kbuild: doc: update the description about Kbuild/Makefile split

The phrase "In newer versions of the kernel" was added 14 years ago, by
commit efdf02cf0651 ("Documentation/kbuild: major edit of modules.txt
sections 1-4"). This feature is no longer new, so remove it and update
the paragraph.

Example 3 was written 20 years ago [1]. There is no need to note about
backward compatibility with such an old build system. Remove Example 3
entirely.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=65e433436b5794ae056d22ddba60fe9194bba007

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>

diff --git a/Documentation/kbuild/modules.rst b/Documentation/kbuild/modules.rst
index 1318631..1014a27 100644 (file)
--- a/Documentation/kbuild/modules.rst
+++ b/Documentation/kbuild/modules.rst
@@ -224,10 +224,9 @@ module 8123.ko, which is built from the following files::
 3.2 Separate Kbuild File and Makefile
 -------------------------------------
 
-       In newer versions of the kernel, kbuild will first look for a
-       file named "Kbuild," and only if that is not found, will it
-       then look for a makefile. Utilizing a "Kbuild" file allows us
-       to split up the makefile from example 1 into two files:
+       Kbuild will first look for a file named "Kbuild", and if it is not
+       found, it will then look for "Makefile". Utilizing a "Kbuild" file
+       allows us to split up the "Makefile" from example 1 into two files:
 
        Example 2::
 
@@ -250,37 +249,6 @@ module 8123.ko, which is built from the following files::
        consisting of several hundred lines, and here it really pays
        off to separate the kbuild part from the rest.
 
-       The next example shows a backward compatible version.
-
-       Example 3::
-
-               --> filename: Kbuild
-               obj-m  := 8123.o
-               8123-y := 8123_if.o 8123_pci.o 8123_bin.o
-
-               --> filename: Makefile
-               ifneq ($(KERNELRELEASE),)
-               # kbuild part of makefile
-               include Kbuild
-
-               else
-               # normal makefile
-               KDIR ?= /lib/modules/`uname -r`/build
-
-               default:
-                       $(MAKE) -C $(KDIR) M=$$PWD
-
-               # Module specific targets
-               genbin:
-                       echo "X" > 8123_bin.o_shipped
-
-               endif
-
-       Here the "Kbuild" file is included from the makefile. This
-       allows an older version of kbuild, which only knows of
-       makefiles, to be used when the "make" and kbuild parts are
-       split into separate files.
-
 3.3 Binary Blobs
 ----------------