doc: Replace DocBook with sphinx-based docs
The Linux kernel moved to sphinx-based documentation and got rid of the
DocBook based documentation quite a while ago. Hence, the DocBook
documentation for U-Boot should be converted as well.
To achieve this, import the necessary files from Linux v4.17, and
convert the current DocBook documentation (three files altogether) to
sphinx/reStructuredText.
For now, all old DocBook documentation was merged into a single
handbook, tentatively named "U-Boot Hacker Manual".
For some source files, the documentation style was changed to comply
with kernel-doc; no functional changes were applied.
Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/Documentation/Makefile b/Documentation/Makefile
new file mode 100644
index 0000000..2ca77ad
--- /dev/null
+++ b/Documentation/Makefile
@@ -0,0 +1,124 @@
+# -*- makefile -*-
+# Makefile for Sphinx documentation
+#
+
+subdir-y :=
+
+# You can set these variables from the command line.
+SPHINXBUILD = sphinx-build
+SPHINXOPTS =
+SPHINXDIRS = .
+_SPHINXDIRS = $(patsubst $(srctree)/Documentation/%/conf.py,%,$(wildcard $(srctree)/Documentation/*/conf.py))
+SPHINX_CONF = conf.py
+PAPER =
+BUILDDIR = $(obj)/output
+PDFLATEX = xelatex
+LATEXOPTS = -interaction=batchmode
+
+# User-friendly check for sphinx-build
+HAVE_SPHINX := $(shell if which $(SPHINXBUILD) >/dev/null 2>&1; then echo 1; else echo 0; fi)
+
+ifeq ($(HAVE_SPHINX),0)
+
+.DEFAULT:
+ $(warning The '$(SPHINXBUILD)' command was not found. Make sure you have Sphinx installed and in PATH, or set the SPHINXBUILD make variable to point to the full path of the '$(SPHINXBUILD)' executable.)
+ @echo
+ @./scripts/sphinx-pre-install
+ @echo " SKIP Sphinx $@ target."
+
+else # HAVE_SPHINX
+
+# User-friendly check for pdflatex
+HAVE_PDFLATEX := $(shell if which $(PDFLATEX) >/dev/null 2>&1; then echo 1; else echo 0; fi)
+
+# Internal variables.
+PAPEROPT_a4 = -D latex_paper_size=a4
+PAPEROPT_letter = -D latex_paper_size=letter
+KERNELDOC = $(srctree)/scripts/kernel-doc
+KERNELDOC_CONF = -D kerneldoc_srctree=$(srctree) -D kerneldoc_bin=$(KERNELDOC)
+ALLSPHINXOPTS = $(KERNELDOC_CONF) $(PAPEROPT_$(PAPER)) $(SPHINXOPTS)
+# the i18n builder cannot share the environment and doctrees with the others
+I18NSPHINXOPTS = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
+
+# commands; the 'cmd' from scripts/Kbuild.include is not *loopable*
+loop_cmd = $(echo-cmd) $(cmd_$(1)) || exit;
+
+# $2 sphinx builder e.g. "html"
+# $3 name of the build subfolder / e.g. "media", used as:
+# * dest folder relative to $(BUILDDIR) and
+# * cache folder relative to $(BUILDDIR)/.doctrees
+# $4 dest subfolder e.g. "man" for man pages at media/man
+# $5 reST source folder relative to $(srctree)/$(src),
+# e.g. "media" for the linux-tv book-set at ./Documentation/media
+
+quiet_cmd_sphinx = SPHINX $@ --> file://$(abspath $(BUILDDIR)/$3/$4)
+ cmd_sphinx = $(MAKE) BUILDDIR=$(abspath $(BUILDDIR)) $(build)=Documentation/media $2 && \
+ PYTHONDONTWRITEBYTECODE=1 \
+ BUILDDIR=$(abspath $(BUILDDIR)) SPHINX_CONF=$(abspath $(srctree)/$(src)/$5/$(SPHINX_CONF)) \
+ $(SPHINXBUILD) \
+ -b $2 \
+ -c $(abspath $(srctree)/$(src)) \
+ -d $(abspath $(BUILDDIR)/.doctrees/$3) \
+ -D version=$(KERNELVERSION) -D release=$(KERNELRELEASE) \
+ $(ALLSPHINXOPTS) \
+ $(abspath $(srctree)/$(src)/$5) \
+ $(abspath $(BUILDDIR)/$3/$4)
+
+htmldocs:
+ @+$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,html,$(var),,$(var)))
+
+linkcheckdocs:
+ @$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,linkcheck,$(var),,$(var)))
+
+latexdocs:
+ @+$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,latex,$(var),latex,$(var)))
+
+ifeq ($(HAVE_PDFLATEX),0)
+
+pdfdocs:
+ $(warning The '$(PDFLATEX)' command was not found. Make sure you have it installed and in PATH to produce PDF output.)
+ @echo " SKIP Sphinx $@ target."
+
+else # HAVE_PDFLATEX
+
+pdfdocs: latexdocs
+ $(foreach var,$(SPHINXDIRS), $(MAKE) PDFLATEX=$(PDFLATEX) LATEXOPTS="$(LATEXOPTS)" -C $(BUILDDIR)/$(var)/latex || exit;)
+
+endif # HAVE_PDFLATEX
+
+epubdocs:
+ @+$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,epub,$(var),epub,$(var)))
+
+xmldocs:
+ @+$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,xml,$(var),xml,$(var)))
+
+endif # HAVE_SPHINX
+
+# The following targets are independent of HAVE_SPHINX, and the rules should
+# work or silently pass without Sphinx.
+
+refcheckdocs:
+ $(Q)cd $(srctree);scripts/documentation-file-ref-check
+
+cleandocs:
+ $(Q)rm -rf $(BUILDDIR)
+ $(Q)$(MAKE) BUILDDIR=$(abspath $(BUILDDIR)) $(build)=Documentation/media clean
+
+dochelp:
+ @echo ' Linux kernel internal documentation in different formats from ReST:'
+ @echo ' htmldocs - HTML'
+ @echo ' latexdocs - LaTeX'
+ @echo ' pdfdocs - PDF'
+ @echo ' epubdocs - EPUB'
+ @echo ' xmldocs - XML'
+ @echo ' linkcheckdocs - check for broken external links (will connect to external hosts)'
+ @echo ' refcheckdocs - check for references to non-existing files under Documentation'
+ @echo ' cleandocs - clean all generated files'
+ @echo
+ @echo ' make SPHINXDIRS="s1 s2" [target] Generate only docs of folder s1, s2'
+ @echo ' valid values for SPHINXDIRS are: $(_SPHINXDIRS)'
+ @echo
+ @echo ' make SPHINX_CONF={conf-file} [target] use *additional* sphinx-build'
+ @echo ' configuration. This is e.g. useful to build with nit-picking config.'
+ @echo
+ @echo ' Default location for the generated documents is Documentation/output'