ARM platforms: Move BL31 below BL2 to enable BL2 overlay
The patch changes the layout of BL images in memory to enable
more efficient use of available space. Previously BL31 was loaded
with the expectation that BL2 memory would be reclaimed by BL32
loaded in SRAM. But with increasing memory requirements in the
firmware, we can no longer fit BL32 in SRAM anymore which means the
BL2 memory is not reclaimed by any runtime image. Positioning BL2
below BL1-RW and above BL31 means that the BL31 NOBITS can be
overlaid on BL2 and BL1-RW.
This patch also propogates the same memory layout to BL32 for AArch32
mode. The reset addresses for the following configurations are also
changed :
* When RESET_TO_SP_MIN=1 for BL32 in AArch32 mode
* When BL2_AT_EL3=1 for BL2
The restriction on BL31 to be only in DRAM when SPM is enabled
is now removed with this change. The update to the firmware design
guide for the BL memory layout is done in the following patch.
Change-Id: Icca438e257abe3e4f5a8215f945b9c3f9fbf29c9
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
diff --git a/plat/arm/common/arm_bl2_setup.c b/plat/arm/common/arm_bl2_setup.c
index d490f83..4ef3a9b 100644
--- a/plat/arm/common/arm_bl2_setup.c
+++ b/plat/arm/common/arm_bl2_setup.c
@@ -25,18 +25,10 @@
static meminfo_t bl2_tzram_layout __aligned(CACHE_WRITEBACK_GRANULE);
/*
- * Check that BL2_BASE is atleast a page over ARM_BL_RAM_BASE. The page is for
- * `meminfo_t` data structure and TB_FW_CONFIG passed from BL1. Not needed
- * when BL2 is compiled for BL_AT_EL3 as BL2 doesn't need any info from BL1 and
- * BL2 is loaded at base of usable SRAM.
+ * Check that BL2_BASE is above ARM_TB_FW_CONFIG_LIMIT. This reserved page is
+ * for `meminfo_t` data structure and fw_configs passed from BL1.
*/
-#if BL2_AT_EL3
-#define BL1_MEMINFO_OFFSET 0x0
-#else
-#define BL1_MEMINFO_OFFSET PAGE_SIZE
-#endif
-
-CASSERT(BL2_BASE >= (ARM_BL_RAM_BASE + BL1_MEMINFO_OFFSET), assert_bl2_base_overflows);
+CASSERT(BL2_BASE >= ARM_TB_FW_CONFIG_LIMIT, assert_bl2_base_overflows);
/* Weak definitions may be overridden in specific ARM standard platform */
#pragma weak bl2_early_platform_setup2