1 menu "Memory management options"
7 bool "Support for memory management hardware"
11 Some SH processors (such as SH-2/SH-2A) lack an MMU. In order to
12 boot on these systems, this option must not be set.
14 On other systems (such as the SH-3 and 4) where an MMU exists,
15 turning this off will boot the kernel on these machines with the
16 MMU implicitly switched off.
20 default "0x80000000" if MMU && SUPERH32
21 default "0x20000000" if MMU && SUPERH64
24 config FORCE_MAX_ZONEORDER
25 int "Maximum zone order"
26 range 9 64 if PAGE_SIZE_16KB
27 default "9" if PAGE_SIZE_16KB
28 range 7 64 if PAGE_SIZE_64KB
29 default "7" if PAGE_SIZE_64KB
34 The kernel memory allocator divides physically contiguous memory
35 blocks into "zones", where each zone is a power of two number of
36 pages. This option selects the largest power of two that the kernel
37 keeps in the memory allocator. If you need to allocate very large
38 blocks of physically contiguous memory, then you may need to
41 This config option is actually maximum order plus one. For example,
42 a value of 11 means that the largest free memory block is 2^10 pages.
44 The page size is not necessarily 4KB. Keep this in mind when
45 choosing a value for this option.
48 hex "Physical memory start address"
51 Computers built with Hitachi SuperH processors always
52 map the ROM starting at address zero. But the processor
53 does not specify the range that RAM takes.
55 The physical memory (RAM) start address will be automatically
56 set to 08000000. Other platforms, such as the Solution Engine
57 boards typically map RAM at 0C000000.
59 Tweak this only when porting to a new machine which does not
60 already have a defconfig. Changing it from the known correct
61 value on any of the known systems will only lead to disaster.
64 hex "Physical memory size"
67 This sets the default memory size assumed by your SH kernel. It can
68 be overridden as normal by the 'mem=' argument on the kernel command
69 line. If unsure, consult your board specifications or just leave it
70 as 0x04000000 which was the default value before this became
73 # Physical addressing modes
84 bool "Support 32-bit physical addressing through PMB"
85 depends on MMU && EXPERIMENTAL && (CPU_SUBTYPE_SH7780 || CPU_SUBTYPE_SH7785)
89 If you say Y here, physical addressing will be extended to
90 32-bits through the SH-4A PMB. If this is not set, legacy
91 29-bit physical addressing will be used.
94 prompt "PMB handling type"
100 depends on MMU && EXPERIMENTAL && (CPU_SUBTYPE_SH7780 || CPU_SUBTYPE_SH7785)
103 If you say Y here, physical addressing will be extended to
104 32-bits through the SH-4A PMB. If this is not set, legacy
105 29-bit physical addressing will be used.
109 depends on MMU && EXPERIMENTAL && (CPU_SUBTYPE_SH7780 || \
113 If this option is enabled, fixed PMB mappings are inherited
114 from the boot loader, and the kernel does not attempt dynamic
115 management. This is the closest to legacy 29-bit physical mode,
116 and allows systems to support up to 512MiB of system memory.
121 bool "Enable extended TLB mode"
122 depends on (CPU_SHX2 || CPU_SHX3) && MMU && EXPERIMENTAL
124 Selecting this option will enable the extended mode of the SH-X2
125 TLB. For legacy SH-X behaviour and interoperability, say N. For
126 all of the fun new features and a willingless to submit bug reports,
130 bool "Support vsyscall page"
131 depends on MMU && (CPU_SH3 || CPU_SH4)
134 This will enable support for the kernel mapping a vDSO page
135 in process space, and subsequently handing down the entry point
136 to the libc through the ELF auxiliary vector.
138 From the kernel side this is used for the signal trampoline.
139 For systems with an MMU that can afford to give up a page,
140 (the default value) say Y.
143 bool "Non Uniform Memory Access (NUMA) Support"
144 depends on MMU && SYS_SUPPORTS_NUMA && EXPERIMENTAL
147 Some SH systems have many various memories scattered around
148 the address space, each with varying latencies. This enables
149 support for these blocks by binding them to nodes and allowing
150 memory policies to be used for prioritizing and controlling
151 allocation behaviour.
155 default "3" if CPU_SUBTYPE_SHX3
157 depends on NEED_MULTIPLE_NODES
159 config ARCH_FLATMEM_ENABLE
163 config ARCH_SPARSEMEM_ENABLE
165 select SPARSEMEM_STATIC
167 config ARCH_SPARSEMEM_DEFAULT
170 config MAX_ACTIVE_REGIONS
172 default "6" if (CPU_SUBTYPE_SHX3 && SPARSEMEM)
173 default "2" if SPARSEMEM && (CPU_SUBTYPE_SH7722 || \
177 config ARCH_POPULATES_NODE_MAP
180 config ARCH_SELECT_MEMORY_MODEL
183 config ARCH_ENABLE_MEMORY_HOTPLUG
185 depends on SPARSEMEM && MMU
187 config ARCH_ENABLE_MEMORY_HOTREMOVE
189 depends on SPARSEMEM && MMU
191 config ARCH_MEMORY_PROBE
193 depends on MEMORY_HOTPLUG
196 prompt "Kernel page size"
197 default PAGE_SIZE_8KB if X2TLB
198 default PAGE_SIZE_4KB
202 depends on !MMU || !X2TLB
204 This is the default page size used by all SuperH CPUs.
208 depends on !MMU || X2TLB
210 This enables 8kB pages as supported by SH-X2 and later MMUs.
212 config PAGE_SIZE_16KB
216 This enables 16kB pages on MMU-less SH systems.
218 config PAGE_SIZE_64KB
220 depends on !MMU || CPU_SH4 || CPU_SH5
222 This enables support for 64kB pages, possible on all SH-4
228 prompt "HugeTLB page size"
229 depends on HUGETLB_PAGE && (CPU_SH4 || CPU_SH5) && MMU
230 default HUGETLB_PAGE_SIZE_1MB if PAGE_SIZE_64KB
231 default HUGETLB_PAGE_SIZE_64K
233 config HUGETLB_PAGE_SIZE_64K
235 depends on !PAGE_SIZE_64KB
237 config HUGETLB_PAGE_SIZE_256K
241 config HUGETLB_PAGE_SIZE_1MB
244 config HUGETLB_PAGE_SIZE_4MB
248 config HUGETLB_PAGE_SIZE_64MB
252 config HUGETLB_PAGE_SIZE_512MB
262 menu "Cache configuration"
264 config SH7705_CACHE_32KB
265 bool "Enable 32KB cache size for SH7705"
266 depends on CPU_SUBTYPE_SH7705
271 default CACHE_WRITEBACK if CPU_SH2A || CPU_SH3 || CPU_SH4 || CPU_SH5
272 default CACHE_WRITETHROUGH if (CPU_SH2 && !CPU_SH2A)
274 config CACHE_WRITEBACK
277 config CACHE_WRITETHROUGH
280 Selecting this option will configure the caches in write-through
281 mode, as opposed to the default write-back configuration.
283 Since there's sill some aliasing issues on SH-4, this option will
284 unfortunately still require the majority of flushing functions to
285 be implemented to deal with aliasing.