linux_kernel/arch/arc/Kconfig

#
# Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
#

config ARC
	def_bool y
	select ARCH_SUPPORTS_ATOMIC_RMW if ARC_HAS_LLSC
	select BUILDTIME_EXTABLE_SORT
	select COMMON_CLK
	select CLONE_BACKWARDS
	# ARC Busybox based initramfs absolutely relies on DEVTMPFS for /dev
	select DEVTMPFS if !INITRAMFS_SOURCE=""
	select GENERIC_ATOMIC64
	select GENERIC_CLOCKEVENTS
	select GENERIC_FIND_FIRST_BIT
	# for now, we don't need GENERIC_IRQ_PROBE, CONFIG_GENERIC_IRQ_CHIP
	select GENERIC_IRQ_SHOW
	select GENERIC_PENDING_IRQ if SMP
	select GENERIC_SMP_IDLE_THREAD
	select HAVE_ARCH_KGDB
	select HAVE_ARCH_TRACEHOOK
	select HAVE_FUTEX_CMPXCHG
	select HAVE_IOREMAP_PROT
	select HAVE_KPROBES
	select HAVE_KRETPROBES
	select HAVE_MEMBLOCK
	select HAVE_MOD_ARCH_SPECIFIC if ARC_DW2_UNWIND
	select HAVE_OPROFILE
	select HAVE_PERF_EVENTS
	select IRQ_DOMAIN
	select MODULES_USE_ELF_RELA
	select NO_BOOTMEM
	select OF
	select OF_EARLY_FLATTREE
	select PERF_USE_VMALLOC
	select HAVE_DEBUG_STACKOVERFLOW

config TRACE_IRQFLAGS_SUPPORT
	def_bool y

config LOCKDEP_SUPPORT
	def_bool y

config SCHED_OMIT_FRAME_POINTER
	def_bool y

config GENERIC_CSUM
	def_bool y

config RWSEM_GENERIC_SPINLOCK
	def_bool y

config ARCH_FLATMEM_ENABLE
	def_bool y

config MMU
	def_bool y

config NO_IOPORT_MAP
	def_bool y

config GENERIC_CALIBRATE_DELAY
	def_bool y

config GENERIC_HWEIGHT
	def_bool y

config STACKTRACE_SUPPORT
	def_bool y
	select STACKTRACE

config HAVE_LATENCYTOP_SUPPORT
	def_bool y

source "init/Kconfig"
source "kernel/Kconfig.freezer"

menu "ARC Architecture Configuration"

menu "ARC Platform/SoC/Board"

source "arch/arc/plat-sim/Kconfig"
source "arch/arc/plat-tb10x/Kconfig"
source "arch/arc/plat-axs10x/Kconfig"
#New platform adds here

endmenu

choice
	prompt "ARC Instruction Set"
	default ISA_ARCOMPACT

config ISA_ARCOMPACT
	bool "ARCompact ISA"
	help
	  The original ARC ISA of ARC600/700 cores

config ISA_ARCV2
	bool "ARC ISA v2"
	help
	  ISA for the Next Generation ARC-HS cores

endchoice

menu "ARC CPU Configuration"

choice
	prompt "ARC Core"
	default ARC_CPU_770 if ISA_ARCOMPACT
	default ARC_CPU_HS if ISA_ARCV2

if ISA_ARCOMPACT

config ARC_CPU_750D
	bool "ARC750D"
	select ARC_CANT_LLSC
	help
	  Support for ARC750 core

config ARC_CPU_770
	bool "ARC770"
	select ARC_HAS_SWAPE
	help
	  Support for ARC770 core introduced with Rel 4.10 (Summer 2011)
	  This core has a bunch of cool new features:
	  -MMU-v3: Variable Page Sz (4k, 8k, 16k), bigger J-TLB (128x4)
                   Shared Address Spaces (for sharing TLB entires in MMU)
	  -Caches: New Prog Model, Region Flush
	  -Insns: endian swap, load-locked/store-conditional, time-stamp-ctr

endif	#ISA_ARCOMPACT

config ARC_CPU_HS
	bool "ARC-HS"
	depends on ISA_ARCV2
	help
	  Support for ARC HS38x Cores based on ARCv2 ISA
	  The notable features are:
	    - SMP configurations of upto 4 core with coherency
	    - Optional L2 Cache and IO-Coherency
	    - Revised Interrupt Architecture (multiple priorites, reg banks,
	        auto stack switch, auto regfile save/restore)
	    - MMUv4 (PIPT dcache, Huge Pages)
	    - Instructions for
		* 64bit load/store: LDD, STD
		* Hardware assisted divide/remainder: DIV, REM
		* Function prologue/epilogue: ENTER_S, LEAVE_S
		* IRQ enable/disable: CLRI, SETI
		* pop count: FFS, FLS
		* SETcc, BMSKN, XBFU...

endchoice

config CPU_BIG_ENDIAN
	bool "Enable Big Endian Mode"
	default n
	help
	  Build kernel for Big Endian Mode of ARC CPU

config SMP
	bool "Symmetric Multi-Processing"
	default n
	select ARC_HAS_COH_CACHES if ISA_ARCV2
	select ARC_MCIP if ISA_ARCV2
	help
	  This enables support for systems with more than one CPU.

if SMP

config ARC_HAS_COH_CACHES
	def_bool n

config ARC_HAS_REENTRANT_IRQ_LV2
	def_bool n

config ARC_MCIP
	bool "ARConnect Multicore IP (MCIP) Support "
	depends on ISA_ARCV2
	help
	  This IP block enables SMP in ARC-HS38 cores.
	  It provides for cross-core interrupts, multi-core debug
	  hardware semaphores, shared memory,....

config NR_CPUS
	int "Maximum number of CPUs (2-4096)"
	range 2 4096
	default "4"

endif	#SMP

menuconfig ARC_CACHE
	bool "Enable Cache Support"
	default y
	# if SMP, cache enabled ONLY if ARC implementation has cache coherency
	depends on !SMP || ARC_HAS_COH_CACHES

if ARC_CACHE

config ARC_CACHE_LINE_SHIFT
	int "Cache Line Length (as power of 2)"
	range 5 7
	default "6"
	help
	  Starting with ARC700 4.9, Cache line length is configurable,
	  This option specifies "N", with Line-len = 2 power N
	  So line lengths of 32, 64, 128 are specified by 5,6,7, respectively
	  Linux only supports same line lengths for I and D caches.

config ARC_HAS_ICACHE
	bool "Use Instruction Cache"
	default y

config ARC_HAS_DCACHE
	bool "Use Data Cache"
	default y

config ARC_CACHE_PAGES
	bool "Per Page Cache Control"
	default y
	depends on ARC_HAS_ICACHE || ARC_HAS_DCACHE
	help
	  This can be used to over-ride the global I/D Cache Enable on a
	  per-page basis (but only for pages accessed via MMU such as
	  Kernel Virtual address or User Virtual Address)
	  TLB entries have a per-page Cache Enable Bit.
	  Note that Global I/D ENABLE + Per Page DISABLE works but corollary
	  Global DISABLE + Per Page ENABLE won't work

config ARC_CACHE_VIPT_ALIASING
	bool "Support VIPT Aliasing D$"
	depends on ARC_HAS_DCACHE && ISA_ARCOMPACT
	default n

endif	#ARC_CACHE

config ARC_HAS_ICCM
	bool "Use ICCM"
	help
	  Single Cycle RAMS to store Fast Path Code
	default n

config ARC_ICCM_SZ
	int "ICCM Size in KB"
	default "64"
	depends on ARC_HAS_ICCM

config ARC_HAS_DCCM
	bool "Use DCCM"
	help
	  Single Cycle RAMS to store Fast Path Data
	default n

config ARC_DCCM_SZ
	int "DCCM Size in KB"
	default "64"
	depends on ARC_HAS_DCCM

config ARC_DCCM_BASE
	hex "DCCM map address"
	default "0xA0000000"
	depends on ARC_HAS_DCCM

config ARC_HAS_HW_MPY
	bool "Use Hardware Multiplier (Normal or Faster XMAC)"
	default y
	help
	  Influences how gcc generates code for MPY operations.
	  If enabled, MPYxx insns are generated, provided by Standard/XMAC
	  Multipler. Otherwise software multipy lib is used

choice
	prompt "MMU Version"
	default ARC_MMU_V3 if ARC_CPU_770
	default ARC_MMU_V2 if ARC_CPU_750D
	default ARC_MMU_V4 if ARC_CPU_HS

config ARC_MMU_V1
	bool "MMU v1"
	help
	  Orig ARC700 MMU

config ARC_MMU_V2
	bool "MMU v2"
	help
	  Fixed the deficiency of v1 - possible thrashing in memcpy sceanrio
	  when 2 D-TLB and 1 I-TLB entries index into same 2way set.

config ARC_MMU_V3
	bool "MMU v3"
	depends on ARC_CPU_770
	help
	  Introduced with ARC700 4.10: New Features
	  Variable Page size (1k-16k), var JTLB size 128 x (2 or 4)
	  Shared Address Spaces (SASID)

config ARC_MMU_V4
	bool "MMU v4"
	depends on ISA_ARCV2

endchoice


choice
	prompt "MMU Page Size"
	default ARC_PAGE_SIZE_8K

config ARC_PAGE_SIZE_8K
	bool "8KB"
	help
	  Choose between 8k vs 16k

config ARC_PAGE_SIZE_16K
	bool "16KB"
	depends on ARC_MMU_V3 || ARC_MMU_V4

config ARC_PAGE_SIZE_4K
	bool "4KB"
	depends on ARC_MMU_V3 || ARC_MMU_V4

endchoice

if ISA_ARCOMPACT

config ARC_COMPACT_IRQ_LEVELS
	bool "ARCompact IRQ Priorities: High(2)/Low(1)"
	default n
	# Timer HAS to be high priority, for any other high priority config
	select ARC_IRQ3_LV2
	# if SMP, LV2 enabled ONLY if ARC implementation has LV2 re-entrancy
	depends on !SMP || ARC_HAS_REENTRANT_IRQ_LV2

if ARC_COMPACT_IRQ_LEVELS

config ARC_IRQ3_LV2
	bool

config ARC_IRQ5_LV2
	bool

config ARC_IRQ6_LV2
	bool

endif	#ARC_COMPACT_IRQ_LEVELS

config ARC_FPU_SAVE_RESTORE
	bool "Enable FPU state persistence across context switch"
	default n
	help
	  Double Precision Floating Point unit had dedictaed regs which
	  need to be saved/restored across context-switch.
	  Note that ARC FPU is overly simplistic, unlike say x86, which has
	  hardware pieces to allow software to conditionally save/restore,
	  based on actual usage of FPU by a task. Thus our implemn does
	  this for all tasks in system.

endif	#ISA_ARCOMPACT

config ARC_CANT_LLSC
	def_bool n

config ARC_HAS_LLSC
	bool "Insn: LLOCK/SCOND (efficient atomic ops)"
	default y
	depends on !ARC_CANT_LLSC

config ARC_STAR_9000923308
	bool "Workaround for llock/scond livelock"
	default y
	depends on ISA_ARCV2 && SMP && ARC_HAS_LLSC

config ARC_HAS_SWAPE
	bool "Insn: SWAPE (endian-swap)"
	default y

if ISA_ARCV2

config ARC_HAS_LL64
	bool "Insn: 64bit LDD/STD"
	help
	  Enable gcc to generate 64-bit load/store instructions
	  ISA mandates even/odd registers to allow encoding of two
	  dest operands with 2 possible source operands.
	default y

config ARC_HAS_DIV_REM
	bool "Insn: div, divu, rem, remu"
	default y

config ARC_HAS_RTC
	bool "Local 64-bit r/o cycle counter"
	default n
	depends on !SMP

config ARC_HAS_GRTC
	bool "SMP synchronized 64-bit cycle counter"
	default y
	depends on SMP

config ARC_NUMBER_OF_INTERRUPTS
	int "Number of interrupts"
	range 8 240
	default 32
	help
	  This defines the number of interrupts on the ARCv2HS core.
	  It affects the size of vector table.
	  The initial 8 IRQs are fixed (Timer, ICI etc) and although configurable
	  in hardware, it keep things simple for Linux to assume they are always
	  present.

endif	# ISA_ARCV2

endmenu   # "ARC CPU Configuration"

config LINUX_LINK_BASE
	hex "Linux Link Address"
	default "0x80000000"
	help
	  ARC700 divides the 32 bit phy address space into two equal halves
	  -Lower 2G (0 - 0x7FFF_FFFF ) is user virtual, translated by MMU
	  -Upper 2G (0x8000_0000 onwards) is untranslated, for kernel
	  Typically Linux kernel is linked at the start of untransalted addr,
	  hence the default value of 0x8zs.
	  However some customers have peripherals mapped at this addr, so
	  Linux needs to be scooted a bit.
	  If you don't know what the above means, leave this setting alone.

config ARC_CURR_IN_REG
	bool "Dedicate Register r25 for current_task pointer"
	default y
	help
	  This reserved Register R25 to point to Current Task in
	  kernel mode. This saves memory access for each such access


config ARC_EMUL_UNALIGNED
	bool "Emulate unaligned memory access (userspace only)"
	default N
	select SYSCTL_ARCH_UNALIGN_NO_WARN
	select SYSCTL_ARCH_UNALIGN_ALLOW
	depends on ISA_ARCOMPACT
	help
	  This enables misaligned 16 & 32 bit memory access from user space.
	  Use ONLY-IF-ABS-NECESSARY as it will be very slow and also can hide
	  potential bugs in code

config HZ
	int "Timer Frequency"
	default 100

config ARC_METAWARE_HLINK
	bool "Support for Metaware debugger assisted Host access"
	default n
	help
	  This options allows a Linux userland apps to directly access
	  host file system (open/creat/read/write etc) with help from
	  Metaware Debugger. This can come in handy for Linux-host communication
	  when there is no real usable peripheral such as EMAC.

menuconfig ARC_DBG
	bool "ARC debugging"
	default y

if ARC_DBG

config ARC_DW2_UNWIND
	bool "Enable DWARF specific kernel stack unwind"
	default y
	select KALLSYMS
	help
	  Compiles the kernel with DWARF unwind information and can be used
	  to get stack backtraces.

	  If you say Y here the resulting kernel image will be slightly larger
	  but not slower, and it will give very useful debugging information.
	  If you don't debug the kernel, you can say N, but we may not be able
	  to solve problems without frame unwind information

config ARC_DBG_TLB_PARANOIA
	bool "Paranoia Checks in Low Level TLB Handlers"
	default n

config ARC_DBG_TLB_MISS_COUNT
	bool "Profile TLB Misses"
	default n
	select DEBUG_FS
	help
	  Counts number of I and D TLB Misses and exports them via Debugfs
	  The counters can be cleared via Debugfs as well

if SMP

config ARC_IPI_DBG
	bool "Debug Inter Core interrupts"
	default n

endif

endif

config ARC_UBOOT_SUPPORT
	bool "Support uboot arg Handling"
	default n
	help
	  ARC Linux by default checks for uboot provided args as pointers to
	  external cmdline or DTB. This however breaks in absence of uboot,
	  when booting from Metaware debugger directly, as the registers are
	  not zeroed out on reset by mdb and/or ARCv2 based cores. The bogus
	  registers look like uboot args to kernel which then chokes.
	  So only enable the uboot arg checking/processing if users are sure
	  of uboot being in play.

config ARC_BUILTIN_DTB_NAME
	string "Built in DTB"
	help
	  Set the name of the DTB to embed in the vmlinux binary
	  Leaving it blank selects the minimal "skeleton" dtb

source "kernel/Kconfig.preempt"

menu "Executable file formats"
source "fs/Kconfig.binfmt"
endmenu

endmenu	 # "ARC Architecture Configuration"

source "mm/Kconfig"
source "net/Kconfig"
source "drivers/Kconfig"
source "fs/Kconfig"
source "arch/arc/Kconfig.debug"
source "security/Kconfig"
source "crypto/Kconfig"
source "lib/Kconfig"
source "kernel/power/Kconfig"