ArmPlatformPkg/NorFlashDxe: initialize varstore headers eagerly

The lazy initialization of the varstore FVB makes no longer sense at this
point:

- "mNorFlashInstanceTemplate.Initialize" is NULL;

- in NorFlashCreateInstance(), we only set Instance->Initialize to
  non-NULL -- namely NorFlashFvbInitialize() -- if the FVB stands for the
  variable store (see "ContainVariableStorage" / "SupportFvb");

- we call Instance->Initialize() from three places:

  - from NorFlashWriteSingleBlock(), which is too late for the variable
    read service ("variable write" depends on "variable read");

  - from InitializeFvAndVariableStoreHeaders(), but that is only reachable
    from NorFlashFvbInitialize(), i.e. recursively from
    Instance->Initialize() itself;

  - and from FvbRead(), which is never called by the variable driver, only
    by the FTW driver. However, the variable driver may read (not write)
    the memory-mapped varstore flash chip before the FTW driver is
    dispatched.

Therefore the lazy initialization is both superfluous and insufficient.
Initialize the varstore headers eagerly, before we install the FVB
protocol interface.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Supreeth Venkatesh <Supreeth.Venkatesh@arm.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Steve Capper <steve.capper@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>

ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c

@@ -32,9 +32,6 @@ NOR_FLASH_INSTANCE  mNorFlashInstanceTemplate = {
   NOR_FLASH_SIGNATURE, // Signature
   NULL, // Handle ... NEED TO BE FILLED
 
-  FALSE, // Initialized
-  NULL, // Initialize
-
   0, // DeviceBaseAddress ... NEED TO BE FILLED
   0, // RegionBaseAddress ... NEED TO BE FILLED
   0, // Size ... NEED TO BE FILLED
@@ -69,7 +66,6 @@ NOR_FLASH_INSTANCE  mNorFlashInstanceTemplate = {
     NorFlashDiskIoWriteDisk        // WriteDisk
   },
 
-  FALSE, // SupportFvb ... NEED TO BE FILLED
   {
     FvbGetAttributes, // GetAttributes
     FvbSetAttributes, // SetAttributes
@@ -137,8 +133,7 @@ NorFlashCreateInstance (
   }
 
   if (SupportFvb) {
-    Instance->SupportFvb = TRUE;
-    Instance->Initialize = NorFlashFvbInitialize;
+    NorFlashFvbInitialize (Instance);
 
     Status = gBS->InstallMultipleProtocolInterfaces (
                   &Instance->Handle,
@@ -152,8 +147,6 @@ NorFlashCreateInstance (
       return Status;
     }
   } else {
-    Instance->Initialized = TRUE;
-
     Status = gBS->InstallMultipleProtocolInterfaces (
                     &Instance->Handle,
                     &gEfiDevicePathProtocolGuid, &Instance->DevicePath,
@@ -924,10 +917,6 @@ NorFlashWriteSingleBlock (
 
   PrevBlockAddress = 0;
 
-  if (!Instance->Initialized && Instance->Initialize) {
-    Instance->Initialize(Instance);
-  }
-
   DEBUG ((DEBUG_BLKIO, "NorFlashWriteSingleBlock(Parameters: Lba=%ld, Offset=0x%x, *NumBytes=0x%x, Buffer @ 0x%08x)\n", Lba, Offset, *NumBytes, Buffer));
 
   // Detect WriteDisabled state

ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.h

@@ -122,8 +122,6 @@
 
 typedef struct _NOR_FLASH_INSTANCE                NOR_FLASH_INSTANCE;
 
-typedef EFI_STATUS (*NOR_FLASH_INITIALIZE)        (NOR_FLASH_INSTANCE* Instance);
-
 typedef struct {
   VENDOR_DEVICE_PATH                  Vendor;
   EFI_DEVICE_PATH_PROTOCOL            End;
@@ -133,9 +131,6 @@ struct _NOR_FLASH_INSTANCE {
   UINT32                              Signature;
   EFI_HANDLE                          Handle;
 
-  BOOLEAN                             Initialized;
-  NOR_FLASH_INITIALIZE                Initialize;
-
   UINTN                               DeviceBaseAddress;
   UINTN                               RegionBaseAddress;
   UINTN                               Size;
@@ -145,7 +140,6 @@ struct _NOR_FLASH_INSTANCE {
   EFI_BLOCK_IO_MEDIA                  Media;
   EFI_DISK_IO_PROTOCOL                DiskIoProtocol;
 
-  BOOLEAN                             SupportFvb;
   EFI_FIRMWARE_VOLUME_BLOCK2_PROTOCOL FvbProtocol;
   VOID*                               ShadowBuffer;
 

ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashFvbDxe.c

@@ -59,10 +59,6 @@ InitializeFvAndVariableStoreHeaders (
   EFI_FIRMWARE_VOLUME_HEADER          *FirmwareVolumeHeader;
   VARIABLE_STORE_HEADER               *VariableStoreHeader;
 
-  if (!Instance->Initialized && Instance->Initialize) {
-    Instance->Initialize (Instance);
-  }
-
   HeadersLength = sizeof(EFI_FIRMWARE_VOLUME_HEADER) + sizeof(EFI_FV_BLOCK_MAP_ENTRY) + sizeof(VARIABLE_STORE_HEADER);
   Headers = AllocateZeroPool(HeadersLength);
 
@@ -431,10 +427,6 @@ FvbRead (
 
   DEBUG ((DEBUG_BLKIO, "FvbRead(Parameters: Lba=%ld, Offset=0x%x, *NumBytes=0x%x, Buffer @ 0x%08x)\n", Instance->StartLba + Lba, Offset, *NumBytes, Buffer));
 
-  if (!Instance->Initialized && Instance->Initialize) {
-    Instance->Initialize(Instance);
-  }
-
   TempStatus = EFI_SUCCESS;
 
   // Cache the block size to avoid de-referencing pointers all the time
@@ -749,7 +741,6 @@ NorFlashFvbInitialize (
       EFI_MEMORY_UC | EFI_MEMORY_RUNTIME);
   ASSERT_EFI_ERROR (Status);
 
-  Instance->Initialized = TRUE;
   mFlashNvStorageVariableBase = FixedPcdGet32 (PcdFlashNvStorageVariableBase);
 
   // Set the index of the first LBA for the FVB