Two pass build for on-demand paging now works

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@2896 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 26 insertions, 3 deletions

diff --git a/nuttx/configs/README.txt b/nuttx/configs/README.txt
index c1b73b310..6603c9848 100644
--- a/nuttx/configs/README.txt
+++ b/nuttx/configs/README.txt
@@ -139,7 +139,7 @@ defconfig -- This is a configuration file similar to the Linux
 		CONFIG_DRAM_START - The start address of DRAM (physical)
 		CONFIG_DRAM_VSTART - The start address of DRAM (virtual)
 
-	General build options
+	General build options:
 
 		CONFIG_RRLOAD_BINARY - make the rrload binary format used with
 		  BSPs from www.ridgerun.com using the tools/mkimage.sh script.
@@ -157,7 +157,7 @@ defconfig -- This is a configuration file similar to the Linux
 		  COMPILEXX have been defined in the configuratins Make.defs
 		  file.
 
-	General OS setup
+	Building application code:
 
 		CONFIG_APP_DIR - Identifies the directory that builds the
 		  application to link with NuttX. This symbol must be assigned
@@ -201,6 +201,28 @@ defconfig -- This is a configuration file similar to the Linux
 		  example, to include makefile fragments (e.g., .config or Make.defs)
 		  or to set up include file paths.
 
+	Two-pass build options.  If the 2 pass build option is selected, then these
+	options configure the make system build a extra link object. This link object
+	is assumed to be an incremental (relative) link object, but could be a static
+	library (archive) (some modification to this Makefile would be required if
+	CONFIG_PASS1_OBJECT is an archive). Pass 1 1ncremental (relative) link objects
+	should be put into the processor-specific source directory (where other
+	link objects will be created).  If the pass1 obect is an archive, it could
+	go anywhere.
+
+		CONFIG_BUILD_2PASS - Enables the two pass build options.
+
+	When the two pass build option is enabled, the following also apply:
+
+		CONFIG_PASS1_OBJECT - The name of the first pass object.
+		CONFIG_PASS1_BUILDIR - The path, relative to the top NuttX build
+		  directory to directory that contains the Makefile to build the
+		  first pass object.  The Makefile must support the following targets:
+		  - The special target arch/$(CONFIG_ARCH)/src/$(CONFIG_PASS1_OBJECT)
+		  - and the usual depend, clean, and distclean targets.
+
+	General OS setup
+
 		CONFIG_DEBUG - enables built-in debug options
 		CONFIG_DEBUG_VERBOSE - enables verbose debug output
 		CONFIG_DEBUG_SYMBOLS - build without optimization and with
@@ -308,7 +330,8 @@ defconfig -- This is a configuration file similar to the Linux
 		  enable the on-demand paging feature as described in
 		  http://www.nuttx.org/NuttXDemandPaging.html.
 
-    If CONFIG_PAGING is selected, then the following also apply:
+    If CONFIG_PAGING is selected, then you will probabaly need CONFIG_BUILD_2PASS to
+    correctly position the code and the following configuration options also apply:
 
 		CONFIG_PAGING_PAGESIZE - The size of one managed page.  This must
 		  be a value supported by the processor's memory management unit.