6 select ARCH_WANT_FRAME_POINTERS
8 select GENERIC_ATOMIC64
9 select GENERIC_CLOCKEVENTS
11 select GENERIC_IRQ_SHOW
12 select GENERIC_SCHED_CLOCK
13 select MODULES_USE_ELF_RELA
14 select GENERIC_PCI_IOMAP
15 select ARCH_WANT_IPC_PARSE_VERSION
16 select ARCH_WANT_OPTIONAL_GPIOLIB
17 select CLONE_BACKWARDS
20 select HAVE_FUNCTION_TRACER
21 select HAVE_IRQ_TIME_ACCOUNTING
22 select HAVE_PERF_EVENTS
24 Xtensa processors are 32-bit RISC machines designed by Tensilica
25 primarily for embedded systems. These processors are both
26 configurable and extensible. The Linux port to the Xtensa
27 architecture supports all processor configurations and extensions,
28 with reasonable minimum requirements. The Xtensa Linux project has
29 a home page at <http://www.linux-xtensa.org/>.
31 config RWSEM_XCHGADD_ALGORITHM
34 config GENERIC_HWEIGHT
37 config ARCH_HAS_ILOG2_U32
40 config ARCH_HAS_ILOG2_U64
51 source "kernel/Kconfig.freezer"
53 config LOCKDEP_SUPPORT
56 config STACKTRACE_SUPPORT
59 config TRACE_IRQFLAGS_SUPPORT
65 config VARIANT_IRQ_SWITCH
71 menu "Processor type and features"
74 prompt "Xtensa Processor Configuration"
75 default XTENSA_VARIANT_FSF
77 config XTENSA_VARIANT_FSF
78 bool "fsf - default (not generic) configuration"
81 config XTENSA_VARIANT_DC232B
82 bool "dc232b - Diamond 232L Standard Core Rev.B (LE)"
85 This variant refers to Tensilica's Diamond 232L Standard core Rev.B (LE).
87 config XTENSA_VARIANT_DC233C
88 bool "dc233c - Diamond 233L Standard Core Rev.C (LE)"
91 This variant refers to Tensilica's Diamond 233L Standard core Rev.C (LE).
93 config XTENSA_VARIANT_S6000
94 bool "s6000 - Stretch software configurable processor"
95 select VARIANT_IRQ_SWITCH
96 select ARCH_REQUIRE_GPIOLIB
97 select XTENSA_CALIBRATE_CCOUNT
100 config XTENSA_UNALIGNED_USER
101 bool "Unaligned memory access in use space"
103 The Xtensa architecture currently does not handle unaligned
104 memory accesses in hardware but through an exception handler.
105 Per default, unaligned memory accesses are disabled in user space.
107 Say Y here to enable unaligned memory access in user space.
109 source "kernel/Kconfig.preempt"
112 bool "System Supports SMP (MX)"
113 depends on MAY_HAVE_SMP
116 This option is use to indicate that the system-on-a-chip (SOC)
117 supports Multiprocessing. Multiprocessor support implemented above
118 the CPU core definition and currently needs to be selected manually.
120 Multiprocessor support in implemented with external cache and
121 interrupt controlers.
123 The MX interrupt distributer adds Interprocessor Interrupts
124 and causes the IRQ numbers to be increased by 4 for devices
125 like the open cores ethernet driver and the serial interface.
127 You still have to select "Enable SMP" to enable SMP on this SOC.
130 bool "Enable Symmetric multi-processing support"
132 select USE_GENERIC_SMP_HELPERS
133 select GENERIC_SMP_IDLE_THREAD
135 Enabled SMP Software; allows more than one CPU/CORE
136 to be activated during startup.
140 int "Maximum number of CPUs (2-32)"
145 bool "Enable CPU hotplug support"
148 Say Y here to allow turning CPUs off and on. CPUs can be
149 controlled through /sys/devices/system/cpu.
151 Say N if you want to disable CPU hotplug.
153 config MATH_EMULATION
154 bool "Math emulation"
156 Can we use information of configuration file?
158 config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
159 bool "Initialize Xtensa MMU inside the Linux kernel code"
162 Earlier version initialized the MMU in the exception vector
163 before jumping to _startup in head.S and had an advantage that
164 it was possible to place a software breakpoint at 'reset' and
165 then enter your normal kernel breakpoints once the MMU was mapped
166 to the kernel mappings (0XC0000000).
168 This unfortunately doesn't work for U-Boot and likley also wont
169 work for using KEXEC to have a hot kernel ready for doing a
172 So now the MMU is initialized in head.S but it's necessary to
173 use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup.
174 xt-gdb can't place a Software Breakpoint in the 0XD region prior
175 to mapping the MMU and after mapping even if the area of low memory
176 was mapped gdb wouldn't remove the breakpoint on hitting it as the
177 PC wouldn't match. Since Hardware Breakpoints are recommended for
178 Linux configurations it seems reasonable to just assume they exist
179 and leave this older mechanism for unfortunate souls that choose
180 not to follow Tensilica's recommendation.
182 Selecting this will cause U-Boot to set the KERNEL Load and Entry
183 address at 0x00003000 instead of the mapped std of 0xD0003000.
189 config XTENSA_CALIBRATE_CCOUNT
192 On some platforms (XT2000, for example), the CPU clock rate can
193 vary. The frequency can be determined, however, by measuring
194 against a well known, fixed frequency, such as an UART oscillator.
196 config SERIAL_CONSOLE
205 Find out whether you have a PCI motherboard. PCI is the name of a
206 bus system, i.e. the way the CPU talks to the other stuff inside
207 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
208 VESA. If you have PCI, say Y, otherwise N.
210 source "drivers/pci/Kconfig"
214 menu "Platform options"
217 prompt "Xtensa System Type"
218 default XTENSA_PLATFORM_ISS
220 config XTENSA_PLATFORM_ISS
223 select XTENSA_CALIBRATE_CCOUNT
224 select SERIAL_CONSOLE
226 ISS is an acronym for Tensilica's Instruction Set Simulator.
228 config XTENSA_PLATFORM_XT2000
231 XT2000 is the name of Tensilica's feature-rich emulation platform.
232 This hardware is capable of running a full Linux distribution.
234 config XTENSA_PLATFORM_S6105
236 select SERIAL_CONSOLE
239 config XTENSA_PLATFORM_XTFPGA
241 select SERIAL_CONSOLE
243 select XTENSA_CALIBRATE_CCOUNT
245 XTFPGA is the name of Tensilica board family (LX60, LX110, LX200, ML605).
246 This hardware is capable of running a full Linux distribution.
251 config XTENSA_CPU_CLOCK
252 int "CPU clock rate [MHz]"
253 depends on !XTENSA_CALIBRATE_CCOUNT
256 config GENERIC_CALIBRATE_DELAY
257 bool "Auto calibration of the BogoMIPS value"
259 The BogoMIPS value can easily be derived from the CPU frequency.
262 bool "Default bootloader kernel arguments"
265 string "Initial kernel command string"
266 depends on CMDLINE_BOOL
267 default "console=ttyS0,38400 root=/dev/ram"
269 On some architectures (EBSA110 and CATS), there is currently no way
270 for the boot loader to pass arguments to the kernel. For these
271 architectures, you should supply some command-line options at build
272 time by entering them here. As a minimum, you should specify the
273 memory size and the root device (e.g., mem=64M root=/dev/nfs).
276 bool "Flattened Device Tree support"
278 select OF_EARLY_FLATTREE
280 Include support for flattened device tree machine descriptions.
283 string "DTB to build into the kernel image"
286 config BLK_DEV_SIMDISK
287 tristate "Host file-based simulated block device support"
289 depends on XTENSA_PLATFORM_ISS
291 Create block devices that map to files in the host file system.
292 Device binding to host file may be changed at runtime via proc
293 interface provided the device is not in use.
295 config BLK_DEV_SIMDISK_COUNT
296 int "Number of host file-based simulated block devices"
298 depends on BLK_DEV_SIMDISK
301 This is the default minimal number of created block devices.
302 Kernel/module parameter 'simdisk_count' may be used to change this
303 value at runtime. More file names (but no more than 10) may be
304 specified as parameters, simdisk_count grows accordingly.
306 config SIMDISK0_FILENAME
307 string "Host filename for the first simulated device"
308 depends on BLK_DEV_SIMDISK = y
311 Attach a first simdisk to a host file. Conventionally, this file
312 contains a root file system.
314 config SIMDISK1_FILENAME
315 string "Host filename for the second simulated device"
316 depends on BLK_DEV_SIMDISK = y && BLK_DEV_SIMDISK_COUNT != 1
319 Another simulated disk in a host file for a buildroot-independent
324 source "drivers/pcmcia/Kconfig"
326 source "drivers/pci/hotplug/Kconfig"
330 menu "Executable file formats"
332 source "fs/Kconfig.binfmt"
338 source "drivers/Kconfig"
342 source "arch/xtensa/Kconfig.debug"
344 source "security/Kconfig"
346 source "crypto/Kconfig"