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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/tools/build/Documentation
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/tools/build/Documentation')
-rw-r--r--kernel/tools/build/Documentation/Build.txt53
1 files changed, 40 insertions, 13 deletions
diff --git a/kernel/tools/build/Documentation/Build.txt b/kernel/tools/build/Documentation/Build.txt
index 00ad2d608..a47bffbae 100644
--- a/kernel/tools/build/Documentation/Build.txt
+++ b/kernel/tools/build/Documentation/Build.txt
@@ -11,8 +11,9 @@ Unlike the kernel we don't have a single build object 'obj-y' list that where
we setup source objects, but we support more. This allows one 'Build' file to
carry a sources list for multiple build objects.
-a) Build framework makefiles
-----------------------------
+
+Build framework makefiles
+-------------------------
The build framework consists of 2 Makefiles:
@@ -23,7 +24,7 @@ While the 'Build.include' file contains just some generic definitions, the
'Makefile.build' file is the makefile used from the outside. It's
interface/usage is following:
- $ make -f tools/build/Makefile srctree=$(KSRC) dir=$(DIR) obj=$(OBJECT)
+ $ make -f tools/build/Makefile.build srctree=$(KSRC) dir=$(DIR) obj=$(OBJECT)
where:
@@ -38,8 +39,9 @@ called $(OBJECT)-in.o:
which includes all compiled sources described in 'Build' makefiles.
-a) Build makefiles
-------------------
+
+Build makefiles
+---------------
The user supplies 'Build' makefiles that contains a objects list, and connects
the build to nested directories.
@@ -66,6 +68,7 @@ To follow the above example, the user provides following 'Build' files:
ex/Build:
ex-y += a.o
ex-y += b.o
+ ex-y += b.o # duplicates in the lists are allowed
libex-y += c.o
libex-y += d.o
@@ -94,8 +97,31 @@ It's only a matter of 2 single commands to create the final binaries:
You can check the 'ex' example in 'tools/build/tests/ex' for more details.
-b) Rules
---------
+
+Makefile.include
+----------------
+
+The tools/build/Makefile.include makefile could be included
+via user makefiles to get usefull definitions.
+
+It defines following interface:
+
+ - build macro definition:
+ build := -f $(srctree)/tools/build/Makefile.build dir=. obj
+
+ to make it easier to invoke build like:
+ make $(build)=ex
+
+
+Fixdep
+------
+It is necessary to build the fixdep helper before invoking the build.
+The Makefile.include file adds the fixdep target, that could be
+invoked by the user.
+
+
+Rules
+-----
The build framework provides standard compilation rules to handle .S and .c
compilation.
@@ -103,8 +129,9 @@ compilation.
It's possible to include special rule if needed (like we do for flex or bison
code generation).
-c) CFLAGS
----------
+
+CFLAGS
+------
It's possible to alter the standard object C flags in the following way:
@@ -114,8 +141,8 @@ It's possible to alter the standard object C flags in the following way:
This C flags changes has the scope of the Build makefile they are defined in.
-d) Dependencies
----------------
+Dependencies
+------------
For each built object file 'a.o' the '.a.cmd' is created and holds:
@@ -129,8 +156,8 @@ All existing '.cmd' files are included in the Build process to follow properly
the dependencies and trigger a rebuild when necessary.
-e) Single rules
----------------
+Single rules
+------------
It's possible to build single object file by choice, like: