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?
108 menu "Platform options"
111 prompt "Xtensa System Type"
112 default XTENSA_PLATFORM_ISS
114 config XTENSA_PLATFORM_ISS
117 ISS is an acronym for Tensilica's Instruction Set Simulator.
119 config XTENSA_PLATFORM_XT2000
122 XT2000 is the name of Tensilica's feature-rich emulation platform.
123 This hardware is capable of running a full Linux distribution.
128 config XTENSA_CALIBRATE_CCOUNT
129 bool "Auto calibration of the CPU clock rate"
131 On some platforms (XT2000, for example), the CPU clock rate can
132 vary. The frequency can be determined, however, by measuring
133 against a well known, fixed frequency, such as an UART oscillator.
135 config XTENSA_CPU_CLOCK
136 int "CPU clock rate [MHz]"
137 depends on !XTENSA_CALIBRATE_CCOUNT
140 config GENERIC_CALIBRATE_DELAY
141 bool "Auto calibration of the BogoMIPS value"
143 The BogoMIPS value can easily be derived from the CPU frequency.
146 bool "Default bootloader kernel arguments"
149 string "Initial kernel command string"
150 depends on CMDLINE_BOOL
151 default "console=ttyS0,38400 root=/dev/ram"
153 On some architectures (EBSA110 and CATS), there is currently no way
154 for the boot loader to pass arguments to the kernel. For these
155 architectures, you should supply some command-line options at build
156 time by entering them here. As a minimum, you should specify the
157 memory size and the root device (e.g., mem=64M root=/dev/nfs).
159 config SERIAL_CONSOLE
161 depends on XTENSA_PLATFORM_ISS
164 config XTENSA_ISS_NETWORK
166 depends on XTENSA_PLATFORM_ISS
176 bool "PCI support" if !XTENSA_PLATFORM_ISS
177 depends on !XTENSA_PLATFORM_ISS
180 Find out whether you have a PCI motherboard. PCI is the name of a
181 bus system, i.e. the way the CPU talks to the other stuff inside
182 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
183 VESA. If you have PCI, say Y, otherwise N.
185 source "drivers/pci/Kconfig"
189 bool "Support for hot-pluggable devices"
191 Say Y here if you want to plug devices into your computer while
192 the system is running, and be able to use them quickly. In many
193 cases, the devices can likewise be unplugged at any time too.
195 One well known example of this is PCMCIA- or PC-cards, credit-card
196 size devices such as network cards, modems or hard drives which are
197 plugged into slots found on all modern laptop computers. Another
198 example, used on modern desktops as well as laptops, is USB.
200 Enable HOTPLUG and build a modular kernel. Get agent software
201 (from <http://linux-hotplug.sourceforge.net/>) and install it.
202 Then your kernel will automatically call out to a user mode "policy
203 agent" (/sbin/hotplug) to load modules and set up software needed
204 to use devices as you hotplug them.
206 source "drivers/pcmcia/Kconfig"
208 source "drivers/pci/hotplug/Kconfig"
212 menu "Executable file formats"
220 If you enabled support for /proc file system then the file
221 /proc/kcore will contain the kernel core image in ELF format. This
224 $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
226 This is especially useful if you have compiled the kernel with the
227 "-g" option to preserve debugging information. It is mainly used
228 for examining kernel data structures on the live kernel.
230 source "fs/Kconfig.binfmt"
236 source "drivers/Kconfig"
240 menu "Xtensa initrd options"
241 depends on BLK_DEV_INITRD
243 config EMBEDDED_RAMDISK
244 bool "Embed root filesystem ramdisk into the kernel"
246 config EMBEDDED_RAMDISK_IMAGE
247 string "Filename of gzipped ramdisk image"
248 depends on EMBEDDED_RAMDISK
251 This is the filename of the ramdisk image to be built into the
252 kernel. Relative pathnames are relative to arch/xtensa/boot/ramdisk/.
253 The ramdisk image is not part of the kernel distribution; you must
254 provide one yourself.
257 source "arch/xtensa/Kconfig.debug"
259 source "security/Kconfig"
261 source "crypto/Kconfig"