10 select GENERIC_ATOMIC64
11 select HAVE_GENERIC_HARDIRQS
13 select GENERIC_IRQ_SHOW
14 select GENERIC_CPU_DEVICES
15 select MODULES_USE_ELF_RELA
16 select GENERIC_PCI_IOMAP
17 select ARCH_WANT_IPC_PARSE_VERSION
18 select ARCH_WANT_OPTIONAL_GPIOLIB
19 select CLONE_BACKWARDS
23 Xtensa processors are 32-bit RISC machines designed by Tensilica
24 primarily for embedded systems. These processors are both
25 configurable and extensible. The Linux port to the Xtensa
26 architecture supports all processor configurations and extensions,
27 with reasonable minimum requirements. The Xtensa Linux project has
28 a home page at <http://www.linux-xtensa.org/>.
30 config RWSEM_XCHGADD_ALGORITHM
33 config GENERIC_HWEIGHT
39 config ARCH_HAS_ILOG2_U32
42 config ARCH_HAS_ILOG2_U64
53 source "kernel/Kconfig.freezer"
58 config VARIANT_IRQ_SWITCH
61 menu "Processor type and features"
64 prompt "Xtensa Processor Configuration"
65 default XTENSA_VARIANT_FSF
67 config XTENSA_VARIANT_FSF
68 bool "fsf - default (not generic) configuration"
71 config XTENSA_VARIANT_DC232B
72 bool "dc232b - Diamond 232L Standard Core Rev.B (LE)"
75 This variant refers to Tensilica's Diamond 232L Standard core Rev.B (LE).
77 config XTENSA_VARIANT_DC233C
78 bool "dc233c - Diamond 233L Standard Core Rev.C (LE)"
81 This variant refers to Tensilica's Diamond 233L Standard core Rev.C (LE).
83 config XTENSA_VARIANT_S6000
84 bool "s6000 - Stretch software configurable processor"
85 select VARIANT_IRQ_SWITCH
86 select ARCH_REQUIRE_GPIOLIB
87 select XTENSA_CALIBRATE_CCOUNT
90 config XTENSA_UNALIGNED_USER
91 bool "Unaligned memory access in use space"
93 The Xtensa architecture currently does not handle unaligned
94 memory accesses in hardware but through an exception handler.
95 Per default, unaligned memory accesses are disabled in user space.
97 Say Y here to enable unaligned memory access in user space.
99 source "kernel/Kconfig.preempt"
101 config MATH_EMULATION
102 bool "Math emulation"
104 Can we use information of configuration file?
106 config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
107 bool "Initialize Xtensa MMU inside the Linux kernel code"
110 Earlier version initialized the MMU in the exception vector
111 before jumping to _startup in head.S and had an advantage that
112 it was possible to place a software breakpoint at 'reset' and
113 then enter your normal kernel breakpoints once the MMU was mapped
114 to the kernel mappings (0XC0000000).
116 This unfortunately doesn't work for U-Boot and likley also wont
117 work for using KEXEC to have a hot kernel ready for doing a
120 So now the MMU is initialized in head.S but it's necessary to
121 use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup.
122 xt-gdb can't place a Software Breakpoint in the 0XD region prior
123 to mapping the MMU and after mapping even if the area of low memory
124 was mapped gdb wouldn't remove the breakpoint on hitting it as the
125 PC wouldn't match. Since Hardware Breakpoints are recommended for
126 Linux configurations it seems reasonable to just assume they exist
127 and leave this older mechanism for unfortunate souls that choose
128 not to follow Tensilica's recommendation.
130 Selecting this will cause U-Boot to set the KERNEL Load and Entry
131 address at 0x00003000 instead of the mapped std of 0xD0003000.
137 config XTENSA_CALIBRATE_CCOUNT
140 On some platforms (XT2000, for example), the CPU clock rate can
141 vary. The frequency can be determined, however, by measuring
142 against a well known, fixed frequency, such as an UART oscillator.
144 config SERIAL_CONSOLE
147 config XTENSA_ISS_NETWORK
156 Find out whether you have a PCI motherboard. PCI is the name of a
157 bus system, i.e. the way the CPU talks to the other stuff inside
158 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
159 VESA. If you have PCI, say Y, otherwise N.
161 source "drivers/pci/Kconfig"
165 menu "Platform options"
168 prompt "Xtensa System Type"
169 default XTENSA_PLATFORM_ISS
171 config XTENSA_PLATFORM_ISS
174 select XTENSA_CALIBRATE_CCOUNT
175 select SERIAL_CONSOLE
176 select XTENSA_ISS_NETWORK
178 ISS is an acronym for Tensilica's Instruction Set Simulator.
180 config XTENSA_PLATFORM_XT2000
183 XT2000 is the name of Tensilica's feature-rich emulation platform.
184 This hardware is capable of running a full Linux distribution.
186 config XTENSA_PLATFORM_S6105
188 select SERIAL_CONSOLE
191 config XTENSA_PLATFORM_XTFPGA
193 select SERIAL_CONSOLE
195 select XTENSA_CALIBRATE_CCOUNT
197 XTFPGA is the name of Tensilica board family (LX60, LX110, LX200, ML605).
198 This hardware is capable of running a full Linux distribution.
203 config XTENSA_CPU_CLOCK
204 int "CPU clock rate [MHz]"
205 depends on !XTENSA_CALIBRATE_CCOUNT
208 config GENERIC_CALIBRATE_DELAY
209 bool "Auto calibration of the BogoMIPS value"
211 The BogoMIPS value can easily be derived from the CPU frequency.
214 bool "Default bootloader kernel arguments"
217 string "Initial kernel command string"
218 depends on CMDLINE_BOOL
219 default "console=ttyS0,38400 root=/dev/ram"
221 On some architectures (EBSA110 and CATS), there is currently no way
222 for the boot loader to pass arguments to the kernel. For these
223 architectures, you should supply some command-line options at build
224 time by entering them here. As a minimum, you should specify the
225 memory size and the root device (e.g., mem=64M root=/dev/nfs).
228 bool "Flattened Device Tree support"
230 select OF_EARLY_FLATTREE
232 Include support for flattened device tree machine descriptions.
235 string "DTB to build into the kernel image"
238 config BLK_DEV_SIMDISK
239 tristate "Host file-based simulated block device support"
241 depends on XTENSA_PLATFORM_ISS
243 Create block devices that map to files in the host file system.
244 Device binding to host file may be changed at runtime via proc
245 interface provided the device is not in use.
247 config BLK_DEV_SIMDISK_COUNT
248 int "Number of host file-based simulated block devices"
250 depends on BLK_DEV_SIMDISK
253 This is the default minimal number of created block devices.
254 Kernel/module parameter 'simdisk_count' may be used to change this
255 value at runtime. More file names (but no more than 10) may be
256 specified as parameters, simdisk_count grows accordingly.
258 config SIMDISK0_FILENAME
259 string "Host filename for the first simulated device"
260 depends on BLK_DEV_SIMDISK = y
263 Attach a first simdisk to a host file. Conventionally, this file
264 contains a root file system.
266 config SIMDISK1_FILENAME
267 string "Host filename for the second simulated device"
268 depends on BLK_DEV_SIMDISK = y && BLK_DEV_SIMDISK_COUNT != 1
271 Another simulated disk in a host file for a buildroot-independent
276 source "drivers/pcmcia/Kconfig"
278 source "drivers/pci/hotplug/Kconfig"
282 menu "Executable file formats"
284 source "fs/Kconfig.binfmt"
290 source "drivers/Kconfig"
294 source "arch/xtensa/Kconfig.debug"
296 source "security/Kconfig"
298 source "crypto/Kconfig"