xref: /openbmc/linux/arch/sh/mm/Kconfig (revision b0f3ae03)
1menu "Memory management options"
2
3config QUICKLIST
4	def_bool y
5
6config MMU
7        bool "Support for memory management hardware"
8	depends on !CPU_SH2
9	default y
10	help
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.
13
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.
17
18config PAGE_OFFSET
19	hex
20	default "0x80000000" if MMU && SUPERH32
21	default "0x20000000" if MMU && SUPERH64
22	default "0x00000000"
23
24config 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
30	range 11 64
31	default "14" if !MMU
32	default "11"
33	help
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
39	  increase this value.
40
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.
43
44	  The page size is not necessarily 4KB. Keep this in mind when
45	  choosing a value for this option.
46
47config MEMORY_START
48	hex "Physical memory start address"
49	default "0x08000000"
50	---help---
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.
54
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.
58
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.
62
63config MEMORY_SIZE
64	hex "Physical memory size"
65	default "0x04000000"
66	help
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
71	  configurable.
72
73# Physical addressing modes
74
75config 29BIT
76	def_bool !32BIT
77	depends on SUPERH32
78	select UNCACHED_MAPPING
79
80config 32BIT
81	bool
82	default y if CPU_SH5
83
84config PMB
85	bool "Support 32-bit physical addressing through PMB"
86	depends on MMU && EXPERIMENTAL && CPU_SH4A && !CPU_SH4AL_DSP
87	select 32BIT
88	select UNCACHED_MAPPING
89	help
90	  If you say Y here, physical addressing will be extended to
91	  32-bits through the SH-4A PMB. If this is not set, legacy
92	  29-bit physical addressing will be used.
93
94config PMB_LEGACY
95	bool "Support legacy boot mappings for PMB"
96	depends on PMB
97	select 32BIT
98	help
99	  If this option is enabled, fixed PMB mappings are inherited
100	  from the boot loader, and the kernel does not attempt dynamic
101	  management. This is the closest to legacy 29-bit physical mode,
102	  and allows systems to support up to 512MiB of system memory.
103
104config X2TLB
105	def_bool y
106	depends on (CPU_SHX2 || CPU_SHX3) && MMU
107
108config VSYSCALL
109	bool "Support vsyscall page"
110	depends on MMU && (CPU_SH3 || CPU_SH4)
111	default y
112	help
113	  This will enable support for the kernel mapping a vDSO page
114	  in process space, and subsequently handing down the entry point
115	  to the libc through the ELF auxiliary vector.
116
117	  From the kernel side this is used for the signal trampoline.
118	  For systems with an MMU that can afford to give up a page,
119	  (the default value) say Y.
120
121config NUMA
122	bool "Non Uniform Memory Access (NUMA) Support"
123	depends on MMU && SYS_SUPPORTS_NUMA && EXPERIMENTAL
124	default n
125	help
126	  Some SH systems have many various memories scattered around
127	  the address space, each with varying latencies. This enables
128	  support for these blocks by binding them to nodes and allowing
129	  memory policies to be used for prioritizing and controlling
130	  allocation behaviour.
131
132config NODES_SHIFT
133	int
134	default "3" if CPU_SUBTYPE_SHX3
135	default "1"
136	depends on NEED_MULTIPLE_NODES
137
138config ARCH_FLATMEM_ENABLE
139	def_bool y
140	depends on !NUMA
141
142config ARCH_SPARSEMEM_ENABLE
143	def_bool y
144	select SPARSEMEM_STATIC
145
146config ARCH_SPARSEMEM_DEFAULT
147	def_bool y
148
149config MAX_ACTIVE_REGIONS
150	int
151	default "6" if (CPU_SUBTYPE_SHX3 && SPARSEMEM)
152	default "2" if SPARSEMEM && (CPU_SUBTYPE_SH7722 || \
153		       CPU_SUBTYPE_SH7785)
154	default "1"
155
156config ARCH_POPULATES_NODE_MAP
157	def_bool y
158
159config ARCH_SELECT_MEMORY_MODEL
160	def_bool y
161
162config ARCH_ENABLE_MEMORY_HOTPLUG
163	def_bool y
164	depends on SPARSEMEM && MMU
165
166config ARCH_ENABLE_MEMORY_HOTREMOVE
167	def_bool y
168	depends on SPARSEMEM && MMU
169
170config ARCH_MEMORY_PROBE
171	def_bool y
172	depends on MEMORY_HOTPLUG
173
174config IOREMAP_FIXED
175       def_bool y
176       depends on X2TLB || SUPERH64
177
178config UNCACHED_MAPPING
179	bool
180
181choice
182	prompt "Kernel page size"
183	default PAGE_SIZE_4KB
184
185config PAGE_SIZE_4KB
186	bool "4kB"
187	help
188	  This is the default page size used by all SuperH CPUs.
189
190config PAGE_SIZE_8KB
191	bool "8kB"
192	depends on !MMU || X2TLB
193	help
194	  This enables 8kB pages as supported by SH-X2 and later MMUs.
195
196config PAGE_SIZE_16KB
197	bool "16kB"
198	depends on !MMU
199	help
200	  This enables 16kB pages on MMU-less SH systems.
201
202config PAGE_SIZE_64KB
203	bool "64kB"
204	depends on !MMU || CPU_SH4 || CPU_SH5
205	help
206	  This enables support for 64kB pages, possible on all SH-4
207	  CPUs and later.
208
209endchoice
210
211choice
212	prompt "HugeTLB page size"
213	depends on HUGETLB_PAGE
214	default HUGETLB_PAGE_SIZE_1MB if PAGE_SIZE_64KB
215	default HUGETLB_PAGE_SIZE_64K
216
217config HUGETLB_PAGE_SIZE_64K
218	bool "64kB"
219	depends on !PAGE_SIZE_64KB
220
221config HUGETLB_PAGE_SIZE_256K
222	bool "256kB"
223	depends on X2TLB
224
225config HUGETLB_PAGE_SIZE_1MB
226	bool "1MB"
227
228config HUGETLB_PAGE_SIZE_4MB
229	bool "4MB"
230	depends on X2TLB
231
232config HUGETLB_PAGE_SIZE_64MB
233	bool "64MB"
234	depends on X2TLB
235
236config HUGETLB_PAGE_SIZE_512MB
237	bool "512MB"
238	depends on CPU_SH5
239
240endchoice
241
242source "mm/Kconfig"
243
244config SCHED_MC
245	bool "Multi-core scheduler support"
246	depends on SMP
247	default y
248	help
249	  Multi-core scheduler support improves the CPU scheduler's decision
250	  making when dealing with multi-core CPU chips at a cost of slightly
251	  increased overhead in some places. If unsure say N here.
252
253endmenu
254
255menu "Cache configuration"
256
257config SH7705_CACHE_32KB
258	bool "Enable 32KB cache size for SH7705"
259	depends on CPU_SUBTYPE_SH7705
260	default y
261
262choice
263	prompt "Cache mode"
264	default CACHE_WRITEBACK if CPU_SH2A || CPU_SH3 || CPU_SH4 || CPU_SH5
265	default CACHE_WRITETHROUGH if (CPU_SH2 && !CPU_SH2A)
266
267config CACHE_WRITEBACK
268	bool "Write-back"
269
270config CACHE_WRITETHROUGH
271	bool "Write-through"
272	help
273	  Selecting this option will configure the caches in write-through
274	  mode, as opposed to the default write-back configuration.
275
276	  Since there's sill some aliasing issues on SH-4, this option will
277	  unfortunately still require the majority of flushing functions to
278	  be implemented to deal with aliasing.
279
280	  If unsure, say N.
281
282config CACHE_OFF
283	bool "Off"
284
285endchoice
286
287endmenu
288