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
59 menu "Processor type and features"
62 prompt "Xtensa Processor Configuration"
63 default XTENSA_VARIANT_FSF
65 config XTENSA_VARIANT_FSF
73 config XTENSA_UNALIGNED_USER
74 bool "Unaligned memory access in use space"
76 The Xtensa architecture currently does not handle unaligned
77 memory accesses in hardware but through an exception handler.
78 Per default, unaligned memory accesses are disabled in user space.
80 Say Y here to enable unaligned memory access in user space.
83 bool "Preemptible Kernel"
85 This option reduces the latency of the kernel when reacting to
86 real-time or interactive events by allowing a low priority process to
87 be preempted even if it is in kernel mode executing a system call.
88 Unfortunately the kernel code has some race conditions if both
89 CONFIG_SMP and CONFIG_PREEMPT are enabled, so this option is
90 currently disabled if you are building an SMP kernel.
92 Say Y here if you are building a kernel for a desktop, embedded
93 or real-time system. Say N if you are unsure.
98 Can we use information of configuration file?
101 bool "High memory support"
105 menu "Platform options"
108 prompt "Xtensa System Type"
109 default XTENSA_PLATFORM_ISS
111 config XTENSA_PLATFORM_ISS
114 ISS is an acronym for Tensilica's Instruction Set Simulator.
116 config XTENSA_PLATFORM_XT2000
119 XT2000 is the name of Tensilica's feature-rich emulation platform.
120 This hardware is capable of running a full Linux distribution.
125 config XTENSA_CALIBRATE_CCOUNT
126 bool "Auto calibration of the CPU clock rate"
128 On some platforms (XT2000, for example), the CPU clock rate can
129 vary. The frequency can be determined, however, by measuring
130 against a well known, fixed frequency, such as an UART oscillator.
132 config XTENSA_CPU_CLOCK
133 int "CPU clock rate [MHz]"
134 depends on !XTENSA_CALIBRATE_CCOUNT
137 config GENERIC_CALIBRATE_DELAY
138 bool "Auto calibration of the BogoMIPS value"
140 The BogoMIPS value can easily be derived from the CPU frequency.
143 bool "Default bootloader kernel arguments"
146 string "Initial kernel command string"
147 depends on CMDLINE_BOOL
148 default "console=ttyS0,38400 root=/dev/ram"
150 On some architectures (EBSA110 and CATS), there is currently no way
151 for the boot loader to pass arguments to the kernel. For these
152 architectures, you should supply some command-line options at build
153 time by entering them here. As a minimum, you should specify the
154 memory size and the root device (e.g., mem=64M root=/dev/nfs).
156 config SERIAL_CONSOLE
158 depends on XTENSA_PLATFORM_ISS
161 config XTENSA_ISS_NETWORK
163 depends on XTENSA_PLATFORM_ISS
173 bool "PCI support" if !XTENSA_PLATFORM_ISS
174 depends on !XTENSA_PLATFORM_ISS
177 Find out whether you have a PCI motherboard. PCI is the name of a
178 bus system, i.e. the way the CPU talks to the other stuff inside
179 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
180 VESA. If you have PCI, say Y, otherwise N.
182 source "drivers/pci/Kconfig"
186 bool "Support for hot-pluggable devices"
188 Say Y here if you want to plug devices into your computer while
189 the system is running, and be able to use them quickly. In many
190 cases, the devices can likewise be unplugged at any time too.
192 One well known example of this is PCMCIA- or PC-cards, credit-card
193 size devices such as network cards, modems or hard drives which are
194 plugged into slots found on all modern laptop computers. Another
195 example, used on modern desktops as well as laptops, is USB.
197 Enable HOTPLUG and build a modular kernel. Get agent software
198 (from <http://linux-hotplug.sourceforge.net/>) and install it.
199 Then your kernel will automatically call out to a user mode "policy
200 agent" (/sbin/hotplug) to load modules and set up software needed
201 to use devices as you hotplug them.
203 source "drivers/pcmcia/Kconfig"
205 source "drivers/pci/hotplug/Kconfig"
209 menu "Executable file formats"
217 If you enabled support for /proc file system then the file
218 /proc/kcore will contain the kernel core image in ELF format. This
221 $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
223 This is especially useful if you have compiled the kernel with the
224 "-g" option to preserve debugging information. It is mainly used
225 for examining kernel data structures on the live kernel.
227 source "fs/Kconfig.binfmt"
233 source "drivers/Kconfig"
237 menu "Xtensa initrd options"
238 depends on BLK_DEV_INITRD
240 config EMBEDDED_RAMDISK
241 bool "Embed root filesystem ramdisk into the kernel"
243 config EMBEDDED_RAMDISK_IMAGE
244 string "Filename of gzipped ramdisk image"
245 depends on EMBEDDED_RAMDISK
248 This is the filename of the ramdisk image to be built into the
249 kernel. Relative pathnames are relative to arch/xtensa/boot/ramdisk/.
250 The ramdisk image is not part of the kernel distribution; you must
251 provide one yourself.
254 source "arch/xtensa/Kconfig.debug"
256 source "security/Kconfig"
258 source "crypto/Kconfig"