fix(bl2): make BL2 SRAM footprint flexible
On FVP's the default SRAM size is severly restrictive. However, more
recent models support larger SRAM configurations (> 256 Kb). We
introduced the flag FVP_TRUSTED_SRAM_SIZE to allow for TF to handle
different configurations.
BL31 automatically benefits from this optimisation since it starts from
the bottom of shared memory, and runs up to the end of SRAM. Increase
the size of all BL2 builds in proportion to FVP_TRUSTED_SRAM_SIZE so
that BL2 covers around a third of SRAM.
Change-Id: Idf37e8cb86507ea44b97ac8b3b90fffefe13f57a
Signed-off-by: Harrison Mutai <harrison.mutai@arm.com>
diff --git a/plat/arm/board/fvp/include/platform_def.h b/plat/arm/board/fvp/include/platform_def.h
index 193052d..4b69d66 100644
--- a/plat/arm/board/fvp/include/platform_def.h
+++ b/plat/arm/board/fvp/include/platform_def.h
@@ -234,7 +234,13 @@
/* When ARM_BL31_IN_DRAM is set, BL2 can use almost all of Trusted SRAM. */
# define PLAT_ARM_MAX_BL2_SIZE (UL(0x1F000) - FVP_BL2_ROMLIB_OPTIMIZATION)
#else
-# define PLAT_ARM_MAX_BL2_SIZE (UL(0x13000) - FVP_BL2_ROMLIB_OPTIMIZATION)
+/**
+ * Default to just under half of SRAM to ensure there's enough room for really
+ * large BL31 build configurations when using the default SRAM size (256 Kb).
+ */
+#define PLAT_ARM_MAX_BL2_SIZE \
+ (((PLAT_ARM_TRUSTED_SRAM_SIZE / 3) & ~PAGE_SIZE_MASK) - PAGE_SIZE - \
+ FVP_BL2_ROMLIB_OPTIMIZATION)
#endif
#if RESET_TO_BL31