[PATCH v2 1/2] ArmVirtPkg/FdtPciHostBridgeLib: map ECAM and I/O spaces in GCD memory map

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

Up until now, we have been getting away with not declaring the ECAM
and translated I/O spaces at all in the GCD memory map, simply because
we map the entire address space with device attributes in the early PEI
code, and so these regions will be mapped wherever they end up.

Now that we are about to make changes to how ArmVirtQemu reasons
about the size of the address space, it would be better to get rid
of this mapping of the entire address space, since it can get
arbitrarily large without real benefit.

So start by mapping the ECAM and translated I/O spaces explicitly,
instead of relying on the early PEI mapping.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.inf |  1 +
 ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.c   | 46 +++++++++++++++++++-
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.inf b/ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.inf
index 0995f4b7a156..4011336a353b 100644
--- a/ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.inf
+++ b/ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.inf
@@ -42,6 +42,7 @@ [Packages]
 [LibraryClasses]
   DebugLib
   DevicePathLib
+  DxeServicesTableLib
   MemoryAllocationLib
   PciPcdProducerLib
 
diff --git a/ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.c b/ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.c
index 5b9c887db35d..ba177353122e 100644
--- a/ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.c
+++ b/ArmVirtPkg/Library/FdtPciHostBridgeLib/FdtPciHostBridgeLib.c
@@ -17,6 +17,7 @@
 #include <Library/PciHostBridgeLib.h>
 #include <Library/DebugLib.h>
 #include <Library/DevicePathLib.h>
+#include <Library/DxeServicesTableLib.h>
 #include <Library/MemoryAllocationLib.h>
 #include <Library/PcdLib.h>
 #include <Library/UefiBootServicesTableLib.h>
@@ -82,6 +83,33 @@ typedef struct {
 #define DTB_PCI_HOST_RANGE_IO           BIT24
 #define DTB_PCI_HOST_RANGE_TYPEMASK     (BIT31 | BIT30 | BIT29 | BIT25 | BIT24)
 
+STATIC
+EFI_STATUS
+MapGcdMmioSpace (
+  IN    UINT64    Base,
+  IN    UINT64    Size
+  )
+{
+  EFI_STATUS    Status;
+
+  Status = gDS->AddMemorySpace (EfiGcdMemoryTypeMemoryMappedIo, Base, Size,
+                  EFI_MEMORY_UC);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_WARN,
+      "%a: failed to add GCD memory space for region [0x%Lx+0x%Lx)\n",
+      __FUNCTION__, Base, Size));
+    return Status;
+  }
+
+  Status = gDS->SetMemorySpaceAttributes (Base, Size, EFI_MEMORY_UC);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_WARN,
+      "%a: failed to set memory space attributes for region [0x%Lx+0x%Lx)\n",
+      __FUNCTION__, Base, Size));
+  }
+  return Status;
+}
+
 STATIC
 EFI_STATUS
 ProcessPciHost (
@@ -266,7 +294,23 @@ ProcessPciHost (
     "Io[0x%Lx+0x%Lx)@0x%Lx Mem32[0x%Lx+0x%Lx)@0x0 Mem64[0x%Lx+0x%Lx)@0x0\n",
     __FUNCTION__, ConfigBase, ConfigSize, *BusMin, *BusMax, *IoBase, *IoSize,
     IoTranslation, *Mmio32Base, *Mmio32Size, *Mmio64Base, *Mmio64Size));
-  return EFI_SUCCESS;
+
+  // Map the ECAM space in the GCD memory map
+  Status = MapGcdMmioSpace (ConfigBase, ConfigSize);
+  ASSERT_EFI_ERROR (Status);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  //
+  // Map the MMIO window that provides I/O access - the PCI host bridge code
+  // is not aware of this translation and so it will only map the I/O view
+  // in the GCD I/O map.
+  //
+  Status = MapGcdMmioSpace (IoTranslation, *IoSize);
+  ASSERT_EFI_ERROR (Status);
+
+  return Status;
 }
 
 STATIC PCI_ROOT_BRIDGE mRootBridge;
-- 
2.19.1