Kconfig (8484B)
1# SPDX-License-Identifier: GPL-2.0-only 2menu "RAM/ROM/Flash chip drivers" 3 depends on MTD!=n 4 5config MTD_CFI 6 tristate "Detect flash chips by Common Flash Interface (CFI) probe" 7 select MTD_GEN_PROBE 8 select MTD_CFI_UTIL 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 <https://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 select MTD_CFI_UTIL 21 help 22 This option enables JEDEC-style probing of flash chips which are not 23 compatible with the Common Flash Interface, but will use the common 24 CFI-targeted flash drivers for any chips which are identified which 25 are in fact compatible in all but the probe method. This actually 26 covers most AMD/Fujitsu-compatible chips and also non-CFI 27 Intel chips. 28 29config MTD_GEN_PROBE 30 tristate 31 32config MTD_CFI_ADV_OPTIONS 33 bool "Flash chip driver advanced configuration options" 34 depends on MTD_GEN_PROBE 35 help 36 If you need to specify a specific endianness for access to flash 37 chips, or if you wish to reduce the size of the kernel by including 38 support for only specific arrangements of flash chips, say 'Y'. This 39 option does not directly affect the code, but will enable other 40 configuration options which allow you to do so. 41 42 If unsure, say 'N'. 43 44choice 45 prompt "Flash cmd/query data swapping" 46 depends on MTD_CFI_ADV_OPTIONS 47 default MTD_CFI_NOSWAP 48 help 49 This option defines the way in which the CPU attempts to arrange 50 data bits when writing the 'magic' commands to the chips. Saying 51 'NO', which is the default when CONFIG_MTD_CFI_ADV_OPTIONS isn't 52 enabled, means that the CPU will not do any swapping; the chips 53 are expected to be wired to the CPU in 'host-endian' form. 54 Specific arrangements are possible with the BIG_ENDIAN_BYTE and 55 LITTLE_ENDIAN_BYTE, if the bytes are reversed. 56 57config MTD_CFI_NOSWAP 58 depends on !ARCH_IXP4XX || CPU_BIG_ENDIAN 59 bool "NO" 60 61config MTD_CFI_BE_BYTE_SWAP 62 bool "BIG_ENDIAN_BYTE" 63 64config MTD_CFI_LE_BYTE_SWAP 65 depends on !ARCH_IXP4XX 66 bool "LITTLE_ENDIAN_BYTE" 67 68endchoice 69 70config MTD_CFI_GEOMETRY 71 bool "Specific CFI Flash geometry selection" 72 depends on MTD_CFI_ADV_OPTIONS 73 select MTD_MAP_BANK_WIDTH_1 if !(MTD_MAP_BANK_WIDTH_2 || \ 74 MTD_MAP_BANK_WIDTH_4 || MTD_MAP_BANK_WIDTH_8 || \ 75 MTD_MAP_BANK_WIDTH_16 || MTD_MAP_BANK_WIDTH_32) 76 select MTD_CFI_I1 if !(MTD_CFI_I2 || MTD_CFI_I4 || MTD_CFI_I8) 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 select MTD_COMPLEX_MAPPINGS if HAS_IOMEM 122 default n 123 help 124 If you wish to support CFI devices on a physical bus which is 125 256 bits wide, say 'Y'. 126 127config MTD_CFI_I1 128 bool "Support 1-chip flash interleave" if MTD_CFI_GEOMETRY 129 default y 130 help 131 If your flash chips are not interleaved - i.e. you only have one 132 flash chip addressed by each bus cycle, then say 'Y'. 133 134config MTD_CFI_I2 135 bool "Support 2-chip flash interleave" if MTD_CFI_GEOMETRY 136 default y 137 help 138 If your flash chips are interleaved in pairs - i.e. you have two 139 flash chips addressed by each bus cycle, then say 'Y'. 140 141config MTD_CFI_I4 142 bool "Support 4-chip flash interleave" if MTD_CFI_GEOMETRY 143 default n 144 help 145 If your flash chips are interleaved in fours - i.e. you have four 146 flash chips addressed by each bus cycle, then say 'Y'. 147 148config MTD_CFI_I8 149 bool "Support 8-chip flash interleave" if MTD_CFI_GEOMETRY 150 default n 151 help 152 If your flash chips are interleaved in eights - i.e. you have eight 153 flash chips addressed by each bus cycle, then say 'Y'. 154 155config MTD_OTP 156 bool "Protection Registers aka one-time programmable (OTP) bits" 157 depends on MTD_CFI_ADV_OPTIONS 158 default n 159 help 160 This enables support for reading, writing and locking so called 161 "Protection Registers" present on some flash chips. 162 A subset of them are pre-programmed at the factory with a 163 unique set of values. The rest is user-programmable. 164 165 The user-programmable Protection Registers contain one-time 166 programmable (OTP) bits; when programmed, register bits cannot be 167 erased. Each Protection Register can be accessed multiple times to 168 program individual bits, as long as the register remains unlocked. 169 170 Each Protection Register has an associated Lock Register bit. When a 171 Lock Register bit is programmed, the associated Protection Register 172 can only be read; it can no longer be programmed. Additionally, 173 because the Lock Register bits themselves are OTP, when programmed, 174 Lock Register bits cannot be erased. Therefore, when a Protection 175 Register is locked, it cannot be unlocked. 176 177 This feature should therefore be used with extreme care. Any mistake 178 in the programming of OTP bits will waste them. 179 180config MTD_CFI_INTELEXT 181 tristate "Support for CFI command set 0001 (Intel/Sharp chips)" 182 depends on MTD_GEN_PROBE 183 select MTD_CFI_UTIL 184 help 185 The Common Flash Interface defines a number of different command 186 sets which a CFI-compliant chip may claim to implement. This code 187 provides support for command set 0001, used on Intel StrataFlash 188 and other parts. 189 190config MTD_CFI_AMDSTD 191 tristate "Support for CFI command set 0002 (AMD/Fujitsu/Spansion chips)" 192 depends on MTD_GEN_PROBE 193 select MTD_CFI_UTIL 194 help 195 The Common Flash Interface defines a number of different command 196 sets which a CFI-compliant chip may claim to implement. This code 197 provides support for command set 0002, used on chips including 198 the AMD Am29LV320. 199 200config MTD_CFI_STAA 201 tristate "Support for CFI command set 0020 (ST (Advanced Architecture) chips)" 202 depends on MTD_GEN_PROBE 203 select MTD_CFI_UTIL 204 help 205 The Common Flash Interface defines a number of different command 206 sets which a CFI-compliant chip may claim to implement. This code 207 provides support for command set 0020. 208 209config MTD_CFI_UTIL 210 tristate 211 212config MTD_RAM 213 tristate "Support for RAM chips in bus mapping" 214 help 215 This option enables basic support for RAM chips accessed through 216 a bus mapping driver. 217 218config MTD_ROM 219 tristate "Support for ROM chips in bus mapping" 220 help 221 This option enables basic support for ROM chips accessed through 222 a bus mapping driver. 223 224config MTD_ABSENT 225 tristate "Support for absent chips in bus mapping" 226 help 227 This option enables support for a dummy probing driver used to 228 allocated placeholder MTD devices on systems that have socketed 229 or removable media. Use of this driver as a fallback chip probe 230 preserves the expected registration order of MTD device nodes on 231 the system regardless of media presence. Device nodes created 232 with this driver will return -ENODEV upon access. 233 234config MTD_XIP 235 bool "XIP aware MTD support" 236 depends on !SMP && (MTD_CFI_INTELEXT || MTD_CFI_AMDSTD) && ARCH_MTD_XIP 237 default y if XIP_KERNEL 238 help 239 This allows MTD support to work with flash memory which is also 240 used for XIP purposes. If you're not sure what this is all about 241 then say N. 242 243endmenu