# SPDX-License-Identifier: GPL-2.0-only
menu "RAM/ROM/Flash chip drivers"
depends on MTD!=n
config MTD_CFI
tristate "Detect flash chips by Common Flash Interface (CFI) probe"
select MTD_GEN_PROBE
select MTD_CFI_UTIL
help
The Common Flash Interface specification was developed by Intel,
AMD and other flash manufactures that provides a universal method
for probing the capabilities of flash devices. If you wish to
support any device that is CFI-compliant, you need to enable this
option. Visit <https://www.amd.com/products/nvd/overview/cfi.html>
for more information on CFI.
config MTD_JEDECPROBE
tristate "Detect non-CFI AMD/JEDEC-compatible flash chips"
select MTD_GEN_PROBE
select MTD_CFI_UTIL
help
This option enables JEDEC-style probing of flash chips which are not
compatible with the Common Flash Interface, but will use the common
CFI-targeted flash drivers for any chips which are identified which
are in fact compatible in all but the probe method. This actually
covers most AMD/Fujitsu-compatible chips and also non-CFI
Intel chips.
config MTD_GEN_PROBE
tristate
config MTD_CFI_ADV_OPTIONS
bool "Flash chip driver advanced configuration options"
depends on MTD_GEN_PROBE
help
If you need to specify a specific endianness for access to flash
chips, or if you wish to reduce the size of the kernel by including
support for only specific arrangements of flash chips, say 'Y'. This
option does not directly affect the code, but will enable other
configuration options which allow you to do so.
If unsure, say 'N'.
choice
prompt "Flash cmd/query data swapping"
depends on MTD_CFI_ADV_OPTIONS
default MTD_CFI_NOSWAP
help
This option defines the way in which the CPU attempts to arrange
data bits when writing the 'magic' commands to the chips. Saying
'NO', which is the default when CONFIG_MTD_CFI_ADV_OPTIONS isn't
enabled, means that the CPU will not do any swapping; the chips
are expected to be wired to the CPU in 'host-endian' form.
Specific arrangements are possible with the BIG_ENDIAN_BYTE and
LITTLE_ENDIAN_BYTE, if the bytes are reversed.
config MTD_CFI_NOSWAP
depends on !ARCH_IXP4XX || CPU_BIG_ENDIAN
bool "NO"
config MTD_CFI_BE_BYTE_SWAP
bool "BIG_ENDIAN_BYTE"
config MTD_CFI_LE_BYTE_SWAP
depends on !ARCH_IXP4XX
bool "LITTLE_ENDIAN_BYTE"
endchoice
config MTD_CFI_GEOMETRY
bool "Specific CFI Flash geometry selection"
depends on MTD_CFI_ADV_OPTIONS
select MTD_MAP_BANK_WIDTH_1 if !(MTD_MAP_BANK_WIDTH_2 || \
MTD_MAP_BANK_WIDTH_4 || MTD_MAP_BANK_WIDTH_8 || \
MTD_MAP_BANK_WIDTH_16 || MTD_MAP_BANK_WIDTH_32)
select MTD_CFI_I1 if !(MTD_CFI_I2 || MTD_CFI_I4 || MTD_CFI_I8)
help
This option does not affect the code directly, but will enable
some other configuration options which would allow you to reduce
the size of the kernel by including support for only certain
arrangements of CFI chips. If unsure, say 'N' and all options
which are supported by the current code will be enabled.
config MTD_MAP_BANK_WIDTH_1
bool "Support 8-bit buswidth" if MTD_CFI_GEOMETRY
default y
help
If you wish to support CFI devices on a physical bus which is
8 bits wide, say 'Y'.
config MTD_MAP_BANK_WIDTH_2
bool "Support 16-bit buswidth" if MTD_CFI_GEOMETRY
default y
help
If you wish to support CFI devices on a physical bus which is
16 bits wide, say 'Y'.
config MTD_MAP_BANK_WIDTH_4
bool "Support 32-bit buswidth" if MTD_CFI_GEOMETRY
default y
help
If you wish to support CFI devices on a physical bus which is
32 bits wide, say 'Y'.
config MTD_MAP_BANK_WIDTH_8
bool "Support 64-bit buswidth" if MTD_CFI_GEOMETRY
default n
help
If you wish to support CFI devices on a physical bus which is
64 bits wide, say 'Y'.
config MTD_MAP_BANK_WIDTH_16
bool "Support 128-bit buswidth" if MTD_CFI_GEOMETRY
default n
help
If you wish to support CFI devices on a physical bus which is
128 bits wide, say 'Y'.
config MTD_MAP_BANK_WIDTH_32
bool "Support 256-bit buswidth" if MTD_CFI_GEOMETRY
select MTD_COMPLEX_MAPPINGS if HAS_IOMEM
default n
help
If you wish to support CFI devices on a physical bus which is
256 bits wide, say 'Y'.
config MTD_CFI_I1
bool "Support 1-chip flash interleave" if MTD_CFI_GEOMETRY
default y
help
If your flash chips are not interleaved - i.e. you only have one
flash chip addressed by each bus cycle, then say 'Y'.
config MTD_CFI_I2
bool "Support 2-chip flash interleave" if MTD_CFI_GEOMETRY
default y
help
If your flash chips are interleaved in pairs - i.e. you have two
flash chips addressed by each bus cycle, then say 'Y'.
config MTD_CFI_I4
bool "Support 4-chip flash interleave" if MTD_CFI_GEOMETRY
default n
help
If your flash chips are interleaved in fours - i.e. you have four
flash chips addressed by each bus cycle, then say 'Y'.
config MTD_CFI_I8
bool "Support 8-chip flash interleave" if MTD_CFI_GEOMETRY
default n
help
If your flash chips are interleaved in eights - i.e. you have eight
flash chips addressed by each bus cycle, then say 'Y'.
config MTD_OTP
bool "Protection Registers aka one-time programmable (OTP) bits"
depends on MTD_CFI_ADV_OPTIONS
default n
help
This enables support for reading, writing and locking so called
"Protection Registers" present on some flash chips.
A subset of them are pre-programmed at the factory with a
unique set of values. The rest is user-programmable.
The user-programmable Protection Registers contain one-time
programmable (OTP) bits; when programmed, register bits cannot be
erased. Each Protection Register can be accessed multiple times to
program individual bits, as long as the register remains unlocked.
Each Protection Register has an associated Lock Register bit. When a
Lock Register bit is programmed, the associated Protection Register
can only be read; it can no longer be programmed. Additionally,
because the Lock Register bits themselves are OTP, when programmed,
Lock Register bits cannot be erased. Therefore, when a Protection
Register is locked, it cannot be unlocked.
This feature should therefore be used with extreme care. Any mistake
in the programming of OTP bits will waste them.
config MTD_CFI_INTELEXT
tristate "Support for CFI command set 0001 (Intel/Sharp chips)"
depends on MTD_GEN_PROBE
select MTD_CFI_UTIL
help
The Common Flash Interface defines a number of different command
sets which a CFI-compliant chip may claim to implement. This code
provides support for command set 0001, used on Intel StrataFlash
and other parts.
config MTD_CFI_AMDSTD
tristate "Support for CFI command set 0002 (AMD/Fujitsu/Spansion chips)"
depends on MTD_GEN_PROBE
select MTD_CFI_UTIL
help
The Common Flash Interface defines a number of different command
sets which a CFI-compliant chip may claim to implement. This code
provides support for command set 0002, used on chips including
the AMD Am29LV320.
config MTD_CFI_STAA
tristate "Support for CFI command set 0020 (ST (Advanced Architecture) chips)"
depends on MTD_GEN_PROBE
select MTD_CFI_UTIL
help
The Common Flash Interface defines a number of different command
sets which a CFI-compliant chip may claim to implement. This code
provides support for command set 0020.
config MTD_CFI_UTIL
tristate
config MTD_RAM
tristate "Support for RAM chips in bus mapping"
help
This option enables basic support for RAM chips accessed through
a bus mapping driver.
config MTD_ROM
tristate "Support for ROM chips in bus mapping"
help
This option enables basic support for ROM chips accessed through
a bus mapping driver.
config MTD_ABSENT
tristate "Support for absent chips in bus mapping"
help
This option enables support for a dummy probing driver used to
allocated placeholder MTD devices on systems that have socketed
or removable media. Use of this driver as a fallback chip probe
preserves the expected registration order of MTD device nodes on
the system regardless of media presence. Device nodes created
with this driver will return -ENODEV upon access.
config MTD_XIP
bool "XIP aware MTD support"
depends on !SMP && (MTD_CFI_INTELEXT || MTD_CFI_AMDSTD) && ARCH_MTD_XIP
default y if XIP_KERNEL
help
This allows MTD support to work with flash memory which is also
used for XIP purposes. If you're not sure what this is all about
then say N.
endmenu
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