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
58 menu "Processor type and features"
61 prompt "Xtensa Processor Configuration"
62 default XTENSA_VARIANT_FSF
64 config XTENSA_VARIANT_FSF
72 config XTENSA_UNALIGNED_USER
73 bool "Unaligned memory access in use space"
75 The Xtensa architecture currently does not handle unaligned
76 memory accesses in hardware but through an exception handler.
77 Per default, unaligned memory accesses are disabled in user space.
79 Say Y here to enable unaligned memory access in user space.
82 bool "Preemptible Kernel"
84 This option reduces the latency of the kernel when reacting to
85 real-time or interactive events by allowing a low priority process to
86 be preempted even if it is in kernel mode executing a system call.
87 Unfortunately the kernel code has some race conditions if both
88 CONFIG_SMP and CONFIG_PREEMPT are enabled, so this option is
89 currently disabled if you are building an SMP kernel.
91 Say Y here if you are building a kernel for a desktop, embedded
92 or real-time system. Say N if you are unsure.
97 Can we use information of configuration file?
100 bool "High memory support"
104 menu "Platform options"
107 prompt "Xtensa System Type"
108 default XTENSA_PLATFORM_ISS
110 config XTENSA_PLATFORM_ISS
113 ISS is an acronym for Tensilica's Instruction Set Simulator.
115 config XTENSA_PLATFORM_XT2000
118 XT2000 is the name of Tensilica's feature-rich emulation platform.
119 This hardware is capable of running a full Linux distribution.
124 config XTENSA_CALIBRATE_CCOUNT
125 bool "Auto calibration of the CPU clock rate"
127 On some platforms (XT2000, for example), the CPU clock rate can
128 vary. The frequency can be determined, however, by measuring
129 against a well known, fixed frequency, such as an UART oscillator.
131 config XTENSA_CPU_CLOCK
132 int "CPU clock rate [MHz]"
133 depends on !XTENSA_CALIBRATE_CCOUNT
136 config GENERIC_CALIBRATE_DELAY
137 bool "Auto calibration of the BogoMIPS value"
139 The BogoMIPS value can easily be derived from the CPU frequency.
142 bool "Default bootloader kernel arguments"
145 string "Initial kernel command string"
146 depends on CMDLINE_BOOL
147 default "console=ttyS0,38400 root=/dev/ram"
149 On some architectures (EBSA110 and CATS), there is currently no way
150 for the boot loader to pass arguments to the kernel. For these
151 architectures, you should supply some command-line options at build
152 time by entering them here. As a minimum, you should specify the
153 memory size and the root device (e.g., mem=64M root=/dev/nfs).
155 config SERIAL_CONSOLE
157 depends on XTENSA_PLATFORM_ISS
160 config XTENSA_ISS_NETWORK
162 depends on XTENSA_PLATFORM_ISS
172 bool "PCI support" if !XTENSA_PLATFORM_ISS
173 depends on !XTENSA_PLATFORM_ISS
176 Find out whether you have a PCI motherboard. PCI is the name of a
177 bus system, i.e. the way the CPU talks to the other stuff inside
178 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
179 VESA. If you have PCI, say Y, otherwise N.
181 source "drivers/pci/Kconfig"
185 bool "Support for hot-pluggable devices"
187 Say Y here if you want to plug devices into your computer while
188 the system is running, and be able to use them quickly. In many
189 cases, the devices can likewise be unplugged at any time too.
191 One well known example of this is PCMCIA- or PC-cards, credit-card
192 size devices such as network cards, modems or hard drives which are
193 plugged into slots found on all modern laptop computers. Another
194 example, used on modern desktops as well as laptops, is USB.
196 Enable HOTPLUG and KMOD, and build a modular kernel. Get agent
197 software (at <http://linux-hotplug.sourceforge.net/>) and install it.
198 Then your kernel will automatically call out to a user mode "policy
199 agent" (/sbin/hotplug) to load modules and set up software needed
200 to use devices as you hotplug them.
202 source "drivers/pcmcia/Kconfig"
204 source "drivers/pci/hotplug/Kconfig"
208 menu "Executable file formats"
216 If you enabled support for /proc file system then the file
217 /proc/kcore will contain the kernel core image in ELF format. This
220 $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
222 This is especially useful if you have compiled the kernel with the
223 "-g" option to preserve debugging information. It is mainly used
224 for examining kernel data structures on the live kernel.
226 source "fs/Kconfig.binfmt"
232 source "drivers/Kconfig"
236 menu "Xtensa initrd options"
237 depends on BLK_DEV_INITRD
239 config EMBEDDED_RAMDISK
240 bool "Embed root filesystem ramdisk into the kernel"
242 config EMBEDDED_RAMDISK_IMAGE
243 string "Filename of gzipped ramdisk image"
244 depends on EMBEDDED_RAMDISK
247 This is the filename of the ramdisk image to be built into the
248 kernel. Relative pathnames are relative to arch/xtensa/boot/ramdisk/.
249 The ramdisk image is not part of the kernel distribution; you must
250 provide one yourself.
253 source "arch/xtensa/Kconfig.debug"
255 source "security/Kconfig"
257 source "crypto/Kconfig"