comments welcome. This doc is in the RFC section.
ron New config language for LinuxBIOS
\begin{abstract} We describe the new configuration language for LinuxBIOS. \end{abstract}
\section{Scope} This document defines the new configuration language for LinuxBIOS.
\section{Goals} The goals of the new language are these: \begin{itemize} \item Simplified Makefiles so people can see what is set \item Move from the regular-expression-based language to something a bit more comprehensible and flexible \item make the specification easier for people to use and understand \item allow unique register-set-specifiers for each chip \end{itemize}
\section{Language} Here is the new language. It is very similar to the old one, differing in only a few respects. It borrows heavily from Greg Watson's suggestions.
I am presenting it in a pseudo-BNF in the hopes it will be easier. Things in '' are keywords; things in ``'' are strings in the actual text. \begin{verbatim} #exprs are composed of factor or factor + factor etc. expr ::= factor ( ``+'' factor | ``-'' factor | )* #factors are term or term * term or term / term or ... factor ::= term ( ``*'' term | ``/'' term | ... )* # unary-op ::= ``!'' ID # term is a number, hexnumber, ID, unary-op, or a full-blown expression term ::= NUM | XNUM | ID | unary-op | ``(`` expr ``)''
# Option command. Can be an expression or quote-string. # Options are used in the config tool itself (in expressions and 'if') # and are also passed to the C compiler when building linuxbios. # It is an error to have two option commands in a file. # It is an error to have an option command after the ID has been used # in an expression (i.e. 'set after used' is an error) option ::= 'option' ID '=' (``value'' | term)
# Default command. The ID is set to this value if no option command # is scanned. # Multiple defaults for an ID will produce warning, but not errors. # It is OK to scan a default command after use of an ID. # Options always over-ride defaults. default ::= 'default' ID '=' (``value'' | term)
# the mainboard, southbridge, northbridge commands # cause sourcing of Config.lb files as in the old config tool # as parts are sourced, a device tree is built. The structure # of the tree is determined by the structure of the components # as they are specified. To attach a superio to a southbridge, for # example, one would do this: # southbridge acer/5432 # superio NSC/123 # end # end # the tool generates static initializers for this hierarchy.
# add C code to the current component (motherboard, etc. ) # to initialise the component-INDEPENDENT structure members init ::= 'init' ``CODE''
# add C code to the current component (motherboard, etc. ) # to initialise the component-DEPENDENT structure members register ::= 'register' ``CODE''
# mainboard command # statements in this block will set variables controlling the mainboard, # and will also place components (northbridge etc.) in the device tree # under this mainboard mainboard ::= 'mainboard' PATH (statements)* 'end'
# standard linuxbios commands southbridge ::= 'southbridge' PATH (statemnts)* 'end' northbridge ::= 'northbridge' PATH (statemnts)* 'end' superio ::= 'superio PATH (statemnts)* 'end' cpu ::= 'cpu' PATH (statemnts)* 'end' arch ::= 'arch' PATH (statemnts)* 'end'
# files for building linuxbios # include a file in crt0.S mainboardinit ::= 'mainboardinit' PATH
# object file object ::= 'object' PATH # driver objects are just built into the image in a different way driver ::= 'driver' PATH
# Use the Config.lb file in the PATH dir ::= 'dir' PATH
# add a file to the set of ldscript files ldscript ::= 'ldscript' PATH
# dependencies or actions for the makerule command dep ::= 'dep' ``dependency-string'' act ::= 'act' ``actions'' depsacts ::= (dep | act)* # set up a makerule # makerule ::= 'makerule' PATH depsacts
#defines for use in makefiles only # note usable in the config tool, not passed to cc makedefine ::= 'makedefine' ``RAWTEXT''
# add an action to an existing make rule addaction ::= 'addaction' PATH ``ACTION''
# statements statement ::= option | default | cpu | arch | northbridge | southbridge | superio | object | driver | mainboardinit | makerule | makedefine | addaction | init | register | iif | dir | ldscript
statements ::= (statement)*
# target directory specification target ::= 'target' PATH
# and the whole thing board ::= target (option)* mainboard
\end{verbatim}
A sample file:
\begin{verbatim} target x
# over-ride the default rom size in the mainboard file option ROM_SIZE=0x100000 mainboard amd/solo end
\end{verbatim}
Sample mainboard file \begin{verbatim} # ### ### Set all of the defaults for an x86 architecture ### arch i386 end cpu k8 end # option DEBUG=1 default USE_FALLBACK_IMAGE=1 option A=(1+2) option B=0xa # ### ### Build our 16 bit and 32 bit linuxBIOS entry code ### mainboardinit cpu/i386/entry16.inc mainboardinit cpu/i386/entry32.inc ldscript cpu/i386/entry16.lds ldscript cpu/i386/entry32.lds # ### ### Build our reset vector (This is where linuxBIOS is entered) ### if USE_FALLBACK_IMAGE mainboardinit cpu/i386/reset16.inc ldscript cpu/i386/reset16.lds end
if USE_NORMAL_IMAGE mainboardinit cpu/i386/reset32.inc ldscript cpu/i386/reset32.lds end . . . if USE_FALLBACK_IMAGE mainboardinit arch/i386/lib/noop_failover.inc end # ### ### Romcc output ### #makerule ./failover.E dep "$(MAINBOARD)/failover.c" act "$(CPP) -I$(TOP)/src $(CPPFLAGS) $(MAINBOARD)/failover.c > ./failever.E" #makerule ./failover.inc dep "./romcc ./failover.E" act "./romcc -O ./failover.E > failover.inc" #mainboardinit ./failover.inc makerule ./auto.E dep "$(MAINBOARD)/auto.c" act "$(CPP) -I$(TOP)/src -$(ROMCCPPFLAGS) $(CPPFLAGS) $(MAINBOARD)/auto.c > ./auto.E" makerule ./auto.inc dep "./romcc ./auto.E" act "./romcc -O ./auto.E > auto.inc" mainboardinit ./auto.inc # ### ### Setup RAM ### mainboardinit ram/ramtest.inc mainboardinit southbridge/amd/amd8111/smbus.inc mainboardinit sdram/generic_dump_spd.inc # ### ### Include the secondary Configuration files ### northbridge amd/amdk8 end southbridge amd/amd8111 end #mainboardinit arch/i386/smp/secondary.inc superio NSC/pc87360 register "com1={1} com2={0} floppy=1 lpt=1 keyboard=1" end dir /pc80 ##dir /src/superio/winbond/w83627hf cpu p5 end cpu p6 end cpu k7 end cpu k8 end # ### ### Build the objects we have code for in this directory. ### ##object mainboard.o driver mainboard.o object static_devices.o if HAVE_MP_TABLE object mptable.o end if HAVE_PIRQ_TABLE object irq_tables.o end ### Location of the DIMM EEPROMS on the SMBUS ### This is fixed into a narrow range by the DIMM package standard. ### option SMBUS_MEM_DEVICE_START=(0xa << 3) option SMBUS_MEM_DEVICE_END=(SMBUS_MEM_DEVICE_START +1) option SMBUS_MEM_DEVICE_INC=1 # ### The linuxBIOS bootloader. ### option PAYLOAD_SIZE = (ROM_SECTION_SIZE - ROM_IMAGE_SIZE) option CONFIG_ROM_STREAM_START = (0xffffffff - ROM_SIZE + ROM_SECTION_OFFSET + 1) #
\end{verbatim}
I've found the output of the new tool to be easier to handle. Makefile.settings looks like this, for example: \begin{verbatim} TOP:=/home/rminnich/src/yapps2/freebios2 TARGET_DIR:=x export MAINBOARD:=/home/rminnich/src/yapps2/freebios2/src/mainboard/amd/solo export ARCH:=i386 export _RAMBASE:=0x4000 export ROM_IMAGE_SIZE:=65535 export PAYLOAD_SIZE:=131073 export MAX_CPUS:=1 export HEAP_SIZE:=8192 export STACK_SIZE:=8192 export MEMORY_HOLE:=0 export LINUXBIOS_VERSION:=1.1.0 export CC:=$(CROSS_COMPILE)gcc
\end{verbatim}
In other words, instead of expressions, we see the values. It's easier to deal with.