1 # For a description of the syntax of this configuration file,
2 # see Documentation/kbuild/kconfig-language.txt.
4 mainmenu "Linux/Xtensa Kernel Configuration"
19 Xtensa processors are 32-bit RISC machines designed by Tensilica
20 primarily for embedded systems. These processors are both
21 configurable and extensible. The Linux port to the Xtensa
22 architecture supports all processor configurations and extensions,
23 with reasonable minimum requirements. The Xtensa Linux project has
24 a home page at <http://xtensa.sourceforge.net/>.
26 config RWSEM_XCHGADD_ALGORITHM
30 config GENERIC_FIND_NEXT_BIT
34 config GENERIC_HWEIGHT
38 config GENERIC_HARDIRQS
42 config ARCH_HAS_ILOG2_U32
46 config ARCH_HAS_ILOG2_U64
58 source "kernel/Kconfig.freezer"
60 menu "Processor type and features"
63 prompt "Xtensa Processor Configuration"
64 default XTENSA_VARIANT_FSF
66 config XTENSA_VARIANT_FSF
67 bool "fsf - default (not generic) configuration"
69 config XTENSA_VARIANT_DC232B
70 bool "dc232b - Diamond 232L Standard Core Rev.B (LE)"
72 This variant refers to Tensilica's Diamond 232L Standard core Rev.B (LE).
79 config XTENSA_UNALIGNED_USER
80 bool "Unaligned memory access in use space"
82 The Xtensa architecture currently does not handle unaligned
83 memory accesses in hardware but through an exception handler.
84 Per default, unaligned memory accesses are disabled in user space.
86 Say Y here to enable unaligned memory access in user space.
89 bool "Preemptible Kernel"
91 This option reduces the latency of the kernel when reacting to
92 real-time or interactive events by allowing a low priority process to
93 be preempted even if it is in kernel mode executing a system call.
94 Unfortunately the kernel code has some race conditions if both
95 CONFIG_SMP and CONFIG_PREEMPT are enabled, so this option is
96 currently disabled if you are building an SMP kernel.
98 Say Y here if you are building a kernel for a desktop, embedded
99 or real-time system. Say N if you are unsure.
101 config MATH_EMULATION
102 bool "Math emulation"
104 Can we use information of configuration file?
107 bool "High memory support"
111 menu "Platform options"
114 prompt "Xtensa System Type"
115 default XTENSA_PLATFORM_ISS
117 config XTENSA_PLATFORM_ISS
120 ISS is an acronym for Tensilica's Instruction Set Simulator.
122 config XTENSA_PLATFORM_XT2000
125 XT2000 is the name of Tensilica's feature-rich emulation platform.
126 This hardware is capable of running a full Linux distribution.
131 config XTENSA_CALIBRATE_CCOUNT
132 bool "Auto calibration of the CPU clock rate"
134 On some platforms (XT2000, for example), the CPU clock rate can
135 vary. The frequency can be determined, however, by measuring
136 against a well known, fixed frequency, such as an UART oscillator.
138 config XTENSA_CPU_CLOCK
139 int "CPU clock rate [MHz]"
140 depends on !XTENSA_CALIBRATE_CCOUNT
143 config GENERIC_CALIBRATE_DELAY
144 bool "Auto calibration of the BogoMIPS value"
146 The BogoMIPS value can easily be derived from the CPU frequency.
149 bool "Default bootloader kernel arguments"
152 string "Initial kernel command string"
153 depends on CMDLINE_BOOL
154 default "console=ttyS0,38400 root=/dev/ram"
156 On some architectures (EBSA110 and CATS), there is currently no way
157 for the boot loader to pass arguments to the kernel. For these
158 architectures, you should supply some command-line options at build
159 time by entering them here. As a minimum, you should specify the
160 memory size and the root device (e.g., mem=64M root=/dev/nfs).
162 config SERIAL_CONSOLE
164 depends on XTENSA_PLATFORM_ISS
167 config XTENSA_ISS_NETWORK
169 depends on XTENSA_PLATFORM_ISS
179 bool "PCI support" if !XTENSA_PLATFORM_ISS
180 depends on !XTENSA_PLATFORM_ISS
183 Find out whether you have a PCI motherboard. PCI is the name of a
184 bus system, i.e. the way the CPU talks to the other stuff inside
185 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
186 VESA. If you have PCI, say Y, otherwise N.
188 source "drivers/pci/Kconfig"
192 bool "Support for hot-pluggable devices"
194 Say Y here if you want to plug devices into your computer while
195 the system is running, and be able to use them quickly. In many
196 cases, the devices can likewise be unplugged at any time too.
198 One well known example of this is PCMCIA- or PC-cards, credit-card
199 size devices such as network cards, modems or hard drives which are
200 plugged into slots found on all modern laptop computers. Another
201 example, used on modern desktops as well as laptops, is USB.
203 Enable HOTPLUG and build a modular kernel. Get agent software
204 (from <http://linux-hotplug.sourceforge.net/>) and install it.
205 Then your kernel will automatically call out to a user mode "policy
206 agent" (/sbin/hotplug) to load modules and set up software needed
207 to use devices as you hotplug them.
209 source "drivers/pcmcia/Kconfig"
211 source "drivers/pci/hotplug/Kconfig"
215 menu "Executable file formats"
223 If you enabled support for /proc file system then the file
224 /proc/kcore will contain the kernel core image in ELF format. This
227 $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
229 This is especially useful if you have compiled the kernel with the
230 "-g" option to preserve debugging information. It is mainly used
231 for examining kernel data structures on the live kernel.
233 source "fs/Kconfig.binfmt"
239 source "drivers/Kconfig"
243 menu "Xtensa initrd options"
244 depends on BLK_DEV_INITRD
246 config EMBEDDED_RAMDISK
247 bool "Embed root filesystem ramdisk into the kernel"
249 config EMBEDDED_RAMDISK_IMAGE
250 string "Filename of gzipped ramdisk image"
251 depends on EMBEDDED_RAMDISK
254 This is the filename of the ramdisk image to be built into the
255 kernel. Relative pathnames are relative to arch/xtensa/boot/ramdisk/.
256 The ramdisk image is not part of the kernel distribution; you must
257 provide one yourself.
260 source "arch/xtensa/Kconfig.debug"
262 source "security/Kconfig"
264 source "crypto/Kconfig"