Merge pull request #1404 from soby-mathew/sm/bl_layout_change

ARM platforms: Change memory layout and update documentation

13 files changed, 146 insertions, 153 deletions

diff --git a/docs/firmware-design.rst b/docs/firmware-design.rst
index 477eeaa54..51f5b42eb 100644
--- a/docs/firmware-design.rst
+++ b/docs/firmware-design.rst
@@ -516,8 +516,8 @@ This functionality can be tested with FVP loading the image directly
 in memory and changing the address where the system jumps at reset.
 For example:
 
-	-C cluster0.cpu0.RVBAR=0x4014000
-	--data cluster0.cpu0=bl2.bin@0x4014000
+	-C cluster0.cpu0.RVBAR=0x4020000
+	--data cluster0.cpu0=bl2.bin@0x4020000
 
 With this configuration, FVP is like a platform of the first case,
 where the Boot ROM jumps always to the same address. For simplification,
@@ -1743,17 +1743,20 @@ The following list describes the memory layout on the Arm development platforms:
    this is also used for the MHU payload when passing messages to and from the
    SCP.
 
+-  Another 4 KB page is reserved for passing memory layout between BL1 and BL2
+   and also the dynamic firmware configurations.
+
 -  On FVP, BL1 is originally sitting in the Trusted ROM at address ``0x0``. On
    Juno, BL1 resides in flash memory at address ``0x0BEC0000``. BL1 read-write
    data are relocated to the top of Trusted SRAM at runtime.
 
+-  BL2 is loaded below BL1 RW
+
 -  EL3 Runtime Software, BL31 for AArch64 and BL32 for AArch32 (e.g. SP\_MIN),
    is loaded at the top of the Trusted SRAM, such that its NOBITS sections will
-   overwrite BL1 R/W data. This implies that BL1 global variables remain valid
-   only until execution reaches the EL3 Runtime Software entry point during a
-   cold boot.
-
--  BL2 is loaded below EL3 Runtime Software.
+   overwrite BL1 R/W data and BL2. This implies that BL1 global variables
+   remain valid only until execution reaches the EL3 Runtime Software entry
+   point during a cold boot.
 
 -  On Juno, SCP\_BL2 is loaded temporarily into the EL3 Runtime Software memory
    region and transfered to the SCP before being overwritten by EL3 Runtime
@@ -1766,9 +1769,8 @@ The following list describes the memory layout on the Arm development platforms:
    -  Secure region of DRAM (top 16MB of DRAM configured by the TrustZone
       controller)
 
-   When BL32 (for AArch64) is loaded into Trusted SRAM, its NOBITS sections
-   are allowed to overlay BL2. This memory layout is designed to give the
-   BL32 image as much memory as possible when it is loaded into Trusted SRAM.
+   When BL32 (for AArch64) is loaded into Trusted SRAM, it is loaded below
+   BL31.
 
 When LOAD\_IMAGE\_V2 is disabled the memory regions for the overlap detection
 mechanism at boot time are defined as follows (shown per API):
@@ -1814,21 +1816,32 @@ an example.
 Note: Loading the BL32 image in TZC secured DRAM doesn't change the memory
 layout of the other images in Trusted SRAM.
 
-**FVP with TSP in Trusted SRAM (default option):**
+**FVP with TSP in Trusted SRAM with firmware configs :**
 (These diagrams only cover the AArch64 case)
 
 ::
 
+                   DRAM
+    0xffffffff +----------+
+               :          :
+               |----------|
+               |HW_CONFIG |
+    0x83000000 |----------|  (non-secure)
+               |          |
+    0x80000000 +----------+
+
                Trusted SRAM
-    0x04040000 +----------+  loaded by BL2  ------------------
-               | BL1 (rw) |  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+    0x04040000 +----------+  loaded by BL2  +----------------+
+               | BL1 (rw) |  <<<<<<<<<<<<<  |                |
+               |----------|  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+               |   BL2    |  <<<<<<<<<<<<<  |                |
                |----------|  <<<<<<<<<<<<<  |----------------|
                |          |  <<<<<<<<<<<<<  | BL31 PROGBITS  |
-               |----------|                 ------------------
-               |   BL2    |  <<<<<<<<<<<<<  |  BL32 NOBITS   |
-               |----------|  <<<<<<<<<<<<<  |----------------|
-               |          |  <<<<<<<<<<<<<  | BL32 PROGBITS  |
-    0x04001000 +----------+                 ------------------
+               |          |  <<<<<<<<<<<<<  |----------------|
+               |          |  <<<<<<<<<<<<<  |     BL32       |
+    0x04002000 +----------+                 +----------------+
+               |fw_configs|
+    0x04001000 +----------+
                |  Shared  |
     0x04000000 +----------+
 
@@ -1837,7 +1850,7 @@ layout of the other images in Trusted SRAM.
                | BL1 (ro) |
     0x00000000 +----------+
 
-**FVP with TSP in Trusted DRAM with TB_FW_CONFIG and HW_CONFIG :**
+**FVP with TSP in Trusted DRAM with firmware configs (default option):**
 
 ::
 
@@ -1856,17 +1869,15 @@ layout of the other images in Trusted SRAM.
     0x06000000 +--------------+
 
                  Trusted SRAM
-    0x04040000 +--------------+  loaded by BL2  ------------------
-               |   BL1 (rw)   |  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+    0x04040000 +--------------+  loaded by BL2  +----------------+
+               |   BL1 (rw)   |  <<<<<<<<<<<<<  |                |
+               |--------------|  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+               |     BL2      |  <<<<<<<<<<<<<  |                |
                |--------------|  <<<<<<<<<<<<<  |----------------|
                |              |  <<<<<<<<<<<<<  | BL31 PROGBITS  |
-               |--------------|                 ------------------
-               |     BL2      |
-               |--------------|
-               |              |
-               |--------------|
-               | TB_FW_CONFIG |
-               |--------------|
+               |              |                 +----------------+
+               +--------------+
+               |  fw_configs  |
     0x04001000 +--------------+
                |    Shared    |
     0x04000000 +--------------+
@@ -1876,7 +1887,7 @@ layout of the other images in Trusted SRAM.
                |   BL1 (ro)   |
     0x00000000 +--------------+
 
-**FVP with TSP in TZC-Secured DRAM:**
+**FVP with TSP in TZC-Secured DRAM with firmware configs :**
 
 ::
 
@@ -1885,19 +1896,22 @@ layout of the other images in Trusted SRAM.
                |  BL32    |  (secure)
     0xff000000 +----------+
                |          |
-               :          :  (non-secure)
+               |----------|
+               |HW_CONFIG |
+    0x83000000 |----------|  (non-secure)
                |          |
     0x80000000 +----------+
 
                Trusted SRAM
-    0x04040000 +----------+  loaded by BL2  ------------------
-               | BL1 (rw) |  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+    0x04040000 +----------+  loaded by BL2  +----------------+
+               | BL1 (rw) |  <<<<<<<<<<<<<  |                |
+               |----------|  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+               |   BL2    |  <<<<<<<<<<<<<  |                |
                |----------|  <<<<<<<<<<<<<  |----------------|
                |          |  <<<<<<<<<<<<<  | BL31 PROGBITS  |
-               |----------|                 ------------------
-               |   BL2    |
-               |----------|
-               |          |
+               |          |                 +----------------+
+    0x04002000 +----------+
+               |fw_configs|
     0x04001000 +----------+
                |  Shared  |
     0x04000000 +----------+
@@ -1907,7 +1921,7 @@ layout of the other images in Trusted SRAM.
                | BL1 (ro) |
     0x00000000 +----------+
 
-**Juno with BL32 in Trusted SRAM (default option):**
+**Juno with BL32 in Trusted SRAM :**
 
 ::
 
@@ -1921,19 +1935,21 @@ layout of the other images in Trusted SRAM.
     0x08000000 +----------+                  BL31 is loaded
                                              after SCP_BL2 has
                Trusted SRAM                  been sent to SCP
-    0x04040000 +----------+  loaded by BL2  ------------------
-               | BL1 (rw) |  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+    0x04040000 +----------+  loaded by BL2  +----------------+
+               | BL1 (rw) |  <<<<<<<<<<<<<  |                |
+               |----------|  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+               |   BL2    |  <<<<<<<<<<<<<  |                |
                |----------|  <<<<<<<<<<<<<  |----------------|
                | SCP_BL2  |  <<<<<<<<<<<<<  | BL31 PROGBITS  |
-               |----------|                 ------------------
-               |   BL2    |  <<<<<<<<<<<<<  |  BL32 NOBITS   |
                |----------|  <<<<<<<<<<<<<  |----------------|
-               |          |  <<<<<<<<<<<<<  | BL32 PROGBITS  |
-    0x04001000 +----------+                 ------------------
+               |          |  <<<<<<<<<<<<<  |     BL32       |
+               |          |                 +----------------+
+               |          |
+    0x04001000 +----------+
                |   MHU    |
     0x04000000 +----------+
 
-**Juno with BL32 in TZC-secured DRAM:**
+**Juno with BL32 in TZC-secured DRAM :**
 
 ::
 
@@ -1956,14 +1972,13 @@ layout of the other images in Trusted SRAM.
     0x08000000 +----------+                  BL31 is loaded
                                              after SCP_BL2 has
                Trusted SRAM                  been sent to SCP
-    0x04040000 +----------+  loaded by BL2  ------------------
-               | BL1 (rw) |  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+    0x04040000 +----------+  loaded by BL2  +----------------+
+               | BL1 (rw) |  <<<<<<<<<<<<<  |                |
+               |----------|  <<<<<<<<<<<<<  |  BL31 NOBITS   |
+               |   BL2    |  <<<<<<<<<<<<<  |                |
                |----------|  <<<<<<<<<<<<<  |----------------|
                | SCP_BL2  |  <<<<<<<<<<<<<  | BL31 PROGBITS  |
-               |----------|                 ------------------
-               |   BL2    |
-               |----------|
-               |          |
+               |----------|                 +----------------+
     0x04001000 +----------+
                |   MHU    |
     0x04000000 +----------+
diff --git a/docs/user-guide.rst b/docs/user-guide.rst
index 5f3823dbe..f6d0c7641 100644
--- a/docs/user-guide.rst
+++ b/docs/user-guide.rst
@@ -1928,7 +1928,7 @@ with 8 CPUs using the AArch32 build of TF-A.
     -C cluster1.cpu1.RVBAR=0x04001000                            \
     -C cluster1.cpu2.RVBAR=0x04001000                            \
     -C cluster1.cpu3.RVBAR=0x04001000                            \
-    --data cluster0.cpu0="<path-to>/<bl32-binary>"@0x04001000    \
+    --data cluster0.cpu0="<path-to>/<bl32-binary>"@0x04002000    \
     --data cluster0.cpu0="<path-to>/<bl33-binary>"@0x88000000    \
     --data cluster0.cpu0="<path-to>/<fdt>"@0x82000000            \
     --data cluster0.cpu0="<path-to>/<kernel-binary>"@0x80080000  \
@@ -1959,7 +1959,7 @@ boot Linux with 8 CPUs using the AArch64 build of TF-A.
     -C cluster1.cpu2.RVBARADDR=0x04020000                        \
     -C cluster1.cpu3.RVBARADDR=0x04020000                        \
     --data cluster0.cpu0="<path-to>/<bl31-binary>"@0x04020000    \
-    --data cluster0.cpu0="<path-to>/<bl32-binary>"@0x04001000    \
+    --data cluster0.cpu0="<path-to>/<bl32-binary>"@0x04002000    \
     --data cluster0.cpu0="<path-to>/<bl33-binary>"@0x88000000    \
     --data cluster0.cpu0="<path-to>/<fdt>"@0x82000000            \
     --data cluster0.cpu0="<path-to>/<kernel-binary>"@0x80080000  \
@@ -1982,7 +1982,7 @@ boot Linux with 4 CPUs using the AArch32 build of TF-A.
     -C cluster0.cpu1.RVBARADDR=0x04001000                       \
     -C cluster0.cpu2.RVBARADDR=0x04001000                       \
     -C cluster0.cpu3.RVBARADDR=0x04001000                       \
-    --data cluster0.cpu0="<path-to>/<bl32-binary>"@0x04001000   \
+    --data cluster0.cpu0="<path-to>/<bl32-binary>"@0x04002000   \
     --data cluster0.cpu0="<path-to>/<bl33-binary>"@0x88000000   \
     --data cluster0.cpu0="<path-to>/<fdt>"@0x82000000           \
     --data cluster0.cpu0="<path-to>/<kernel-binary>"@0x80080000 \
diff --git a/include/plat/arm/board/common/board_arm_def.h b/include/plat/arm/board/common/board_arm_def.h
index 21ceae30a..2d8e4c139 100644
--- a/include/plat/arm/board/common/board_arm_def.h
+++ b/include/plat/arm/board/common/board_arm_def.h
@@ -93,21 +93,19 @@
 #endif
 
 /*
- * PLAT_ARM_MAX_BL31_SIZE is calculated using the current BL31 debug size plus a
- * little space for growth.
+ * Since BL31 NOBITS overlays BL2 and BL1-RW, PLAT_ARM_MAX_BL31_SIZE is
+ * calculated using the current BL31 PROGBITS debug size plus the sizes of
+ * BL2 and BL1-RW
  */
-#if ENABLE_SPM
-# define PLAT_ARM_MAX_BL31_SIZE		0x40000
-#else
-# define PLAT_ARM_MAX_BL31_SIZE		0x20000
-#endif
+#define PLAT_ARM_MAX_BL31_SIZE		0x3B000
 
 #ifdef AARCH32
 /*
- * PLAT_ARM_MAX_BL32_SIZE is calculated for SP_MIN as the AArch32 Secure
- * Payload.
+ * Since BL32 NOBITS overlays BL2 and BL1-RW, PLAT_ARM_MAX_BL32_SIZE is
+ * calculated using the current SP_MIN PROGBITS debug size plus the sizes of
+ * BL2 and BL1-RW
  */
-# define PLAT_ARM_MAX_BL32_SIZE		0x1D000
+# define PLAT_ARM_MAX_BL32_SIZE		0x3B000
 #endif
 
 #endif /* ARM_BOARD_OPTIMISE_MEM */
diff --git a/include/plat/arm/common/arm_def.h b/include/plat/arm/common/arm_def.h
index 18390d6a7..1f62ebe7d 100644
--- a/include/plat/arm/common/arm_def.h
+++ b/include/plat/arm/common/arm_def.h
@@ -317,7 +317,7 @@
  * and limit. Leave enough space of BL2 meminfo.
  */
 #define ARM_TB_FW_CONFIG_BASE		ARM_BL_RAM_BASE + sizeof(meminfo_t)
-#define ARM_TB_FW_CONFIG_LIMIT		BL2_BASE
+#define ARM_TB_FW_CONFIG_LIMIT		ARM_BL_RAM_BASE + PAGE_SIZE
 
 /*******************************************************************************
  * BL1 specific defines.
@@ -338,32 +338,18 @@
 /*******************************************************************************
  * BL2 specific defines.
  ******************************************************************************/
-#if ARM_BL31_IN_DRAM
-/*
- * For AArch64 BL31 is loaded in the DRAM.
- * Put BL2 just below BL1.
- */
-#define BL2_BASE			(BL1_RW_BASE - PLAT_ARM_MAX_BL2_SIZE)
-#define BL2_LIMIT			BL1_RW_BASE
-
-#elif BL2_AT_EL3
-
-#define BL2_BASE			ARM_BL_RAM_BASE
+#if BL2_AT_EL3
+/* Put BL2 in the middle of the Trusted SRAM */
+#define BL2_BASE			(ARM_TRUSTED_SRAM_BASE + \
+						(PLAT_ARM_TRUSTED_SRAM_SIZE >> 1))
 #define BL2_LIMIT			(ARM_BL_RAM_BASE + ARM_BL_RAM_SIZE)
 
-#elif defined(AARCH32) || JUNO_AARCH32_EL3_RUNTIME
-/*
- * Put BL2 just below BL32.
- */
-#define BL2_BASE			(BL32_BASE - PLAT_ARM_MAX_BL2_SIZE)
-#define BL2_LIMIT			BL32_BASE
-
 #else
 /*
- * Put BL2 just below BL31.
+ * Put BL2 just below BL1.
  */
-#define BL2_BASE			(BL31_BASE - PLAT_ARM_MAX_BL2_SIZE)
-#define BL2_LIMIT			BL31_BASE
+#define BL2_BASE			(BL1_RW_BASE - PLAT_ARM_MAX_BL2_SIZE)
+#define BL2_LIMIT			BL1_RW_BASE
 #endif
 
 /*******************************************************************************
@@ -384,13 +370,10 @@
 						(PLAT_ARM_TRUSTED_SRAM_SIZE >> 1))
 #define BL31_LIMIT			(ARM_BL_RAM_BASE + ARM_BL_RAM_SIZE)
 #else
-/*
- * Put BL31 at the top of the Trusted SRAM.
- */
-#define BL31_BASE			(ARM_BL_RAM_BASE +		\
-						ARM_BL_RAM_SIZE -	\
-						PLAT_ARM_MAX_BL31_SIZE)
-#define BL31_PROGBITS_LIMIT		BL1_RW_BASE
+/* Put BL31 below BL2 in the Trusted SRAM.*/
+#define BL31_BASE			((ARM_BL_RAM_BASE + ARM_BL_RAM_SIZE)\
+						- PLAT_ARM_MAX_BL31_SIZE)
+#define BL31_PROGBITS_LIMIT		BL2_BASE
 #define BL31_LIMIT			(ARM_BL_RAM_BASE + ARM_BL_RAM_SIZE)
 #endif
 
@@ -399,15 +382,17 @@
  * BL32 specific defines for EL3 runtime in AArch32 mode
  ******************************************************************************/
 # if RESET_TO_SP_MIN && !JUNO_AARCH32_EL3_RUNTIME
-/* SP_MIN is the only BL image in SRAM. Allocate the whole of SRAM to BL32 */
-#  define BL32_BASE			ARM_BL_RAM_BASE
+/*
+ * SP_MIN is the only BL image in SRAM. Allocate the whole of SRAM (excluding
+ * the page reserved for fw_configs) to BL32
+ */
+#  define BL32_BASE			ARM_TB_FW_CONFIG_LIMIT
 #  define BL32_LIMIT			(ARM_BL_RAM_BASE + ARM_BL_RAM_SIZE)
 # else
-/* Put BL32 at the top of the Trusted SRAM.*/
-#  define BL32_BASE			(ARM_BL_RAM_BASE +		\
-						ARM_BL_RAM_SIZE -	\
-						PLAT_ARM_MAX_BL32_SIZE)
-#  define BL32_PROGBITS_LIMIT		BL1_RW_BASE
+/* Put BL32 below BL2 in the Trusted SRAM.*/
+#  define BL32_BASE			((ARM_BL_RAM_BASE + ARM_BL_RAM_SIZE)\
+						- PLAT_ARM_MAX_BL32_SIZE)
+#  define BL32_PROGBITS_LIMIT		BL2_BASE
 #  define BL32_LIMIT			(ARM_BL_RAM_BASE + ARM_BL_RAM_SIZE)
 # endif /* RESET_TO_SP_MIN && !JUNO_AARCH32_EL3_RUNTIME */
 
@@ -438,8 +423,8 @@
 # elif ARM_TSP_RAM_LOCATION_ID == ARM_TRUSTED_SRAM_ID
 #  define TSP_SEC_MEM_BASE		ARM_BL_RAM_BASE
 #  define TSP_SEC_MEM_SIZE		ARM_BL_RAM_SIZE
-#  define TSP_PROGBITS_LIMIT		BL2_BASE
-#  define BL32_BASE			ARM_BL_RAM_BASE
+#  define TSP_PROGBITS_LIMIT		BL31_BASE
+#  define BL32_BASE			ARM_TB_FW_CONFIG_LIMIT
 #  define BL32_LIMIT			BL31_BASE
 # elif ARM_TSP_RAM_LOCATION_ID == ARM_TRUSTED_DRAM_ID
 #  define TSP_SEC_MEM_BASE		PLAT_ARM_TRUSTED_DRAM_BASE
diff --git a/include/plat/arm/css/common/css_def.h b/include/plat/arm/css/common/css_def.h
index 6d68b4406..725c27cbc 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 */
diff --git a/plat/arm/board/fvp/platform.mk b/plat/arm/board/fvp/platform.mk
index c02831ac3..f807dc6e4 100644
--- a/plat/arm/board/fvp/platform.mk
+++ b/plat/arm/board/fvp/platform.mk
@@ -225,12 +225,6 @@ ifneq (${BL2_AT_EL3}, 0)
     override BL1_SOURCES =
 endif
 
-ifeq (${ENABLE_SPM},1)
-ifneq (${ARM_BL31_IN_DRAM},1)
-        $(error "Error: SPM needs BL31 to be located in DRAM.")
-endif
-endif
-
 include plat/arm/board/common/board_common.mk
 include plat/arm/common/arm_common.mk
 
diff --git a/plat/arm/board/juno/include/platform_def.h b/plat/arm/board/juno/include/platform_def.h
index e616e1fcf..75ee991ca 100644
--- a/plat/arm/board/juno/include/platform_def.h
+++ b/plat/arm/board/juno/include/platform_def.h
@@ -139,22 +139,21 @@
 #endif
 
 /*
- * PLAT_ARM_MAX_BL31_SIZE is calculated using the current BL31 debug size plus a
- * little space for growth.
- * SCP_BL2 image is loaded into the space BL31 -> BL1_RW_BASE.
- * For TBB use case, PLAT_ARM_MAX_BL1_RW_SIZE has been increased and therefore
- * PLAT_ARM_MAX_BL31_SIZE has been increased to ensure SCP_BL2 has the same
- * space available.
+ * Since BL31 NOBITS overlays BL2 and BL1-RW, PLAT_ARM_MAX_BL31_SIZE is
+ * calculated using the current BL31 PROGBITS debug size plus the sizes of
+ * BL2 and BL1-RW.  SCP_BL2 image is loaded into the space BL31 -> BL2_BASE.
+ * Hence the BL31 PROGBITS size should be >= PLAT_CSS_MAX_SCP_BL2_SIZE.
  */
-#define PLAT_ARM_MAX_BL31_SIZE		0x1E000
+#define PLAT_ARM_MAX_BL31_SIZE		0x3E000
 
 #if JUNO_AARCH32_EL3_RUNTIME
 /*
- * PLAT_ARM_MAX_BL32_SIZE is calculated for SP_MIN as the AArch32 Secure
- * Payload. We also need to take care of SCP_BL2 size as well, as the SCP_BL2
- * is loaded into the space BL32 -> BL1_RW_BASE
+ * Since BL32 NOBITS overlays BL2 and BL1-RW, PLAT_ARM_MAX_BL32_SIZE is
+ * calculated using the current BL32 PROGBITS debug size plus the sizes of
+ * BL2 and BL1-RW.  SCP_BL2 image is loaded into the space BL32 -> BL2_BASE.
+ * Hence the BL32 PROGBITS size should be >= PLAT_CSS_MAX_SCP_BL2_SIZE.
  */
-# define PLAT_ARM_MAX_BL32_SIZE		0x1E000
+#define PLAT_ARM_MAX_BL32_SIZE		0x3E000
 #endif
 
 /*
diff --git a/plat/arm/common/arm_bl2_setup.c b/plat/arm/common/arm_bl2_setup.c
index d490f83c8..4ef3a9b0f 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
diff --git a/plat/arm/common/arm_bl31_setup.c b/plat/arm/common/arm_bl31_setup.c
index 551e7002f..46f7ae0e5 100644
--- a/plat/arm/common/arm_bl31_setup.c
+++ b/plat/arm/common/arm_bl31_setup.c
@@ -25,6 +25,11 @@
 static entry_point_info_t bl32_image_ep_info;
 static entry_point_info_t bl33_image_ep_info;
 
+/*
+ * Check that BL31_BASE is above ARM_TB_FW_CONFIG_LIMIT. The reserved page
+ * is required for SOC_FW_CONFIG/TOS_FW_CONFIG passed from BL2.
+ */
+CASSERT(BL31_BASE >= ARM_TB_FW_CONFIG_LIMIT, assert_bl31_base_overflows);
 
 /* Weak definitions may be overridden in specific ARM standard platform */
 #pragma weak bl31_early_platform_setup2
diff --git a/plat/arm/common/arm_dyn_cfg.c b/plat/arm/common/arm_dyn_cfg.c
index 3f0a9b4cf..32a515b56 100644
--- a/plat/arm/common/arm_dyn_cfg.c
+++ b/plat/arm/common/arm_dyn_cfg.c
@@ -143,8 +143,8 @@ void arm_bl2_dyn_cfg_init(void)
 			if (check_uptr_overflow(image_base, image_size) != 0)
 				continue;
 
-			/* Ensure the configs don't overlap with BL2 */
-			if ((image_base > BL2_BASE) || ((image_base + image_size) > BL2_BASE))
+			/* Ensure the configs don't overlap with BL31 */
+			if ((image_base > BL31_BASE) || ((image_base + image_size) > BL31_BASE))
 				continue;
 
 			/* Ensure the configs are loaded in a valid address */
diff --git a/plat/arm/common/sp_min/arm_sp_min_setup.c b/plat/arm/common/sp_min/arm_sp_min_setup.c
index 9a6c0740b..b42e35f3a 100644
--- a/plat/arm/common/sp_min/arm_sp_min_setup.c
+++ b/plat/arm/common/sp_min/arm_sp_min_setup.c
@@ -22,6 +22,11 @@ static entry_point_info_t bl33_image_ep_info;
 #pragma weak sp_min_plat_arch_setup
 #pragma weak plat_arm_sp_min_early_platform_setup
 
+/*
+ * Check that BL32_BASE is above ARM_TB_FW_CONFIG_LIMIT. The reserved page
+ * is required for SOC_FW_CONFIG/TOS_FW_CONFIG passed from BL2.
+ */
+CASSERT(BL32_BASE >= ARM_TB_FW_CONFIG_LIMIT, assert_bl32_base_overflows);
 
 /*******************************************************************************
  * Return a pointer to the 'entry_point_info' structure of the next image for the
diff --git a/plat/arm/css/drivers/scp/css_bom_bootloader.c b/plat/arm/css/drivers/scp/css_bom_bootloader.c
index 42ed30d3d..5268510db 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 @@ typedef struct {
 } 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 1f0cf8e24..671612a80 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_image_xfer(void *image, unsigned int image_size);
 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.
+ * 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 <= 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_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);
 #endif
 
 #endif	/* __CSS_SCP_H__ */