ArmPlatformPkg/NorFlashDxe: use strictly aligned CopyMem()

[mirror_edk2.git] / ArmPlatformPkg / Drivers / NorFlashDxe / NorFlashDxe.c

diff --git a/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c b/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c
index 3abbe5cb32bc2c7f44af3f014e6cb4515e022ff6..ca61ac5e1983d3cdad2e2f1ae59c3b1d6abe814f 100644 (file)
--- a/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c
+++ b/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c
@@ -744,6 +744,65 @@ NorFlashWriteBlocks (
   return Status;\r
 }\r
 \r
+#define BOTH_ALIGNED(a, b, align) ((((UINTN)(a) | (UINTN)(b)) & ((align) - 1)) == 0)\r
+\r
+/**\r
+  Copy Length bytes from Source to Destination, using aligned accesses only.\r
+  Note that this implementation uses memcpy() semantics rather then memmove()\r
+  semantics, i.e., SourceBuffer and DestinationBuffer should not overlap.\r
+\r
+  @param  DestinationBuffer The target of the copy request.\r
+  @param  SourceBuffer      The place to copy from.\r
+  @param  Length            The number of bytes to copy.\r
+\r
+  @return Destination\r
+\r
+**/\r
+STATIC\r
+VOID *\r
+AlignedCopyMem (\r
+  OUT     VOID                      *DestinationBuffer,\r
+  IN      CONST VOID                *SourceBuffer,\r
+  IN      UINTN                     Length\r
+  )\r
+{\r
+  UINT8             *Destination8;\r
+  CONST UINT8       *Source8;\r
+  UINT32            *Destination32;\r
+  CONST UINT32      *Source32;\r
+  UINT64            *Destination64;\r
+  CONST UINT64      *Source64;\r
+\r
+  if (BOTH_ALIGNED(DestinationBuffer, SourceBuffer, 8) && Length >= 8) {\r
+    Destination64 = DestinationBuffer;\r
+    Source64 = SourceBuffer;\r
+    while (Length >= 8) {\r
+      *Destination64++ = *Source64++;\r
+      Length -= 8;\r
+    }\r
+\r
+    Destination8 = (UINT8 *)Destination64;\r
+    Source8 = (CONST UINT8 *)Source64;\r
+  } else if (BOTH_ALIGNED(DestinationBuffer, SourceBuffer, 4) && Length >= 4) {\r
+    Destination32 = DestinationBuffer;\r
+    Source32 = SourceBuffer;\r
+    while (Length >= 4) {\r
+      *Destination32++ = *Source32++;\r
+      Length -= 4;\r
+    }\r
+\r
+    Destination8 = (UINT8 *)Destination32;\r
+    Source8 = (CONST UINT8 *)Source32;\r
+  } else {\r
+    Destination8 = DestinationBuffer;\r
+    Source8 = SourceBuffer;\r
+  }\r
+  while (Length-- != 0) {\r
+    *Destination8++ = *Source8++;\r
+  }\r
+  return DestinationBuffer;\r
+}\r
+\r
 EFI_STATUS\r
 NorFlashReadBlocks (\r
   IN NOR_FLASH_INSTANCE   *Instance,\r
@@ -791,7 +850,7 @@ NorFlashReadBlocks (
   SEND_NOR_COMMAND (Instance->DeviceBaseAddress, 0, P30_CMD_READ_ARRAY);\r
 \r
   // Readout the data\r
-  CopyMem(Buffer, (UINTN *)StartAddress, BufferSizeInBytes);\r
+  AlignedCopyMem (Buffer, (VOID *)StartAddress, BufferSizeInBytes);\r
 \r
   return EFI_SUCCESS;\r
 }\r
@@ -832,7 +891,7 @@ NorFlashRead (
   SEND_NOR_COMMAND (Instance->DeviceBaseAddress, 0, P30_CMD_READ_ARRAY);\r
 \r
   // Readout the data\r
-  CopyMem (Buffer, (UINTN *)(StartAddress + Offset), BufferSizeInBytes);\r
+  AlignedCopyMem (Buffer, (VOID *)StartAddress + Offset, BufferSizeInBytes);\r
 \r
   return EFI_SUCCESS;\r
 }\r