diff mbox

[dpdk-dev,v4,01/14] Add compiling definations for IBM Power architecture

Message ID 1416926626-7942-2-git-send-email-chaozhu@linux.vnet.ibm.com (mailing list archive)
State Superseded, archived
Headers show

Commit Message

Chao Zhu Nov. 25, 2014, 2:43 p.m. UTC
To make DPDK run on IBM Power architecture, configuration files for
Power architecuture are added. Also, the compiling related .mk files are
added.

Signed-off-by: Chao Zhu <chaozhu@linux.vnet.ibm.com>
---
 config/common_linuxapp_powerpc              |  394 +++++++++++++++++++++++++++
 config/defconfig_ppc_64-power8-linuxapp-gcc |   40 +++
 mk/arch/ppc_64/rte.vars.mk                  |   39 +++
 mk/machine/power8/rte.vars.mk               |   57 ++++
 4 files changed, 530 insertions(+), 0 deletions(-)
 create mode 100644 config/common_linuxapp_powerpc
 create mode 100644 config/defconfig_ppc_64-power8-linuxapp-gcc
 create mode 100644 mk/arch/ppc_64/rte.vars.mk
 create mode 100644 mk/machine/power8/rte.vars.mk
diff mbox

Patch

diff --git a/config/common_linuxapp_powerpc b/config/common_linuxapp_powerpc
new file mode 100644
index 0000000..d230a0b
--- /dev/null
+++ b/config/common_linuxapp_powerpc
@@ -0,0 +1,394 @@ 
+#   BSD LICENSE
+#
+#   Copyright (C) IBM Corporation 2014.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of IBM Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+#
+# define executive environment
+#
+# CONFIG_RTE_EXEC_ENV can be linuxapp, baremetal, bsdapp
+#
+CONFIG_RTE_EXEC_ENV="linuxapp"
+CONFIG_RTE_EXEC_ENV_LINUXAPP=y
+
+#
+# Use intrinsics or assembly code for key routines
+#
+CONFIG_RTE_FORCE_INTRINSICS=n
+
+#
+# Compile to share library
+#
+CONFIG_RTE_BUILD_SHARED_LIB=n
+
+#
+# Combine to one single library
+#
+CONFIG_RTE_BUILD_COMBINE_LIBS=n
+CONFIG_RTE_LIBNAME="powerpc_dpdk"
+
+#
+# Compile libc directory
+#
+CONFIG_RTE_LIBC=n
+
+#
+# Compile newlib as libc from source
+#
+CONFIG_RTE_LIBC_NEWLIB_SRC=n
+
+#
+# Use binary newlib
+#
+CONFIG_RTE_LIBC_NEWLIB_BIN=n
+
+#
+# Use binary newlib
+#
+CONFIG_RTE_LIBC_NETINCS=n
+
+#
+# Compile libgloss (newlib-stubs)
+#
+CONFIG_RTE_LIBGLOSS=n
+
+#
+# Compile Environment Abstraction Layer
+# Note: Power8 has 96 cores, so increase CONFIG_RTE_MAX_LCORE from 64 to 128
+#
+CONFIG_RTE_LIBRTE_EAL=y
+CONFIG_RTE_MAX_LCORE=128
+CONFIG_RTE_MAX_NUMA_NODES=8
+CONFIG_RTE_MAX_MEMSEG=256
+CONFIG_RTE_MAX_MEMZONE=2560
+CONFIG_RTE_MAX_TAILQ=32
+CONFIG_RTE_LOG_LEVEL=8
+CONFIG_RTE_LOG_HISTORY=256
+CONFIG_RTE_LIBEAL_USE_HPET=n
+CONFIG_RTE_EAL_ALLOW_INV_SOCKET_ID=n
+CONFIG_RTE_EAL_ALWAYS_PANIC_ON_ERROR=n
+CONFIG_RTE_EAL_IGB_UIO=y
+CONFIG_RTE_EAL_VFIO=y
+
+#
+# Special configurations in PCI Config Space for high performance
+#
+CONFIG_RTE_PCI_CONFIG=n
+CONFIG_RTE_PCI_EXTENDED_TAG=""
+CONFIG_RTE_PCI_MAX_READ_REQUEST_SIZE=0
+
+#
+# Compile Environment Abstraction Layer for linux
+#
+CONFIG_RTE_LIBRTE_EAL_LINUXAPP=y
+
+#
+# Compile Environment Abstraction Layer for Bare metal
+#
+CONFIG_RTE_LIBRTE_EAL_BAREMETAL=n
+
+#
+# Compile Environment Abstraction Layer to support Vmware TSC map
+# Note: Power doesn't have this support
+#
+CONFIG_RTE_LIBRTE_EAL_VMWARE_TSC_MAP_SUPPORT=n
+
+#
+# Compile the argument parser library
+#
+CONFIG_RTE_LIBRTE_KVARGS=y
+
+#
+# Compile generic ethernet library
+#
+CONFIG_RTE_LIBRTE_ETHER=y
+CONFIG_RTE_LIBRTE_ETHDEV_DEBUG=n
+CONFIG_RTE_MAX_ETHPORTS=32
+CONFIG_RTE_LIBRTE_IEEE1588=n
+CONFIG_RTE_ETHDEV_QUEUE_STAT_CNTRS=16
+
+#
+# Support NIC bypass logic
+#
+CONFIG_RTE_NIC_BYPASS=n
+
+#
+# Note: Initially, all of the PMD drivers compilation are turned off on Power
+# Will turn on them only after the successful testing on Power
+#
+
+#
+# Compile burst-oriented IGB & EM PMD drivers
+#
+CONFIG_RTE_LIBRTE_EM_PMD=n
+CONFIG_RTE_LIBRTE_IGB_PMD=n
+CONFIG_RTE_LIBRTE_E1000_DEBUG_INIT=n
+CONFIG_RTE_LIBRTE_E1000_DEBUG_RX=n
+CONFIG_RTE_LIBRTE_E1000_DEBUG_TX=n
+CONFIG_RTE_LIBRTE_E1000_DEBUG_TX_FREE=n
+CONFIG_RTE_LIBRTE_E1000_DEBUG_DRIVER=n
+CONFIG_RTE_LIBRTE_E1000_PF_DISABLE_STRIP_CRC=n
+
+#
+# Compile burst-oriented IXGBE PMD driver
+#
+CONFIG_RTE_LIBRTE_IXGBE_PMD=n
+CONFIG_RTE_LIBRTE_IXGBE_DEBUG_INIT=n
+CONFIG_RTE_LIBRTE_IXGBE_DEBUG_RX=n
+CONFIG_RTE_LIBRTE_IXGBE_DEBUG_TX=n
+CONFIG_RTE_LIBRTE_IXGBE_DEBUG_TX_FREE=n
+CONFIG_RTE_LIBRTE_IXGBE_DEBUG_DRIVER=n
+CONFIG_RTE_LIBRTE_IXGBE_PF_DISABLE_STRIP_CRC=n
+CONFIG_RTE_LIBRTE_IXGBE_RX_ALLOW_BULK_ALLOC=y
+CONFIG_RTE_IXGBE_INC_VECTOR=y
+CONFIG_RTE_IXGBE_RX_OLFLAGS_ENABLE=y
+
+#
+# Compile burst-oriented I40E PMD driver
+#
+CONFIG_RTE_LIBRTE_I40E_PMD=n
+CONFIG_RTE_LIBRTE_I40E_DEBUG_INIT=n
+CONFIG_RTE_LIBRTE_I40E_DEBUG_RX=n
+CONFIG_RTE_LIBRTE_I40E_DEBUG_TX=n
+CONFIG_RTE_LIBRTE_I40E_DEBUG_TX_FREE=n
+CONFIG_RTE_LIBRTE_I40E_DEBUG_DRIVER=n
+CONFIG_RTE_LIBRTE_I40E_RX_ALLOW_BULK_ALLOC=y
+CONFIG_RTE_LIBRTE_I40E_16BYTE_RX_DESC=n
+CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_VF=4
+CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_VM=4
+# interval up to 8160 us, aligned to 2 (or default value)
+CONFIG_RTE_LIBRTE_I40E_ITR_INTERVAL=-1
+
+#
+# Compile burst-oriented VIRTIO PMD driver
+#
+CONFIG_RTE_LIBRTE_VIRTIO_PMD=n
+CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_INIT=n
+CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_RX=n
+CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_TX=n
+CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_DRIVER=n
+CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_DUMP=n
+
+#
+# Compile burst-oriented VMXNET3 PMD driver
+#
+CONFIG_RTE_LIBRTE_VMXNET3_PMD=n
+CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_INIT=n
+CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_RX=n
+CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_TX=n
+CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_TX_FREE=n
+CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_DRIVER=n
+
+#
+# Compile example software rings based PMD
+#
+CONFIG_RTE_LIBRTE_PMD_RING=y
+CONFIG_RTE_PMD_RING_MAX_RX_RINGS=16
+CONFIG_RTE_PMD_RING_MAX_TX_RINGS=16
+
+#
+# Compile software PMD backed by PCAP files
+#
+CONFIG_RTE_LIBRTE_PMD_PCAP=n
+
+#
+# Compile link bonding PMD library
+#
+CONFIG_RTE_LIBRTE_PMD_BOND=n
+
+#
+# Compile Xen PMD
+#
+CONFIG_RTE_LIBRTE_PMD_XENVIRT=n
+
+#
+# Do prefetch of packet data within PMD driver receive function
+#
+CONFIG_RTE_PMD_PACKET_PREFETCH=y
+
+#
+# Compile librte_ring
+#
+CONFIG_RTE_LIBRTE_RING=y
+CONFIG_RTE_LIBRTE_RING_DEBUG=n
+CONFIG_RTE_RING_SPLIT_PROD_CONS=n
+
+#
+# Compile librte_mempool
+#
+CONFIG_RTE_LIBRTE_MEMPOOL=y
+CONFIG_RTE_MEMPOOL_CACHE_MAX_SIZE=512
+CONFIG_RTE_LIBRTE_MEMPOOL_DEBUG=n
+
+#
+# Compile librte_mbuf
+#
+CONFIG_RTE_LIBRTE_MBUF=y
+CONFIG_RTE_LIBRTE_MBUF_DEBUG=n
+CONFIG_RTE_MBUF_REFCNT=y
+CONFIG_RTE_MBUF_REFCNT_ATOMIC=y
+CONFIG_RTE_PKTMBUF_HEADROOM=128
+
+#
+# Compile librte_timer
+#
+CONFIG_RTE_LIBRTE_TIMER=y
+CONFIG_RTE_LIBRTE_TIMER_DEBUG=n
+
+#
+# Compile librte_malloc
+#
+CONFIG_RTE_LIBRTE_MALLOC=y
+CONFIG_RTE_LIBRTE_MALLOC_DEBUG=n
+CONFIG_RTE_MALLOC_MEMZONE_SIZE=11M
+
+#
+# Compile librte_cfgfile
+#
+CONFIG_RTE_LIBRTE_CFGFILE=y
+
+#
+# Compile librte_cmdline
+#
+CONFIG_RTE_LIBRTE_CMDLINE=y
+CONFIG_RTE_LIBRTE_CMDLINE_DEBUG=n
+
+#
+# Compile librte_hash
+#
+CONFIG_RTE_LIBRTE_HASH=y
+CONFIG_RTE_LIBRTE_HASH_DEBUG=n
+
+#
+# Compile librte_lpm
+#
+CONFIG_RTE_LIBRTE_LPM=n
+CONFIG_RTE_LIBRTE_LPM_DEBUG=n
+
+#
+# Compile librte_acl
+#
+CONFIG_RTE_LIBRTE_ACL=n
+CONFIG_RTE_LIBRTE_ACL_DEBUG=n
+CONFIG_RTE_LIBRTE_ACL_STANDALONE=n
+
+#
+# Compile librte_power
+#
+CONFIG_RTE_LIBRTE_POWER=y
+CONFIG_RTE_LIBRTE_POWER_DEBUG=n
+CONFIG_RTE_MAX_LCORE_FREQS=64
+
+#
+# Compile librte_net
+#
+CONFIG_RTE_LIBRTE_NET=y
+
+#
+# Compile librte_ip_frag
+#
+CONFIG_RTE_LIBRTE_IP_FRAG=y
+CONFIG_RTE_LIBRTE_IP_FRAG_DEBUG=n
+CONFIG_RTE_LIBRTE_IP_FRAG_MAX_FRAG=4
+CONFIG_RTE_LIBRTE_IP_FRAG_TBL_STAT=n
+
+#
+# Compile librte_meter
+#
+CONFIG_RTE_LIBRTE_METER=y
+
+#
+# Compile librte_sched
+#
+CONFIG_RTE_LIBRTE_SCHED=n
+CONFIG_RTE_SCHED_RED=n
+CONFIG_RTE_SCHED_COLLECT_STATS=n
+CONFIG_RTE_SCHED_SUBPORT_TC_OV=n
+CONFIG_RTE_SCHED_PORT_N_GRINDERS=8
+
+#
+# Compile the distributor library
+#
+CONFIG_RTE_LIBRTE_DISTRIBUTOR=y
+
+#
+# Compile librte_port
+#
+CONFIG_RTE_LIBRTE_PORT=n
+
+#
+# Compile librte_table
+#
+CONFIG_RTE_LIBRTE_TABLE=n
+
+#
+# Compile librte_pipeline
+#
+CONFIG_RTE_LIBRTE_PIPELINE=n
+
+#
+# Compile librte_kni
+#
+CONFIG_RTE_LIBRTE_KNI=y
+CONFIG_RTE_KNI_KO_DEBUG=n
+CONFIG_RTE_KNI_VHOST=n
+CONFIG_RTE_KNI_VHOST_MAX_CACHE_SIZE=1024
+CONFIG_RTE_KNI_VHOST_VNET_HDR_EN=n
+CONFIG_RTE_KNI_VHOST_DEBUG_RX=n
+CONFIG_RTE_KNI_VHOST_DEBUG_TX=n
+
+#
+# Compile vhost library
+# fuse-devel is needed to run vhost.
+# fuse-devel enables user space char driver development
+#
+CONFIG_RTE_LIBRTE_VHOST=n
+CONFIG_RTE_LIBRTE_VHOST_DEBUG=n
+
+#
+#Compile Xen domain0 support
+#
+CONFIG_RTE_LIBRTE_XEN_DOM0=n
+
+#
+# Enable warning directives
+#
+CONFIG_RTE_INSECURE_FUNCTION_WARNING=n
+
+#
+# Compile the test application
+#
+CONFIG_RTE_APP_TEST=y
+
+#
+# Compile the PMD test application
+#
+CONFIG_RTE_TEST_PMD=n
+CONFIG_RTE_TEST_PMD_RECORD_CORE_CYCLES=n
+CONFIG_RTE_TEST_PMD_RECORD_BURST_STATS=n
diff --git a/config/defconfig_ppc_64-power8-linuxapp-gcc b/config/defconfig_ppc_64-power8-linuxapp-gcc
new file mode 100644
index 0000000..97d72ff
--- /dev/null
+++ b/config/defconfig_ppc_64-power8-linuxapp-gcc
@@ -0,0 +1,40 @@ 
+#   BSD LICENSE
+#
+#   Copyright (C) IBM Corporation 2014.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of IBM Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "common_linuxapp_powerpc"
+
+CONFIG_RTE_MACHINE="power8"
+
+CONFIG_RTE_ARCH="ppc_64"
+CONFIG_RTE_ARCH_PPC_64=y
+
+CONFIG_RTE_TOOLCHAIN="gcc"
+CONFIG_RTE_TOOLCHAIN_GCC=y
+
diff --git a/mk/arch/ppc_64/rte.vars.mk b/mk/arch/ppc_64/rte.vars.mk
new file mode 100644
index 0000000..363fcd1
--- /dev/null
+++ b/mk/arch/ppc_64/rte.vars.mk
@@ -0,0 +1,39 @@ 
+#   BSD LICENSE
+#
+#   Copyright (C) IBM Corporation 2014.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of IBM Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+ARCH  ?= powerpc
+CROSS ?=
+
+CPU_CFLAGS  ?= -m64
+CPU_LDFLAGS ?=
+CPU_ASFLAGS ?= -felf64
+
+export ARCH CROSS CPU_CFLAGS CPU_LDFLAGS CPU_ASFLAGS
diff --git a/mk/machine/power8/rte.vars.mk b/mk/machine/power8/rte.vars.mk
new file mode 100644
index 0000000..bae5e98
--- /dev/null
+++ b/mk/machine/power8/rte.vars.mk
@@ -0,0 +1,57 @@ 
+#   BSD LICENSE
+#
+#   Copyright (C) IBM Corporation 2014.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of IBM Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#
+# machine:
+#
+#   - can define ARCH variable (overriden by cmdline value)
+#   - can define CROSS variable (overriden by cmdline value)
+#   - define MACHINE_CFLAGS variable (overriden by cmdline value)
+#   - define MACHINE_LDFLAGS variable (overriden by cmdline value)
+#   - define MACHINE_ASFLAGS variable (overriden by cmdline value)
+#   - can define CPU_CFLAGS variable (overriden by cmdline value) that
+#     overrides the one defined in arch.
+#   - can define CPU_LDFLAGS variable (overriden by cmdline value) that
+#     overrides the one defined in arch.
+#   - can define CPU_ASFLAGS variable (overriden by cmdline value) that
+#     overrides the one defined in arch.
+#   - may override any previously defined variable
+#
+
+# ARCH =
+# CROSS =
+# MACHINE_CFLAGS =
+# MACHINE_LDFLAGS =
+# MACHINE_ASFLAGS =
+# CPU_CFLAGS =
+# CPU_LDFLAGS =
+# CPU_ASFLAGS =
+
+MACHINE_CFLAGS =