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>

1 files changed, 0 insertions, 222 deletions

diff --git a/doc/DocBook/Makefile b/doc/DocBook/Makefile
deleted file mode 100644
index 5257613513..0000000000
--- a/doc/DocBook/Makefile
+++ /dev/null
@@ -1,222 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0
-###
-# This makefile is used to generate the kernel documentation,
-# primarily based on in-line comments in various source files.
-# See Documentation/kernel-doc-nano-HOWTO.txt for instruction in how
-# to document the SRC - and how to read it.
-# To add a new book the only step required is to add the book to the
-# list of DOCBOOKS.
-
-DOCBOOKS := efi.xml linker_lists.xml stdio.xml
-
-###
-# The build process is as follows (targets):
-#              (xmldocs) [by docproc]
-# file.tmpl --> file.xml +--> file.ps   (psdocs)   [by db2ps or xmlto]
-#                        +--> file.pdf  (pdfdocs)  [by db2pdf or xmlto]
-#                        +--> DIR=file  (htmldocs) [by xmlto]
-#                        +--> man/      (mandocs)  [by xmlto]
-
-
-# for PDF and PS output you can choose between xmlto and docbook-utils tools
-PDF_METHOD	= $(prefer-db2x)
-PS_METHOD	= $(prefer-db2x)
-
-
-###
-# The targets that may be used.
-PHONY += xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs cleandocs
-
-targets += $(DOCBOOKS)
-BOOKS := $(addprefix $(obj)/,$(DOCBOOKS))
-xmldocs: $(BOOKS)
-sgmldocs: xmldocs
-
-PS := $(patsubst %.xml, %.ps, $(BOOKS))
-psdocs: $(PS)
-
-PDF := $(patsubst %.xml, %.pdf, $(BOOKS))
-pdfdocs: $(PDF)
-
-HTML := $(sort $(patsubst %.xml, %.html, $(BOOKS)))
-htmldocs: $(HTML)
-	$(call build_main_index)
-	$(call build_images)
-	$(call install_media_images)
-
-MAN := $(patsubst %.xml, %.9, $(BOOKS))
-mandocs: $(MAN)
-	$(if $(wildcard $(obj)/man/*.9),gzip -f $(obj)/man/*.9)
-
-installmandocs: mandocs
-	mkdir -p /usr/local/man/man9/
-	install $(obj)/man/*.9.gz /usr/local/man/man9/
-
-###
-#External programs used
-KERNELDOC = $(srctree)/scripts/kernel-doc
-DOCPROC   = $(objtree)/scripts/docproc
-
-XMLTOFLAGS = -m $(srctree)/$(src)/stylesheet.xsl
-XMLTOFLAGS += --skip-validation
-
-###
-# DOCPROC is used for two purposes:
-# 1) To generate a dependency list for a .tmpl file
-# 2) To preprocess a .tmpl file and call kernel-doc with
-#     appropriate parameters.
-# The following rules are used to generate the .xml documentation
-# required to generate the final targets. (ps, pdf, html).
-quiet_cmd_docproc = DOCPROC $@
-      cmd_docproc = SRCTREE=$(srctree)/ $(DOCPROC) doc $< >$@
-define rule_docproc
-	set -e;								\
-        $(if $($(quiet)cmd_$(1)),echo '  $($(quiet)cmd_$(1))';) 	\
-        $(cmd_$(1)); 							\
-        ( 								\
-          echo 'cmd_$@ := $(cmd_$(1))'; 				\
-          echo $@: `SRCTREE=$(srctree) $(DOCPROC) depend $<`; 		\
-        ) > $(dir $@).$(notdir $@).cmd
-endef
-
-%.xml: %.tmpl $(KERNELDOC) $(DOCPROC) FORCE
-	$(call if_changed_rule,docproc)
-
-# Tell kbuild to always build the programs
-always := $(hostprogs-y)
-
-notfoundtemplate = echo "*** You have to install docbook-utils or xmlto ***"; \
-		   exit 1
-db2xtemplate = db2TYPE -o $(dir $@) $<
-xmltotemplate = xmlto TYPE $(XMLTOFLAGS) -o $(dir $@) $<
-
-# determine which methods are available
-ifeq ($(shell which db2ps >/dev/null 2>&1 && echo found),found)
-	use-db2x = db2x
-	prefer-db2x = db2x
-else
-	use-db2x = notfound
-	prefer-db2x = $(use-xmlto)
-endif
-ifeq ($(shell which xmlto >/dev/null 2>&1 && echo found),found)
-	use-xmlto = xmlto
-	prefer-xmlto = xmlto
-else
-	use-xmlto = notfound
-	prefer-xmlto = $(use-db2x)
-endif
-
-# the commands, generated from the chosen template
-quiet_cmd_db2ps = PS      $@
-      cmd_db2ps = $(subst TYPE,ps, $($(PS_METHOD)template))
-%.ps : %.xml
-	$(call cmd,db2ps)
-
-quiet_cmd_db2pdf = PDF     $@
-      cmd_db2pdf = $(subst TYPE,pdf, $($(PDF_METHOD)template))
-%.pdf : %.xml
-	$(call cmd,db2pdf)
-
-
-index = index.html
-main_idx = $(obj)/$(index)
-build_main_index = rm -rf $(main_idx); \
-		   echo '<h1>U-Boot Bootloader HTML Documentation</h1>' >> $(main_idx) && \
-		   echo '<h2>U-Boot Version: $(UBOOTVERSION)</h2>' >> $(main_idx) && \
-		   cat $(HTML) >> $(main_idx)
-
-quiet_cmd_db2html = HTML    $@
-      cmd_db2html = xmlto html $(XMLTOFLAGS) -o $(patsubst %.html,%,$@) $< && \
-		echo '<a HREF="$(patsubst %.html,%,$(notdir $@))/index.html"> \
-		$(patsubst %.html,%,$(notdir $@))</a><p>' > $@
-
-%.html:	%.xml
-	@(which xmlto > /dev/null 2>&1) || \
-	 (echo "*** You need to install xmlto ***"; \
-	  exit 1)
-	@rm -rf $@ $(patsubst %.html,%,$@)
-	$(call cmd,db2html)
-	@if [ ! -z "$(PNG-$(basename $(notdir $@)))" ]; then \
-            cp $(PNG-$(basename $(notdir $@))) $(patsubst %.html,%,$@); fi
-
-quiet_cmd_db2man = MAN     $@
-      cmd_db2man = if grep -q refentry $<; then xmlto man $(XMLTOFLAGS) -o $(obj)/man $< ; fi
-%.9 : %.xml
-	@(which xmlto > /dev/null 2>&1) || \
-	 (echo "*** You need to install xmlto ***"; \
-	  exit 1)
-	$(Q)mkdir -p $(obj)/man
-	$(call cmd,db2man)
-	@touch $@
-
-###
-# Rules to generate postscripts and PNG images from .fig format files
-quiet_cmd_fig2eps = FIG2EPS $@
-      cmd_fig2eps = fig2dev -Leps $< $@
-
-%.eps: %.fig
-	@(which fig2dev > /dev/null 2>&1) || \
-	 (echo "*** You need to install transfig ***"; \
-	  exit 1)
-	$(call cmd,fig2eps)
-
-quiet_cmd_fig2png = FIG2PNG $@
-      cmd_fig2png = fig2dev -Lpng $< $@
-
-%.png: %.fig
-	@(which fig2dev > /dev/null 2>&1) || \
-	 (echo "*** You need to install transfig ***"; \
-	  exit 1)
-	$(call cmd,fig2png)
-
-###
-# Rule to convert a .c file to inline XML documentation
-       gen_xml = :
- quiet_gen_xml = echo '  GEN     $@'
-silent_gen_xml = :
-%.xml: %.c
-	@$($(quiet)gen_xml)
-	@(                            \
-	   echo "<programlisting>";   \
-	   expand --tabs=8 < $< |     \
-	   sed -e "s/&/\\&amp;/g"     \
-	       -e "s/</\\&lt;/g"      \
-	       -e "s/>/\\&gt;/g";     \
-	   echo "</programlisting>")  > $@
-
-###
-# Help targets as used by the top-level makefile
-dochelp:
-	@echo  ' U-Boot bootloader internal documentation in different formats:'
-	@echo  '  htmldocs        - HTML'
-	@echo  '  pdfdocs         - PDF'
-	@echo  '  psdocs          - Postscript'
-	@echo  '  xmldocs         - XML DocBook'
-	@echo  '  mandocs         - man pages'
-	@echo  '  installmandocs  - install man pages generated by mandocs'
-	@echo  '  cleandocs       - clean all generated DocBook files'
-
-###
-# Temporary files left by various tools
-clean-files := $(DOCBOOKS) \
-	$(patsubst %.xml, %.dvi,  $(DOCBOOKS)) \
-	$(patsubst %.xml, %.aux,  $(DOCBOOKS)) \
-	$(patsubst %.xml, %.tex,  $(DOCBOOKS)) \
-	$(patsubst %.xml, %.log,  $(DOCBOOKS)) \
-	$(patsubst %.xml, %.out,  $(DOCBOOKS)) \
-	$(patsubst %.xml, %.ps,   $(DOCBOOKS)) \
-	$(patsubst %.xml, %.pdf,  $(DOCBOOKS)) \
-	$(patsubst %.xml, %.html, $(DOCBOOKS)) \
-	$(patsubst %.xml, %.9,    $(DOCBOOKS)) \
-	$(index)
-
-clean-dirs := $(patsubst %.xml,%,$(DOCBOOKS)) man
-
-cleandocs:
-	$(Q)rm -f $(call objectify, $(clean-files))
-	$(Q)rm -rf $(call objectify, $(clean-dirs))
-
-# Declare the contents of the .PHONY variable as phony.  We keep that
-# information in a variable se we can use it in if_changed and friends.
-
-.PHONY: $(PHONY)