10 select HAVE_GENERIC_HARDIRQS
11 select GENERIC_IRQ_SHOW
13 Xtensa processors are 32-bit RISC machines designed by Tensilica
14 primarily for embedded systems. These processors are both
15 configurable and extensible. The Linux port to the Xtensa
16 architecture supports all processor configurations and extensions,
17 with reasonable minimum requirements. The Xtensa Linux project has
18 a home page at <http://xtensa.sourceforge.net/>.
20 config RWSEM_XCHGADD_ALGORITHM
23 config GENERIC_HWEIGHT
29 config ARCH_HAS_ILOG2_U32
32 config ARCH_HAS_ILOG2_U64
43 source "kernel/Kconfig.freezer"
48 config VARIANT_IRQ_SWITCH
51 menu "Processor type and features"
54 prompt "Xtensa Processor Configuration"
55 default XTENSA_VARIANT_FSF
57 config XTENSA_VARIANT_FSF
58 bool "fsf - default (not generic) configuration"
61 config XTENSA_VARIANT_DC232B
62 bool "dc232b - Diamond 232L Standard Core Rev.B (LE)"
65 This variant refers to Tensilica's Diamond 232L Standard core Rev.B (LE).
67 config XTENSA_VARIANT_S6000
68 bool "s6000 - Stretch software configurable processor"
69 select VARIANT_IRQ_SWITCH
70 select ARCH_REQUIRE_GPIOLIB
71 select XTENSA_CALIBRATE_CCOUNT
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?
103 config XTENSA_CALIBRATE_CCOUNT
106 On some platforms (XT2000, for example), the CPU clock rate can
107 vary. The frequency can be determined, however, by measuring
108 against a well known, fixed frequency, such as an UART oscillator.
110 config SERIAL_CONSOLE
113 config XTENSA_ISS_NETWORK
122 Find out whether you have a PCI motherboard. PCI is the name of a
123 bus system, i.e. the way the CPU talks to the other stuff inside
124 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
125 VESA. If you have PCI, say Y, otherwise N.
127 source "drivers/pci/Kconfig"
131 menu "Platform options"
134 prompt "Xtensa System Type"
135 default XTENSA_PLATFORM_ISS
137 config XTENSA_PLATFORM_ISS
139 select XTENSA_CALIBRATE_CCOUNT
140 select SERIAL_CONSOLE
141 select XTENSA_ISS_NETWORK
143 ISS is an acronym for Tensilica's Instruction Set Simulator.
145 config XTENSA_PLATFORM_XT2000
148 XT2000 is the name of Tensilica's feature-rich emulation platform.
149 This hardware is capable of running a full Linux distribution.
151 config XTENSA_PLATFORM_S6105
153 select SERIAL_CONSOLE
158 config XTENSA_CPU_CLOCK
159 int "CPU clock rate [MHz]"
160 depends on !XTENSA_CALIBRATE_CCOUNT
163 config GENERIC_CALIBRATE_DELAY
164 bool "Auto calibration of the BogoMIPS value"
166 The BogoMIPS value can easily be derived from the CPU frequency.
169 bool "Default bootloader kernel arguments"
172 string "Initial kernel command string"
173 depends on CMDLINE_BOOL
174 default "console=ttyS0,38400 root=/dev/ram"
176 On some architectures (EBSA110 and CATS), there is currently no way
177 for the boot loader to pass arguments to the kernel. For these
178 architectures, you should supply some command-line options at build
179 time by entering them here. As a minimum, you should specify the
180 memory size and the root device (e.g., mem=64M root=/dev/nfs).
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 build a modular kernel. Get agent software
197 (from <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"
215 If you enabled support for /proc file system then the file
216 /proc/kcore will contain the kernel core image in ELF format. This
219 $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
221 This is especially useful if you have compiled the kernel with the
222 "-g" option to preserve debugging information. It is mainly used
223 for examining kernel data structures on the live kernel.
225 source "fs/Kconfig.binfmt"
231 source "drivers/Kconfig"
235 menu "Xtensa initrd options"
236 depends on BLK_DEV_INITRD
238 config EMBEDDED_RAMDISK
239 bool "Embed root filesystem ramdisk into the kernel"
241 config EMBEDDED_RAMDISK_IMAGE
242 string "Filename of gzipped ramdisk image"
243 depends on EMBEDDED_RAMDISK
246 This is the filename of the ramdisk image to be built into the
247 kernel. Relative pathnames are relative to arch/xtensa/boot/ramdisk/.
248 The ramdisk image is not part of the kernel distribution; you must
249 provide one yourself.
252 source "arch/xtensa/Kconfig.debug"
254 source "security/Kconfig"
256 source "crypto/Kconfig"