1 # For a description of the syntax of this configuration file,
2 # see Documentation/kbuild/kconfig-language.txt.
4 mainmenu "Linux/Xtensa Kernel Configuration"
18 Xtensa processors are 32-bit RISC machines designed by Tensilica
19 primarily for embedded systems. These processors are both
20 configurable and extensible. The Linux port to the Xtensa
21 architecture supports all processor configurations and extensions,
22 with reasonable minimum requirements. The Xtensa Linux project has
23 a home page at <http://xtensa.sourceforge.net/>.
25 config RWSEM_XCHGADD_ALGORITHM
29 config GENERIC_FIND_NEXT_BIT
33 config GENERIC_HWEIGHT
37 config GENERIC_HARDIRQS
41 config ARCH_HAS_ILOG2_U32
45 config ARCH_HAS_ILOG2_U64
54 menu "Processor type and features"
57 prompt "Xtensa Processor Configuration"
58 default XTENSA_VARIANT_FSF
60 config XTENSA_VARIANT_FSF
68 config XTENSA_UNALIGNED_USER
69 bool "Unaligned memory access in use space"
71 The Xtensa architecture currently does not handle unaligned
72 memory accesses in hardware but through an exception handler.
73 Per default, unaligned memory accesses are disabled in user space.
75 Say Y here to enable unaligned memory access in user space.
78 bool "Preemptible Kernel"
80 This option reduces the latency of the kernel when reacting to
81 real-time or interactive events by allowing a low priority process to
82 be preempted even if it is in kernel mode executing a system call.
83 Unfortunately the kernel code has some race conditions if both
84 CONFIG_SMP and CONFIG_PREEMPT are enabled, so this option is
85 currently disabled if you are building an SMP kernel.
87 Say Y here if you are building a kernel for a desktop, embedded
88 or real-time system. Say N if you are unsure.
93 Can we use information of configuration file?
96 bool "High memory support"
100 menu "Platform options"
103 prompt "Xtensa System Type"
104 default XTENSA_PLATFORM_ISS
106 config XTENSA_PLATFORM_ISS
109 ISS is an acronym for Tensilica's Instruction Set Simulator.
111 config XTENSA_PLATFORM_XT2000
114 XT2000 is the name of Tensilica's feature-rich emulation platform.
115 This hardware is capable of running a full Linux distribution.
120 config XTENSA_CALIBRATE_CCOUNT
121 bool "Auto calibration of the CPU clock rate"
123 On some platforms (XT2000, for example), the CPU clock rate can
124 vary. The frequency can be determined, however, by measuring
125 against a well known, fixed frequency, such as an UART oscillator.
127 config XTENSA_CPU_CLOCK
128 int "CPU clock rate [MHz]"
129 depends on !XTENSA_CALIBRATE_CCOUNT
132 config GENERIC_CALIBRATE_DELAY
133 bool "Auto calibration of the BogoMIPS value"
135 The BogoMIPS value can easily be derived from the CPU frequency.
138 bool "Default bootloader kernel arguments"
141 string "Initial kernel command string"
142 depends on CMDLINE_BOOL
143 default "console=ttyS0,38400 root=/dev/ram"
145 On some architectures (EBSA110 and CATS), there is currently no way
146 for the boot loader to pass arguments to the kernel. For these
147 architectures, you should supply some command-line options at build
148 time by entering them here. As a minimum, you should specify the
149 memory size and the root device (e.g., mem=64M root=/dev/nfs).
151 config SERIAL_CONSOLE
153 depends on XTENSA_PLATFORM_ISS
156 config XTENSA_ISS_NETWORK
158 depends on XTENSA_PLATFORM_ISS
168 bool "PCI support" if !XTENSA_PLATFORM_ISS
169 depends on !XTENSA_PLATFORM_ISS
172 Find out whether you have a PCI motherboard. PCI is the name of a
173 bus system, i.e. the way the CPU talks to the other stuff inside
174 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
175 VESA. If you have PCI, say Y, otherwise N.
177 source "drivers/pci/Kconfig"
181 bool "Support for hot-pluggable devices"
183 Say Y here if you want to plug devices into your computer while
184 the system is running, and be able to use them quickly. In many
185 cases, the devices can likewise be unplugged at any time too.
187 One well known example of this is PCMCIA- or PC-cards, credit-card
188 size devices such as network cards, modems or hard drives which are
189 plugged into slots found on all modern laptop computers. Another
190 example, used on modern desktops as well as laptops, is USB.
192 Enable HOTPLUG and KMOD, and build a modular kernel. Get agent
193 software (at <http://linux-hotplug.sourceforge.net/>) and install it.
194 Then your kernel will automatically call out to a user mode "policy
195 agent" (/sbin/hotplug) to load modules and set up software needed
196 to use devices as you hotplug them.
198 source "drivers/pcmcia/Kconfig"
200 source "drivers/pci/hotplug/Kconfig"
204 menu "Executable file formats"
212 If you enabled support for /proc file system then the file
213 /proc/kcore will contain the kernel core image in ELF format. This
216 $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
218 This is especially useful if you have compiled the kernel with the
219 "-g" option to preserve debugging information. It is mainly used
220 for examining kernel data structures on the live kernel.
222 source "fs/Kconfig.binfmt"
228 source "drivers/Kconfig"
232 menu "Xtensa initrd options"
233 depends on BLK_DEV_INITRD
235 config EMBEDDED_RAMDISK
236 bool "Embed root filesystem ramdisk into the kernel"
238 config EMBEDDED_RAMDISK_IMAGE
239 string "Filename of gzipped ramdisk image"
240 depends on EMBEDDED_RAMDISK
243 This is the filename of the ramdisk image to be built into the
244 kernel. Relative pathnames are relative to arch/xtensa/boot/ramdisk/.
245 The ramdisk image is not part of the kernel distribution; you must
246 provide one yourself.
249 source "kernel/Kconfig.instrumentation"
251 source "arch/xtensa/Kconfig.debug"
253 source "security/Kconfig"
255 source "crypto/Kconfig"