[PATCH edk2-platforms 2/3] WIP: SbsaQemu: make PCIe variables dynamic (part 2)

["Marcin Juszkiewicz" <marcin.juszkiewicz@linaro.org>]

Create MCFG table directly from C code instead of ASLC as we cannot use
FixedPcd* for PCIe data.
---
 .../Qemu/SbsaQemu/AcpiTables/AcpiTables.inf   |  1 -
 .../SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.inf       |  9 +++
 .../Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c | 74 +++++++++++++++++++
 Silicon/Qemu/SbsaQemu/AcpiTables/Mcfg.aslc    | 43 -----------
 4 files changed, 83 insertions(+), 44 deletions(-)
 delete mode 100644 Silicon/Qemu/SbsaQemu/AcpiTables/Mcfg.aslc

diff --git a/Silicon/Qemu/SbsaQemu/AcpiTables/AcpiTables.inf b/Silicon/Qemu/SbsaQemu/AcpiTables/AcpiTables.inf
index 0501c670d565..5607878c2040 100644
--- a/Silicon/Qemu/SbsaQemu/AcpiTables/AcpiTables.inf
+++ b/Silicon/Qemu/SbsaQemu/AcpiTables/AcpiTables.inf
@@ -20,7 +20,6 @@ [Sources]
   Dsdt.asl
   Fadt.aslc
   Gtdt.aslc
-  Mcfg.aslc
   Spcr.aslc
 
 [Packages]
diff --git a/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.inf b/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.inf
index c1c33788567d..aad4c8086c40 100644
--- a/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.inf
+++ b/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.inf
@@ -43,11 +43,20 @@ [LibraryClasses]
 
 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdAcpiTableStorageFile
+  gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress
   gArmVirtSbsaQemuPlatformTokenSpaceGuid.PcdCoreCount
   gArmVirtSbsaQemuPlatformTokenSpaceGuid.PcdClusterCount
 
   gArmTokenSpaceGuid.PcdGicDistributorBase
   gArmTokenSpaceGuid.PcdGicRedistributorsBase
+  gArmTokenSpaceGuid.PcdPciBusMin
+  gArmTokenSpaceGuid.PcdPciBusMax
+  gArmTokenSpaceGuid.PcdPciIoBase
+  gArmTokenSpaceGuid.PcdPciIoSize
+  gArmTokenSpaceGuid.PcdPciMmio32Base
+  gArmTokenSpaceGuid.PcdPciMmio32Size
+  gArmTokenSpaceGuid.PcdPciMmio64Base
+  gArmTokenSpaceGuid.PcdPciMmio64Size
 
 [Depex]
   gEfiAcpiTableProtocolGuid                       ## CONSUMES
diff --git a/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c b/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c
index ae5397bab768..af95f7e14672 100644
--- a/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c
+++ b/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c
@@ -8,6 +8,7 @@
 **/
 #include <IndustryStandard/Acpi.h>
 #include <IndustryStandard/AcpiAml.h>
+#include <IndustryStandard/MemoryMappedConfigurationSpaceAccessTable.h>
 #include <IndustryStandard/SbsaQemuAcpi.h>
 #include <Library/AcpiLib.h>
 #include <Library/BaseMemoryLib.h>
@@ -306,6 +307,74 @@ AddSsdtTable (
   return Status;
 }
 
+/*
+ * A function that adds the MCFG ACPI table.
+ */
+EFI_STATUS
+AddMcfgTable (
+  IN EFI_ACPI_TABLE_PROTOCOL   *AcpiTable
+  )
+{
+  EFI_STATUS            Status;
+  UINTN                 TableHandle;
+  UINT32                TableSize;
+  EFI_PHYSICAL_ADDRESS  PageAddress;
+  UINT8                 *New;
+
+  EFI_ACPI_DESCRIPTION_HEADER Header =
+    SBSAQEMU_ACPI_HEADER (
+      EFI_ACPI_6_5_PCI_EXPRESS_MEMORY_MAPPED_CONFIGURATION_SPACE_BASE_ADDRESS_DESCRIPTION_TABLE_SIGNATURE,
+      EFI_ACPI_DESCRIPTION_HEADER,
+      EFI_ACPI_MEMORY_MAPPED_CONFIGURATION_SPACE_ACCESS_TABLE_REVISION);
+
+  TableSize = sizeof (EFI_ACPI_MEMORY_MAPPED_CONFIGURATION_BASE_ADDRESS_TABLE_HEADER) +
+	      sizeof(EFI_ACPI_MEMORY_MAPPED_ENHANCED_CONFIGURATION_SPACE_BASE_ADDRESS_ALLOCATION_STRUCTURE);
+
+  Status = gBS->AllocatePages (
+                  AllocateAnyPages,
+                  EfiACPIReclaimMemory,
+                  EFI_SIZE_TO_PAGES (TableSize),
+                  &PageAddress
+                  );
+  if (EFI_ERROR(Status)) {
+    DEBUG ((DEBUG_ERROR, "Failed to allocate pages for MCFG table\n"));
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  New = (UINT8 *)(UINTN) PageAddress;
+  ZeroMem (New, TableSize);
+
+  Header.Length = TableSize;
+
+  // Add the ACPI Description table header
+  CopyMem (New, &Header, sizeof (EFI_ACPI_DESCRIPTION_HEADER));
+  New += sizeof (EFI_ACPI_MEMORY_MAPPED_CONFIGURATION_BASE_ADDRESS_TABLE_HEADER);
+
+  EFI_ACPI_MEMORY_MAPPED_ENHANCED_CONFIGURATION_SPACE_BASE_ADDRESS_ALLOCATION_STRUCTURE  *CfgPtr;
+
+  CfgPtr = (VOID *)New;
+
+  CfgPtr->BaseAddress    = PcdGet64 (PcdPciExpressBaseAddress);
+  CfgPtr->StartBusNumber = PcdGet32 (PcdPciBusMin);
+  CfgPtr->EndBusNumber   = PcdGet32 (PcdPciBusMax);
+  CfgPtr->PciSegmentGroupNumber = 0;
+
+  // Perform Checksum
+  AcpiPlatformChecksum ((UINT8*) PageAddress, TableSize);
+
+  Status = AcpiTable->InstallAcpiTable (
+                        AcpiTable,
+                        (EFI_ACPI_COMMON_HEADER *)PageAddress,
+                        TableSize,
+                        &TableHandle
+                        );
+  if (EFI_ERROR(Status)) {
+    DEBUG ((DEBUG_ERROR, "Failed to install MCFG table\n"));
+  }
+
+  return Status;
+}
+
 /*
  * A function that adds the SSDT ACPI table.
  */
@@ -443,6 +512,11 @@ InitializeSbsaQemuAcpiDxe (
      DEBUG ((DEBUG_ERROR, "Failed to add MADT table\n"));
   }
 
+  Status = AddMcfgTable (AcpiTable);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "Failed to add MCFG table\n"));
+  }
+
   Status = AddSsdtTable (AcpiTable);
   if (EFI_ERROR(Status)) {
      DEBUG ((DEBUG_ERROR, "Failed to add SSDT table\n"));
diff --git a/Silicon/Qemu/SbsaQemu/AcpiTables/Mcfg.aslc b/Silicon/Qemu/SbsaQemu/AcpiTables/Mcfg.aslc
deleted file mode 100644
index 289f4ad4ea3a..000000000000
--- a/Silicon/Qemu/SbsaQemu/AcpiTables/Mcfg.aslc
+++ /dev/null
@@ -1,43 +0,0 @@
-/** @file
-*  ACPI Memory mapped configuration space base address Description Table (MCFG).
-*
-*  Copyright (c) 2020, Linaro Limited. All rights reserved.
-*
-*  SPDX-License-Identifier: BSD-2-Clause-Patent
-**/
-
-#include <IndustryStandard/Acpi.h>
-#include <IndustryStandard/MemoryMappedConfigurationSpaceAccessTable.h>
-#include <IndustryStandard/SbsaQemuAcpi.h>
-
-#pragma pack(push, 1)
-
-typedef struct {
-  EFI_ACPI_MEMORY_MAPPED_CONFIGURATION_BASE_ADDRESS_TABLE_HEADER Header;
-  EFI_ACPI_MEMORY_MAPPED_ENHANCED_CONFIGURATION_SPACE_BASE_ADDRESS_ALLOCATION_STRUCTURE Structure[1];
-} EFI_ACPI_MEMORY_MAPPED_CONFIGURATION_SPACE_ACCESS_DESCRIPTION_TABLE;
-
-EFI_ACPI_MEMORY_MAPPED_CONFIGURATION_SPACE_ACCESS_DESCRIPTION_TABLE Mcfg = {
-  {
-    SBSAQEMU_ACPI_HEADER (
-      EFI_ACPI_6_0_PCI_EXPRESS_MEMORY_MAPPED_CONFIGURATION_SPACE_BASE_ADDRESS_DESCRIPTION_TABLE_SIGNATURE,
-      EFI_ACPI_MEMORY_MAPPED_CONFIGURATION_SPACE_ACCESS_DESCRIPTION_TABLE,
-      EFI_ACPI_MEMORY_MAPPED_CONFIGURATION_SPACE_ACCESS_TABLE_REVISION),
-    EFI_ACPI_RESERVED_QWORD
-  },
-  {
-    {
-      FixedPcdGet32 (PcdPciExpressBaseAddress),
-      0,
-      FixedPcdGet32 (PcdPciBusMin),
-      FixedPcdGet32 (PcdPciBusMax),
-      EFI_ACPI_RESERVED_DWORD
-    }
-  }
-};
-
-#pragma pack(pop)
-
-// Reference the table being generated to prevent the optimizer
-// from removing the data structure from the executable
-VOID* CONST ReferenceAcpiTable = &Mcfg;
-- 
2.40.1