Add support for BL2 in XIP memory
In some use-cases BL2 will be stored in eXecute In Place (XIP) memory,
like BL1. In these use-cases, it is necessary to initialize the RW sections
in RAM, while leaving the RO sections in place. This patch enable this
use-case with a new build option, BL2_IN_XIP_MEM. For now, this option
is only supported when BL2_AT_EL3 is 1.
Signed-off-by: Jiafei Pan <Jiafei.Pan@nxp.com>
diff --git a/docs/porting-guide.rst b/docs/porting-guide.rst
index ff5bb12..12e135f 100644
--- a/docs/porting-guide.rst
+++ b/docs/porting-guide.rst
@@ -217,11 +217,37 @@
- **#define : BL2\_BASE**
Defines the base address in secure RAM where BL1 loads the BL2 binary image.
- Must be aligned on a page-size boundary.
+ Must be aligned on a page-size boundary. This constant is not applicable
+ when BL2_IN_XIP_MEM is set to '1'.
- **#define : BL2\_LIMIT**
Defines the maximum address in secure RAM that the BL2 image can occupy.
+ This constant is not applicable when BL2_IN_XIP_MEM is set to '1'.
+
+- **#define : BL2\_RO\_BASE**
+
+ Defines the base address in secure XIP memory where BL2 RO section originally
+ lives. Must be aligned on a page-size boundary. This constant is only needed
+ when BL2_IN_XIP_MEM is set to '1'.
+
+- **#define : BL2\_RO\_LIMIT**
+
+ Defines the maximum address in secure XIP memory that BL2's actual content
+ (i.e. excluding any data section allocated at runtime) can occupy. This
+ constant is only needed when BL2_IN_XIP_MEM is set to '1'.
+
+- **#define : BL2\_RW\_BASE**
+
+ Defines the base address in secure RAM where BL2's read-write data will live
+ at runtime. Must be aligned on a page-size boundary. This constant is only
+ needed when BL2_IN_XIP_MEM is set to '1'.
+
+- **#define : BL2\_RW\_LIMIT**
+
+ Defines the maximum address in secure RAM that BL2's read-write data can
+ occupy at runtime. This constant is only needed when BL2_IN_XIP_MEM is set
+ to '1'.
- **#define : BL31\_BASE**