xref: /openbmc/linux/drivers/mtd/chips/Kconfig (revision f15cbe6f)
1# drivers/mtd/chips/Kconfig
2
3menu "RAM/ROM/Flash chip drivers"
4	depends on MTD!=n
5
6config MTD_CFI
7	tristate "Detect flash chips by Common Flash Interface (CFI) probe"
8	select MTD_GEN_PROBE
9	help
10	  The Common Flash Interface specification was developed by Intel,
11	  AMD and other flash manufactures that provides a universal method
12	  for probing the capabilities of flash devices. If you wish to
13	  support any device that is CFI-compliant, you need to enable this
14	  option. Visit <http://www.amd.com/products/nvd/overview/cfi.html>
15	  for more information on CFI.
16
17config MTD_JEDECPROBE
18	tristate "Detect non-CFI AMD/JEDEC-compatible flash chips"
19	select MTD_GEN_PROBE
20	help
21	  This option enables JEDEC-style probing of flash chips which are not
22	  compatible with the Common Flash Interface, but will use the common
23	  CFI-targetted flash drivers for any chips which are identified which
24	  are in fact compatible in all but the probe method. This actually
25	  covers most AMD/Fujitsu-compatible chips and also non-CFI
26	  Intel chips.
27
28config MTD_GEN_PROBE
29	tristate
30
31config MTD_CFI_ADV_OPTIONS
32	bool "Flash chip driver advanced configuration options"
33	depends on MTD_GEN_PROBE
34	help
35	  If you need to specify a specific endianness for access to flash
36	  chips, or if you wish to reduce the size of the kernel by including
37	  support for only specific arrangements of flash chips, say 'Y'. This
38	  option does not directly affect the code, but will enable other
39	  configuration options which allow you to do so.
40
41	  If unsure, say 'N'.
42
43choice
44	prompt "Flash cmd/query data swapping"
45	depends on MTD_CFI_ADV_OPTIONS
46	default MTD_CFI_NOSWAP
47
48config MTD_CFI_NOSWAP
49	bool "NO"
50	---help---
51	  This option defines the way in which the CPU attempts to arrange
52	  data bits when writing the 'magic' commands to the chips. Saying
53	  'NO', which is the default when CONFIG_MTD_CFI_ADV_OPTIONS isn't
54	  enabled, means that the CPU will not do any swapping; the chips
55	  are expected to be wired to the CPU in 'host-endian' form.
56	  Specific arrangements are possible with the BIG_ENDIAN_BYTE and
57	  LITTLE_ENDIAN_BYTE, if the bytes are reversed.
58
59	  If you have a LART, on which the data (and address) lines were
60	  connected in a fashion which ensured that the nets were as short
61	  as possible, resulting in a bit-shuffling which seems utterly
62	  random to the untrained eye, you need the LART_ENDIAN_BYTE option.
63
64	  Yes, there really exists something sicker than PDP-endian :)
65
66config MTD_CFI_BE_BYTE_SWAP
67	bool "BIG_ENDIAN_BYTE"
68
69config MTD_CFI_LE_BYTE_SWAP
70	bool "LITTLE_ENDIAN_BYTE"
71
72endchoice
73
74config MTD_CFI_GEOMETRY
75	bool "Specific CFI Flash geometry selection"
76	depends on MTD_CFI_ADV_OPTIONS
77	help
78	  This option does not affect the code directly, but will enable
79	  some other configuration options which would allow you to reduce
80	  the size of the kernel by including support for only certain
81	  arrangements of CFI chips. If unsure, say 'N' and all options
82	  which are supported by the current code will be enabled.
83
84config MTD_MAP_BANK_WIDTH_1
85	bool "Support  8-bit buswidth" if MTD_CFI_GEOMETRY
86	default y
87	help
88	  If you wish to support CFI devices on a physical bus which is
89	  8 bits wide, say 'Y'.
90
91config MTD_MAP_BANK_WIDTH_2
92	bool "Support 16-bit buswidth" if MTD_CFI_GEOMETRY
93	default y
94	help
95	  If you wish to support CFI devices on a physical bus which is
96	  16 bits wide, say 'Y'.
97
98config MTD_MAP_BANK_WIDTH_4
99	bool "Support 32-bit buswidth" if MTD_CFI_GEOMETRY
100	default y
101	help
102	  If you wish to support CFI devices on a physical bus which is
103	  32 bits wide, say 'Y'.
104
105config MTD_MAP_BANK_WIDTH_8
106	bool "Support 64-bit buswidth" if MTD_CFI_GEOMETRY
107	default n
108	help
109	  If you wish to support CFI devices on a physical bus which is
110	  64 bits wide, say 'Y'.
111
112config MTD_MAP_BANK_WIDTH_16
113	bool "Support 128-bit buswidth" if MTD_CFI_GEOMETRY
114	default n
115	help
116	  If you wish to support CFI devices on a physical bus which is
117	  128 bits wide, say 'Y'.
118
119config MTD_MAP_BANK_WIDTH_32
120	bool "Support 256-bit buswidth" if MTD_CFI_GEOMETRY
121	default n
122	help
123	  If you wish to support CFI devices on a physical bus which is
124	  256 bits wide, say 'Y'.
125
126config MTD_CFI_I1
127	bool "Support 1-chip flash interleave" if MTD_CFI_GEOMETRY
128	default y
129	help
130	  If your flash chips are not interleaved - i.e. you only have one
131	  flash chip addressed by each bus cycle, then say 'Y'.
132
133config MTD_CFI_I2
134	bool "Support 2-chip flash interleave" if MTD_CFI_GEOMETRY
135	default y
136	help
137	  If your flash chips are interleaved in pairs - i.e. you have two
138	  flash chips addressed by each bus cycle, then say 'Y'.
139
140config MTD_CFI_I4
141	bool "Support 4-chip flash interleave" if MTD_CFI_GEOMETRY
142	default n
143	help
144	  If your flash chips are interleaved in fours - i.e. you have four
145	  flash chips addressed by each bus cycle, then say 'Y'.
146
147config MTD_CFI_I8
148	bool "Support 8-chip flash interleave" if MTD_CFI_GEOMETRY
149	default n
150	help
151	  If your flash chips are interleaved in eights - i.e. you have eight
152	  flash chips addressed by each bus cycle, then say 'Y'.
153
154config MTD_OTP
155	bool "Protection Registers aka one-time programmable (OTP) bits"
156	depends on MTD_CFI_ADV_OPTIONS
157	default n
158	help
159	  This enables support for reading, writing and locking so called
160	  "Protection Registers" present on some flash chips.
161	  A subset of them are pre-programmed at the factory with a
162	  unique set of values. The rest is user-programmable.
163
164	  The user-programmable Protection Registers contain one-time
165	  programmable (OTP) bits; when programmed, register bits cannot be
166	  erased. Each Protection Register can be accessed multiple times to
167	  program individual bits, as long as the register remains unlocked.
168
169	  Each Protection Register has an associated Lock Register bit. When a
170	  Lock Register bit is programmed, the associated Protection Register
171	  can only be read; it can no longer be programmed. Additionally,
172	  because the Lock Register bits themselves are OTP, when programmed,
173	  Lock Register bits cannot be erased. Therefore, when a Protection
174	  Register is locked, it cannot be unlocked.
175
176	  This feature should therefore be used with extreme care. Any mistake
177	  in the programming of OTP bits will waste them.
178
179config MTD_CFI_INTELEXT
180	tristate "Support for Intel/Sharp flash chips"
181	depends on MTD_GEN_PROBE
182	select MTD_CFI_UTIL
183	help
184	  The Common Flash Interface defines a number of different command
185	  sets which a CFI-compliant chip may claim to implement. This code
186	  provides support for one of those command sets, used on Intel
187	  StrataFlash and other parts.
188
189config MTD_CFI_AMDSTD
190	tristate "Support for AMD/Fujitsu flash chips"
191	depends on MTD_GEN_PROBE
192	select MTD_CFI_UTIL
193	help
194	  The Common Flash Interface defines a number of different command
195	  sets which a CFI-compliant chip may claim to implement. This code
196	  provides support for one of those command sets, used on chips
197	  including the AMD Am29LV320.
198
199config MTD_CFI_STAA
200	tristate "Support for ST (Advanced Architecture) flash chips"
201	depends on MTD_GEN_PROBE
202	select MTD_CFI_UTIL
203	help
204	  The Common Flash Interface defines a number of different command
205	  sets which a CFI-compliant chip may claim to implement. This code
206	  provides support for one of those command sets.
207
208config MTD_CFI_UTIL
209	tristate
210
211config MTD_RAM
212	tristate "Support for RAM chips in bus mapping"
213	help
214	  This option enables basic support for RAM chips accessed through
215	  a bus mapping driver.
216
217config MTD_ROM
218	tristate "Support for ROM chips in bus mapping"
219	help
220	  This option enables basic support for ROM chips accessed through
221	  a bus mapping driver.
222
223config MTD_ABSENT
224	tristate "Support for absent chips in bus mapping"
225	help
226	  This option enables support for a dummy probing driver used to
227	  allocated placeholder MTD devices on systems that have socketed
228	  or removable media.  Use of this driver as a fallback chip probe
229	  preserves the expected registration order of MTD device nodes on
230	  the system regardless of media presence.  Device nodes created
231	  with this driver will return -ENODEV upon access.
232
233config MTD_XIP
234	bool "XIP aware MTD support"
235	depends on !SMP && (MTD_CFI_INTELEXT || MTD_CFI_AMDSTD) && EXPERIMENTAL && ARCH_MTD_XIP
236	default y if XIP_KERNEL
237	help
238	  This allows MTD support to work with flash memory which is also
239	  used for XIP purposes.  If you're not sure what this is all about
240	  then say N.
241
242endmenu
243
244