menu "Library routines" config ADDR_MAP bool "Enable support for non-identity virtual-physical mappings" help Enables helper code for implementing non-identity virtual-physical memory mappings for 32bit CPUs. This library only works in the post-relocation phase. config SYS_NUM_ADDR_MAP int "Size of the address-map table" depends on ADDR_MAP default 16 help Sets the number of entries in the virtual-physical mapping table. config BCH bool "Enable Software based BCH ECC" help Enables software based BCH ECC algorithm present in lib/bch.c This is used by SoC platforms which do not have built-in ELM hardware engine required for BCH ECC correction. config BINMAN_FDT bool "Allow access to binman information in the device tree" depends on BINMAN && DM && OF_CONTROL default y help This enables U-Boot to access information about binman entries, stored in the device tree in a binman node. Typical uses are to locate entries in the firmware image. See binman.h for the available functionality. config CC_OPTIMIZE_LIBS_FOR_SPEED bool "Optimize libraries for speed" help Enabling this option will pass "-O2" to gcc when compiling under "lib" directory. If unsure, say N. config DYNAMIC_CRC_TABLE bool "Enable Dynamic tables for CRC" help Enable this option to calculate entries for CRC tables at runtime. This can be helpful when reducing the size of the build image config HAVE_ARCH_IOMAP bool help Enable this option if architecture provides io{read,write}{8,16,32} I/O accessor functions. config HAVE_PRIVATE_LIBGCC bool config LIB_UUID bool config PRINTF bool default y config SPL_PRINTF bool select SPL_SPRINTF select SPL_STRTO if !SPL_USE_TINY_PRINTF config TPL_PRINTF bool select TPL_SPRINTF select TPL_STRTO if !TPL_USE_TINY_PRINTF config SPRINTF bool default y config SPL_SPRINTF bool config TPL_SPRINTF bool config SSCANF bool default n config STRTO bool default y config SPL_STRTO bool config TPL_STRTO bool config IMAGE_SPARSE bool config IMAGE_SPARSE_FILLBUF_SIZE hex "Android sparse image CHUNK_TYPE_FILL buffer size" default 0x80000 depends on IMAGE_SPARSE help Set the size of the fill buffer used when processing CHUNK_TYPE_FILL chunks. config USE_PRIVATE_LIBGCC bool "Use private libgcc" depends on HAVE_PRIVATE_LIBGCC default y if HAVE_PRIVATE_LIBGCC && ((ARM && !ARM64) || MIPS) help This option allows you to use the built-in libgcc implementation of U-Boot instead of the one provided by the compiler. If unsure, say N. config SYS_HZ int default 1000 help The frequency of the timer returned by get_timer(). get_timer() must operate in milliseconds and this option must be set to 1000. config SPL_USE_TINY_PRINTF bool "Enable tiny printf() version in SPL" depends on SPL default y help This option enables a tiny, stripped down printf version. This should only be used in space limited environments, like SPL versions with hard memory limits. This version reduces the code size by about 2.5KiB on armv7. The supported format specifiers are %c, %s, %u/%d and %x. config TPL_USE_TINY_PRINTF bool "Enable tiny printf() version in TPL" depends on TPL default y if SPL_USE_TINY_PRINTF help This option enables a tiny, stripped down printf version. This should only be used in space limited environments, like SPL versions with hard memory limits. This version reduces the code size by about 2.5KiB on armv7. The supported format specifiers are %c, %s, %u/%d and %x. config PANIC_HANG bool "Do not reset the system on fatal error" help Define this option to stop the system in case of a fatal error, so that you have to reset it manually. This is probably NOT a good idea for an embedded system where you want the system to reboot automatically as fast as possible, but it may be useful during development since you can try to debug the conditions that lead to the situation. config REGEX bool "Enable regular expression support" default y if NET help If this variable is defined, U-Boot is linked against the SLRE (Super Light Regular Expression) library, which adds regex support to some commands, for example "env grep" and "setexpr". choice prompt "Pseudo-random library support type" depends on NET_RANDOM_ETHADDR || RANDOM_UUID || CMD_UUID || \ RNG_SANDBOX || UT_LIB && AES || FAT_WRITE default LIB_RAND help Select the library to provide pseudo-random number generator functions. LIB_HW_RAND supports certain hardware engines that provide this functionality. If in doubt, select LIB_RAND. config LIB_RAND bool "Pseudo-random library support" config LIB_HW_RAND bool "HW Engine for random library support" endchoice config SPL_TINY_MEMSET bool "Use a very small memset() in SPL" help The faster memset() is the arch-specific one (if available) enabled by CONFIG_USE_ARCH_MEMSET. If that is not enabled, we can still get better performance by writing a word at a time. But in very size-constrained environments even this may be too big. Enable this option to reduce code size slightly at the cost of some speed. config TPL_TINY_MEMSET bool "Use a very small memset() in TPL" help The faster memset() is the arch-specific one (if available) enabled by CONFIG_USE_ARCH_MEMSET. If that is not enabled, we can still get better performance by writing a word at a time. But in very size-constrained environments even this may be too big. Enable this option to reduce code size slightly at the cost of some speed. config RBTREE bool config BITREVERSE bool "Bit reverse library from Linux" config TRACE bool "Support for tracing of function calls and timing" imply CMD_TRACE select TIMER_EARLY help Enables function tracing within U-Boot. This allows recording of call traces including timing information. The command can write data to memory for exporting for analysis (e.g. using bootchart). See doc/README.trace for full details. config TRACE_BUFFER_SIZE hex "Size of trace buffer in U-Boot" depends on TRACE default 0x01000000 help Sets the size of the trace buffer in U-Boot. This is allocated from memory during relocation. If this buffer is too small, the trace history will be truncated, with later records omitted. If early trace is enabled (i.e. before relocation), this buffer must be large enough to include all the data from the early trace buffer as well, since this is copied over to the main buffer during relocation. A trace record is emitted for each function call and each record is 12 bytes (see struct trace_call). A suggested minimum size is 1MB. If the size is too small then 'trace stats' will show a message saying how many records were dropped due to buffer overflow. config TRACE_CALL_DEPTH_LIMIT int "Trace call depth limit" depends on TRACE default 15 help Sets the maximum call depth up to which function calls are recorded. config TRACE_EARLY bool "Enable tracing before relocation" depends on TRACE help Sometimes it is helpful to trace execution of U-Boot before relocation. This is possible by using a arch-specific, fixed buffer position in memory. Enable this option to start tracing as early as possible after U-Boot starts. config TRACE_EARLY_SIZE hex "Size of early trace buffer in U-Boot" depends on TRACE_EARLY default 0x00100000 help Sets the size of the early trace buffer in bytes. This is used to hold tracing information before relocation. config TRACE_EARLY_CALL_DEPTH_LIMIT int "Early trace call depth limit" depends on TRACE_EARLY default 200 help Sets the maximum call depth up to which function calls are recorded during early tracing. config TRACE_EARLY_ADDR hex "Address of early trace buffer in U-Boot" depends on TRACE_EARLY default 0x00100000 help Sets the address of the early trace buffer in U-Boot. This memory must be accessible before relocation. A trace record is emitted for each function call and each record is 12 bytes (see struct trace_call). A suggested minimum size is 1MB. If the size is too small then the message which says the amount of early data being coped will the the same as the source lib/dhry/Kconfig menu "Security support" config AES bool "Support the AES algorithm" help This provides a means to encrypt and decrypt data using the AES (Advanced Encryption Standard). This algorithm uses a symetric key and is widely used as a streaming cipher. Different key lengths are supported by the algorithm but only a 128-bit key is supported at present. source lib/rsa/Kconfig source lib/crypto/Kconfig config TPM bool "Trusted Platform Module (TPM) Support" depends on DM help This enables support for TPMs which can be used to provide security features for your board. The TPM can be connected via LPC or I2C and a sandbox TPM is provided for testing purposes. Use the 'tpm' command to interactive the TPM. Driver model support is provided for the low-level TPM interface, but only one TPM is supported at a time by the TPM library. config SPL_TPM bool "Trusted Platform Module (TPM) Support in SPL" depends on SPL_DM help This enables support for TPMs which can be used to provide security features for your board. The TPM can be connected via LPC or I2C and a sandbox TPM is provided for testing purposes. Use the 'tpm' command to interactive the TPM. Driver model support is provided for the low-level TPM interface, but only one TPM is supported at a time by the TPM library. config TPL_TPM bool "Trusted Platform Module (TPM) Support in TPL" depends on TPL_DM help This enables support for TPMs which can be used to provide security features for your board. The TPM can be connected via LPC or I2C and a sandbox TPM is provided for testing purposes. Use the 'tpm' command to interactive the TPM. Driver model support is provided for the low-level TPM interface, but only one TPM is supported at a time by the TPM library. endmenu menu "Android Verified Boot" config LIBAVB bool "Android Verified Boot 2.0 support" depends on ANDROID_BOOT_IMAGE default n help This enables support of Android Verified Boot 2.0 which can be used to assure the end user of the integrity of the software running on a device. Introduces such features as boot chain of trust, rollback protection etc. endmenu menu "Hashing Support" config SHA1 bool "Enable SHA1 support" help This option enables support of hashing using SHA1 algorithm. The hash is calculated in software. The SHA1 algorithm produces a 160-bit (20-byte) hash value (digest). config SHA256 bool "Enable SHA256 support" help This option enables support of hashing using SHA256 algorithm. The hash is calculated in software. The SHA256 algorithm produces a 256-bit (32-byte) hash value (digest). config SHA512_ALGO bool "Enable SHA512 algorithm" help This option enables support of internal SHA512 algorithm. config SHA512 bool "Enable SHA512 support" depends on SHA512_ALGO help This option enables support of hashing using SHA512 algorithm. The hash is calculated in software. The SHA512 algorithm produces a 512-bit (64-byte) hash value (digest). config SHA384 bool "Enable SHA384 support" depends on SHA512_ALGO help This option enables support of hashing using SHA384 algorithm. The hash is calculated in software. The SHA384 algorithm produces a 384-bit (48-byte) hash value (digest). config SHA_HW_ACCEL bool "Enable hashing using hardware" help This option enables hardware acceleration for SHA hashing. This affects the 'hash' command and also the hash_lookup_algo() function. config SHA_PROG_HW_ACCEL bool "Enable Progressive hashing support using hardware" depends on SHA_HW_ACCEL help This option enables hardware-acceleration for SHA progressive hashing. Data can be streamed in a block at a time and the hashing is performed in hardware. config MD5 bool "Support MD5 algorithm" help This option enables MD5 support. MD5 is an algorithm designed in 1991 that produces a 16-byte digest (or checksum) from its input data. It has a number of vulnerabilities which preclude its use in security applications, but it can be useful for providing a quick checksum of a block of data. config SPL_MD5 bool "Support MD5 algorithm in SPL" help This option enables MD5 support in SPL. MD5 is an algorithm designed in 1991 that produces a 16-byte digest (or checksum) from its input data. It has a number of vulnerabilities which preclude its use in security applications, but it can be useful for providing a quick checksum of a block of data. config CRC32C bool config XXHASH bool endmenu menu "Compression Support" config LZ4 bool "Enable LZ4 decompression support" help If this option is set, support for LZ4 compressed images is included. The LZ4 algorithm can run in-place as long as the compressed image is loaded to the end of the output buffer, and trades lower compression ratios for much faster decompression. NOTE: This implements the release version of the LZ4 frame format as generated by default by the 'lz4' command line tool. This is not the same as the outdated, less efficient legacy frame format currently (2015) implemented in the Linux kernel (generated by 'lz4 -l'). The two formats are incompatible. config LZMA bool "Enable LZMA decompression support" help This enables support for LZMA (Lempel-Ziv-Markov chain algorithm), a dictionary compression algorithm that provides a high compression ratio and fairly fast decompression speed. See also CONFIG_CMD_LZMADEC which provides a decode command. config LZO bool "Enable LZO decompression support" help This enables support for LZO compression algorithm.r config GZIP bool "Enable gzip decompression support" select ZLIB default y help This enables support for GZIP compression algorithm. config ZLIB_UNCOMPRESS bool "Enables zlib's uncompress() functionality" help This enables an extra zlib functionality: the uncompress() function, which decompresses data from a buffer into another, knowing their sizes. Unlike gunzip(), there is no header parsing. config GZIP_COMPRESSED bool select ZLIB config BZIP2 bool "Enable bzip2 decompression support" help This enables support for BZIP2 compression algorithm. config ZLIB bool default y help This enables ZLIB compression lib. config ZSTD bool "Enable Zstandard decompression support" select XXHASH help This enables Zstandard decompression library. config SPL_LZ4 bool "Enable LZ4 decompression support in SPL" help This enables support for the LZ4 decompression algorithm in SPL. LZ4 is a lossless data compression algorithm that is focused on fast compression and decompression speed. It belongs to the LZ77 family of byte-oriented compression schemes. config SPL_LZMA bool "Enable LZMA decompression support for SPL build" help This enables support for LZMA compression algorithm for SPL boot. config SPL_LZO bool "Enable LZO decompression support in SPL" help This enables support for LZO compression algorithm in the SPL. config SPL_GZIP bool "Enable gzip decompression support for SPL build" select SPL_ZLIB help This enables support for GZIP compression altorithm for SPL boot. config SPL_ZLIB bool help This enables compression lib for SPL boot. config SPL_ZSTD bool "Enable Zstandard decompression support in SPL" select XXHASH help This enables Zstandard decompression library in the SPL. endmenu config ERRNO_STR bool "Enable function for getting errno-related string message" help The function errno_str(int errno), returns a pointer to the errno corresponding text message: - if errno is null or positive number - a pointer to "Success" message - if errno is negative - a pointer to errno related message config HEXDUMP bool "Enable hexdump" help This enables functions for printing dumps of binary data. config SPL_HEXDUMP bool "Enable hexdump in SPL" depends on HEXDUMP default y help This enables functions for printing dumps of binary data in SPL. config GETOPT bool "Enable getopt" help This enables functions for parsing command-line options. config OF_LIBFDT bool "Enable the FDT library" default y if OF_CONTROL help This enables the FDT library (libfdt). It provides functions for accessing binary device tree images in memory, such as adding and removing nodes and properties, scanning through the tree and finding particular compatible nodes. The library operates on a flattened version of the device tree. config OF_LIBFDT_ASSUME_MASK hex "Mask of conditions to assume for libfdt" depends on OF_LIBFDT || FIT default 0 help Use this to change the assumptions made by libfdt about the device tree it is working with. A value of 0 means that no assumptions are made, and libfdt is able to deal with malicious data. A value of 0xff means all assumptions are made and any invalid data may cause unsafe execution. See FDT_ASSUME_PERFECT, etc. in libfdt_internal.h config OF_LIBFDT_OVERLAY bool "Enable the FDT library overlay support" depends on OF_LIBFDT default y if ARCH_OMAP2PLUS || ARCH_KEYSTONE help This enables the FDT library (libfdt) overlay support. config SPL_OF_LIBFDT bool "Enable the FDT library for SPL" default y if SPL_OF_CONTROL help This enables the FDT library (libfdt). It provides functions for accessing binary device tree images in memory, such as adding and removing nodes and properties, scanning through the tree and finding particular compatible nodes. The library operates on a flattened version of the device tree. config SPL_OF_LIBFDT_ASSUME_MASK hex "Mask of conditions to assume for libfdt" depends on SPL_OF_LIBFDT || FIT default 0xff help Use this to change the assumptions made by libfdt in SPL about the device tree it is working with. A value of 0 means that no assumptions are made, and libfdt is able to deal with malicious data. A value of 0xff means all assumptions are made and any invalid data may cause unsafe execution. See FDT_ASSUME_PERFECT, etc. in libfdt_internal.h config TPL_OF_LIBFDT bool "Enable the FDT library for TPL" default y if TPL_OF_CONTROL help This enables the FDT library (libfdt). It provides functions for accessing binary device tree images in memory, such as adding and removing nodes and properties, scanning through the tree and finding particular compatible nodes. The library operates on a flattened version of the device tree. config TPL_OF_LIBFDT_ASSUME_MASK hex "Mask of conditions to assume for libfdt" depends on TPL_OF_LIBFDT || FIT default 0xff help Use this to change the assumptions made by libfdt in TPL about the device tree it is working with. A value of 0 means that no assumptions are made, and libfdt is able to deal with malicious data. A value of 0xff means all assumptions are made and any invalid data may cause unsafe execution. See FDT_ASSUME_PERFECT, etc. in libfdt_internal.h config FDT_FIXUP_PARTITIONS bool "overwrite MTD partitions in DTS through defined in 'mtdparts'" depends on OF_LIBFDT depends on CMD_MTDPARTS help Allow overwriting defined partitions in the device tree blob using partition info defined in the 'mtdparts' environment variable. menu "System tables" depends on (!EFI && !SYS_COREBOOT) || (ARM && EFI_LOADER) config BLOBLIST_TABLES bool "Put tables in a bloblist" depends on X86 && BLOBLIST help Normally tables are placed at address 0xf0000 and can be up to 64KB long. With this option, tables are instead placed in the bloblist with a pointer from 0xf0000. The size can then be larger and the tables can be placed high in memory. config GENERATE_SMBIOS_TABLE bool "Generate an SMBIOS (System Management BIOS) table" default y depends on X86 || EFI_LOADER help The System Management BIOS (SMBIOS) specification addresses how motherboard and system vendors present management information about their products in a standard format by extending the BIOS interface on Intel architecture systems. Check http://www.dmtf.org/standards/smbios for details. See also SMBIOS_SYSINFO which allows SMBIOS values to be provided in the devicetree. endmenu config ASN1_COMPILER bool config ASN1_DECODER bool help Enable asn1 decoder library. config OID_REGISTRY bool help Enable fast lookup object identifier registry. config SMBIOS_PARSER bool "SMBIOS parser" help A simple parser for SMBIOS data. source lib/efi/Kconfig source lib/efi_loader/Kconfig source lib/optee/Kconfig config TEST_FDTDEC bool "enable fdtdec test" depends on OF_LIBFDT config LIB_DATE bool config LIB_ELF bool help Support basic elf loading/validating functions. This supports for 32 bit and 64 bit versions. config LMB bool "Enable the logical memory blocks library (lmb)" default y if ARC || ARM || M68K || MICROBLAZE || MIPS || NDS32 || \ NIOS2 || PPC || RISCV || SANDBOX || SH || X86 || XTENSA help Support the library logical memory blocks. config LMB_MAX_REGIONS int "Number of memory and reserved regions in lmb lib" depends on LMB default 8 help Define the number of supported regions, memory and reserved, in the library logical memory blocks. endmenu config PHANDLE_CHECK_SEQ bool "Enable phandle check while getting sequence number" default n help When there are multiple device tree nodes with same name, enable this config option to distinguish them using phandles in fdtdec_get_alias_seq() function.