mirror of
https://github.com/torvalds/linux.git
synced 2024-11-27 22:51:35 +00:00
f0d1b0b30d
This facility provides three entry points:
ilog2() Log base 2 of unsigned long
ilog2_u32() Log base 2 of u32
ilog2_u64() Log base 2 of u64
These facilities can either be used inside functions on dynamic data:
int do_something(long q)
{
...;
y = ilog2(x)
...;
}
Or can be used to statically initialise global variables with constant values:
unsigned n = ilog2(27);
When performing static initialisation, the compiler will report "error:
initializer element is not constant" if asked to take a log of zero or of
something not reducible to a constant. They treat negative numbers as
unsigned.
When not dealing with a constant, they fall back to using fls() which permits
them to use arch-specific log calculation instructions - such as BSR on
x86/x86_64 or SCAN on FRV - if available.
[akpm@osdl.org: MMC fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Wojtek Kaniewski <wojtekka@toxygen.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
201 lines
3.7 KiB
Plaintext
201 lines
3.7 KiB
Plaintext
#
|
|
# For a description of the syntax of this configuration file,
|
|
# see the Configure script.
|
|
#
|
|
|
|
mainmenu "Linux/CRIS Kernel Configuration"
|
|
|
|
config MMU
|
|
bool
|
|
default y
|
|
|
|
config RWSEM_GENERIC_SPINLOCK
|
|
bool
|
|
default y
|
|
|
|
config RWSEM_XCHGADD_ALGORITHM
|
|
bool
|
|
|
|
config ARCH_HAS_ILOG2_U32
|
|
bool
|
|
default n
|
|
|
|
config ARCH_HAS_ILOG2_U64
|
|
bool
|
|
default n
|
|
|
|
config GENERIC_FIND_NEXT_BIT
|
|
bool
|
|
default y
|
|
|
|
config GENERIC_HWEIGHT
|
|
bool
|
|
default y
|
|
|
|
config GENERIC_CALIBRATE_DELAY
|
|
bool
|
|
default y
|
|
|
|
config IRQ_PER_CPU
|
|
bool
|
|
default y
|
|
|
|
config CRIS
|
|
bool
|
|
default y
|
|
|
|
source "init/Kconfig"
|
|
|
|
menu "General setup"
|
|
|
|
source "fs/Kconfig.binfmt"
|
|
|
|
config ETRAX_CMDLINE
|
|
string "Kernel command line"
|
|
default "root=/dev/mtdblock3"
|
|
help
|
|
Pass additional commands to the kernel.
|
|
|
|
config ETRAX_WATCHDOG
|
|
bool "Enable ETRAX watchdog"
|
|
help
|
|
Enable the built-in watchdog timer support on ETRAX based embedded
|
|
network computers.
|
|
|
|
config ETRAX_WATCHDOG_NICE_DOGGY
|
|
bool "Disable watchdog during Oops printouts"
|
|
depends on ETRAX_WATCHDOG
|
|
help
|
|
By enabling this you make sure that the watchdog does not bite while
|
|
printing oopses. Recommended for development systems but not for
|
|
production releases.
|
|
|
|
config ETRAX_FAST_TIMER
|
|
bool "Enable ETRAX fast timer API"
|
|
help
|
|
This options enables the API to a fast timer implementation using
|
|
timer1 to get sub jiffie resolution timers (primarily one-shot
|
|
timers).
|
|
This is needed if CONFIG_ETRAX_SERIAL_FAST_TIMER is enabled.
|
|
|
|
config PREEMPT
|
|
bool "Preemptible Kernel"
|
|
help
|
|
This option reduces the latency of the kernel when reacting to
|
|
real-time or interactive events by allowing a low priority process to
|
|
be preempted even if it is in kernel mode executing a system call.
|
|
This allows applications to run more reliably even when the system is
|
|
under load.
|
|
|
|
Say Y here if you are building a kernel for a desktop, embedded
|
|
or real-time system. Say N if you are unsure.
|
|
|
|
source mm/Kconfig
|
|
|
|
endmenu
|
|
|
|
menu "Hardware setup"
|
|
|
|
choice
|
|
prompt "Processor type"
|
|
default ETRAX100LX
|
|
|
|
config ETRAX100LX
|
|
bool "ETRAX-100LX-v1"
|
|
help
|
|
Support version 1 of the ETRAX 100LX.
|
|
|
|
config ETRAX100LX_V2
|
|
bool "ETRAX-100LX-v2"
|
|
help
|
|
Support version 2 of the ETRAX 100LX.
|
|
|
|
config SVINTO_SIM
|
|
bool "ETRAX-100LX-for-xsim-simulator"
|
|
help
|
|
Support the xsim ETRAX Simulator.
|
|
|
|
endchoice
|
|
|
|
config ETRAX_ARCH_V10
|
|
bool
|
|
default y if ETRAX100LX || ETRAX100LX_V2
|
|
default n if !(ETRAX100LX || ETRAX100LX_V2)
|
|
|
|
config ETRAX_DRAM_SIZE
|
|
int "DRAM size (dec, in MB)"
|
|
default "8"
|
|
help
|
|
Size of DRAM (decimal in MB) typically 2, 8 or 16.
|
|
|
|
config ETRAX_FLASH_BUSWIDTH
|
|
int "Buswidth of flash in bytes"
|
|
default "2"
|
|
help
|
|
Width in bytes of the Flash bus (1, 2 or 4). Is usually 2.
|
|
|
|
source arch/cris/arch-v10/Kconfig
|
|
|
|
endmenu
|
|
|
|
source "net/Kconfig"
|
|
|
|
# bring in ETRAX built-in drivers
|
|
menu "Drivers for built-in interfaces"
|
|
source arch/cris/arch-v10/drivers/Kconfig
|
|
|
|
endmenu
|
|
|
|
source "drivers/base/Kconfig"
|
|
|
|
# standard linux drivers
|
|
source "drivers/mtd/Kconfig"
|
|
|
|
source "drivers/parport/Kconfig"
|
|
|
|
source "drivers/pnp/Kconfig"
|
|
|
|
source "drivers/block/Kconfig"
|
|
|
|
source "drivers/md/Kconfig"
|
|
|
|
source "drivers/ide/Kconfig"
|
|
|
|
source "drivers/scsi/Kconfig"
|
|
|
|
source "drivers/ieee1394/Kconfig"
|
|
|
|
source "drivers/message/i2o/Kconfig"
|
|
|
|
source "drivers/net/Kconfig"
|
|
|
|
source "drivers/isdn/Kconfig"
|
|
|
|
source "drivers/telephony/Kconfig"
|
|
|
|
source "drivers/cdrom/Kconfig"
|
|
|
|
#
|
|
# input before char - char/joystick depends on it. As does USB.
|
|
#
|
|
source "drivers/input/Kconfig"
|
|
|
|
source "drivers/char/Kconfig"
|
|
|
|
#source drivers/misc/Config.in
|
|
source "drivers/media/Kconfig"
|
|
|
|
source "fs/Kconfig"
|
|
|
|
source "sound/Kconfig"
|
|
|
|
source "drivers/usb/Kconfig"
|
|
|
|
source "arch/cris/Kconfig.debug"
|
|
|
|
source "security/Kconfig"
|
|
|
|
source "crypto/Kconfig"
|
|
|
|
source "lib/Kconfig"
|