#@TYPE: Machine
#@NAME: Linksys NSLU2
#@DESCRIPTION: Machine configuration for the Linksys NSLU2 product

# NOTE: conf/${DISTRO}.conf is included after this file and may be
# used to modify variables set here.

#-------------------------------------------------------------------------------
# Processor and compilation options
#-------------------------------------------------------------------------------
#OVERRIDES
# ARM processors support both 32('arm') and 16('thumb') bit instruction sets,
# The procedure call standard has special provision for inter-calling without
# the need to know whether the instruction set of the target procedure
# ('interwork').  These options control the instruction set and whether or not
# interworking is supported.
#
# ARM_INTERWORK may be set to :thumb-interwork if required, empty otherwise.
# ARM_THUMB may be set to ":thumb" (exactly that, with the leading :) if thumb
#  instructions are required, empty otherwise.
#
# These two variables define the instruction set used for compilation and
# whether the other (16 or 32 bit) instruction set is supported by the distro.
# These options may be changed on a per-package basis, however interwork is
# required if the package instruction set does not match the distro option.
# To set these in a package simply set the relevant variable to the correct
# value, in each case *non-empty* means 'true' - -mthumb-interwork or -mthumb
# in the compilation options.
#ARM_INTERWORK = ":thumb-interwork"
ARM_INTERWORK = ""
#ARM_INSTRUCTION_SET = ":thumb"
ARM_INSTRUCTION_SET = ""

# The OVERRIDES are modified here so that 'NSLU2_BASE_DISTRO' overrides are
# picked up if present (${DISTRO} overrides take precedence), ARM_INTERWORK
# and ARM_INSTRUCTION_SET overrides are for handling bugs in packages which
# cannot deal with the -mthumb-interwork or -mthumb settings.
#NSLU2_BASE_DISTRO = ":openslug"
NSLU2_BASE_DISTRO = ""
OVERRIDES = "local:${MACHINE}:${DISTRO}${NSLU2_BASE_DISTRO}:${TARGET_OS}:${TARGET_ARCH}${ARM_INSTRUCTION_SET}${ARM_INTERWORK}:build-${BUILD_OS}"

#COMPILER
# Compiler options - passed to TARGET_CC_ARCH
ARM_INTERWORK_M_OPT = "${@['-mthumb-interwork', '-mno-thumb-interwork'][bb.data.getVar('ARM_INTERWORK', d, 1) == '']}"
ARM_THUMB_M_OPT = "${@['-mthumb', '-mno-thumb'][bb.data.getVar('ARM_INSTRUCTION_SET', d, 1) == '']}"

# This was 'include tune-xscale.conf' but that doesn't work
# (it would need to be conf/machine/tune-xscale.conf) and
# anyway it sets the package architecture to armeb.
TARGET_CC_ARCH = "-march=armv5te -mtune=xscale ${ARM_INTERWORK_M_OPT} ${ARM_THUMB_M_OPT}"
TARGET_CC_KERNEL_ARCH = "-march=armv5te -mtune=xscale -mno-thumb-interwork -mno-thumb"
TARGET_LD_ARCH = ""
TARGET_LD_KERNEL_ARCH = ""

# Optimization settings.  Os works fine and is significantly
# better than O2.  The other settings are somewhat arbitrary.
# The optimisations chosen here include the ones which 'break'
# symbolic debugging (because the compiler does not include
# enough information to allow the debugger to know where given
# values are.)  The -fno options are an attempt to cancel explicit
# use of space consuming options found in some packages (this isn't
# a complete list, this is just the ones which package writers seem
# to know about and abuse).
FULL_OPTIMIZATION = "-Os -fomit-frame-pointer -frename-registers \
	-fno-unroll-loops -fno-inline-functions \
	-fweb -funit-at-a-time"

# uClibc does not include sinf or cosf, so the gcc auto-use of 
# these functions must be disabled (this only occurs with -O)
FULL_OPTIMIZATION_append_linux-uclibc = " -fno-builtin-sin -fno-builtin-cos"

#-------------------------------------------------------------------------------
# 'ARCH' options - package architecture and the 'target' architecture
#-------------------------------------------------------------------------------
# Historically the 'arch' is armeb, but this causes problems because it is
# generic ('armeb' should really only use instructions present on all ARM
# processors).  Correcting it is difficult, however, because it is written in
# to so many places.
#
# TARGET_ARCH is *wrong* it should be armv5teb or, maybe, thumbv5teb
# however many packages have been modified to recognised 'armeb' inside
# configure scripts, fixing this up to handle arm*eb or thumb*eb is a
# lot of work, so has not yet been done.
#NOTE: do *not* change this is a distro.conf, a lot of work is required
# to get this fixed.
TARGET_ARCH = "armeb"

# The list of valid architectures for thumb or arm on NSLU2.  The arm list is
# derived from the architecture settings known to gcc, the thumb list is then
# derived from that (only the 't' architectures of course).  Note: NSLU2 is
# assumed to imply 'big-endian', though in fact this need not be the case.
NSLU2_ARM_ARCHITECTURES = "armeb armv2b armv2ab armv3b armv3mb armv4b armv4tb armv5b armv5tb armv5eb armv5teb xscaleb"
NSLU2_THUMB_ARCHITECTURES = "thumbeb thumbv4tb thumbv5tb"

# NOTE: this list contains just the things which rootfs_ipk.bbclass does not
# add, rootfs_ipk.bbclass evaluates:
#
# ipkgarchs="all any noarch ${TARGET_ARCH} ${IPKG_ARCHS} ${MACHINE}"
#
# This is a priority ordered list - most desireable architecture at the end, so
# put NSLU2_(ARM_INSTRUCTION_SET)_ARCHITECTURES at the end and, if ARM_INTERWORK
# precede this with the other architectures.
IPKG_ARCHS = "${@(lambda arch_thumb, arch_arm, is_arm, interwork: \
		(interwork and (is_arm and arch_thumb or arch_arm) + ' ' or '') \
		+ (is_arm and arch_arm or arch_thumb)) \
	       (bb.data.getVar('NSLU2_THUMB_ARCHITECTURES', d, 1), \
		bb.data.getVar('NSLU2_ARM_ARCHITECTURES', d, 1), \
		bb.data.getVar('ARM_INSTRUCTION_SET', d, 1) == '', \
		bb.data.getVar('ARM_INTERWORK', d, 1) != '')}"

# The package architecture is 'wrong' - it should be armv5teb or thumbv5teb -
# however this setting is retained for backward compatibility as changing it
# would mean that old systems would not accept new packages!  (armv5teb is not
# in the old system list).
#NOTE: new distros with independent feeds are encouraged to fix this, the
# variable NSLU2_PACKAGE_ARCH is provided for this purpose.
PACKAGE_ARCH = "armeb"
NSLU2_PACKAGE_ARCH = "${@['thumbv5tb', 'armv5teb'][bb.data.getVar('ARM_INSTRUCTION_SET', d, 1) == '']}"

#-------------------------------------------------------------------------------
# Miscellany
#-------------------------------------------------------------------------------
SERIAL_CONSOLE = "115200 ttyS0"
KERNEL_CONSOLE = "ttyS0,115200n8"
USE_VT = "0"

#-------------------------------------------------------------------------------
# Package versions
#-------------------------------------------------------------------------------
CVSDATE_gnu-config ?= "20050713"
CVSDATE_gnu-config-native ?= "20050713"
CVSDATE_ipkg-utils-native ?= "20050713"
CVSDATE_ipkg-link ?= "20050713"

CVS_TARBALL_STASH = "http://sources.nslu2-linux.org/sources/"
INHERIT += "nslu2-mirrors"