Hardware: Fix a regression caused by bit width mask generation

A regression was reported to the shift offset >= width of type.
This patch fixes this issue. BZ 1270. Lv Zheng.

Link: https://bugs.acpica.org/show_bug.cgi?id=1270
Reported-by: Sascha Wildner <[email protected]>
Signed-off-by: Lv Zheng <[email protected]>

Author: Lv Zheng

source/components/executer/exfldio.c

@@ -1018,20 +1018,9 @@ AcpiExInsertIntoField (
 
     AccessBitWidth = ACPI_MUL_8 (ObjDesc->CommonField.AccessByteWidth);
 
-    /*
-     * Create the bitmasks used for bit insertion.
-     * Note: This if/else is used to bypass compiler differences with the
-     * shift operator
-     */
-    if (AccessBitWidth == ACPI_INTEGER_BIT_SIZE)
-    {
-        WidthMask = ACPI_UINT64_MAX;
-    }
-    else
-    {
-        WidthMask = ACPI_MASK_BITS_ABOVE (AccessBitWidth);
-    }
+    /* Create the bitmasks used for bit insertion */
 
+    WidthMask = ACPI_MASK_BITS_ABOVE_64 (AccessBitWidth);
     Mask = WidthMask &
         ACPI_MASK_BITS_BELOW (ObjDesc->CommonField.StartFieldBitOffset);
 

source/components/hardware/hwregs.c

@@ -315,7 +315,7 @@ AcpiHwRead (
         }
 
         ACPI_SET_BITS (Value, Index * AccessWidth,
-            (1 << AccessWidth) - 1, Value32);
+            ACPI_MASK_BITS_ABOVE_32 (AccessWidth), Value32);
 
         BitWidth -= BitWidth > AccessWidth ? AccessWidth : BitWidth;
         Index++;
@@ -386,7 +386,7 @@ AcpiHwWrite (
     while (BitWidth)
     {
         NewValue32 = ACPI_GET_BITS (&Value, Index * AccessWidth,
-            (1 << AccessWidth) - 1);
+            ACPI_MASK_BITS_ABOVE_32 (AccessWidth));
 
         if (BitOffset > AccessWidth)
         {

source/include/acmacros.h

@@ -345,9 +345,21 @@
  * Bit positions start at zero.
  * MASK_BITS_ABOVE creates a mask starting AT the position and above
  * MASK_BITS_BELOW creates a mask starting one bit BELOW the position
+ * MASK_BITS_ABOVE/BELOW accpets a bit offset to create a mask
+ * MASK_BITS_ABOVE/BELOW_32/64 accpets a bit width to create a mask
+ * Note: The ACPI_INTEGER_BIT_SIZE check is used to bypass compiler
+ * differences with the shift operator
  */
 #define ACPI_MASK_BITS_ABOVE(position)      (~((ACPI_UINT64_MAX) << ((UINT32) (position))))
 #define ACPI_MASK_BITS_BELOW(position)      ((ACPI_UINT64_MAX) << ((UINT32) (position)))
+#define ACPI_MASK_BITS_ABOVE_32(width)      ((UINT32) ACPI_MASK_BITS_ABOVE(width))
+#define ACPI_MASK_BITS_BELOW_32(width)      ((UINT32) ACPI_MASK_BITS_BELOW(width))
+#define ACPI_MASK_BITS_ABOVE_64(width)      ((width) == ACPI_INTEGER_BIT_SIZE ? \
+                                                ACPI_UINT64_MAX : \
+                                                ACPI_MASK_BITS_ABOVE(width))
+#define ACPI_MASK_BITS_BELOW_64(width)      ((width) == ACPI_INTEGER_BIT_SIZE ? \
+                                                (UINT64) 0 : \
+                                                ACPI_MASK_BITS_BELOW(width))
 
 /* Bitfields within ACPI registers */