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/css/drivers/scp/css_bom_bootloader.c b/plat/arm/css/drivers/scp/css_bom_bootloader.c
index 42ed30d..5268510 100644
--- a/plat/arm/css/drivers/scp/css_bom_bootloader.c
+++ b/plat/arm/css/drivers/scp/css_bom_bootloader.c
@@ -47,16 +47,16 @@
} cmd_data_payload_t;
/*
- * All CSS platforms load SCP_BL2/SCP_BL2U just below BL rw-data and above
- * BL2/BL2U (this is where BL31 usually resides except when ARM_BL31_IN_DRAM is
- * set. Ensure that SCP_BL2/SCP_BL2U do not overflow into BL1 rw-data nor
- * BL2/BL2U.
+ * All CSS platforms load SCP_BL2/SCP_BL2U just below BL2 (this is where BL31
+ * usually resides except when ARM_BL31_IN_DRAM is
+ * set). Ensure that SCP_BL2/SCP_BL2U do not overflow into shared RAM and
+ * the tb_fw_config.
*/
-CASSERT(SCP_BL2_LIMIT <= BL1_RW_BASE, assert_scp_bl2_overwrite_bl1);
-CASSERT(SCP_BL2U_LIMIT <= BL1_RW_BASE, assert_scp_bl2u_overwrite_bl1);
+CASSERT(SCP_BL2_LIMIT <= BL2_BASE, assert_scp_bl2_overwrite_bl2);
+CASSERT(SCP_BL2U_LIMIT <= BL2_BASE, assert_scp_bl2u_overwrite_bl2);
-CASSERT(SCP_BL2_BASE >= BL2_LIMIT, assert_scp_bl2_overwrite_bl2);
-CASSERT(SCP_BL2U_BASE >= BL2U_LIMIT, assert_scp_bl2u_overwrite_bl2u);
+CASSERT(SCP_BL2_BASE >= ARM_TB_FW_CONFIG_LIMIT, assert_scp_bl2_overflow);
+CASSERT(SCP_BL2U_BASE >= ARM_TB_FW_CONFIG_LIMIT, assert_scp_bl2u_overflow);
static void scp_boot_message_start(void)
{
diff --git a/plat/arm/css/drivers/scp/css_scp.h b/plat/arm/css/drivers/scp/css_scp.h
index 1f0cf8e..671612a 100644
--- a/plat/arm/css/drivers/scp/css_scp.h
+++ b/plat/arm/css/drivers/scp/css_scp.h
@@ -34,17 +34,17 @@
int css_scp_boot_ready(void);
#if CSS_LOAD_SCP_IMAGES
-/*
- * All CSS platforms load SCP_BL2/SCP_BL2U just below BL rw-data and above
- * BL2/BL2U (this is where BL31 usually resides except when ARM_BL31_IN_DRAM is
- * set. Ensure that SCP_BL2/SCP_BL2U do not overflow into BL1 rw-data nor
- * BL2/BL2U.
- */
-CASSERT(SCP_BL2_LIMIT <= BL1_RW_BASE, assert_scp_bl2_limit_overwrite_bl1);
-CASSERT(SCP_BL2U_LIMIT <= BL1_RW_BASE, assert_scp_bl2u_limit_overwrite_bl1);
-CASSERT(SCP_BL2_BASE >= BL2_LIMIT, assert_scp_bl2_overwrite_bl2);
-CASSERT(SCP_BL2U_BASE >= BL2U_LIMIT, assert_scp_bl2u_overwrite_bl2u);
+/*
+ * All CSS platforms load SCP_BL2/SCP_BL2U just below BL2 (this is where BL31
+ * usually resides except when ARM_BL31_IN_DRAM is
+ * set). Ensure that SCP_BL2/SCP_BL2U do not overflow into tb_fw_config.
+ */
+CASSERT(SCP_BL2_LIMIT <= BL2_BASE, assert_scp_bl2_overwrite_bl2);
+CASSERT(SCP_BL2U_LIMIT <= BL2_BASE, assert_scp_bl2u_overwrite_bl2);
+
+CASSERT(SCP_BL2_BASE >= ARM_TB_FW_CONFIG_LIMIT, assert_scp_bl2_overflow);
+CASSERT(SCP_BL2U_BASE >= ARM_TB_FW_CONFIG_LIMIT, assert_scp_bl2u_overflow);
#endif
#endif /* __CSS_SCP_H__ */