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/include/plat/arm/css/common/css_def.h b/include/plat/arm/css/common/css_def.h
index 6d68b44..725c27c 100644
--- a/include/plat/arm/css/common/css_def.h
+++ b/include/plat/arm/css/common/css_def.h
@@ -158,14 +158,14 @@
/*
* Load address of SCP_BL2 in CSS platform ports
* SCP_BL2 is loaded to the same place as BL31 but it shouldn't overwrite BL1
- * rw data. Once SCP_BL2 is transferred to the SCP, it is discarded and BL31
- * is loaded over the top.
+ * rw data or BL2. Once SCP_BL2 is transferred to the SCP, it is discarded and
+ * BL31 is loaded over the top.
*/
-#define SCP_BL2_BASE (BL1_RW_BASE - PLAT_CSS_MAX_SCP_BL2_SIZE)
-#define SCP_BL2_LIMIT BL1_RW_BASE
+#define SCP_BL2_BASE (BL2_BASE - PLAT_CSS_MAX_SCP_BL2_SIZE)
+#define SCP_BL2_LIMIT BL2_BASE
-#define SCP_BL2U_BASE (BL1_RW_BASE - PLAT_CSS_MAX_SCP_BL2U_SIZE)
-#define SCP_BL2U_LIMIT BL1_RW_BASE
+#define SCP_BL2U_BASE (BL2_BASE - PLAT_CSS_MAX_SCP_BL2U_SIZE)
+#define SCP_BL2U_LIMIT BL2_BASE
#endif /* CSS_LOAD_SCP_IMAGES */
/* Load address of Non-Secure Image for CSS platform ports */