MiSTer u-boot script

u-boot_MiSTer/include/configs/socfpga_de10_nano.h
https://github.com/MiSTer-devel/u-boot_MiSTer/blob/MiSTer/include/configs/socfpga_de10_nano.h
# Annotated environment parameters for MiSTer platform U-Boot
# u-boot_MiSTer/include/configs/socfpga_de10_nano.h
# URL: https://github.com/MiSTer-devel/u-boot_MiSTer/blob/MiSTer/include/configs/socfpga_de10_nano.h

# Commands executed on preboot stage. Start USB PHY.
preboot=usb start

# CONFIG_SYS_LOAD_ADDR = CONFIG_LOADADDR = 0x01000000 (as defined in /include/configs/socfpga_de10_nano.h)
loadaddr=" __stringify(CONFIG_SYS_LOAD_ADDR) "

# Load compressed Linux kernel from /boot/zImage
bootimage=zImage

# Set address for FDT (Flat device tree) to 100(0x00000064) and set device tree image file to /boot/socfpga.dtb
# See more: https://www.denx.de/wiki/DULG/UBootCmdFDT
fdt_addr=100
fdtimage=socfpga.dtb

# Load FPGA binary to address 0x02000000. Set FPGA core name as menu.rbf (It will be loaded from )
fpgadata=0x02000000
core=menu.rbf

# Check FPGA state procedure
# 1. If TSTSCRATCH (0xFFD05054) register contains zero (Cold reset was made), then call loading FPGA image data procedure
# 2. Otherwise (warm reset case)
# 2.1 Check for 4 bytes signature 0x87654321(12345678) is found in memory on address 0x1FFFF000. That means extra env block was loaded from file.
# 2.2 If such block found, load extra env settings starting from address 0x1FFFF004 (skipping 4 signature bytes)
# 2.3 Call loading FPGA image data procedure
fpgacheck=if mt 0xFFD05054 0;then run fpgaload;else if mt 0x1FFFF000 0x87654321;then env import 0x1FFFF004;run fpgaload;fi;fi

# Procedure 'fpgaload'
# 1. Load FPGA image from file on MMC Boot (/boot/menu.rbf)
fpgaload=load mmc 0:$mmc_boot $fpgadata $core;fpga load 0 $fpgadata $filesize;bridge enable;mw 0x1FFFF000 0;mw 0xFFD05054 0x12345678

scrload1=load mmc 0:$mmc_boot $loadaddr u-boot.scr;source $loadaddr
scrload2=load mmc 0:$mmc_os $loadaddr u-boot.scr;source $loadaddr

# If MMC Boot location contains u-boot.scr file - load and execute it
scrtest=if test -e mmc 0:$mmc_boot /u-boot.scr;then run scrload1;fi;

# If MMC OS location contains u-boot.scr file - load and execute it
if test -e mmc 0:$mmc_os /u-boot.scr;then run scrload2;fi

# Set Ethernet address to 02:03:04:05:06:07
ethaddr=02:03:04:05:06:07

# Boot application image from memory
# arg1 = $loadaddr - Linux image address in memory
# arg2 = - (dash) - No initrd ramdisk image should be used
# arg3 = $fdt_addr - Address of Flat device tree BLOB loaded into memory
# See more: https://www.denx.de/wiki/DULG/UBootCmdGroupExec
bootm $loadaddr - $fdt_addr

# Define partition index (in SD card MBR) for:
# MMC Boot partition. mmc_boot = 1
# MMC OS partition mmc_os = 2
# MMC root path (MMC block device partition) mmc_root = /dev/mmcblk0p2
mmc_boot=" __stringify(CONFIG_SYS_MMCSD_FS_BOOT_PARTITION) "
mmc_os=" __stringify(CONFIG_SYS_MMCSD_FS_OS_PARTITION) "
mmcroot=/dev/mmcblk0p" __stringify(CONFIG_SYS_MMCSD_FS_OS_PARTITION) "

# Set loglevel to 4 (default_loglevel = 4). That means that no messages will be logged.
v=loglevel=4


mmcboot=setenv bootargs " CONFIG_BOOTARGS " root=$mmcroot ro rootwait;" "bootz $loadaddr - $fdt_addr
mmcload=mmc rescan;

run fpgacheck;
run scrtest;

# Load zImage and socfpga.dtb into memory on specified addresses
# zImage -> 0x
# socfpga.dtb -> 0x00000064
load mmc 0:$mmc_os $loadaddr /boot/$bootimage;

load mmc 0:$mmc_os $fdt_addr /boot/$fdtimage