OvmfPkg: Install ACPI tables for Cloud Hypervisor

Adding support for retrieving the Cloud Hypervisor ACPI tables as a
fallback mechanism if tables are not found through fw_cfg.

Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

OvmfPkg/AcpiPlatformDxe/AcpiPlatform.c

@@ -7,6 +7,8 @@
   SPDX-License-Identifier: BSD-2-Clause-Patent
 **/
 
+#include <OvmfPlatforms.h> // CLOUDHV_DEVICE_ID
+
 #include "AcpiPlatform.h"
 
 /**
@@ -27,7 +29,14 @@ InstallAcpiTables (
   )
 {
   EFI_STATUS  Status;
+  UINT16      HostBridgeDevId;
 
+  HostBridgeDevId = PcdGet16 (PcdOvmfHostBridgePciDevId);
+  if (HostBridgeDevId == CLOUDHV_DEVICE_ID) {
+    Status = InstallCloudHvTables (AcpiTable);
+  } else {
     Status = InstallQemuFwCfgTables (AcpiTable);
+  }
+
   return Status;
 }

OvmfPkg/AcpiPlatformDxe/AcpiPlatform.h

@@ -19,6 +19,12 @@ typedef struct {
 
 typedef struct S3_CONTEXT S3_CONTEXT;
 
+EFI_STATUS
+EFIAPI
+InstallCloudHvTables (
+  IN   EFI_ACPI_TABLE_PROTOCOL  *AcpiProtocol
+  );
+
 EFI_STATUS
 EFIAPI
 InstallQemuFwCfgTables (

OvmfPkg/AcpiPlatformDxe/AcpiPlatformDxe.inf

@@ -24,6 +24,7 @@
   AcpiPlatform.c
   AcpiPlatform.h
   BootScript.c
+  CloudHvAcpi.c
   EntryPoint.c
   PciDecoding.c
   QemuFwCfgAcpi.c
@@ -54,6 +55,7 @@
 
 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdPciDisableBusEnumeration
+  gUefiOvmfPkgTokenSpaceGuid.PcdOvmfHostBridgePciDevId
 
 [Depex]
   gEfiAcpiTableProtocolGuid

OvmfPkg/AcpiPlatformDxe/CloudHvAcpi.c

@@ -0,0 +1,118 @@
+/** @file
+  OVMF ACPI Cloud Hypervisor support
+
+  Copyright (c) 2021, Intel Corporation. All rights reserved.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <IndustryStandard/CloudHv.h> // CLOUDHV_RSDP_ADDRESS
+#include <Library/BaseLib.h>          // CpuDeadLoop()
+#include <Library/DebugLib.h>         // DEBUG()
+
+#include "AcpiPlatform.h"
+
+// Get the ACPI tables from EBDA start
+EFI_STATUS
+EFIAPI
+InstallCloudHvTables (
+  IN   EFI_ACPI_TABLE_PROTOCOL  *AcpiProtocol
+  )
+{
+  EFI_STATUS  Status;
+  UINTN       TableHandle;
+
+  EFI_ACPI_DESCRIPTION_HEADER                *Xsdt;
+  VOID                                       *CurrentTableEntry;
+  UINTN                                      CurrentTablePointer;
+  EFI_ACPI_DESCRIPTION_HEADER                *CurrentTable;
+  UINTN                                      Index;
+  UINTN                                      NumberOfTableEntries;
+  EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE  *Fadt2Table;
+  EFI_ACPI_DESCRIPTION_HEADER                *DsdtTable;
+
+  Fadt2Table           = NULL;
+  DsdtTable            = NULL;
+  TableHandle          = 0;
+  NumberOfTableEntries = 0;
+  EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER  *AcpiRsdpStructurePtr = (VOID *)CLOUDHV_RSDP_ADDRESS;
+
+  // If XSDT table is found, just install its tables.
+  // Otherwise, try to find and install the RSDT tables.
+  //
+  if (AcpiRsdpStructurePtr->XsdtAddress) {
+    //
+    // Retrieve the addresses of XSDT and
+    // calculate the number of its table entries.
+    //
+    Xsdt = (EFI_ACPI_DESCRIPTION_HEADER *)(UINTN)
+           AcpiRsdpStructurePtr->XsdtAddress;
+    NumberOfTableEntries = (Xsdt->Length -
+                            sizeof (EFI_ACPI_DESCRIPTION_HEADER)) /
+                           sizeof (UINT64);
+
+    //
+    // Install ACPI tables found in XSDT.
+    //
+    for (Index = 0; Index < NumberOfTableEntries; Index++) {
+      //
+      // Get the table entry from XSDT
+      //
+      CurrentTableEntry = (VOID *)((UINT8 *)Xsdt +
+                                   sizeof (EFI_ACPI_DESCRIPTION_HEADER) +
+                                   Index * sizeof (UINT64));
+      CurrentTablePointer = (UINTN)*(UINT64 *)CurrentTableEntry;
+      CurrentTable        = (EFI_ACPI_DESCRIPTION_HEADER *)CurrentTablePointer;
+
+      //
+      // Install the XSDT tables
+      //
+      Status = AcpiProtocol->InstallAcpiTable (
+                               AcpiProtocol,
+                               CurrentTable,
+                               CurrentTable->Length,
+                               &TableHandle
+                               );
+
+      if (EFI_ERROR (Status)) {
+        ASSERT_EFI_ERROR (Status);
+        return Status;
+      }
+
+      //
+      // Get the X-DSDT table address from the table FADT
+      //
+      if (!AsciiStrnCmp ((CHAR8 *)&CurrentTable->Signature, "FACP", 4)) {
+        Fadt2Table = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *)
+                     (UINTN)CurrentTablePointer;
+        DsdtTable = (EFI_ACPI_DESCRIPTION_HEADER *)(UINTN)Fadt2Table->XDsdt;
+      }
+    }
+  } else {
+    return EFI_NOT_FOUND;
+  }
+
+  //
+  // Install DSDT table. If we reached this point without finding the DSDT,
+  // then we're out of sync with the hypervisor, and cannot continue.
+  //
+  if (DsdtTable == NULL) {
+    DEBUG ((DEBUG_ERROR, "%a: no DSDT found\n", __FUNCTION__));
+    ASSERT (FALSE);
+    CpuDeadLoop ();
+  }
+
+  Status = AcpiProtocol->InstallAcpiTable (
+                           AcpiProtocol,
+                           DsdtTable,
+                           DsdtTable->Length,
+                           &TableHandle
+                           );
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  return EFI_SUCCESS;
+}

OvmfPkg/Include/IndustryStandard/CloudHv.h

@@ -38,4 +38,9 @@
 //
 #define CLOUDHV_SMBIOS_ADDRESS  0xf0000
 
+//
+// RSDP address
+//
+#define CLOUDHV_RSDP_ADDRESS  0xa0000
+
 #endif // __CLOUDHV_H__