumber
= 1;
153 RootBridgeNumber
<= PCI_MAX_BUS
&& Initialized
< ExtraRootBridges
;
154 ++RootBridgeNumber
) {
157 for (Device
= 0; Device
<= PCI_MAX_DEVICE
; ++Device
) {
158 if (PciRead16 (PCI_LIB_ADDRESS (RootBridgeNumber
, Device
, 0,
159 PCI_VENDOR_ID_OFFSET
)) != MAX_UINT16
) {
163 if (Device
<= PCI_MAX_DEVICE
) {
165 // Found the next root bus. We can now install the *previous* one,
166 // because now we know how big a bus number range *that* one has, for any
167 // subordinate buses that might exist behind PCI bridges hanging off it.
169 Status
= InitRootBridge ((UINT8
)LastRootBridgeNumber
,
170 (UINT8
)(RootBridgeNumber
- 1), &Bridges
[Initialized
]);
171 if (EFI_ERROR (Status
)) {
175 LastRootBridgeNumber
= RootBridgeNumber
;
180 // Install the last root bus (which might be the only, ie. main, root bus, if
181 // we've found no extra root buses).
183 Status
= InitRootBridge ((UINT8
)LastRootBridgeNumber
, PCI_MAX_BUS
,
184 &Bridges
[Initialized
]);
185 if (EFI_ERROR (Status
)) {
190 *Count
= Initialized
;
194 while (Initialized
> 0) {
196 UninitRootBridge (&Bridges
[Initialized
]);
205 Free the root bridge instances array returned from
206 PciHostBridgeGetRootBridges().
208 @param The root bridge instances array.
209 @param The count of the array.
213 PciHostBridgeFreeRootBridges (
214 PCI_ROOT_BRIDGE
*Bridges
,
218 if (Bridges
== NULL
&& Count
== 0) {
221 ASSERT (Bridges
!= NULL
&& Count
> 0);
225 UninitRootBridge (&Bridges
[Count
]);
233 Inform the platform that the resource conflict happens.
235 @param HostBridgeHandle Handle of the Host Bridge.
236 @param Configuration Pointer to PCI I/O and PCI memory resource
237 descriptors. The Configuration contains the resources
238 for all the root bridges. The resource for each root
239 bridge is terminated with END descriptor and an
240 additional END is appended indicating the end of the
241 entire resources. The resource descriptor field
242 values follow the description in
243 EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL
248 PciHostBridgeResourceConflict (
249 EFI_HANDLE HostBridgeHandle
,
253 EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR
*Descriptor
;
254 UINTN RootBridgeIndex
;
255 DEBUG ((EFI_D_ERROR
, "PciHostBridge: Resource conflict happens!\n"));
258 Descriptor
= (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR
*) Configuration
;
259 while (Descriptor
->Desc
== ACPI_ADDRESS_SPACE_DESCRIPTOR
) {
260 DEBUG ((EFI_D_ERROR
, "RootBridge[%d]:\n", RootBridgeIndex
++));
261 for (; Descriptor
->Desc
== ACPI_ADDRESS_SPACE_DESCRIPTOR
; Descriptor
++) {
262 ASSERT (Descriptor
->ResType
<
263 (sizeof (mPciHostBridgeLibAcpiAddressSpaceTypeStr
) /
264 sizeof (mPciHostBridgeLibAcpiAddressSpaceTypeStr
[0])
267 DEBUG ((EFI_D_ERROR
, " %s: Length/Alignment = 0x%lx / 0x%lx\n",
268 mPciHostBridgeLibAcpiAddressSpaceTypeStr
[Descriptor
->ResType
],
269 Descriptor
->AddrLen
, Descriptor
->AddrRangeMax
271 if (Descriptor
->ResType
== ACPI_ADDRESS_SPACE_TYPE_MEM
) {
272 DEBUG ((EFI_D_ERROR
, " Granularity/SpecificFlag = %ld / %02x%s\n",
273 Descriptor
->AddrSpaceGranularity
, Descriptor
->SpecificFlag
,
274 ((Descriptor
->SpecificFlag
&
275 EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE
276 ) != 0) ? L
" (Prefetchable)" : L
""
281 // Skip the END descriptor for root bridge
283 ASSERT (Descriptor
->Desc
== ACPI_END_TAG_DESCRIPTOR
);
284 Descriptor
= (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR
*)(
285 (EFI_ACPI_END_TAG_DESCRIPTOR
*)Descriptor
+ 1