kconfig.cputype

linux 内核源代码

config PPC64
	bool "64-bit kernel"
	default n
	help
	  This option selects whether a 32-bit or a 64-bit kernel
	  will be built.

menu "Processor support"
choice
	prompt "Processor Type"
	depends on PPC32
	default 6xx
	help
	  There are five families of 32 bit PowerPC chips supported.
	  The most common ones are the desktop and server CPUs (601, 603,
	  604, 740, 750, 74xx) CPUs from Freescale and IBM, with their
	  embedded 52xx/82xx/83xx/86xx counterparts.
	  The other embeeded parts, namely 4xx, 8xx, e200 (55xx) and e500
	  (85xx) each form a family of their own that is not compatible
	  with the others.

	  If unsure, select 52xx/6xx/7xx/74xx/82xx/83xx/86xx.

config 6xx
	bool "52xx/6xx/7xx/74xx/82xx/83xx/86xx"
	select PPC_FPU

config PPC_85xx
	bool "Freescale 85xx"
	select E500
	select FSL_SOC
	select 85xx
	select WANT_DEVICE_TREE

config PPC_8xx
	bool "Freescale 8xx"
	select FSL_SOC
	select 8xx
	select WANT_DEVICE_TREE
	select PPC_LIB_RHEAP

config 40x
	bool "AMCC 40x"
	select PPC_DCR_NATIVE
	select WANT_DEVICE_TREE

config 44x
	bool "AMCC 44x"
	select PPC_DCR_NATIVE
	select WANT_DEVICE_TREE
	select PPC_UDBG_16550

config E200
	bool "Freescale e200"

endchoice

config POWER4_ONLY
	bool "Optimize for POWER4"
	depends on PPC64
	default n
	---help---
	  Cause the compiler to optimize for POWER4/POWER5/PPC970 processors.
	  The resulting binary will not work on POWER3 or RS64 processors
	  when compiled with binutils 2.15 or later.

config POWER3
	bool
	depends on PPC64
	default y if !POWER4_ONLY

config POWER4
	depends on PPC64
	def_bool y

config TUNE_CELL
	bool "Optimize for Cell Broadband Engine"
	depends on PPC64
	help
	  Cause the compiler to optimize for the PPE of the Cell Broadband
	  Engine. This will make the code run considerably faster on Cell
	  but somewhat slower on other machines. This option only changes
	  the scheduling of instructions, not the selection of instructions
	  itself, so the resulting kernel will keep running on all other
	  machines. When building a kernel that is supposed to run only
	  on Cell, you should also select the POWER4_ONLY option.

config 6xx
	bool

# this is temp to handle compat with arch=ppc
config 8xx
	bool

# this is temp to handle compat with arch=ppc
config 83xx
	bool

# this is temp to handle compat with arch=ppc
config 85xx
	bool

config E500
	bool

config PPC_FPU
	bool
	default y if PPC64

config 4xx
	bool
	depends on 40x || 44x
	default y

config BOOKE
	bool
	depends on E200 || E500 || 44x
	default y

config FSL_BOOKE
	bool
	depends on E200 || E500
	default y

config PTE_64BIT
	bool
	depends on 44x || E500
	default y if 44x
	default y if E500 && PHYS_64BIT

config PHYS_64BIT
	bool 'Large physical address support' if E500
	depends on 44x || E500
	select RESOURCES_64BIT
	default y if 44x
	---help---
	  This option enables kernel support for larger than 32-bit physical
	  addresses.  This features is not be available on all e500 cores.

	  If in doubt, say N here.

config ALTIVEC
	bool "AltiVec Support"
	depends on CLASSIC32 || POWER4
	---help---
	  This option enables kernel support for the Altivec extensions to the
	  PowerPC processor. The kernel currently supports saving and restoring
	  altivec registers, and turning on the 'altivec enable' bit so user
	  processes can execute altivec instructions.

	  This option is only usefully if you have a processor that supports
	  altivec (G4, otherwise known as 74xx series), but does not have
	  any affect on a non-altivec cpu (it does, however add code to the
	  kernel).

	  If in doubt, say Y here.

config SPE
	bool "SPE Support"
	depends on E200 || E500
	default y
	---help---
	  This option enables kernel support for the Signal Processing
	  Extensions (SPE) to the PowerPC processor. The kernel currently
	  supports saving and restoring SPE registers, and turning on the
	  'spe enable' bit so user processes can execute SPE instructions.

	  This option is only useful if you have a processor that supports
	  SPE (e500, otherwise known as 85xx series), but does not have any
	  effect on a non-spe cpu (it does, however add code to the kernel).

	  If in doubt, say Y here.

config PPC_STD_MMU
	bool
	depends on 6xx || POWER3 || POWER4 || PPC64
	default y

config PPC_STD_MMU_32
	def_bool y
	depends on PPC_STD_MMU && PPC32

config PPC_MM_SLICES
	bool
	default y if HUGETLB_PAGE
	default n

config VIRT_CPU_ACCOUNTING
	bool "Deterministic task and CPU time accounting"
	depends on PPC64
	default y
	help
	  Select this option to enable more accurate task and CPU time
	  accounting.  This is done by reading a CPU counter on each
	  kernel entry and exit and on transitions within the kernel
	  between system, softirq and hardirq state, so there is a
	  small performance impact.  This also enables accounting of
	  stolen time on logically-partitioned systems running on
	  IBM POWER5-based machines.

	  If in doubt, say Y here.

config SMP
	depends on PPC_STD_MMU
	bool "Symmetric multi-processing support"
	---help---
	  This enables support for systems with more than one CPU. If you have
	  a system with only one CPU, say N. If you have a system with more
	  than one CPU, say Y.  Note that the kernel does not currently
	  support SMP machines with 603/603e/603ev or PPC750 ("G3") processors
	  since they have inadequate hardware support for multiprocessor
	  operation.

	  If you say N here, the kernel will run on single and multiprocessor
	  machines, but will use only one CPU of a multiprocessor machine. If
	  you say Y here, the kernel will run on single-processor machines.
	  On a single-processor machine, the kernel will run faster if you say
	  N here.

	  If you don't know what to do here, say N.

config NR_CPUS
	int "Maximum number of CPUs (2-128)"
	range 2 128
	depends on SMP
	default "32" if PPC64
	default "4"

config NOT_COHERENT_CACHE
	bool
	depends on 4xx || 8xx || E200
	default y

config CHECK_CACHE_COHERENCY
	bool

endmenu