xref: /openbmc/linux/arch/sh/mm/Kconfig (revision e190bfe5) 
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 X2TLB
95	def_bool y
96	depends on (CPU_SHX2 || CPU_SHX3) && MMU
97
98config VSYSCALL
99	bool "Support vsyscall page"
100	depends on MMU && (CPU_SH3 || CPU_SH4)
101	default y
102	help
103	  This will enable support for the kernel mapping a vDSO page
104	  in process space, and subsequently handing down the entry point
105	  to the libc through the ELF auxiliary vector.
106
107	  From the kernel side this is used for the signal trampoline.
108	  For systems with an MMU that can afford to give up a page,
109	  (the default value) say Y.
110
111config NUMA
112	bool "Non Uniform Memory Access (NUMA) Support"
113	depends on MMU && SYS_SUPPORTS_NUMA && EXPERIMENTAL
114	default n
115	help
116	  Some SH systems have many various memories scattered around
117	  the address space, each with varying latencies. This enables
118	  support for these blocks by binding them to nodes and allowing
119	  memory policies to be used for prioritizing and controlling
120	  allocation behaviour.
121
122config NODES_SHIFT
123	int
124	default "3" if CPU_SUBTYPE_SHX3
125	default "1"
126	depends on NEED_MULTIPLE_NODES
127
128config ARCH_FLATMEM_ENABLE
129	def_bool y
130	depends on !NUMA
131
132config ARCH_SPARSEMEM_ENABLE
133	def_bool y
134	select SPARSEMEM_STATIC
135
136config ARCH_SPARSEMEM_DEFAULT
137	def_bool y
138
139config MAX_ACTIVE_REGIONS
140	int
141	default "6" if (CPU_SUBTYPE_SHX3 && SPARSEMEM)
142	default "2" if SPARSEMEM && (CPU_SUBTYPE_SH7722 || \
143		       CPU_SUBTYPE_SH7785)
144	default "1"
145
146config ARCH_POPULATES_NODE_MAP
147	def_bool y
148
149config ARCH_SELECT_MEMORY_MODEL
150	def_bool y
151
152config ARCH_ENABLE_MEMORY_HOTPLUG
153	def_bool y
154	depends on SPARSEMEM && MMU
155
156config ARCH_ENABLE_MEMORY_HOTREMOVE
157	def_bool y
158	depends on SPARSEMEM && MMU
159
160config ARCH_MEMORY_PROBE
161	def_bool y
162	depends on MEMORY_HOTPLUG
163
164config IOREMAP_FIXED
165       def_bool y
166       depends on X2TLB || SUPERH64
167
168config UNCACHED_MAPPING
169	bool
170
171choice
172	prompt "Kernel page size"
173	default PAGE_SIZE_4KB
174
175config PAGE_SIZE_4KB
176	bool "4kB"
177	help
178	  This is the default page size used by all SuperH CPUs.
179
180config PAGE_SIZE_8KB
181	bool "8kB"
182	depends on !MMU || X2TLB
183	help
184	  This enables 8kB pages as supported by SH-X2 and later MMUs.
185
186config PAGE_SIZE_16KB
187	bool "16kB"
188	depends on !MMU
189	help
190	  This enables 16kB pages on MMU-less SH systems.
191
192config PAGE_SIZE_64KB
193	bool "64kB"
194	depends on !MMU || CPU_SH4 || CPU_SH5
195	help
196	  This enables support for 64kB pages, possible on all SH-4
197	  CPUs and later.
198
199endchoice
200
201choice
202	prompt "HugeTLB page size"
203	depends on HUGETLB_PAGE
204	default HUGETLB_PAGE_SIZE_1MB if PAGE_SIZE_64KB
205	default HUGETLB_PAGE_SIZE_64K
206
207config HUGETLB_PAGE_SIZE_64K
208	bool "64kB"
209	depends on !PAGE_SIZE_64KB
210
211config HUGETLB_PAGE_SIZE_256K
212	bool "256kB"
213	depends on X2TLB
214
215config HUGETLB_PAGE_SIZE_1MB
216	bool "1MB"
217
218config HUGETLB_PAGE_SIZE_4MB
219	bool "4MB"
220	depends on X2TLB
221
222config HUGETLB_PAGE_SIZE_64MB
223	bool "64MB"
224	depends on X2TLB
225
226config HUGETLB_PAGE_SIZE_512MB
227	bool "512MB"
228	depends on CPU_SH5
229
230endchoice
231
232source "mm/Kconfig"
233
234config SCHED_MC
235	bool "Multi-core scheduler support"
236	depends on SMP
237	default y
238	help
239	  Multi-core scheduler support improves the CPU scheduler's decision
240	  making when dealing with multi-core CPU chips at a cost of slightly
241	  increased overhead in some places. If unsure say N here.
242
243endmenu
244
245menu "Cache configuration"
246
247config SH7705_CACHE_32KB
248	bool "Enable 32KB cache size for SH7705"
249	depends on CPU_SUBTYPE_SH7705
250	default y
251
252choice
253	prompt "Cache mode"
254	default CACHE_WRITEBACK if CPU_SH2A || CPU_SH3 || CPU_SH4 || CPU_SH5
255	default CACHE_WRITETHROUGH if (CPU_SH2 && !CPU_SH2A)
256
257config CACHE_WRITEBACK
258	bool "Write-back"
259
260config CACHE_WRITETHROUGH
261	bool "Write-through"
262	help
263	  Selecting this option will configure the caches in write-through
264	  mode, as opposed to the default write-back configuration.
265
266	  Since there's sill some aliasing issues on SH-4, this option will
267	  unfortunately still require the majority of flushing functions to
268	  be implemented to deal with aliasing.
269
270	  If unsure, say N.
271
272config CACHE_OFF
273	bool "Off"
274
275endchoice
276
277endmenu
278