xref: /openbmc/linux/arch/sh/mm/Kconfig (revision f5005f78) 
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 || !MMU
83
84config PMB
85	bool "Support 32-bit physical addressing through PMB"
86	depends on MMU && 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
114	select ARCH_WANT_NUMA_VARIABLE_LOCALITY
115	default n
116	help
117	  Some SH systems have many various memories scattered around
118	  the address space, each with varying latencies. This enables
119	  support for these blocks by binding them to nodes and allowing
120	  memory policies to be used for prioritizing and controlling
121	  allocation behaviour.
122
123config NODES_SHIFT
124	int
125	default "3" if CPU_SUBTYPE_SHX3
126	default "1"
127	depends on NEED_MULTIPLE_NODES
128
129config ARCH_FLATMEM_ENABLE
130	def_bool y
131	depends on !NUMA
132
133config ARCH_SPARSEMEM_ENABLE
134	def_bool y
135	select SPARSEMEM_STATIC
136
137config ARCH_SPARSEMEM_DEFAULT
138	def_bool y
139
140config ARCH_SELECT_MEMORY_MODEL
141	def_bool y
142
143config ARCH_ENABLE_MEMORY_HOTPLUG
144	def_bool y
145	depends on SPARSEMEM && MMU
146
147config ARCH_ENABLE_MEMORY_HOTREMOVE
148	def_bool y
149	depends on SPARSEMEM && MMU
150
151config ARCH_MEMORY_PROBE
152	def_bool y
153	depends on MEMORY_HOTPLUG
154
155config IOREMAP_FIXED
156       def_bool y
157       depends on X2TLB || SUPERH64
158
159config UNCACHED_MAPPING
160	bool
161
162config HAVE_SRAM_POOL
163	bool
164	select GENERIC_ALLOCATOR
165
166choice
167	prompt "Kernel page size"
168	default PAGE_SIZE_4KB
169
170config PAGE_SIZE_4KB
171	bool "4kB"
172	help
173	  This is the default page size used by all SuperH CPUs.
174
175config PAGE_SIZE_8KB
176	bool "8kB"
177	depends on !MMU || X2TLB
178	help
179	  This enables 8kB pages as supported by SH-X2 and later MMUs.
180
181config PAGE_SIZE_16KB
182	bool "16kB"
183	depends on !MMU
184	help
185	  This enables 16kB pages on MMU-less SH systems.
186
187config PAGE_SIZE_64KB
188	bool "64kB"
189	depends on !MMU || CPU_SH4 || CPU_SH5
190	help
191	  This enables support for 64kB pages, possible on all SH-4
192	  CPUs and later.
193
194endchoice
195
196choice
197	prompt "HugeTLB page size"
198	depends on HUGETLB_PAGE
199	default HUGETLB_PAGE_SIZE_1MB if PAGE_SIZE_64KB
200	default HUGETLB_PAGE_SIZE_64K
201
202config HUGETLB_PAGE_SIZE_64K
203	bool "64kB"
204	depends on !PAGE_SIZE_64KB
205
206config HUGETLB_PAGE_SIZE_256K
207	bool "256kB"
208	depends on X2TLB
209
210config HUGETLB_PAGE_SIZE_1MB
211	bool "1MB"
212
213config HUGETLB_PAGE_SIZE_4MB
214	bool "4MB"
215	depends on X2TLB
216
217config HUGETLB_PAGE_SIZE_64MB
218	bool "64MB"
219	depends on X2TLB
220
221config HUGETLB_PAGE_SIZE_512MB
222	bool "512MB"
223	depends on CPU_SH5
224
225endchoice
226
227source "mm/Kconfig"
228
229config SCHED_MC
230	bool "Multi-core scheduler support"
231	depends on SMP
232	default y
233	help
234	  Multi-core scheduler support improves the CPU scheduler's decision
235	  making when dealing with multi-core CPU chips at a cost of slightly
236	  increased overhead in some places. If unsure say N here.
237
238endmenu
239
240menu "Cache configuration"
241
242config SH7705_CACHE_32KB
243	bool "Enable 32KB cache size for SH7705"
244	depends on CPU_SUBTYPE_SH7705
245	default y
246
247choice
248	prompt "Cache mode"
249	default CACHE_WRITEBACK if CPU_SH2A || CPU_SH3 || CPU_SH4 || CPU_SH5
250	default CACHE_WRITETHROUGH if (CPU_SH2 && !CPU_SH2A)
251
252config CACHE_WRITEBACK
253	bool "Write-back"
254
255config CACHE_WRITETHROUGH
256	bool "Write-through"
257	help
258	  Selecting this option will configure the caches in write-through
259	  mode, as opposed to the default write-back configuration.
260
261	  Since there's sill some aliasing issues on SH-4, this option will
262	  unfortunately still require the majority of flushing functions to
263	  be implemented to deal with aliasing.
264
265	  If unsure, say N.
266
267config CACHE_OFF
268	bool "Off"
269
270endchoice
271
272endmenu
273