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## SECTION=bootloader
menuconfig AT91BOOTSTRAP2
tristate
prompt "AT91 bootstrap 2.x "
help
Note: this is for AT91 bootstrap version 2.x
The AT91Bootstrap application is a first level bootloader
for Atmel AT91SAM9 ARM Thumb-based microcontrollers.
It is used for booting these microcontrollers from SPI dataflash
or NAND-flash.
For example, using this bootstrap, it is possible to
obtain a basic bootloader that is located in DataFlash and is
copied to internal SRAM by SAM-BA Boot (internal bootROM). The
bootloader performs the processor initialization (PLLs, PIOs,
SDRAMC, SPI), loads UBoot from DataFlash sectors to SDRAM and
then jumps to it.
It is required for these microcontrollers, because the bootROM of some
of these cores can only handle a miximum of 4kB of the 1st stage
bootloader (e.g. SRAM limits). U-boot is usually much larger
than this.
U-boot is normally build with the options CONFIG_SKIP_LOWLEVEL_INIT
and CONFIG_SKIP_RELOCATE_UBOOT
AT91Bootstrap integrates several sets of algorithms:
- Device initialization such as clock speed configuration, PIO settings, etc.
- Peripheral drivers such as PIO, PMC, SDRAMC, etc.
- Physical media algorithms such as DataFlash, NANDFlash, Parallel Flash, etc.
if AT91BOOTSTRAP2
config AT91BOOTSTRAP2_VERSION
string
default "2.13"
prompt "AT91 Bootstrap version"
help
Enter the AT91 Bootstrap version you want to build. Usally something like "1.11"
config AT91BOOTSTRAP2_MD5
prompt "AT91 Bootstrap source md5sum"
string
config AT91BOOTSTRAP2_CONFIG
prompt "config file"
string
default "at91bootstrap.config"
help
This entry specifies the .config file used to compile
at91bootstrap.
endif
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