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
74 config XTENSA_UNALIGNED_USER
75 bool "Unaligned memory access in use space"
77 The Xtensa architecture currently does not handle unaligned
78 memory accesses in hardware but through an exception handler.
79 Per default, unaligned memory accesses are disabled in user space.
81 Say Y here to enable unaligned memory access in user space.
84 bool "Preemptible Kernel"
86 This option reduces the latency of the kernel when reacting to
87 real-time or interactive events by allowing a low priority process to
88 be preempted even if it is in kernel mode executing a system call.
89 Unfortunately the kernel code has some race conditions if both
90 CONFIG_SMP and CONFIG_PREEMPT are enabled, so this option is
91 currently disabled if you are building an SMP kernel.
93 Say Y here if you are building a kernel for a desktop, embedded
94 or real-time system. Say N if you are unsure.
99 Can we use information of configuration file?
102 bool "High memory support"
106 menu "Platform options"
109 prompt "Xtensa System Type"
110 default XTENSA_PLATFORM_ISS
112 config XTENSA_PLATFORM_ISS
115 ISS is an acronym for Tensilica's Instruction Set Simulator.
117 config XTENSA_PLATFORM_XT2000
120 XT2000 is the name of Tensilica's feature-rich emulation platform.
121 This hardware is capable of running a full Linux distribution.
126 config XTENSA_CALIBRATE_CCOUNT
127 bool "Auto calibration of the CPU clock rate"
129 On some platforms (XT2000, for example), the CPU clock rate can
130 vary. The frequency can be determined, however, by measuring
131 against a well known, fixed frequency, such as an UART oscillator.
133 config XTENSA_CPU_CLOCK
134 int "CPU clock rate [MHz]"
135 depends on !XTENSA_CALIBRATE_CCOUNT
138 config GENERIC_CALIBRATE_DELAY
139 bool "Auto calibration of the BogoMIPS value"
141 The BogoMIPS value can easily be derived from the CPU frequency.
144 bool "Default bootloader kernel arguments"
147 string "Initial kernel command string"
148 depends on CMDLINE_BOOL
149 default "console=ttyS0,38400 root=/dev/ram"
151 On some architectures (EBSA110 and CATS), there is currently no way
152 for the boot loader to pass arguments to the kernel. For these
153 architectures, you should supply some command-line options at build
154 time by entering them here. As a minimum, you should specify the
155 memory size and the root device (e.g., mem=64M root=/dev/nfs).
157 config SERIAL_CONSOLE
159 depends on XTENSA_PLATFORM_ISS
162 config XTENSA_ISS_NETWORK
164 depends on XTENSA_PLATFORM_ISS
174 bool "PCI support" if !XTENSA_PLATFORM_ISS
175 depends on !XTENSA_PLATFORM_ISS
178 Find out whether you have a PCI motherboard. PCI is the name of a
179 bus system, i.e. the way the CPU talks to the other stuff inside
180 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
181 VESA. If you have PCI, say Y, otherwise N.
183 source "drivers/pci/Kconfig"
187 bool "Support for hot-pluggable devices"
189 Say Y here if you want to plug devices into your computer while
190 the system is running, and be able to use them quickly. In many
191 cases, the devices can likewise be unplugged at any time too.
193 One well known example of this is PCMCIA- or PC-cards, credit-card
194 size devices such as network cards, modems or hard drives which are
195 plugged into slots found on all modern laptop computers. Another
196 example, used on modern desktops as well as laptops, is USB.
198 Enable HOTPLUG and build a modular kernel. Get agent software
199 (from <http://linux-hotplug.sourceforge.net/>) and install it.
200 Then your kernel will automatically call out to a user mode "policy
201 agent" (/sbin/hotplug) to load modules and set up software needed
202 to use devices as you hotplug them.
204 source "drivers/pcmcia/Kconfig"
206 source "drivers/pci/hotplug/Kconfig"
210 menu "Executable file formats"
218 If you enabled support for /proc file system then the file
219 /proc/kcore will contain the kernel core image in ELF format. This
222 $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
224 This is especially useful if you have compiled the kernel with the
225 "-g" option to preserve debugging information. It is mainly used
226 for examining kernel data structures on the live kernel.
228 source "fs/Kconfig.binfmt"
234 source "drivers/Kconfig"
238 menu "Xtensa initrd options"
239 depends on BLK_DEV_INITRD
241 config EMBEDDED_RAMDISK
242 bool "Embed root filesystem ramdisk into the kernel"
244 config EMBEDDED_RAMDISK_IMAGE
245 string "Filename of gzipped ramdisk image"
246 depends on EMBEDDED_RAMDISK
249 This is the filename of the ramdisk image to be built into the
250 kernel. Relative pathnames are relative to arch/xtensa/boot/ramdisk/.
251 The ramdisk image is not part of the kernel distribution; you must
252 provide one yourself.
255 source "arch/xtensa/Kconfig.debug"
257 source "security/Kconfig"
259 source "crypto/Kconfig"