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+# SPDX-License-Identifier: GPL-2.0
+menu "Memory management options"
+
+config MMU
+ bool "Support for memory management hardware"
+ depends on !CPU_SH2
+ default y
+ help
+ Some SH processors (such as SH-2/SH-2A) lack an MMU. In order to
+ boot on these systems, this option must not be set.
+
+ On other systems (such as the SH-3 and 4) where an MMU exists,
+ turning this off will boot the kernel on these machines with the
+ MMU implicitly switched off.
+
+config PAGE_OFFSET
+ hex
+ default "0x80000000" if MMU
+ default "0x00000000"
+
+config ARCH_FORCE_MAX_ORDER
+ int "Maximum zone order"
+ range 9 64 if PAGE_SIZE_16KB
+ default "9" if PAGE_SIZE_16KB
+ range 7 64 if PAGE_SIZE_64KB
+ default "7" if PAGE_SIZE_64KB
+ range 11 64
+ default "14" if !MMU
+ default "11"
+ help
+ The kernel memory allocator divides physically contiguous memory
+ blocks into "zones", where each zone is a power of two number of
+ pages. This option selects the largest power of two that the kernel
+ keeps in the memory allocator. If you need to allocate very large
+ blocks of physically contiguous memory, then you may need to
+ increase this value.
+
+ This config option is actually maximum order plus one. For example,
+ a value of 11 means that the largest free memory block is 2^10 pages.
+
+ The page size is not necessarily 4KB. Keep this in mind when
+ choosing a value for this option.
+
+config MEMORY_START
+ hex "Physical memory start address"
+ default "0x08000000"
+ help
+ Computers built with Hitachi SuperH processors always
+ map the ROM starting at address zero. But the processor
+ does not specify the range that RAM takes.
+
+ The physical memory (RAM) start address will be automatically
+ set to 08000000. Other platforms, such as the Solution Engine
+ boards typically map RAM at 0C000000.
+
+ Tweak this only when porting to a new machine which does not
+ already have a defconfig. Changing it from the known correct
+ value on any of the known systems will only lead to disaster.
+
+config MEMORY_SIZE
+ hex "Physical memory size"
+ default "0x04000000"
+ help
+ This sets the default memory size assumed by your SH kernel. It can
+ be overridden as normal by the 'mem=' argument on the kernel command
+ line. If unsure, consult your board specifications or just leave it
+ as 0x04000000 which was the default value before this became
+ configurable.
+
+# Physical addressing modes
+
+config 29BIT
+ def_bool !32BIT
+ select UNCACHED_MAPPING
+
+config 32BIT
+ bool
+ default !MMU
+
+config PMB
+ bool "Support 32-bit physical addressing through PMB"
+ depends on MMU && CPU_SH4A && !CPU_SH4AL_DSP
+ select 32BIT
+ select UNCACHED_MAPPING
+ help
+ If you say Y here, physical addressing will be extended to
+ 32-bits through the SH-4A PMB. If this is not set, legacy
+ 29-bit physical addressing will be used.
+
+config X2TLB
+ def_bool y
+ depends on (CPU_SHX2 || CPU_SHX3) && MMU
+
+config VSYSCALL
+ bool "Support vsyscall page"
+ depends on MMU && (CPU_SH3 || CPU_SH4)
+ default y
+ help
+ This will enable support for the kernel mapping a vDSO page
+ in process space, and subsequently handing down the entry point
+ to the libc through the ELF auxiliary vector.
+
+ From the kernel side this is used for the signal trampoline.
+ For systems with an MMU that can afford to give up a page,
+ (the default value) say Y.
+
+config NUMA
+ bool "Non-Uniform Memory Access (NUMA) Support"
+ depends on MMU && SYS_SUPPORTS_NUMA
+ select ARCH_WANT_NUMA_VARIABLE_LOCALITY
+ default n
+ help
+ Some SH systems have many various memories scattered around
+ the address space, each with varying latencies. This enables
+ support for these blocks by binding them to nodes and allowing
+ memory policies to be used for prioritizing and controlling
+ allocation behaviour.
+
+config NODES_SHIFT
+ int
+ default "3" if CPU_SUBTYPE_SHX3
+ default "1"
+ depends on NUMA
+
+config ARCH_FLATMEM_ENABLE
+ def_bool y
+ depends on !NUMA
+
+config ARCH_SPARSEMEM_ENABLE
+ def_bool y
+ select SPARSEMEM_STATIC
+
+config ARCH_SPARSEMEM_DEFAULT
+ def_bool y
+
+config ARCH_SELECT_MEMORY_MODEL
+ def_bool y
+
+config ARCH_MEMORY_PROBE
+ def_bool y
+ depends on MEMORY_HOTPLUG
+
+config IOREMAP_FIXED
+ def_bool y
+ depends on X2TLB
+
+config UNCACHED_MAPPING
+ bool
+
+config HAVE_SRAM_POOL
+ bool
+ select GENERIC_ALLOCATOR
+
+choice
+ prompt "Kernel page size"
+ default PAGE_SIZE_4KB
+
+config PAGE_SIZE_4KB
+ bool "4kB"
+ help
+ This is the default page size used by all SuperH CPUs.
+
+config PAGE_SIZE_8KB
+ bool "8kB"
+ depends on !MMU || X2TLB
+ help
+ This enables 8kB pages as supported by SH-X2 and later MMUs.
+
+config PAGE_SIZE_16KB
+ bool "16kB"
+ depends on !MMU
+ help
+ This enables 16kB pages on MMU-less SH systems.
+
+config PAGE_SIZE_64KB
+ bool "64kB"
+ depends on !MMU || CPU_SH4
+ help
+ This enables support for 64kB pages, possible on all SH-4
+ CPUs and later.
+
+endchoice
+
+choice
+ prompt "HugeTLB page size"
+ depends on HUGETLB_PAGE
+ default HUGETLB_PAGE_SIZE_1MB if PAGE_SIZE_64KB
+ default HUGETLB_PAGE_SIZE_64K
+
+config HUGETLB_PAGE_SIZE_64K
+ bool "64kB"
+ depends on !PAGE_SIZE_64KB
+
+config HUGETLB_PAGE_SIZE_256K
+ bool "256kB"
+ depends on X2TLB
+
+config HUGETLB_PAGE_SIZE_1MB
+ bool "1MB"
+
+config HUGETLB_PAGE_SIZE_4MB
+ bool "4MB"
+ depends on X2TLB
+
+config HUGETLB_PAGE_SIZE_64MB
+ bool "64MB"
+ depends on X2TLB
+
+endchoice
+
+config SCHED_MC
+ bool "Multi-core scheduler support"
+ depends on SMP
+ default y
+ help
+ Multi-core scheduler support improves the CPU scheduler's decision
+ making when dealing with multi-core CPU chips at a cost of slightly
+ increased overhead in some places. If unsure say N here.
+
+endmenu
+
+menu "Cache configuration"
+
+config SH7705_CACHE_32KB
+ bool "Enable 32KB cache size for SH7705"
+ depends on CPU_SUBTYPE_SH7705
+ default y
+
+choice
+ prompt "Cache mode"
+ default CACHE_WRITEBACK if CPU_SH2A || CPU_SH3 || CPU_SH4
+ default CACHE_WRITETHROUGH if (CPU_SH2 && !CPU_SH2A)
+
+config CACHE_WRITEBACK
+ bool "Write-back"
+
+config CACHE_WRITETHROUGH
+ bool "Write-through"
+ help
+ Selecting this option will configure the caches in write-through
+ mode, as opposed to the default write-back configuration.
+
+ Since there's sill some aliasing issues on SH-4, this option will
+ unfortunately still require the majority of flushing functions to
+ be implemented to deal with aliasing.
+
+ If unsure, say N.
+
+config CACHE_OFF
+ bool "Off"
+
+endchoice
+
+endmenu