1: register r0 <---- 0
register r1 <---- machine ID (it should exist in arch/arm/tools/mach-types and kernel will check it!)
2: parameters structure name ATAG
We copy the source code from versatile board:
$> cp -rf arch/arm/mach-versatile arch/arm/mach-neo $> cp -rf arch/arm/plat-versatile arch/arm/plat-neo
We add our machine type in arch/arm/tools/mach-types:
$> vi arch/arm/tools/mach-types ---------------------------------------------------------------------------- neo MACH_NEO NEO 387 ----------------------------------------------------------------------------
We modify arch/arm/Kconfig to add ARCH_NEO & PLAT_NEO and source them:
$> vi arch/arm/Kconfig
--------------------------
.................
config ARCH_NEO
bool "NEO development board"
select ARM_AMBA
select ARM_VIC
select CLKDEV_LOOKUP
select HAVE_MACH_CLKDEV
select ICST
select GENERIC_CLOCKEVENTS
select ARCH_WANT_OPTIONAL_GPIOLIB
select PLAT_NEO
select PLAT_VERSATILE_CLCD
select PLAT_VERSATILE_FPGA_IRQ
select ARM_TIMER_SP804
help
This enables support for NEO development board.
...................
config PLAT_NEO
bool
..................
source "arch/arm/mach-neo/Kconfig"
source "arch/arm/plat-neo/Kconfig"
..................
--------------------------
We modify arch/arm/Makefile to refer to mach-neo & plat-neo if we used:
$> vi arch/arm/Makefile ------------------------- ................... machine-$(CONFIG_ARCH_NEO) := neo ................... plat-$(CONFIG_PLAT_NEO) := neo .................. -------------------------
We also need to modify arch/arm/mach-neo/Kconfig:
$> vi arch/arm/mach-neo/Kconfig
-------------------------
menu "NEO development board platform type"
depends on ARCH_NEO
config ARCH_VERSATILE_PB
bool "Support NEO Platform Baseboard for ARM926EJ-S"
select CPU_ARM926T
select MIGHT_HAVE_PCI
default y
help
Include support for the ARM(R) Versatile Platform Baseboard
for the ARM926EJ-S.
config MACH_VERSATILE_AB
bool "Support NEO Application Baseboard for ARM926EJ-S"
select CPU_ARM926T
help
Include support for the ARM(R) Versatile Application Baseboard
for the ARM926EJ-S.
config MACH_VERSATILE_DT
bool "Support NEO platform from device tree"
select USE_OF
select CPU_ARM926T
help
Include support for the ARM(R) Versatile/PB platform,
using the device tree for discovery
endmenu
-------------------------
Modify arch/arm/plat-neo/Kconfig too:
$> vi arch/arm/plat-neo/Kconfig
-------------------------
if PLAT_NEO
config PLAT_VERSATILE_CLCD
bool
config PLAT_VERSATILE_FPGA_IRQ
bool
config PLAT_VERSATILE_LEDS
def_bool y if LEDS_CLASS
depends on ARCH_REALVIEW || ARCH_NEO
config PLAT_VERSATILE_SCHED_CLOCK
def_bool y
endif
-------------------------
Now, we can create new defconfig:
$> make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabi- versatile_defconfig
$> make ARCH=arm menuconfig
-------------------------
System Type --->
ARM system type (ARM Ltd. Versatile family) --->
(X) NEO development board
NEO platform type --->
[*] Support NEO platform from device tree
Kernel Features --->
[*] Use the ARM EABI to compile the kernel
[*] Allow old ABI binaries to run with this kernel (EXPERIMENTAL) (NEW)
-------------------------
$> cp .config arch/arm/configs/neo_defconfig
We can make zImage by using our new defconfig:
$> make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabi- neo_defconfig $> make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabi- zImage $> make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabi- versatile-pb.dtb
Emulator:
$> qemu-system-arm -M versatilepb -dtb ./versatile-pb.dtb -kernel zImage -initrd rootfs.img -serial stdio -append "root=/dev/ram rdinit=/sbin/init console=ttyAMA0"
PS:
1 You can install QEMU in UBUNTU by:
1 You can install QEMU in UBUNTU by:
$> sudo apt-get install qemu qmeu-kvm-extras
2 "CROSS_COMPILE=arm-none-linux-gnueabi-" depends on your toolchain.
4 You can see versatile-pb.dts in path arch/arm/boot/dts
5 Because we use "-M versatilepb" to emulate, the machine type in arch/arm/tools/mach-types should be 387.
5 Because we use "-M versatilepb" to emulate, the machine type in arch/arm/tools/mach-types should be 387.
