OvmfPkg: PciHostBridgeLib: set RootBus->Segment

[mirror_edk2.git] / OvmfPkg / Library / PciHostBridgeLib / PciHostBridgeLib.c

/** @file\r
  OVMF's instance of the PCI Host Bridge Library.\r
\r
  Copyright (C) 2016, Red Hat, Inc.\r
  Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>\r
\r
  This program and the accompanying materials are licensed and made available\r
  under the terms and conditions of the BSD License which accompanies this\r
  distribution.  The full text of the license may be found at\r
  http://opensource.org/licenses/bsd-license.php.\r
\r
  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT\r
  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
**/\r
#include <PiDxe.h>\r
\r
#include <IndustryStandard/Pci.h>\r
\r
#include <Library/BaseMemoryLib.h>\r
#include <Library/DebugLib.h>\r
#include <Library/MemoryAllocationLib.h>\r
#include <Library/PciHostBridgeLib.h>\r
#include <Library/PciLib.h>\r
#include <Library/QemuFwCfgLib.h>\r
\r
\r
GLOBAL_REMOVE_IF_UNREFERENCED\r
CHAR16 *mPciHostBridgeLibAcpiAddressSpaceTypeStr[] = {\r
  L"Mem", L"I/O", L"Bus"\r
};\r
\r
\r
/**\r
  Initialize a PCI_ROOT_BRIDGE structure.\r
\r
  param[in]  RootBusNumber     The bus number to store in RootBus.\r
\r
  param[in]  MaxSubBusNumber   The inclusive maximum bus number that can be\r
                               assigned to any subordinate bus found behind any\r
                               PCI bridge hanging off this root bus.\r
\r
                               The caller is repsonsible for ensuring that\r
                               RootBusNumber <= MaxSubBusNumber. If\r
                               RootBusNumber equals MaxSubBusNumber, then the\r
                               root bus has no room for subordinate buses.\r
\r
  param[out] RootBus           The PCI_ROOT_BRIDGE structure (allocated by the\r
                               caller) that should be filled in by this\r
                               function.\r
\r
  @retval EFI_SUCCESS           Initialization successful. A device path\r
                                consisting of an ACPI device path node, with\r
                                UID = RootBusNumber, has been allocated and\r
                                linked into RootBus.\r
\r
  @retval EFI_OUT_OF_RESOURCES  Memory allocation failed.\r
**/\r
STATIC\r
EFI_STATUS\r
InitRootBridge (\r
  IN  UINT8           RootBusNumber,\r
  IN  UINT8           MaxSubBusNumber,\r
  OUT PCI_ROOT_BRIDGE *RootBus\r
  )\r
{\r
  //\r
  // Be safe if other fields are added to PCI_ROOT_BRIDGE later.\r
  //\r
  ZeroMem (RootBus, sizeof *RootBus);\r
\r
  RootBus->Segment = 0;\r
\r
  return EFI_OUT_OF_RESOURCES;\r
}\r
\r
\r
/**\r
  Uninitialize a PCI_ROOT_BRIDGE structure set up with InitRootBridge().\r
\r
  param[in] RootBus  The PCI_ROOT_BRIDGE structure, allocated by the caller and\r
                     initialized with InitRootBridge(), that should be\r
                     uninitialized. This function doesn't free RootBus.\r
**/\r
STATIC\r
VOID\r
UninitRootBridge (\r
  IN PCI_ROOT_BRIDGE *RootBus\r
  )\r
{\r
}\r
\r
\r
/**\r
  Return all the root bridge instances in an array.\r
\r
  @param Count  Return the count of root bridge instances.\r
\r
  @return All the root bridge instances in an array.\r
          The array should be passed into PciHostBridgeFreeRootBridges()\r
          when it's not used.\r
**/\r
PCI_ROOT_BRIDGE *\r
EFIAPI\r
PciHostBridgeGetRootBridges (\r
  UINTN *Count\r
  )\r
{\r
  EFI_STATUS           Status;\r
  FIRMWARE_CONFIG_ITEM FwCfgItem;\r
  UINTN                FwCfgSize;\r
  UINT64               ExtraRootBridges;\r
  PCI_ROOT_BRIDGE      *Bridges;\r
  UINTN                Initialized;\r
  UINTN                LastRootBridgeNumber;\r
  UINTN                RootBridgeNumber;\r
\r
  *Count = 0;\r
\r
  //\r
  // QEMU provides the number of extra root buses, shortening the exhaustive\r
  // search below. If there is no hint, the feature is missing.\r
  //\r
  Status = QemuFwCfgFindFile ("etc/extra-pci-roots", &FwCfgItem, &FwCfgSize);\r
  if (EFI_ERROR (Status) || FwCfgSize != sizeof ExtraRootBridges) {\r
    ExtraRootBridges = 0;\r
  } else {\r
    QemuFwCfgSelectItem (FwCfgItem);\r
    QemuFwCfgReadBytes (FwCfgSize, &ExtraRootBridges);\r
\r
    if (ExtraRootBridges > PCI_MAX_BUS) {\r
      DEBUG ((EFI_D_ERROR, "%a: invalid count of extra root buses (%Lu) "\r
        "reported by QEMU\n", __FUNCTION__, ExtraRootBridges));\r
      return NULL;\r
    }\r
    DEBUG ((EFI_D_INFO, "%a: %Lu extra root buses reported by QEMU\n",\r
      __FUNCTION__, ExtraRootBridges));\r
  }\r
\r
  //\r
  // Allocate the "main" root bridge, and any extra root bridges.\r
  //\r
  Bridges = AllocatePool ((1 + (UINTN)ExtraRootBridges) * sizeof *Bridges);\r
  if (Bridges == NULL) {\r
    DEBUG ((EFI_D_ERROR, "%a: %r\n", __FUNCTION__, EFI_OUT_OF_RESOURCES));\r
    return NULL;\r
  }\r
  Initialized = 0;\r
\r
  //\r
  // The "main" root bus is always there.\r
  //\r
  LastRootBridgeNumber = 0;\r
\r
  //\r
  // Scan all other root buses. If function 0 of any device on a bus returns a\r
  // VendorId register value different from all-bits-one, then that bus is\r
  // alive.\r
  //\r
  for (RootBridgeNumber = 1;\r
       RootBridgeNumber <= PCI_MAX_BUS && Initialized < ExtraRootBridges;\r
       ++RootBridgeNumber) {\r
    UINTN Device;\r
\r
    for (Device = 0; Device <= PCI_MAX_DEVICE; ++Device) {\r
      if (PciRead16 (PCI_LIB_ADDRESS (RootBridgeNumber, Device, 0,\r
                       PCI_VENDOR_ID_OFFSET)) != MAX_UINT16) {\r
        break;\r
      }\r
    }\r
    if (Device <= PCI_MAX_DEVICE) {\r
      //\r
      // Found the next root bus. We can now install the *previous* one,\r
      // because now we know how big a bus number range *that* one has, for any\r
      // subordinate buses that might exist behind PCI bridges hanging off it.\r
      //\r
      Status = InitRootBridge ((UINT8)LastRootBridgeNumber,\r
                 (UINT8)(RootBridgeNumber - 1), &Bridges[Initialized]);\r
      if (EFI_ERROR (Status)) {\r
        goto FreeBridges;\r
      }\r
      ++Initialized;\r
      LastRootBridgeNumber = RootBridgeNumber;\r
    }\r
  }\r
\r
  //\r
  // Install the last root bus (which might be the only, ie. main, root bus, if\r
  // we've found no extra root buses).\r
  //\r
  Status = InitRootBridge ((UINT8)LastRootBridgeNumber, PCI_MAX_BUS,\r
             &Bridges[Initialized]);\r
  if (EFI_ERROR (Status)) {\r
    goto FreeBridges;\r
  }\r
  ++Initialized;\r
\r
  *Count = Initialized;\r
  return Bridges;\r
\r
FreeBridges:\r
  while (Initialized > 0) {\r
    --Initialized;\r
    UninitRootBridge (&Bridges[Initialized]);\r
  }\r
\r
  FreePool (Bridges);\r
  return NULL;\r
}\r
\r
\r
/**\r
  Free the root bridge instances array returned from\r
  PciHostBridgeGetRootBridges().\r
\r
  @param  The root bridge instances array.\r
  @param  The count of the array.\r
**/\r
VOID\r
EFIAPI\r
PciHostBridgeFreeRootBridges (\r
  PCI_ROOT_BRIDGE *Bridges,\r
  UINTN           Count\r
  )\r
{\r
  if (Bridges == NULL && Count == 0) {\r
    return;\r
  }\r
  ASSERT (Bridges != NULL && Count > 0);\r
\r
  do {\r
    --Count;\r
    UninitRootBridge (&Bridges[Count]);\r
  } while (Count > 0);\r
\r
  FreePool (Bridges);\r
}\r
\r
\r
/**\r
  Inform the platform that the resource conflict happens.\r
\r
  @param HostBridgeHandle Handle of the Host Bridge.\r
  @param Configuration    Pointer to PCI I/O and PCI memory resource\r
                          descriptors. The Configuration contains the resources\r
                          for all the root bridges. The resource for each root\r
                          bridge is terminated with END descriptor and an\r
                          additional END is appended indicating the end of the\r
                          entire resources. The resource descriptor field\r
                          values follow the description in\r
                          EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL\r
                          .SubmitResources().\r
**/\r
VOID\r
EFIAPI\r
PciHostBridgeResourceConflict (\r
  EFI_HANDLE                        HostBridgeHandle,\r
  VOID                              *Configuration\r
  )\r
{\r
  EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *Descriptor;\r
  UINTN                             RootBridgeIndex;\r
  DEBUG ((EFI_D_ERROR, "PciHostBridge: Resource conflict happens!\n"));\r
\r
  RootBridgeIndex = 0;\r
  Descriptor = (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Configuration;\r
  while (Descriptor->Desc == ACPI_ADDRESS_SPACE_DESCRIPTOR) {\r
    DEBUG ((EFI_D_ERROR, "RootBridge[%d]:\n", RootBridgeIndex++));\r
    for (; Descriptor->Desc == ACPI_ADDRESS_SPACE_DESCRIPTOR; Descriptor++) {\r
      ASSERT (Descriptor->ResType <\r
              (sizeof (mPciHostBridgeLibAcpiAddressSpaceTypeStr) /\r
               sizeof (mPciHostBridgeLibAcpiAddressSpaceTypeStr[0])\r
               )\r
              );\r
      DEBUG ((EFI_D_ERROR, " %s: Length/Alignment = 0x%lx / 0x%lx\n",\r
              mPciHostBridgeLibAcpiAddressSpaceTypeStr[Descriptor->ResType],\r
              Descriptor->AddrLen, Descriptor->AddrRangeMax\r
              ));\r
      if (Descriptor->ResType == ACPI_ADDRESS_SPACE_TYPE_MEM) {\r
        DEBUG ((EFI_D_ERROR, "     Granularity/SpecificFlag = %ld / %02x%s\n",\r
                Descriptor->AddrSpaceGranularity, Descriptor->SpecificFlag,\r
                ((Descriptor->SpecificFlag &\r
                  EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE\r
                  ) != 0) ? L" (Prefetchable)" : L""\r
                ));\r
      }\r
    }\r
    //\r
    // Skip the END descriptor for root bridge\r
    //\r
    ASSERT (Descriptor->Desc == ACPI_END_TAG_DESCRIPTOR);\r
    Descriptor = (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)(\r
                   (EFI_ACPI_END_TAG_DESCRIPTOR *)Descriptor + 1\r
                   );\r
  }\r
}\r