xref: /openbmc/linux/arch/sh/mm/Kconfig (revision 93dc544c) 
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 MEMORY_START
25	hex "Physical memory start address"
26	default "0x08000000"
27	---help---
28	  Computers built with Hitachi SuperH processors always
29	  map the ROM starting at address zero.  But the processor
30	  does not specify the range that RAM takes.
31
32	  The physical memory (RAM) start address will be automatically
33	  set to 08000000. Other platforms, such as the Solution Engine
34	  boards typically map RAM at 0C000000.
35
36	  Tweak this only when porting to a new machine which does not
37	  already have a defconfig. Changing it from the known correct
38	  value on any of the known systems will only lead to disaster.
39
40config MEMORY_SIZE
41	hex "Physical memory size"
42	default "0x04000000"
43	help
44	  This sets the default memory size assumed by your SH kernel. It can
45	  be overridden as normal by the 'mem=' argument on the kernel command
46	  line. If unsure, consult your board specifications or just leave it
47	  as 0x04000000 which was the default value before this became
48	  configurable.
49
50# Physical addressing modes
51
52config 29BIT
53	def_bool !32BIT
54	depends on SUPERH32
55
56config 32BIT
57	bool
58	default y if CPU_SH5
59
60config PMB
61	bool "Support 32-bit physical addressing through PMB"
62	depends on MMU && EXPERIMENTAL && (CPU_SUBTYPE_SH7780 || CPU_SUBTYPE_SH7785)
63	select 32BIT
64	default y
65	help
66	  If you say Y here, physical addressing will be extended to
67	  32-bits through the SH-4A PMB. If this is not set, legacy
68	  29-bit physical addressing will be used.
69
70config X2TLB
71	bool "Enable extended TLB mode"
72	depends on (CPU_SHX2 || CPU_SHX3) && MMU && EXPERIMENTAL
73	help
74	  Selecting this option will enable the extended mode of the SH-X2
75	  TLB. For legacy SH-X behaviour and interoperability, say N. For
76	  all of the fun new features and a willingless to submit bug reports,
77	  say Y.
78
79config VSYSCALL
80	bool "Support vsyscall page"
81	depends on MMU && (CPU_SH3 || CPU_SH4)
82	default y
83	help
84	  This will enable support for the kernel mapping a vDSO page
85	  in process space, and subsequently handing down the entry point
86	  to the libc through the ELF auxiliary vector.
87
88	  From the kernel side this is used for the signal trampoline.
89	  For systems with an MMU that can afford to give up a page,
90	  (the default value) say Y.
91
92config NUMA
93	bool "Non Uniform Memory Access (NUMA) Support"
94	depends on MMU && SYS_SUPPORTS_NUMA && EXPERIMENTAL
95	default n
96	help
97	  Some SH systems have many various memories scattered around
98	  the address space, each with varying latencies. This enables
99	  support for these blocks by binding them to nodes and allowing
100	  memory policies to be used for prioritizing and controlling
101	  allocation behaviour.
102
103config NODES_SHIFT
104	int
105	default "3" if CPU_SUBTYPE_SHX3
106	default "1"
107	depends on NEED_MULTIPLE_NODES
108
109config ARCH_FLATMEM_ENABLE
110	def_bool y
111	depends on !NUMA
112
113config ARCH_SPARSEMEM_ENABLE
114	def_bool y
115	select SPARSEMEM_STATIC
116
117config ARCH_SPARSEMEM_DEFAULT
118	def_bool y
119
120config MAX_ACTIVE_REGIONS
121	int
122	default "6" if (CPU_SUBTYPE_SHX3 && SPARSEMEM)
123	default "2" if SPARSEMEM && (CPU_SUBTYPE_SH7722 || \
124		       CPU_SUBTYPE_SH7785)
125	default "1"
126
127config ARCH_POPULATES_NODE_MAP
128	def_bool y
129
130config ARCH_SELECT_MEMORY_MODEL
131	def_bool y
132
133config ARCH_ENABLE_MEMORY_HOTPLUG
134	def_bool y
135	depends on SPARSEMEM
136
137config ARCH_MEMORY_PROBE
138	def_bool y
139	depends on MEMORY_HOTPLUG
140
141choice
142	prompt "Kernel page size"
143	default PAGE_SIZE_8KB if X2TLB
144	default PAGE_SIZE_4KB
145
146config PAGE_SIZE_4KB
147	bool "4kB"
148	depends on !MMU || !X2TLB
149	help
150	  This is the default page size used by all SuperH CPUs.
151
152config PAGE_SIZE_8KB
153	bool "8kB"
154	depends on !MMU || X2TLB
155	help
156	  This enables 8kB pages as supported by SH-X2 and later MMUs.
157
158config PAGE_SIZE_16KB
159	bool "16kB"
160	depends on !MMU
161	help
162	  This enables 16kB pages on MMU-less SH systems.
163
164config PAGE_SIZE_64KB
165	bool "64kB"
166	depends on !MMU || CPU_SH4 || CPU_SH5
167	help
168	  This enables support for 64kB pages, possible on all SH-4
169	  CPUs and later.
170
171endchoice
172
173config ENTRY_OFFSET
174	hex
175	default "0x00001000" if PAGE_SIZE_4KB
176	default "0x00002000" if PAGE_SIZE_8KB
177	default "0x00004000" if PAGE_SIZE_16KB
178	default "0x00010000" if PAGE_SIZE_64KB
179	default "0x00000000"
180
181choice
182	prompt "HugeTLB page size"
183	depends on HUGETLB_PAGE && (CPU_SH4 || CPU_SH5) && MMU
184	default HUGETLB_PAGE_SIZE_64K
185
186config HUGETLB_PAGE_SIZE_64K
187	bool "64kB"
188
189config HUGETLB_PAGE_SIZE_256K
190	bool "256kB"
191	depends on X2TLB
192
193config HUGETLB_PAGE_SIZE_1MB
194	bool "1MB"
195
196config HUGETLB_PAGE_SIZE_4MB
197	bool "4MB"
198	depends on X2TLB
199
200config HUGETLB_PAGE_SIZE_64MB
201	bool "64MB"
202	depends on X2TLB
203
204config HUGETLB_PAGE_SIZE_512MB
205	bool "512MB"
206	depends on CPU_SH5
207
208endchoice
209
210source "mm/Kconfig"
211
212endmenu
213
214menu "Cache configuration"
215
216config SH7705_CACHE_32KB
217	bool "Enable 32KB cache size for SH7705"
218	depends on CPU_SUBTYPE_SH7705
219	default y
220
221config SH_DIRECT_MAPPED
222	bool "Use direct-mapped caching"
223	default n
224	help
225	  Selecting this option will configure the caches to be direct-mapped,
226	  even if the cache supports a 2 or 4-way mode. This is useful primarily
227	  for debugging on platforms with 2 and 4-way caches (SH7750R/SH7751R,
228	  SH4-202, SH4-501, etc.)
229
230	  Turn this option off for platforms that do not have a direct-mapped
231	  cache, and you have no need to run the caches in such a configuration.
232
233choice
234	prompt "Cache mode"
235	default CACHE_WRITEBACK if CPU_SH2A || CPU_SH3 || CPU_SH4 || CPU_SH5
236	default CACHE_WRITETHROUGH if (CPU_SH2 && !CPU_SH2A)
237
238config CACHE_WRITEBACK
239	bool "Write-back"
240	depends on CPU_SH2A || CPU_SH3 || CPU_SH4 || CPU_SH5
241
242config CACHE_WRITETHROUGH
243	bool "Write-through"
244	help
245	  Selecting this option will configure the caches in write-through
246	  mode, as opposed to the default write-back configuration.
247
248	  Since there's sill some aliasing issues on SH-4, this option will
249	  unfortunately still require the majority of flushing functions to
250	  be implemented to deal with aliasing.
251
252	  If unsure, say N.
253
254config CACHE_OFF
255	bool "Off"
256
257endchoice
258
259endmenu
260