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		Set for common ddr init with serial presence detect in
		SPL binary.

		CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
		CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
		CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
		CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
		CONFIG_SYS_NAND_ECCBYTES
		Defines the size and behavior of the NAND that SPL uses
		to read U-Boot
		CONFIG_SPL_NAND_BOOT
		Add support NAND boot

		CONFIG_SYS_NAND_U_BOOT_OFFS
		Location in NAND to read U-Boot from

		CONFIG_SYS_NAND_U_BOOT_DST
		Location in memory to load U-Boot to

		CONFIG_SYS_NAND_U_BOOT_SIZE
		Size of image to load

		CONFIG_SYS_NAND_U_BOOT_START
		Entry point in loaded image to jump to

		CONFIG_SYS_NAND_HW_ECC_OOBFIRST
		Define this if you need to first read the OOB and then the
		data. This is used, for example, on davinci platforms.

		CONFIG_SPL_OMAP3_ID_NAND
		Support for an OMAP3-specific set of functions to return the
		ID and MFR of the first attached NAND chip, if present.

		CONFIG_SPL_RAM_DEVICE
		Support for running image already present in ram, in SPL binary
		CONFIG_SPL_PAD_TO
		Image offset to which the SPL should be padded before appending
		the SPL payload. By default, this is defined as
		CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
		CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
		payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
		CONFIG_SPL_TARGET
		Final target image containing SPL and payload.  Some SPLs
		use an arch-specific makefile fragment instead, for
		example if more than one image needs to be produced.

		CONFIG_FIT_SPL_PRINT
		Printing information about a FIT image adds quite a bit of
		code to SPL. So this is normally disabled in SPL. Use this
		option to re-enable it. This will affect the output of the
		bootm command when booting a FIT image.

- TPL framework
		CONFIG_TPL
		Enable building of TPL globally.

		CONFIG_TPL_PAD_TO
		Image offset to which the TPL should be padded before appending
		the TPL payload. By default, this is defined as
		CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
		CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
		payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
- Interrupt support (PPC):

		There are common interrupt_init() and timer_interrupt()
		for all PPC archs. interrupt_init() calls interrupt_init_cpu()
		for CPU specific initialization. interrupt_init_cpu()
		should set decrementer_count to appropriate value. If
		CPU resets decrementer automatically after interrupt
		(ppc4xx) it should set decrementer_count to zero.
		timer_interrupt() calls timer_interrupt_cpu() for CPU
		specific handling. If board has watchdog / status_led
		/ other_activity_monitor it works automatically from
		general timer_interrupt().
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Board initialization settings:
------------------------------

During Initialization u-boot calls a number of board specific functions
to allow the preparation of board specific prerequisites, e.g. pin setup
before drivers are initialized. To enable these callbacks the
following configuration macros have to be defined. Currently this is
architecture specific, so please check arch/your_architecture/lib/board.c
typically in board_init_f() and board_init_r().

- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
- CONFIG_BOARD_LATE_INIT: Call board_late_init()
- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
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Configuration Settings:
-----------------------

- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
		Optionally it can be defined to support 64-bit memory commands.

- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
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		undefine this when you're short of memory.

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- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
		width of the commands listed in the 'help' command output.

- CONFIG_SYS_PROMPT:	This is what U-Boot prints on the console to
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		prompt for user input.

- CONFIG_SYS_CBSIZE:	Buffer size for input from the Console
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- CONFIG_SYS_PBSIZE:	Buffer size for Console output
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- CONFIG_SYS_MAXARGS:	max. Number of arguments accepted for monitor commands
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- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
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		the application (usually a Linux kernel) when it is
		booted

- CONFIG_SYS_BAUDRATE_TABLE:
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		List of legal baudrate settings for this board.

- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
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		Begin and End addresses of the area used by the
		simple memory test.

- CONFIG_SYS_ALT_MEMTEST:
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		Enable an alternate, more extensive memory test.
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- CONFIG_SYS_MEMTEST_SCRATCH:
		Scratch address used by the alternate memory test
		You only need to set this if address zero isn't writeable

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- CONFIG_SYS_MEM_RESERVE_SECURE
		Only implemented for ARMv8 for now.
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		If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
		is substracted from total RAM and won't be reported to OS.
		This memory can be used as secure memory. A variable
		gd->arch.secure_ram is used to track the location. In systems
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		the RAM base is not zero, or RAM is divided into banks,
		this variable needs to be recalcuated to get the address.

- CONFIG_SYS_MEM_TOP_HIDE:
		If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
		this specified memory area will get subtracted from the top
		(end) of RAM and won't get "touched" at all by U-Boot. By
		fixing up gd->ram_size the Linux kernel should gets passed
		the now "corrected" memory size and won't touch it either.
		This should work for arch/ppc and arch/powerpc. Only Linux
		board ports in arch/powerpc with bootwrapper support that
		recalculate the memory size from the SDRAM controller setup
		will have to get fixed in Linux additionally.

		This option can be used as a workaround for the 440EPx/GRx
		CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
		be touched.

		WARNING: Please make sure that this value is a multiple of
		the Linux page size (normally 4k). If this is not the case,
		then the end address of the Linux memory will be located at a
		non page size aligned address and this could cause major
		problems.

- CONFIG_SYS_LOADS_BAUD_CHANGE:
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		Enable temporary baudrate change while serial download

- CONFIG_SYS_SDRAM_BASE:
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		Physical start address of SDRAM. _Must_ be 0 here.

- CONFIG_SYS_FLASH_BASE:
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		Physical start address of Flash memory.

- CONFIG_SYS_MONITOR_BASE:
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		Physical start address of boot monitor code (set by
		make config files to be same as the text base address
		(CONFIG_SYS_TEXT_BASE) used when linking) - same as
		CONFIG_SYS_FLASH_BASE when booting from flash.
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- CONFIG_SYS_MONITOR_LEN:
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		Size of memory reserved for monitor code, used to
		determine _at_compile_time_ (!) if the environment is
		embedded within the U-Boot image, or in a separate
		flash sector.
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- CONFIG_SYS_MALLOC_LEN:
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		Size of DRAM reserved for malloc() use.

- CONFIG_SYS_MALLOC_F_LEN
		Size of the malloc() pool for use before relocation. If
		this is defined, then a very simple malloc() implementation
		will become available before relocation. The address is just
		below the global data, and the stack is moved down to make
		space.

		This feature allocates regions with increasing addresses
		within the region. calloc() is supported, but realloc()
		is not available. free() is supported but does nothing.
		The memory will be freed (or in fact just forgotten) when
- CONFIG_SYS_MALLOC_SIMPLE
		Provides a simple and small malloc() and calloc() for those
		boards which do not use the full malloc in SPL (which is
		enabled with CONFIG_SYS_SPL_MALLOC_START).

- CONFIG_SYS_NONCACHED_MEMORY:
		Size of non-cached memory area. This area of memory will be
		typically located right below the malloc() area and mapped
		uncached in the MMU. This is useful for drivers that would
		otherwise require a lot of explicit cache maintenance. For
		some drivers it's also impossible to properly maintain the
		cache. For example if the regions that need to be flushed
		are not a multiple of the cache-line size, *and* padding
		cannot be allocated between the regions to align them (i.e.
		if the HW requires a contiguous array of regions, and the
		size of each region is not cache-aligned), then a flush of
		one region may result in overwriting data that hardware has
		written to another region in the same cache-line. This can
		happen for example in network drivers where descriptors for
		buffers are typically smaller than the CPU cache-line (e.g.
		16 bytes vs. 32 or 64 bytes).

		Non-cached memory is only supported on 32-bit ARM at present.

- CONFIG_SYS_BOOTM_LEN:
		Normally compressed uImages are limited to an
		uncompressed size of 8 MBytes. If this is not enough,
		you can define CONFIG_SYS_BOOTM_LEN in your board config file
		to adjust this setting to your needs.

- CONFIG_SYS_BOOTMAPSZ:
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		Maximum size of memory mapped by the startup code of
		the Linux kernel; all data that must be processed by
		the Linux kernel (bd_info, boot arguments, FDT blob if
		used) must be put below this limit, unless "bootm_low"
		environment variable is defined and non-zero. In such case
		all data for the Linux kernel must be between "bootm_low"
		and "bootm_low" + CONFIG_SYS_BOOTMAPSZ.	 The environment
		variable "bootm_mapsize" will override the value of
		CONFIG_SYS_BOOTMAPSZ.  If CONFIG_SYS_BOOTMAPSZ is undefined,
		then the value in "bootm_size" will be used instead.
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- CONFIG_SYS_BOOT_RAMDISK_HIGH:
		Enable initrd_high functionality.  If defined then the
		initrd_high feature is enabled and the bootm ramdisk subcommand
		is enabled.

- CONFIG_SYS_BOOT_GET_CMDLINE:
		Enables allocating and saving kernel cmdline in space between
		"bootm_low" and "bootm_low" + BOOTMAPSZ.

- CONFIG_SYS_BOOT_GET_KBD:
		Enables allocating and saving a kernel copy of the bd_info in
		space between "bootm_low" and "bootm_low" + BOOTMAPSZ.

- CONFIG_SYS_MAX_FLASH_BANKS:
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		Max number of Flash memory banks

- CONFIG_SYS_MAX_FLASH_SECT:
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		Max number of sectors on a Flash chip

- CONFIG_SYS_FLASH_ERASE_TOUT:
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		Timeout for Flash erase operations (in ms)

- CONFIG_SYS_FLASH_WRITE_TOUT:
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		Timeout for Flash write operations (in ms)

- CONFIG_SYS_FLASH_LOCK_TOUT
		Timeout for Flash set sector lock bit operation (in ms)

- CONFIG_SYS_FLASH_UNLOCK_TOUT
		Timeout for Flash clear lock bits operation (in ms)

- CONFIG_SYS_FLASH_PROTECTION
		If defined, hardware flash sectors protection is used
		instead of U-Boot software protection.

- CONFIG_SYS_DIRECT_FLASH_TFTP:
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		Enable TFTP transfers directly to flash memory;
		without this option such a download has to be
		performed in two steps: (1) download to RAM, and (2)
		copy from RAM to flash.

		The two-step approach is usually more reliable, since
		you can check if the download worked before you erase
		the flash, but in some situations (when system RAM is
		too limited to allow for a temporary copy of the
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		downloaded image) this option may be very useful.

- CONFIG_SYS_FLASH_CFI:
		Define if the flash driver uses extra elements in the
		common flash structure for storing flash geometry.

		This option also enables the building of the cfi_flash driver
		in the drivers directory
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- CONFIG_FLASH_CFI_MTD
		This option enables the building of the cfi_mtd driver
		in the drivers directory. The driver exports CFI flash
		to the MTD layer.

- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
		Use buffered writes to flash.

- CONFIG_FLASH_SPANSION_S29WS_N
		s29ws-n MirrorBit flash has non-standard addresses for buffered
		write commands.

- CONFIG_SYS_FLASH_QUIET_TEST
		If this option is defined, the common CFI flash doesn't
		print it's warning upon not recognized FLASH banks. This
		is useful, if some of the configured banks are only
		optionally available.

- CONFIG_FLASH_SHOW_PROGRESS
		If defined (must be an integer), print out countdown
		digits and dots.  Recommended value: 45 (9..1) for 80
		column displays, 15 (3..1) for 40 column displays.

- CONFIG_FLASH_VERIFY
		If defined, the content of the flash (destination) is compared
		against the source after the write operation. An error message
		will be printed when the contents are not identical.
		Please note that this option is useless in nearly all cases,
		since such flash programming errors usually are detected earlier
		while unprotecting/erasing/programming. Please only enable
		this option if you really know what you are doing.

- CONFIG_SYS_RX_ETH_BUFFER:
		Defines the number of Ethernet receive buffers. On some
		Ethernet controllers it is recommended to set this value
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		to 8 or even higher (EEPRO100 or 405 EMAC), since all
		buffers can be full shortly after enabling the interface
		on high Ethernet traffic.
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		Defaults to 4 if not defined.

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	Maximum number of entries in the hash table that is used
	internally to store the environment settings. The default
	setting is supposed to be generous and should work in most
	cases. This setting can be used to tune behaviour; see
	lib/hashtable.c for details.
- CONFIG_ENV_FLAGS_LIST_DEFAULT
- CONFIG_ENV_FLAGS_LIST_STATIC
	Enable validation of the values given to environment variables when
	calling env set.  Variables can be restricted to only decimal,
	hexadecimal, or boolean.  If CONFIG_CMD_NET is also defined,
	the variables can also be restricted to IP address or MAC address.

	The format of the list is:
		type_attribute = [s|d|x|b|i|m]
		access_attribute = [a|r|o|c]
		attributes = type_attribute[access_attribute]
		entry = variable_name[:attributes]
		list = entry[,list]

	The type attributes are:
		s - String (default)
		d - Decimal
		x - Hexadecimal
		b - Boolean ([1yYtT|0nNfF])
		i - IP address
		m - MAC address

	The access attributes are:
		a - Any (default)
		r - Read-only
		o - Write-once
		c - Change-default

	- CONFIG_ENV_FLAGS_LIST_DEFAULT
		Define this to a list (string) to define the ".flags"
		environment variable in the default or embedded environment.

	- CONFIG_ENV_FLAGS_LIST_STATIC
		Define this to a list (string) to define validation that
		should be done if an entry is not found in the ".flags"
		environment variable.  To override a setting in the static
		list, simply add an entry for the same variable name to the
		".flags" variable.

	If CONFIG_REGEX is defined, the variable_name above is evaluated as a
	regular expression. This allows multiple variables to define the same
	flags without explicitly listing them for each variable.

- CONFIG_ENV_ACCESS_IGNORE_FORCE
	If defined, don't allow the -f switch to env set override variable
	access flags.

- CONFIG_USE_STDINT
	If stdint.h is available with your toolchain you can define this
	option to enable it. You can provide option 'USE_STDINT=1' when
	building U-Boot to enable this.

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The following definitions that deal with the placement and management
of environment data (variable area); in general, we support the
following configurations:

- CONFIG_BUILD_ENVCRC:

	Builds up envcrc with the target environment so that external utils
	may easily extract it and embed it in final U-Boot images.

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BE CAREFUL! The first access to the environment happens quite early
in U-Boot initialization (when we try to get the setting of for the
console baudrate). You *MUST* have mapped your NVRAM area then, or
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U-Boot will hang.

Please note that even with NVRAM we still use a copy of the
environment in RAM: we could work on NVRAM directly, but we want to
keep settings there always unmodified except somebody uses "saveenv"
to save the current settings.

BE CAREFUL! For some special cases, the local device can not use
"saveenv" command. For example, the local device will get the
environment stored in a remote NOR flash by SRIO or PCIE link,
but it can not erase, write this NOR flash by SRIO or PCIE interface.
- CONFIG_NAND_ENV_DST

	Defines address in RAM to which the nand_spl code should copy the
	environment. If redundant environment is used, it will be copied to
	CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.

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Please note that the environment is read-only until the monitor
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has been relocated to RAM and a RAM copy of the environment has been
created; also, when using EEPROM you will have to use getenv_f()
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until then to read environment variables.

The environment is protected by a CRC32 checksum. Before the monitor
is relocated into RAM, as a result of a bad CRC you will be working
with the compiled-in default environment - *silently*!!! [This is
necessary, because the first environment variable we need is the
"baudrate" setting for the console - if we have a bad CRC, we don't
have any device yet where we could complain.]
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Note: once the monitor has been relocated, then it will complain if
the default environment is used; a new CRC is computed as soon as you
use the "saveenv" command to store a valid environment.
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- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
		Echo the inverted Ethernet link state to the fault LED.
		Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
		      also needs to be defined.

- CONFIG_SYS_FAULT_MII_ADDR:
		MII address of the PHY to check for the Ethernet link state.
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- CONFIG_NS16550_MIN_FUNCTIONS:
		Define this if you desire to only have use of the NS16550_init
		and NS16550_putc functions for the serial driver located at
		drivers/serial/ns16550.c.  This option is useful for saving
		space for already greatly restricted images, including but not
		limited to NAND_SPL configurations.

- CONFIG_DISPLAY_BOARDINFO
		Display information about the board that U-Boot is running on
		when U-Boot starts up. The board function checkboard() is called
		to do this.

- CONFIG_DISPLAY_BOARDINFO_LATE
		Similar to the previous option, but display this information
		later, once stdio is running and output goes to the LCD, if
		present.

- CONFIG_BOARD_SIZE_LIMIT:
		Maximum size of the U-Boot image. When defined, the
		build system checks that the actual size does not
		exceed it.

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Low Level (hardware related) configuration options:
---------------------------------------------------
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- CONFIG_SYS_CACHELINE_SIZE:
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		Cache Line Size of the CPU.

- CONFIG_SYS_CCSRBAR_DEFAULT:
		Default (power-on reset) physical address of CCSR on Freescale
		PowerPC SOCs.

- CONFIG_SYS_CCSRBAR:
		Virtual address of CCSR.  On a 32-bit build, this is typically
		the same value as CONFIG_SYS_CCSRBAR_DEFAULT.

- CONFIG_SYS_CCSRBAR_PHYS:
		Physical address of CCSR.  CCSR can be relocated to a new
		physical address, if desired.  In this case, this macro should
		be set to that address.	 Otherwise, it should be set to the
		same value as CONFIG_SYS_CCSRBAR_DEFAULT.  For example, CCSR
		is typically relocated on 36-bit builds.  It is recommended
		that this macro be defined via the _HIGH and _LOW macros:

		#define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
			* 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)

- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
		Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS.	This value is typically
		either 0 (32-bit build) or 0xF (36-bit build).	This macro is
		used in assembly code, so it must not contain typecasts or
		integer size suffixes (e.g. "ULL").

- CONFIG_SYS_CCSRBAR_PHYS_LOW:
		Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS.  This macro is
		used in assembly code, so it must not contain typecasts or
		integer size suffixes (e.g. "ULL").

- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
		If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
		forced to a value that ensures that CCSR is not relocated.

- Floppy Disk Support:
		CONFIG_SYS_FDC_DRIVE_NUMBER

		the default drive number (default value 0)

		CONFIG_SYS_ISA_IO_STRIDE
		defines the spacing between FDC chipset registers
		(default value 1)

		CONFIG_SYS_ISA_IO_OFFSET
		defines the offset of register from address. It
		depends on which part of the data bus is connected to
		the FDC chipset. (default value 0)
		If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
		CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
		default value.
		if CONFIG_SYS_FDC_HW_INIT is defined, then the function
		fdc_hw_init() is called at the beginning of the FDC
		setup. fdc_hw_init() must be provided by the board
		source code. It is used to make hardware-dependent
		initializations.
- CONFIG_IDE_AHB:
		Most IDE controllers were designed to be connected with PCI
		interface. Only few of them were designed for AHB interface.
		When software is doing ATA command and data transfer to
		IDE devices through IDE-AHB controller, some additional
		registers accessing to these kind of IDE-AHB controller
- CONFIG_SYS_IMMR:	Physical address of the Internal Memory.
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		DO NOT CHANGE unless you know exactly what you're
		doing! (11-4) [MPC8xx systems only]
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- CONFIG_SYS_INIT_RAM_ADDR:
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		Start address of memory area that can be used for
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		initial data and stack; please note that this must be
		writable memory that is working WITHOUT special
		initialization, i. e. you CANNOT use normal RAM which
		will become available only after programming the
		memory controller and running certain initialization
		sequences.

		U-Boot uses the following memory types:
		- MPC8xx: IMMR (internal memory of the CPU)
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- CONFIG_SYS_GBL_DATA_OFFSET:
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		Offset of the initial data structure in the memory
		area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
		CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
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		data is located at the end of the available space
		(sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
		GENERATED_GBL_DATA_SIZE), and the initial stack is just
		below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
		CONFIG_SYS_GBL_DATA_OFFSET) downward.
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	Note:
		On the MPC824X (or other systems that use the data
		cache for initial memory) the address chosen for
		CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
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		point to an otherwise UNUSED address space between
		the top of RAM and the start of the PCI space.

- CONFIG_SYS_SCCR:	System Clock and reset Control Register (15-27)
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- CONFIG_SYS_OR_TIMING_SDRAM:
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		SDRAM timing

- CONFIG_SYS_MAMR_PTA:
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		periodic timer for refresh

- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
  CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
  CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
  CONFIG_SYS_BR1_PRELIM:
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		Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)

- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
  CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
  CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
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		Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)

		Only scan through and get the devices on the buses.
		Don't do any setup work, presumably because someone or
		something has already done it, and we don't need to do it
		a second time.	Useful for platforms that are pre-booted
		by coreboot or similar.

- CONFIG_PCI_INDIRECT_BRIDGE:
		Enable support for indirect PCI bridges.

- CONFIG_SYS_SRIO:
		Chip has SRIO or not

- CONFIG_SRIO1:
		Board has SRIO 1 port available

- CONFIG_SRIO2:
		Board has SRIO 2 port available

- CONFIG_SRIO_PCIE_BOOT_MASTER
		Board can support master function for Boot from SRIO and PCIE

- CONFIG_SYS_SRIOn_MEM_VIRT:
		Virtual Address of SRIO port 'n' memory region

- CONFIG_SYS_SRIOn_MEM_PHYS:
		Physical Address of SRIO port 'n' memory region

- CONFIG_SYS_SRIOn_MEM_SIZE:
		Size of SRIO port 'n' memory region

- CONFIG_SYS_NAND_BUSWIDTH_16BIT
		Defined to tell the NAND controller that the NAND chip is using
		a 16 bit bus.
		Not all NAND drivers use this symbol.
		Example of drivers that use it:
		- drivers/mtd/nand/ndfc.c
		- drivers/mtd/nand/mxc_nand.c

- CONFIG_SYS_NDFC_EBC0_CFG
		Sets the EBC0_CFG register for the NDFC. If not defined
		a default value will be used.

- CONFIG_SPD_EEPROM
		Get DDR timing information from an I2C EEPROM. Common
		with pluggable memory modules such as SODIMMs

  SPD_EEPROM_ADDRESS
		I2C address of the SPD EEPROM

- CONFIG_SYS_SPD_BUS_NUM
		If SPD EEPROM is on an I2C bus other than the first
		one, specify here. Note that the value must resolve
		to something your driver can deal with.
- CONFIG_SYS_DDR_RAW_TIMING
		Get DDR timing information from other than SPD. Common with
		soldered DDR chips onboard without SPD. DDR raw timing
		parameters are extracted from datasheet and hard-coded into
		header files or board specific files.

- CONFIG_FSL_DDR_INTERACTIVE
		Enable interactive DDR debugging. See doc/README.fsl-ddr.

- CONFIG_FSL_DDR_SYNC_REFRESH
		Enable sync of refresh for multiple controllers.

- CONFIG_FSL_DDR_BIST
		Enable built-in memory test for Freescale DDR controllers.

- CONFIG_SYS_83XX_DDR_USES_CS0
		Only for 83xx systems. If specified, then DDR should
		be configured using CS0 and CS1 instead of CS2 and CS3.
- CONFIG_RMII
		Enable RMII mode for all FECs.
		Note that this is a global option, we can't
		have one FEC in standard MII mode and another in RMII mode.

- CONFIG_CRC32_VERIFY
		Add a verify option to the crc32 command.
		The syntax is:

		=> crc32 -v <address> <count> <crc32>

		Where address/count indicate a memory area
		and crc32 is the correct crc32 which the
		area should have.

- CONFIG_LOOPW
		Add the "loopw" memory command. This only takes effect if
		the memory commands are activated globally (CONFIG_CMD_MEM).
- CONFIG_MX_CYCLIC
		Add the "mdc" and "mwc" memory commands. These are cyclic
		"md/mw" commands.
		Examples:

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		=> mdc.b 10 4 500
		This command will print 4 bytes (10,11,12,13) each 500 ms.

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		=> mwc.l 100 12345678 10
		This command will write 12345678 to address 100 all 10 ms.

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		This only takes effect if the memory commands are activated
- CONFIG_SKIP_LOWLEVEL_INIT
		[ARM, NDS32, MIPS only] If this variable is defined, then certain
		low level initializations (like setting up the memory
		controller) are omitted and/or U-Boot does not
		relocate itself into RAM.

		Normally this variable MUST NOT be defined. The only
		exception is when U-Boot is loaded (to RAM) by some
		other boot loader or by a debugger which performs
		these initializations itself.
- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
		[ARM926EJ-S only] This allows just the call to lowlevel_init()
		to be skipped. The normal CP15 init (such as enabling the
		instruction cache) is still performed.

- CONFIG_SPL_BUILD
		Modifies the behaviour of start.S when compiling a loader
		that is executed before the actual U-Boot. E.g. when
		compiling a NAND SPL.
- CONFIG_TPL_BUILD
		Modifies the behaviour of start.S  when compiling a loader
		that is executed after the SPL and before the actual U-Boot.
		It is loaded by the SPL.

- CONFIG_SYS_MPC85XX_NO_RESETVEC
		Only for 85xx systems. If this variable is specified, the section
		.resetvec is not kept and the section .bootpg is placed in the
		previous 4k of the .text section.

- CONFIG_ARCH_MAP_SYSMEM
		Generally U-Boot (and in particular the md command) uses
		effective address. It is therefore not necessary to regard
		U-Boot address as virtual addresses that need to be translated
		to physical addresses. However, sandbox requires this, since
		it maintains its own little RAM buffer which contains all
		addressable memory. This option causes some memory accesses
		to be mapped through map_sysmem() / unmap_sysmem().

- CONFIG_X86_RESET_VECTOR
		If defined, the x86 reset vector code is included. This is not
		needed when U-Boot is running from Coreboot.
- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
		Enables the RTC32K OSC on AM33xx based plattforms

- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
		Option to disable subpage write in NAND driver
		driver that uses this:
		drivers/mtd/nand/davinci_nand.c

Freescale QE/FMAN Firmware Support:
-----------------------------------

The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
loading of "firmware", which is encoded in the QE firmware binary format.
This firmware often needs to be loaded during U-Boot booting, so macros
are used to identify the storage device (NOR flash, SPI, etc) and the address
within that device.

- CONFIG_SYS_FMAN_FW_ADDR
	The address in the storage device where the FMAN microcode is located.  The
	meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
	is also specified.

- CONFIG_SYS_QE_FW_ADDR
	The address in the storage device where the QE microcode is located.  The
	meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
	is also specified.

- CONFIG_SYS_QE_FMAN_FW_LENGTH
	The maximum possible size of the firmware.  The firmware binary format
	has a field that specifies the actual size of the firmware, but it
	might not be possible to read any part of the firmware unless some
	local storage is allocated to hold the entire firmware first.

- CONFIG_SYS_QE_FMAN_FW_IN_NOR
	Specifies that QE/FMAN firmware is located in NOR flash, mapped as
	normal addressable memory via the LBC.  CONFIG_SYS_FMAN_FW_ADDR is the
	virtual address in NOR flash.

- CONFIG_SYS_QE_FMAN_FW_IN_NAND
	Specifies that QE/FMAN firmware is located in NAND flash.
	CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.

- CONFIG_SYS_QE_FMAN_FW_IN_MMC
	Specifies that QE/FMAN firmware is located on the primary SD/MMC
	device.  CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.

- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
	Specifies that QE/FMAN firmware is located in the remote (master)
	memory space.	CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
	can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
	window->master inbound window->master LAW->the ucode address in
	master's memory space.
Freescale Layerscape Management Complex Firmware Support:
---------------------------------------------------------
The Freescale Layerscape Management Complex (MC) supports the loading of
"firmware".
This firmware often needs to be loaded during U-Boot booting, so macros
are used to identify the storage device (NOR flash, SPI, etc) and the address
within that device.

- CONFIG_FSL_MC_ENET
	Enable the MC driver for Layerscape SoCs.

Freescale Layerscape Debug Server Support:
-------------------------------------------
The Freescale Layerscape Debug Server Support supports the loading of
"Debug Server firmware" and triggering SP boot-rom.
This firmware often needs to be loaded during U-Boot booting.

- CONFIG_SYS_MC_RSV_MEM_ALIGN
	Define alignment of reserved memory MC requires
Reproducible builds
-------------------

In order to achieve reproducible builds, timestamps used in the U-Boot build
process have to be set to a fixed value.

This is done using the SOURCE_DATE_EPOCH environment variable.
SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
option for U-Boot or an environment variable in U-Boot.

SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.

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Building the Software:
======================

Building U-Boot has been tested in several native build environments
and in many different cross environments. Of course we cannot support
all possibly existing versions of cross development tools in all
(potentially obsolete) versions. In case of tool chain problems we
recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
which is extensively used to build and test U-Boot.
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If you are not using a native environment, it is assumed that you
have GNU cross compiling tools available in your path. In this case,
you must set the environment variable CROSS_COMPILE in your shell.
Note that no changes to the Makefile or any other source files are
necessary. For example using the ELDK on a 4xx CPU, please enter:
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	$ CROSS_COMPILE=ppc_4xx-
	$ export CROSS_COMPILE
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Note: If you wish to generate Windows versions of the utilities in
      the tools directory you can use the MinGW toolchain
      (http://www.mingw.org).  Set your HOST tools to the MinGW
      toolchain and execute 'make tools'.  For example:

       $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools

      Binaries such as tools/mkimage.exe will be created which can
      be executed on computers running Windows.

U-Boot is intended to be simple to build. After installing the
sources you must configure U-Boot for one specific board type. This
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is done by typing:

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where "NAME_defconfig" is the name of one of the existing configu-
rations; see boards.cfg for supported names.
Note: for some board special configuration names may exist; check if
      additional information is available from the board vendor; for
      instance, the TQM823L systems are available without (standard)
      or with LCD support. You can select such additional "features"
      when choosing the configuration, i. e.
	- will configure for a plain TQM823L, i. e. no LCD support

	- will configure for a TQM823L with U-Boot console on LCD

      etc.


Finally, type "make all", and you should get some working U-Boot
images ready for download to / installation on your system:

- "u-boot.bin" is a raw binary image
- "u-boot" is an image in ELF binary format
- "u-boot.srec" is in Motorola S-Record format

By default the build is performed locally and the objects are saved
in the source directory. One of the two methods can be used to change
this behavior and build U-Boot to some external directory:

1. Add O= to the make command line invocations:

	make O=/tmp/build distclean
2. Set environment variable KBUILD_OUTPUT to point to the desired location:
	export KBUILD_OUTPUT=/tmp/build
Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment

Please be aware that the Makefiles assume you are using GNU make, so
for instance on NetBSD you might need to use "gmake" instead of
native "make".


If the system board that you have is not listed, then you will need
to port U-Boot to your hardware platform. To do this, follow these
steps:

1.  Create a new directory to hold your board specific code. Add any
    files you need. In your board directory, you will need at least
    the "Makefile" and a "<board>.c".
2.  Create a new configuration file "include/configs/<board>.h" for
    your board.
3.  If you're porting U-Boot to a new CPU, then also create a new
    directory to hold your CPU specific code. Add any files you need.
4.  Run "make <board>_defconfig" with your new name.
5.  Type "make", and you should get a working "u-boot.srec" file
    to be installed on your target system.
6.  Debug and solve any problems that might arise.
    [Of course, this last step is much harder than it sounds.]


Testing of U-Boot Modifications, Ports to New Hardware, etc.:
==============================================================

If you have modified U-Boot sources (for instance added a new board
or support for new devices, a new CPU, etc.) you are expected to
provide feedback to the other developers. The feedback normally takes
the form of a "patch", i. e. a context diff against a certain (latest
official or latest in the git repository) version of U-Boot sources.
But before you submit such a patch, please verify that your modifi-
cation did not break existing code. At least make sure that *ALL* of
the supported boards compile WITHOUT ANY compiler warnings. To do so,
just run the buildman script (tools/buildman/buildman), which will
configure and build U-Boot for ALL supported system. Be warned, this
will take a while. Please see the buildman README, or run 'buildman -H'
for documentation.
See also "U-Boot Porting Guide" below.


Monitor Commands - Overview:
============================

go	- start application at address 'addr'
run	- run commands in an environment variable
bootm	- boot application image from memory
bootp	- boot image via network using BootP/TFTP protocol
bootz   - boot zImage from memory
tftpboot- boot image via network using TFTP protocol
	       and env variables "ipaddr" and "serverip"
	       (and eventually "gatewayip")
tftpput - upload a file via network using TFTP protocol
rarpboot- boot image via network using RARP/TFTP protocol
diskboot- boot from IDE devicebootd   - boot default, i.e., run 'bootcmd'
loads	- load S-Record file over serial line
loadb	- load binary file over serial line (kermit mode)
md	- memory display
mm	- memory modify (auto-incrementing)
nm	- memory modify (constant address)
mw	- memory write (fill)
cp	- memory copy
cmp	- memory compare
crc32	- checksum calculation
i2c	- I2C sub-system
sspi	- SPI utility commands
base	- print or set address offset
printenv- print environment variables
setenv	- set environment variables
saveenv - save environment variables to persistent storage
protect - enable or disable FLASH write protection
erase	- erase FLASH memory
flinfo	- print FLASH memory information
nand	- NAND memory operations (see doc/README.nand)
bdinfo	- print Board Info structure
iminfo	- print header information for application image