Rationalise MMU and Page table related constants on ARM platforms

`board_arm_def.h` contains multiple definitions of
`PLAT_ARM_MMAP_ENTRIES` and `MAX_XLAT_TABLES` that are optimised for
memory usage depending upon the chosen build configuration. To ease
maintenance of these constants, this patch replaces their multiple
definitions with a single set of definitions that will work on all ARM
platforms.

Platforms can override the defaults with optimal values by enabling the
`ARM_BOARD_OPTIMISE_MMAP` build option. An example has been provided in
the Juno ADP port.

Additionally, `PLAT_ARM_MMAP_ENTRIES` is increased by one to accomodate
future ARM platforms.

Change-Id: I5ba6490fdd1e118cc9cc2d988ad7e9c38492b6f0

1 files changed, 18 insertions, 70 deletions

diff --git a/include/plat/arm/board/common/board_arm_def.h b/include/plat/arm/board/common/board_arm_def.h
index db2a8dfb..aaf419e2 100644
--- a/include/plat/arm/board/common/board_arm_def.h
+++ b/include/plat/arm/board/common/board_arm_def.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -60,80 +60,28 @@
 #endif
 
 /*
- * PLAT_ARM_MMAP_ENTRIES depends on the number of entries in the
- * plat_arm_mmap array defined for each BL stage.
+ * The constants below are not optimised for memory usage. Platforms that wish
+ * to optimise these constants should set `ARM_BOARD_OPTIMISE_MMAP` to 1 and
+ * provide there own values.
  */
-#if IMAGE_BL1
-# if PLAT_fvp
-#  if TRUSTED_BOARD_BOOT
-#   define PLAT_ARM_MMAP_ENTRIES	8
-#  else
-#   define PLAT_ARM_MMAP_ENTRIES	7
-#  endif	/* TRUSTED_BOARD_BOOT */
-# else
-#  if TRUSTED_BOARD_BOOT
-#   define PLAT_ARM_MMAP_ENTRIES	7
-#  else
-#   define PLAT_ARM_MMAP_ENTRIES	6
-#  endif	/* TRUSTED_BOARD_BOOT */
-# endif		/* PLAT_ */
-#endif
-#if IMAGE_BL2
-# if PLAT_fvp
-#  define PLAT_ARM_MMAP_ENTRIES		9
-# else
-#  define PLAT_ARM_MMAP_ENTRIES		8
-# endif
-#endif
-#if IMAGE_BL2U
-# if PLAT_fvp
-#  define PLAT_ARM_MMAP_ENTRIES		3
-# else
-#  define PLAT_ARM_MMAP_ENTRIES		4
-#endif
-#endif
-#if IMAGE_BL31
-#define PLAT_ARM_MMAP_ENTRIES		5
-#endif
-#if IMAGE_BL32
-#define PLAT_ARM_MMAP_ENTRIES		4
-#endif
-
+#if !ARM_BOARD_OPTIMISE_MMAP
 /*
- * Platform specific page table and MMU setup constants
+ * PLAT_ARM_MMAP_ENTRIES depends on the number of entries in the
+ * plat_arm_mmap array defined for each BL stage.
+ *
+ * Provide relatively optimised values for the runtime images (BL31 and BL32).
+ * Optimisation is less important for the other, transient boot images so a
+ * common, maximum value is used across these images.
  */
-#if IMAGE_BL1
-# if TRUSTED_BOARD_BOOT
-#  define MAX_XLAT_TABLES		4
-# else
-#  if PLAT_juno
-#   define MAX_XLAT_TABLES		2
-#  else
-#   define MAX_XLAT_TABLES		3
-#  endif /* PLAT_ */
-# endif	/* TRUSTED_BOARD_BOOT */
-#elif IMAGE_BL2
-# if PLAT_juno
-#  define MAX_XLAT_TABLES		3
-# else
-#  define MAX_XLAT_TABLES		4
-# endif /* PLAT_ */
-#elif IMAGE_BL2U
-# if PLAT_juno
-#  define MAX_XLAT_TABLES		3
-# else
-#  define MAX_XLAT_TABLES		4
-# endif /* PLAT_ */
-#elif IMAGE_BL31
-# define MAX_XLAT_TABLES		2
-#elif IMAGE_BL32
-# if ARM_TSP_RAM_LOCATION_ID == ARM_DRAM_ID
-#  define MAX_XLAT_TABLES		3
-# else
-#  define MAX_XLAT_TABLES		2
-# endif
+#if IMAGE_BL31 || IMAGE_BL32
+# define PLAT_ARM_MMAP_ENTRIES		6
+# define MAX_XLAT_TABLES		3
+#else
+# define PLAT_ARM_MMAP_ENTRIES		9
+# define MAX_XLAT_TABLES		4
 #endif
 
+#endif /* ARM_BOARD_OPTIMISE_MMAP */
 
 #define MAX_IO_DEVICES			3
 #define MAX_IO_HANDLES			4