config ZONE_DMA
def_bool y
config XTENSA
def_bool y
select ARCH_WANT_FRAME_POINTERS
select ARCH_WANT_IPC_PARSE_VERSION
select ARCH_WANT_OPTIONAL_GPIOLIB
select BUILDTIME_EXTABLE_SORT
select CLONE_BACKWARDS
select COMMON_CLK
select GENERIC_ATOMIC64
select GENERIC_CLOCKEVENTS
select GENERIC_IRQ_SHOW
select GENERIC_PCI_IOMAP
select GENERIC_SCHED_CLOCK
select HAVE_FUNCTION_TRACER
select HAVE_IRQ_TIME_ACCOUNTING
select HAVE_OPROFILE
select HAVE_PERF_EVENTS
select IRQ_DOMAIN
select MODULES_USE_ELF_RELA
select VIRT_TO_BUS
help
Xtensa processors are 32-bit RISC machines designed by Tensilica
primarily for embedded systems. These processors are both
configurable and extensible. The Linux port to the Xtensa
architecture supports all processor configurations and extensions,
with reasonable minimum requirements. The Xtensa Linux project has
a home page at <http://www.linux-xtensa.org/>.
config RWSEM_XCHGADD_ALGORITHM
def_bool y
config GENERIC_HWEIGHT
def_bool y
config ARCH_HAS_ILOG2_U32
def_bool n
config ARCH_HAS_ILOG2_U64
def_bool n
config NO_IOPORT_MAP
def_bool n
config HZ
int
default 100
source "init/Kconfig"
source "kernel/Kconfig.freezer"
config LOCKDEP_SUPPORT
def_bool y
config STACKTRACE_SUPPORT
def_bool y
config TRACE_IRQFLAGS_SUPPORT
def_bool y
config MMU
bool
default n if !XTENSA_VARIANT_CUSTOM
default XTENSA_VARIANT_MMU if XTENSA_VARIANT_CUSTOM
config VARIANT_IRQ_SWITCH
def_bool n
config HAVE_XTENSA_GPIO32
def_bool n
config MAY_HAVE_SMP
def_bool n
menu "Processor type and features"
choice
prompt "Xtensa Processor Configuration"
default XTENSA_VARIANT_FSF
config XTENSA_VARIANT_FSF
bool "fsf - default (not generic) configuration"
select MMU
config XTENSA_VARIANT_DC232B
bool "dc232b - Diamond 232L Standard Core Rev.B (LE)"
select MMU
select HAVE_XTENSA_GPIO32
help
This variant refers to Tensilica's Diamond 232L Standard core Rev.B (LE).
config XTENSA_VARIANT_DC233C
bool "dc233c - Diamond 233L Standard Core Rev.C (LE)"
select MMU
select HAVE_XTENSA_GPIO32
help
This variant refers to Tensilica's Diamond 233L Standard core Rev.C (LE).
config XTENSA_VARIANT_CUSTOM
bool "Custom Xtensa processor configuration"
select MAY_HAVE_SMP
select HAVE_XTENSA_GPIO32
help
Select this variant to use a custom Xtensa processor configuration.
You will be prompted for a processor variant CORENAME.
endchoice
config XTENSA_VARIANT_CUSTOM_NAME
string "Xtensa Processor Custom Core Variant Name"
depends on XTENSA_VARIANT_CUSTOM
help
Provide the name of a custom Xtensa processor variant.
This CORENAME selects arch/xtensa/variant/CORENAME.
Dont forget you have to select MMU if you have one.
config XTENSA_VARIANT_NAME
string
default "dc232b" if XTENSA_VARIANT_DC232B
default "dc233c" if XTENSA_VARIANT_DC233C
default "fsf" if XTENSA_VARIANT_FSF
default XTENSA_VARIANT_CUSTOM_NAME if XTENSA_VARIANT_CUSTOM
config XTENSA_VARIANT_MMU
bool "Core variant has a Full MMU (TLB, Pages, Protection, etc)"
depends on XTENSA_VARIANT_CUSTOM
default y
help
Build a Conventional Kernel with full MMU support,
ie: it supports a TLB with auto-loading, page protection.
config XTENSA_UNALIGNED_USER
bool "Unaligned memory access in use space"
help
The Xtensa architecture currently does not handle unaligned
memory accesses in hardware but through an exception handler.
Per default, unaligned memory accesses are disabled in user space.
Say Y here to enable unaligned memory access in user space.
source "kernel/Kconfig.preempt"
config HAVE_SMP
bool "System Supports SMP (MX)"
depends on MAY_HAVE_SMP
select XTENSA_MX
help
This option is use to indicate that the system-on-a-chip (SOC)
supports Multiprocessing. Multiprocessor support implemented above
the CPU core definition and currently needs to be selected manually.
Multiprocessor support in implemented with external cache and
interrupt controlers.
The MX interrupt distributer adds Interprocessor Interrupts
and causes the IRQ numbers to be increased by 4 for devices
like the open cores ethernet driver and the serial interface.
You still have to select "Enable SMP" to enable SMP on this SOC.
config SMP
bool "Enable Symmetric multi-processing support"
depends on HAVE_SMP
select GENERIC_SMP_IDLE_THREAD
help
Enabled SMP Software; allows more than one CPU/CORE
to be activated during startup.
config NR_CPUS
depends on SMP
int "Maximum number of CPUs (2-32)"
range 2 32
default "4"
config HOTPLUG_CPU
bool "Enable CPU hotplug support"
depends on SMP
help
Say Y here to allow turning CPUs off and on. CPUs can be
controlled through /sys/devices/system/cpu.
Say N if you want to disable CPU hotplug.
config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
bool "Initialize Xtensa MMU inside the Linux kernel code"
default y
help
Earlier version initialized the MMU in the exception vector
before jumping to _startup in head.S and had an advantage that
it was possible to place a software breakpoint at 'reset' and
then enter your normal kernel breakpoints once the MMU was mapped
to the kernel mappings (0XC0000000).
This unfortunately doesn't work for U-Boot and likley also wont
work for using KEXEC to have a hot kernel ready for doing a
KDUMP.
So now the MMU is initialized in head.S but it's necessary to
use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup.
xt-gdb can't place a Software Breakpoint in the 0XD region prior
to mapping the MMU and after mapping even if the area of low memory
was mapped gdb wouldn't remove the breakpoint on hitting it as the
PC wouldn't match. Since Hardware Breakpoints are recommended for
Linux configurations it seems reasonable to just assume they exist
and leave this older mechanism for unfortunate souls that choose
not to follow Tensilica's recommendation.
Selecting this will cause U-Boot to set the KERNEL Load and Entry
address at 0x00003000 instead of the mapped std of 0xD0003000.
If in doubt, say Y.
config HIGHMEM
bool "High Memory Support"
depends on MMU
help
Linux can use the full amount of RAM in the system by
default. However, the default MMUv2 setup only maps the
lowermost 128 MB of memory linearly to the areas starting
at 0xd0000000 (cached) and 0xd8000000 (uncached).
When there are more than 128 MB memory in the system not
all of it can be "permanently mapped" by the kernel.
The physical memory that's not permanently mapped is called
"high memory".
If you are compiling a kernel which will never run on a
machine with more than 128 MB total physical RAM, answer
N here.
If unsure, say Y.
config FAST_SYSCALL_XTENSA
bool "Enable fast atomic syscalls"
default n
help
fast_syscall_xtensa is a syscall that can make atomic operations
on UP kernel when processor has no s32c1i support.
This syscall is deprecated. It may have issues when called with
invalid arguments. It is provided only for backwards compatibility.
Only enable it if your userspace software requires it.
If unsure, say N.
config FAST_SYSCALL_SPILL_REGISTERS
bool "Enable spill registers syscall"
default n
help
fast_syscall_spill_registers is a syscall that spills all active
register windows of a calling userspace task onto its stack.
This syscall is deprecated. It may have issues when called with
invalid arguments. It is provided only for backwards compatibility.
Only enable it if your userspace software requires it.
If unsure, say N.
endmenu
config XTENSA_CALIBRATE_CCOUNT
def_bool n
help
On some platforms (XT2000, for example), the CPU clock rate can
vary. The frequency can be determined, however, by measuring
against a well known, fixed frequency, such as an UART oscillator.
config SERIAL_CONSOLE
def_bool n
menu "Bus options"
config PCI
bool "PCI support"
default y
help
Find out whether you have a PCI motherboard. PCI is the name of a
bus system, i.e. the way the CPU talks to the other stuff inside
your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
VESA. If you have PCI, say Y, otherwise N.
source "drivers/pci/Kconfig"
endmenu
menu "Platform options"
choice
prompt "Xtensa System Type"
default XTENSA_PLATFORM_ISS
config XTENSA_PLATFORM_ISS
bool "ISS"
select XTENSA_CALIBRATE_CCOUNT
select SERIAL_CONSOLE
help
ISS is an acronym for Tensilica's Instruction Set Simulator.
config XTENSA_PLATFORM_XT2000
bool "XT2000"
select HAVE_IDE
help
XT2000 is the name of Tensilica's feature-rich emulation platform.
This hardware is capable of running a full Linux distribution.
config XTENSA_PLATFORM_XTFPGA
bool "XTFPGA"
select ETHOC if ETHERNET
select PLATFORM_WANT_DEFAULT_MEM
select SERIAL_CONSOLE
select XTENSA_CALIBRATE_CCOUNT
help
XTFPGA is the name of Tensilica board family (LX60, LX110, LX200, ML605).
This hardware is capable of running a full Linux distribution.
endchoice
config XTENSA_CPU_CLOCK
int "CPU clock rate [MHz]"
depends on !XTENSA_CALIBRATE_CCOUNT
default 16
config GENERIC_CALIBRATE_DELAY
bool "Auto calibration of the BogoMIPS value"
help
The BogoMIPS value can easily be derived from the CPU frequency.
config CMDLINE_BOOL
bool "Default bootloader kernel arguments"
config CMDLINE
string "Initial kernel command string"
depends on CMDLINE_BOOL
default "console=ttyS0,38400 root=/dev/ram"
help
On some architectures (EBSA110 and CATS), there is currently no way
for the boot loader to pass arguments to the kernel. For these
architectures, you should supply some command-line options at build
time by entering them here. As a minimum, you should specify the
memory size and the root device (e.g., mem=64M root=/dev/nfs).
config USE_OF
bool "Flattened Device Tree support"
select OF
select OF_EARLY_FLATTREE
help
Include support for flattened device tree machine descriptions.
config BUILTIN_DTB
string "DTB to build into the kernel image"
depends on OF
config BLK_DEV_SIMDISK
tristate "Host file-based simulated block device support"
default n
depends on XTENSA_PLATFORM_ISS && BLOCK
help
Create block devices that map to files in the host file system.
Device binding to host file may be changed at runtime via proc
interface provided the device is not in use.
config BLK_DEV_SIMDISK_COUNT
int "Number of host file-based simulated block devices"
range 1 10
depends on BLK_DEV_SIMDISK
default 2
help
This is the default minimal number of created block devices.
Kernel/module parameter 'simdisk_count' may be used to change this
value at runtime. More file names (but no more than 10) may be
specified as parameters, simdisk_count grows accordingly.
config SIMDISK0_FILENAME
string "Host filename for the first simulated device"
depends on BLK_DEV_SIMDISK = y
default ""
help
Attach a first simdisk to a host file. Conventionally, this file
contains a root file system.
config SIMDISK1_FILENAME
string "Host filename for the second simulated device"
depends on BLK_DEV_SIMDISK = y && BLK_DEV_SIMDISK_COUNT != 1
default ""
help
Another simulated disk in a host file for a buildroot-independent
storage.
source "mm/Kconfig"
source "drivers/pcmcia/Kconfig"
source "drivers/pci/hotplug/Kconfig"
config PLATFORM_WANT_DEFAULT_MEM
def_bool n
config DEFAULT_MEM_START
hex "Physical address of the default memory area start"
depends on PLATFORM_WANT_DEFAULT_MEM
default 0x00000000 if MMU
default 0x40000000 if !MMU
help
This is a fallback start address of the default memory area, it is
used when no physical memory size is passed through DTB or through
boot parameter from bootloader.
In noMMU configuration the following parameters are derived from it:
- kernel load address;
- kernel entry point address;
- relocatable vectors base address;
- uBoot load address;
- TASK_SIZE.
If unsure, leave the default value here.
config DEFAULT_MEM_SIZE
hex "Maximal size of the default memory area"
depends on PLATFORM_WANT_DEFAULT_MEM
default 0x04000000
help
This is a fallback size of the default memory area, it is used when
no physical memory size is passed through DTB or through boot
parameter from bootloader.
It's also used for TASK_SIZE calculation in noMMU configuration.
If unsure, leave the default value here.
endmenu
menu "Executable file formats"
source "fs/Kconfig.binfmt"
endmenu
menu "Power management options"
source "kernel/power/Kconfig"
endmenu
source "net/Kconfig"
source "drivers/Kconfig"
source "fs/Kconfig"
source "arch/xtensa/Kconfig.debug"
source "security/Kconfig"
source "crypto/Kconfig"
source "lib/Kconfig"
