xlat: Remove mmap_attr_t enum type
The values defined in this type are used in logical operations, which
goes against MISRA Rule 10.1: "Operands shall not be of an inappropriate
essential type".
Now, `unsigned int` is used instead. This also allows us to move the
dynamic mapping bit from 30 to 31. It was an undefined behaviour in the
past because an enum is signed by default, and bit 31 corresponds to the
sign bit. It is undefined behaviour to modify the sign bit. Now, bit 31
is free to use as it was originally meant to be.
mmap_attr_t is now defined as an `unsigned int` for backwards
compatibility.
Change-Id: I6b31218c14b9c7fdabebe432de7fae6e90a97f34
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/include/lib/xlat_tables/xlat_tables.h b/include/lib/xlat_tables/xlat_tables.h
index 91f2f05..c017e19 100644
--- a/include/lib/xlat_tables/xlat_tables.h
+++ b/include/lib/xlat_tables/xlat_tables.h
@@ -25,7 +25,7 @@
#define MAP_REGION(pa, va, sz, attr) {(pa), (va), (sz), (attr)}
/*
- * Shifts and masks to access fields of an mmap_attr_t
+ * Shifts and masks to access fields of an mmap attribute
*/
#define MT_TYPE_MASK U(0x7)
#define MT_TYPE(_attr) ((_attr) & MT_TYPE_MASK)
@@ -39,37 +39,41 @@
/*
* Memory mapping attributes
*/
-typedef enum {
- /*
- * Memory types supported.
- * These are organised so that, going down the list, the memory types
- * are getting weaker; conversely going up the list the memory types are
- * getting stronger.
- */
- MT_DEVICE,
- MT_NON_CACHEABLE,
- MT_MEMORY,
- /* Values up to 7 are reserved to add new memory types in the future */
- MT_RO = U(0) << MT_PERM_SHIFT,
- MT_RW = U(1) << MT_PERM_SHIFT,
+/*
+ * Memory types supported.
+ * These are organised so that, going down the list, the memory types are
+ * getting weaker; conversely going up the list the memory types are getting
+ * stronger.
+ */
+#define MT_DEVICE U(0)
+#define MT_NON_CACHEABLE U(1)
+#define MT_MEMORY U(2)
+/* Values up to 7 are reserved to add new memory types in the future */
- MT_SECURE = U(0) << MT_SEC_SHIFT,
- MT_NS = U(1) << MT_SEC_SHIFT,
+#define MT_RO (U(0) << MT_PERM_SHIFT)
+#define MT_RW (U(1) << MT_PERM_SHIFT)
- /*
- * Access permissions for instruction execution are only relevant for
- * normal read-only memory, i.e. MT_MEMORY | MT_RO. They are ignored
- * (and potentially overridden) otherwise:
- * - Device memory is always marked as execute-never.
- * - Read-write normal memory is always marked as execute-never.
- */
- MT_EXECUTE = U(0) << MT_EXECUTE_SHIFT,
- MT_EXECUTE_NEVER = U(1) << MT_EXECUTE_SHIFT,
-} mmap_attr_t;
+#define MT_SECURE (U(0) << MT_SEC_SHIFT)
+#define MT_NS (U(1) << MT_SEC_SHIFT)
-#define MT_CODE (MT_MEMORY | MT_RO | MT_EXECUTE)
-#define MT_RO_DATA (MT_MEMORY | MT_RO | MT_EXECUTE_NEVER)
+/*
+ * Access permissions for instruction execution are only relevant for normal
+ * read-only memory, i.e. MT_MEMORY | MT_RO. They are ignored (and potentially
+ * overridden) otherwise:
+ * - Device memory is always marked as execute-never.
+ * - Read-write normal memory is always marked as execute-never.
+ */
+#define MT_EXECUTE (U(0) << MT_EXECUTE_SHIFT)
+#define MT_EXECUTE_NEVER (U(1) << MT_EXECUTE_SHIFT)
+
+/* Compound attributes for most common usages */
+#define MT_CODE (MT_MEMORY | MT_RO | MT_EXECUTE)
+#define MT_RO_DATA (MT_MEMORY | MT_RO | MT_EXECUTE_NEVER)
+
+#if !ERROR_DEPRECATED
+typedef unsigned int mmap_attr_t;
+#endif
/*
* Structure for specifying a single region of memory.
@@ -78,13 +82,13 @@
unsigned long long base_pa;
uintptr_t base_va;
size_t size;
- mmap_attr_t attr;
+ unsigned int attr;
} mmap_region_t;
/* Generic translation table APIs */
void init_xlat_tables(void);
void mmap_add_region(unsigned long long base_pa, uintptr_t base_va,
- size_t size, mmap_attr_t attr);
+ size_t size, unsigned int attr);
void mmap_add(const mmap_region_t *mm);
#endif /*__ASSEMBLY__*/