ARC: Build system: Makefiles, Kconfig, Linker script
Arnd in his review pointed out that arch Kconfig organisation has several
deficiencies:
* Build time entries for things which can be runtime extracted from DT
(e.g. SDRAM size, core clk frequency..)
* Not multi-platform-image-build friendly (choice .. endchoice constructs)
* cpu variants support (750/770) is exclusive.
The first 2 have been fixed in subsequent patches.
Due to the nature of the 750 and 770, it is not possible to build for
both together, w/o special runtime glue code which would hurt
performance.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
new file mode 100644
index 0000000..b0b09ae
--- /dev/null
+++ b/arch/arc/Kconfig
@@ -0,0 +1,328 @@
+#
+# 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_NO_VIRT_TO_BUS
+ # 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_GENERIC_HARDIRQS
+ select MODULES_USE_ELF_RELA
+
+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
+ def_bool y
+
+config GENERIC_CALIBRATE_DELAY
+ def_bool y
+
+config GENERIC_HWEIGHT
+ def_bool y
+
+config BINFMT_ELF
+ def_bool y
+
+config HAVE_LATENCYTOP_SUPPORT
+ def_bool y
+
+config NO_DMA
+ def_bool n
+
+source "init/Kconfig"
+source "kernel/Kconfig.freezer"
+
+menu "ARC Architecture Configuration"
+
+choice
+ prompt "ARC Platform"
+ default ARC_PLAT_FPGA_LEGACY
+
+config ARC_PLAT_FPGA_LEGACY
+ bool "\"Legacy\" ARC FPGA dev platform"
+ help
+ Support for ARC development platforms, provided by Synopsys.
+ These are based on FPGA or ISS. e.g.
+ - ARCAngel4
+ - ML509
+ - MetaWare ISS
+
+#New platform adds here
+endchoice
+
+menu "ARC CPU Configuration"
+
+choice
+ prompt "ARC Core"
+ default ARC_CPU_770
+
+config ARC_CPU_750D
+ bool "ARC750D"
+ help
+ Support for ARC750 core
+
+config ARC_CPU_770
+ bool "ARC770"
+ select ARC_CPU_REL_4_10
+ 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
+
+endchoice
+
+config CPU_BIG_ENDIAN
+ bool "Enable Big Endian Mode"
+ default n
+ help
+ Build kernel for Big Endian Mode of ARC CPU
+
+menuconfig ARC_CACHE
+ bool "Enable Cache Support"
+ default y
+
+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
+
+endif #ARC_CACHE
+
+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 "ARC700 MMU Version"
+ default ARC_MMU_V3 if ARC_CPU_770
+ default ARC_MMU_V2 if ARC_CPU_750D
+
+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)
+
+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
+
+config ARC_PAGE_SIZE_4K
+ bool "4KB"
+ depends on ARC_MMU_V3
+
+endchoice
+
+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.
+
+menuconfig ARC_CPU_REL_4_10
+ bool "Enable support for Rel 4.10 features"
+ default n
+ help
+ -ARC770 (and dependent features) enabled
+ -ARC750 also shares some of the new features with 770
+
+config ARC_HAS_LLSC
+ bool "Insn: LLOCK/SCOND (efficient atomic ops)"
+ default y
+ depends on ARC_CPU_770
+ # if SMP, enable LLSC ONLY if ARC implementation has coherent atomics
+ depends on !SMP || ARC_HAS_COH_LLSC
+
+config ARC_HAS_SWAPE
+ bool "Insn: SWAPE (endian-swap)"
+ default y
+ depends on ARC_CPU_REL_4_10
+
+config ARC_HAS_RTSC
+ bool "Insn: RTSC (64-bit r/o cycle counter)"
+ default y
+ depends on ARC_CPU_REL_4_10
+
+endmenu # "ARC CPU Configuration"
+
+menu "Platform Board Configuration"
+
+source "arch/arc/plat-arcfpga/Kconfig"
+
+#New platform adds here
+
+config ARC_PLAT_CLK
+ int "Clk speed in Hz"
+ default "80000000"
+
+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_PLAT_SDRAM_SIZE
+ hex "SD RAM Size"
+ default "0x10000000"
+ help
+ Implies the amount of SDRAM/DRAM Linux is going to claim/own.
+ The actual memory itself could be larger than this number. But for
+ all software purposes, this is the amt of memory.
+
+endmenu # "Platform Board Configuration"
+
+config ARC_STACK_NONEXEC
+ bool "Make stack non-executable"
+ default n
+ help
+ To disable the execute permissions of stack/heap of processes
+ which are enabled by default.
+
+config HZ
+ int "Timer Frequency"
+ default 100
+
+menuconfig ARC_DBG
+ bool "ARC debugging"
+ default y
+
+config ARC_DBG_TLB_PARANOIA
+ bool "Paranoia Checks in Low Level TLB Handlers"
+ depends on ARC_DBG
+ default n
+
+config ARC_DBG_TLB_MISS_COUNT
+ bool "Profile TLB Misses"
+ default n
+ select DEBUG_FS
+ depends on ARC_DBG
+ help
+ Counts number of I and D TLB Misses and exports them via Debugfs
+ The counters can be cleared via Debugfs as well
+
+config CMDLINE
+ string "Kernel command line to built-in"
+ default "print-fatal-signals=1"
+ help
+ The default command line which will be appended to the optional
+ u-boot provided command line (see below)
+
+config CMDLINE_UBOOT
+ bool "Support U-boot kernel command line passing"
+ default n
+ help
+ If you are using U-boot (www.denx.de) and wish to pass the kernel
+ command line from the U-boot environment to the Linux kernel then
+ switch this option on.
+ ARC U-boot will setup the cmdline in RAM/flash and set r2 to point
+ to it. kernel startup code will copy the string into cmdline buffer
+ and also append CONFIG_CMDLINE.
+
+source "kernel/Kconfig.preempt"
+
+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"