User:Brendlefly62/Rockchip RK3288 Asus Tinker Board S/Build-Install-U-Boot/DIY u-boot

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Warning
This procedure is under development -- it doesn't work yet, for this board

DIY Prerequisites

The outline below is a work in progress - attempt to document how to build a working u-boot bootloader from scratch. The documentation below is very rough draft and DOES NOT WORK. U-Boot can be built on an ARM device or cross-compiled on a PC. Regardless, we will need:

  • git, to check out the sources
  • dtc, to compile device trees
  • swig, to build U-Boot
  • crossdev, since a 32-bit ARM toolchain is required

Let's make sure these are installed:

root #emerge --ask --update dev-vcs/git sys-apps/dtc dev-lang/swig sys-devel/crossdev

Please review the crossdev article if you don't already have it set up.

You may need to install the 32-bit toolchain, which is required to build code for Cortex-M0 MCUs in BL31:

root #crossdev --target arm-none-eabi

If cross-compiling, install the 64-bit cross-compiler toolchain:

root #crossdev --target armv7a-unknown-linux-gnueabihf


Compiling

To compile on ARM run commands like:

user $make -j$(nproc) PLAT=rk3288 <target>

If cross-compiling, run:

user $make -j$(nproc) PLAT=rk3288 CROSS_COMPILE=armv7a-unknown-linux-gnueabihf- <target>

If running distcc on the cross-compiling platform, it may be wise/necessary to disable that by temporarily removing '/usr/lib/distcc/bin' from your $PATH and turning off distcc in $FEATURES

user $export PATH=$(echo $PATH | sed 's|/usr/lib/distcc/bin:||')
user $MAKEOPTS="-j$(nproc) -l$(nproc)" FEATURES=$FEATURES" -distcc -distcc-pump" PLAT=rk3288 CROSS_COMPILE=armv7a-unknown-linux-gnueabihf- <target>

For Arm64 platforms, there is another pre-requisite step of building Arm Trusted Firmware "bl31" file, but as of Nov. 2023, the ATF Makefile says, "bl31 is not currently supported for aarch32.

Boot Loader alternatives

There are a number of ways to do this. This article describes one way to build a boot loader for TinkerBoard S using Arm Trusted Firmware (ATF or TF-A) and Das U-Boot. For detailed information on other methods, see link in the external resources and references secions, below.

Prepare to Build ATF

user $cd arm-trusted-firmware
user $git tag
...
v2.9.0

Select the latest currently stable version:

user $git checkout v2.9.0

The repository contains a few binaries. If this is unacceptable, they may be deleted:

user $for x in $(find ./ -iname *.bin); do rm -v $x; done
user $git status
,,,
        deleted:    plat/arm/board/common/protpk/arm_protpk_rsa_sha256.bin
        deleted:    plat/arm/board/common/rotpk/arm_rotpk_ecdsa_sha256.bin
        deleted:    plat/arm/board/common/rotpk/arm_rotpk_rsa_sha256.bin
        deleted:    plat/arm/board/common/swd_rotpk/arm_swd_rotpk_rsa_sha256.bin
        deleted:    plat/rockchip/rk3368/drivers/ddr/rk3368_ddr_reg_resume_V1.05.bin
        deleted:    plat/rockchip/rk3399/drivers/dp/hdcp.bin
...

Per the ATF "How to Build" instructions,[1] compile (using an appropriately formatted command [see above]) the bl32 file that this board's u-boot will expect. According to the TF-A users guide, using the targets "all fip" will generate all of the bootloader binaries and a firmware information package (fip.bin) --

user $MAKEOPTS="-j4 -l4" FEATURES=" -userpriv -distcc -distcc-pump" make ARCH=aarch32 PLAT=rk3288 CROSS_COMPILE=armv7a-unknown-linux-gnueabihf- AARCH32_SP=sp_min all fip
Including bl32/sp_min/sp_min.mk
  CC      lib/libfdt/fdt.c
  CC      lib/libfdt/fdt_addresses.c
  CC      lib/libfdt/fdt_empty_tree.c
  CC      lib/libfdt/fdt_ro.c
  CC      lib/libfdt/fdt_rw.c
  CC      lib/libfdt/fdt_strerror.c
  CC      lib/libfdt/fdt_sw.c
  CC      lib/libfdt/fdt_wip.c
  AR      /home/joe/MyTinkerboardFiles/arm-trusted-firmware/build/rk3288/release/lib/libfdt.a
Building rk3288
  CC      lib/libc/abort.c
  CC      lib/libc/assert.c
  CC      lib/libc/exit.c
  CC      lib/libc/memchr.c
  CC      lib/libc/memcmp.c
  CC      lib/libc/memcpy.c
  CC      lib/libc/memmove.c
  CC      lib/libc/memrchr.c
  CC      lib/libc/memset.c
  CC      lib/libc/printf.c
  CC      lib/libc/putchar.c
  CC      lib/libc/puts.c
  CC      lib/libc/snprintf.c
  CC      lib/libc/strchr.c
  CC      lib/libc/strcmp.c
  CC      lib/libc/strlcat.c
  CC      lib/libc/strlcpy.c
  CC      lib/libc/strlen.c
  CC      lib/libc/strncmp.c
  CC      lib/libc/strnlen.c
  CC      lib/libc/strrchr.c
  CC      lib/libc/strtok.c
  CC      lib/libc/strtoul.c
  CC      lib/libc/strtoll.c
  CC      lib/libc/strtoull.c
  CC      lib/libc/strtol.c
  AR      /home/joe/MyTinkerboardFiles/arm-trusted-firmware/build/rk3288/release/lib/libc.a
  CC      bl32/sp_min/sp_min_main.c
  CC      common/runtime_svc.c
  CC      drivers/arm/cci/cci.c
  CC      drivers/arm/gic/v2/gicdv2_helpers.c
  CC      drivers/arm/gic/v2/gicv2_helpers.c
  CC      drivers/arm/gic/v2/gicv2_main.c
  CC      drivers/delay_timer/delay_timer.c
  CC      drivers/delay_timer/generic_delay_timer.c
  CC      lib/cpus/errata_report.c
  CC      lib/el3_runtime/aarch32/context_mgmt.c
  CC      lib/el3_runtime/cpu_data_array.c
  CC      lib/locks/bakery/bakery_lock_coherent.c
  CC      lib/psci/psci_common.c
  CC      lib/psci/psci_main.c
  CC      lib/psci/psci_mem_protect.c
  CC      lib/psci/psci_off.c
  CC      lib/psci/psci_on.c
  CC      lib/psci/psci_setup.c
  CC      lib/psci/psci_suspend.c
  CC      lib/psci/psci_system_off.c
  CC      plat/common/aarch32/plat_sp_min_common.c
  CC      plat/common/plat_gicv2.c
  CC      plat/rockchip/common/aarch32/platform_common.c
  CC      plat/rockchip/common/params_setup.c
  CC      plat/rockchip/common/plat_pm.c
  CC      plat/rockchip/common/plat_topology.c
  CC      plat/rockchip/common/rockchip_gicv2.c
  CC      plat/rockchip/common/rockchip_sip_svc.c
  CC      plat/rockchip/common/sp_min_plat_setup.c
  CC      plat/rockchip/rk3288/drivers/pmu/pmu.c
  CC      plat/rockchip/rk3288/drivers/secure/secure.c
  CC      plat/rockchip/rk3288/drivers/soc/soc.c
  CC      plat/rockchip/rk3288/plat_sip_calls.c
  CC      services/std_svc/std_svc_setup.c
  CC      common/bl_common.c
  CC      common/tf_log.c
  CC      drivers/console/multi_console.c
  CC      plat/common/plat_bl_common.c
  CC      plat/common/plat_log_common.c
  CC      plat/common/aarch32/plat_common.c
  CC      lib/compiler-rt/builtins/popcountdi2.c
  CC      lib/compiler-rt/builtins/popcountsi2.c
  CC      lib/compiler-rt/builtins/ctzdi2.c
  CC      lib/compiler-rt/builtins/divdi3.c
  CC      lib/compiler-rt/builtins/divmoddi4.c
  CC      lib/compiler-rt/builtins/lshrdi3.c
  CC      lib/compiler-rt/builtins/udivmoddi4.c
  CC      common/desc_image_load.c
  CC      lib/bl_aux_params/bl_aux_params.c
  CC      plat/common/plat_psci_common.c
  CC      lib/xlat_tables/xlat_tables_common.c
  CC      lib/xlat_tables/aarch32/xlat_tables.c
  AS      bl32/sp_min/aarch32/entrypoint.S
  AS      bl32/sp_min/wa_cve_2017_5715_icache_inv.S
  AS      drivers/ti/uart/aarch32/16550_console.S
  AS      lib/cpus/aarch32/cortex_a12.S
  AS      lib/cpus/aarch32/cpu_helpers.S
  AS      lib/el3_runtime/aarch32/cpu_data.S
  AS      lib/locks/exclusive/aarch32/spinlock.S
  AS      lib/psci/aarch32/psci_helpers.S
  AS      plat/common/aarch32/platform_mp_stack.S
  AS      plat/rockchip/common/aarch32/plat_helpers.S
  AS      plat/rockchip/common/aarch32/pmu_sram_cpus_on.S
  AS      common/aarch32/debug.S
  AS      lib/aarch32/cache_helpers.S
  AS      lib/aarch32/misc_helpers.S
  AS      plat/common/aarch32/platform_helpers.S
  AS      lib/compiler-rt/builtins/arm/aeabi_ldivmod.S
  AS      lib/compiler-rt/builtins/arm/aeabi_uldivmod.S
  AS      lib/compiler-rt/builtins/arm/aeabi_memcpy.S
  AS      lib/compiler-rt/builtins/arm/aeabi_memset.S
  AS      plat/common/aarch32/crash_console_helpers.S
  PP      bl32/sp_min/sp_min.ld.S
  LD      /home/joe/MyTinkerboardFiles/arm-trusted-firmware/build/rk3288/release/bl32/bl32.elf

Built /home/joe/MyTinkerboardFiles/arm-trusted-firmware/build/rk3288/release/bl32/bl32.elf successfully

  OD      /home/joe/MyTinkerboardFiles/arm-trusted-firmware/build/rk3288/release/bl32/bl32.dump
  BIN     /home/joe/MyTinkerboardFiles/arm-trusted-firmware/build/rk3288/release/bl32.bin

Built /home/joe/MyTinkerboardFiles/arm-trusted-firmware/build/rk3288/release/bl32.bin successfully

  HOSTCC  fiptool.c
  HOSTCC  tbbr_config.c
  HOSTLD  fiptool
/usr/lib/gcc/x86_64-pc-linux-gnu/13/../../../../x86_64-pc-linux-gnu/bin/ld: skipping incompatible /usr/lib/libc.so when searching for -lc
/usr/lib/gcc/x86_64-pc-linux-gnu/13/../../../../x86_64-pc-linux-gnu/bin/ld: skipping incompatible /usr/lib/libc.a when searching for -lc

Built fiptool successfully


Secure Payload BL32 (Trusted OS): offset=0x60, size=0xFF6E0018, cmdline="--tos-fw"

Built /home/joe/MyTinkerboardFiles/arm-trusted-firmware/build/rk3288/release/fip.bin successfully

Locate the resulting bl32.elf --

user $find ./ -iname bl32.elf
./build/rk3288/release/bl32/bl32.elf

Note that the output files are stored in a "release" directory within a platform directory *"rk3288" inside the "build" sub-directory. The sturcture should look something like this

user $tree build
build/
`-- rk3288
    `-- release
        |-- bl32
        |   |-- 16550_console.d
        |   |-- 16550_console.o
        |   |-- aeabi_ldivmod.d
        |   |-- aeabi_ldivmod.o
        |   |-- aeabi_memcpy.d
        |   |-- aeabi_memcpy.o
        |   |-- aeabi_memset.d
        |   |-- aeabi_memset.o
        |   |-- aeabi_uldivmod.d
        |   |-- aeabi_uldivmod.o
        |   |-- bakery_lock_coherent.d
        |   |-- bakery_lock_coherent.o
        |   |-- bl32
        |   |   `-- sp_min
        |   |       |-- sp_min.ld
        |   |       `-- sp_min.ld.d
        |   |-- bl32.dump
        |   |-- bl32.elf
        |   |-- bl32.map
        |   |-- bl_aux_params.d
        |   |-- bl_aux_params.o
        |   |-- bl_common.d
        |   |-- bl_common.o
        |   |-- build_message.o
        |   |-- cache_helpers.d
        |   |-- cache_helpers.o
        |   |-- cci.d
        |   |-- cci.o
        |   |-- context_mgmt.d
        |   |-- context_mgmt.o
        |   |-- cortex_a12.d
        |   |-- cortex_a12.o
        |   |-- cpu_data.d
        |   |-- cpu_data.o
        |   |-- cpu_data_array.d
        |   |-- cpu_data_array.o
        |   |-- cpu_helpers.d
        |   |-- cpu_helpers.o
        |   |-- crash_console_helpers.d
        |   |-- crash_console_helpers.o
        |   |-- ctzdi2.d
        |   |-- ctzdi2.o
        |   |-- debug.d
        |   |-- debug.o
        |   |-- delay_timer.d
        |   |-- delay_timer.o
        |   |-- desc_image_load.d
        |   |-- desc_image_load.o
        |   |-- divdi3.d
        |   |-- divdi3.o
        |   |-- divmoddi4.d
        |   |-- divmoddi4.o
        |   |-- entrypoint.d
        |   |-- entrypoint.o
        |   |-- errata_report.d
        |   |-- errata_report.o
        |   |-- generic_delay_timer.d
        |   |-- generic_delay_timer.o
        |   |-- gicdv2_helpers.d
        |   |-- gicdv2_helpers.o
        |   |-- gicv2_helpers.d
        |   |-- gicv2_helpers.o
        |   |-- gicv2_main.d
        |   |-- gicv2_main.o
        |   |-- lshrdi3.d
        |   |-- lshrdi3.o
        |   |-- misc_helpers.d
        |   |-- misc_helpers.o
        |   |-- multi_console.d
        |   |-- multi_console.o
        |   |-- params_setup.d
        |   |-- params_setup.o
        |   |-- plat_bl_common.d
        |   |-- plat_bl_common.o
        |   |-- plat_common.d
        |   |-- plat_common.o
        |   |-- plat_gicv2.d
        |   |-- plat_gicv2.o
        |   |-- plat_helpers.d
        |   |-- plat_helpers.o
        |   |-- plat_log_common.d
        |   |-- plat_log_common.o
        |   |-- plat_pm.d
        |   |-- plat_pm.o
        |   |-- plat_psci_common.d
        |   |-- plat_psci_common.o
        |   |-- plat_sip_calls.d
        |   |-- plat_sip_calls.o
        |   |-- plat_sp_min_common.d
        |   |-- plat_sp_min_common.o
        |   |-- plat_topology.d
        |   |-- plat_topology.o
        |   |-- platform_common.d
        |   |-- platform_common.o
        |   |-- platform_helpers.d
        |   |-- platform_helpers.o
        |   |-- platform_mp_stack.d
        |   |-- platform_mp_stack.o
        |   |-- pmu.d
        |   |-- pmu.o
        |   |-- pmu_sram_cpus_on.d
        |   |-- pmu_sram_cpus_on.o
        |   |-- popcountdi2.d
        |   |-- popcountdi2.o
        |   |-- popcountsi2.d
        |   |-- popcountsi2.o
        |   |-- psci_common.d
        |   |-- psci_common.o
        |   |-- psci_helpers.d
        |   |-- psci_helpers.o
        |   |-- psci_main.d
        |   |-- psci_main.o
        |   |-- psci_mem_protect.d
        |   |-- psci_mem_protect.o
        |   |-- psci_off.d
        |   |-- psci_off.o
        |   |-- psci_on.d
        |   |-- psci_on.o
        |   |-- psci_setup.d
        |   |-- psci_setup.o
        |   |-- psci_suspend.d
        |   |-- psci_suspend.o
        |   |-- psci_system_off.d
        |   |-- psci_system_off.o
        |   |-- rockchip_gicv2.d
        |   |-- rockchip_gicv2.o
        |   |-- rockchip_sip_svc.d
        |   |-- rockchip_sip_svc.o
        |   |-- runtime_svc.d
        |   |-- runtime_svc.o
        |   |-- secure.d
        |   |-- secure.o
        |   |-- soc.d
        |   |-- soc.o
        |   |-- sp_min_main.d
        |   |-- sp_min_main.o
        |   |-- sp_min_plat_setup.d
        |   |-- sp_min_plat_setup.o
        |   |-- spinlock.d
        |   |-- spinlock.o
        |   |-- std_svc_setup.d
        |   |-- std_svc_setup.o
        |   |-- tf_log.d
        |   |-- tf_log.o
        |   |-- udivmoddi4.d
        |   |-- udivmoddi4.o
        |   |-- wa_cve_2017_5715_icache_inv.d
        |   |-- wa_cve_2017_5715_icache_inv.o
        |   |-- xlat_tables.d
        |   |-- xlat_tables.o
        |   |-- xlat_tables_common.d
        |   `-- xlat_tables_common.o
        |-- bl32.bin
        |-- fip.bin
        |-- lib
        |   |-- libc.a
        |   `-- libfdt.a
        |-- libc
        |   |-- abort.d
        |   |-- abort.o
        |   |-- assert.d
        |   |-- assert.o
        |   |-- exit.d
        |   |-- exit.o
        |   |-- memchr.d
        |   |-- memchr.o
        |   |-- memcmp.d
        |   |-- memcmp.o
        |   |-- memcpy.d
        |   |-- memcpy.o
        |   |-- memmove.d
        |   |-- memmove.o
        |   |-- memrchr.d
        |   |-- memrchr.o
        |   |-- memset.d
        |   |-- memset.o
        |   |-- printf.d
        |   |-- printf.o
        |   |-- putchar.d
        |   |-- putchar.o
        |   |-- puts.d
        |   |-- puts.o
        |   |-- snprintf.d
        |   |-- snprintf.o
        |   |-- strchr.d
        |   |-- strchr.o
        |   |-- strcmp.d
        |   |-- strcmp.o
        |   |-- strlcat.d
        |   |-- strlcat.o
        |   |-- strlcpy.d
        |   |-- strlcpy.o
        |   |-- strlen.d
        |   |-- strlen.o
        |   |-- strncmp.d
        |   |-- strncmp.o
        |   |-- strnlen.d
        |   |-- strnlen.o
        |   |-- strrchr.d
        |   |-- strrchr.o
        |   |-- strtok.d
        |   |-- strtok.o
        |   |-- strtol.d
        |   |-- strtol.o
        |   |-- strtoll.d
        |   |-- strtoll.o
        |   |-- strtoul.d
        |   |-- strtoul.o
        |   |-- strtoull.d
        |   `-- strtoull.o
        |-- libfdt
        |   |-- fdt.d
        |   |-- fdt.o
        |   |-- fdt_addresses.d
        |   |-- fdt_addresses.o
        |   |-- fdt_empty_tree.d
        |   |-- fdt_empty_tree.o
        |   |-- fdt_ro.d
        |   |-- fdt_ro.o
        |   |-- fdt_rw.d
        |   |-- fdt_rw.o
        |   |-- fdt_strerror.d
        |   |-- fdt_strerror.o
        |   |-- fdt_sw.d
        |   |-- fdt_sw.o
        |   |-- fdt_wip.d
        |   `-- fdt_wip.o
        |-- libwrapper
        `-- romlib

11 directories, 222 files

Save a copy somewhere safe --

user $cp -av ./build/rk3288 ../

Prepare to Build U-Boot

Note
This example will build and use peer-level directories for u-boot and rkbin, within a common project directory, to simplify relative addressing of command line parameters

Return to the project directory and get u-boot sources. The u-boot sub-directory will be created in the process:

user $cd ..
user $git clone https://source.denx.de/u-boot/u-boot.git
user $cd u-boot
user $git tag
v2023.10

Check out latest currently stable version:

user $git checkout v2023.10
Tip
Instead of cloning the complete u-boot repository as shown in the steps above, you may save some time and disc space by cloning branch v2023.10 only:
user $git clone --depth 1 --branch v2023.10 https://source.denx.de/u-boot/u-boot.git

Identify and load board-specific default configuration

user $find ./ -iname *rk3288*_defconfig | grep tinker
./configs/tinker-rk3288_defconfig
./configs/tinker-s-rk3288_defconfig

U-Boot boot-flow(s)

The Rockchip u-boot README[2] indicates that there are two possible boot-flows involving the use of either the rockchip "miniloader" or a TPL/SPL build with ATF. See much more detail at http://opensource.rock-chips.com/wiki_Boot_option In particular, note the details illustrated in the graphic at http://opensource.rock-chips.com/images/thumb/c/cd/Rockchip_bootflow20181122.jpg/894px-Rockchip_bootflow20181122.jpg Source -- http://opensource.rock-chips.com/wiki_Boot_option

Build u-boot

user $MAKEOPTS="-j$(nproc) -l$(nproc)" FEATURES=$FEATURES" -distcc -distcc-pump" PLAT=rk3288 CROSS_COMPILE=armv7a-unknown-linux-gnueabihf- make O=tinker-s-rk3288_output BL32=../rk3288/release/bl32/bl32.elf tinker-s-rk3288_defconfig all
make[1]: Entering directory '/home/joe/MyTinkerboardFiles/u-boot/tinker-s-rk3288_output'
  HOSTCC  scripts/basic/fixdep
  GEN     Makefile
  HOSTCC  scripts/kconfig/conf.o
  YACC    scripts/kconfig/zconf.tab.c
  LEX     scripts/kconfig/zconf.lex.c
  HOSTCC  scripts/kconfig/zconf.tab.o
  HOSTLD  scripts/kconfig/conf
#
# configuration written to .config
#
  GEN     Makefile
scripts/kconfig/conf  --syncconfig Kconfig
  CFG     u-boot.cfg
  GEN     include/autoconf.mk
  GEN     include/autoconf.mk.dep
  CFG     spl/u-boot.cfg
  GEN     spl/include/autoconf.mk
...
  CC      tpl/fs/fs_internal.o
  AR      tpl/fs/built-in.o
  LDS     tpl/u-boot-spl.lds
  LD      tpl/u-boot-tpl
  OBJCOPY tpl/u-boot-tpl-nodtb.bin
  COPY    tpl/u-boot-tpl.bin
  SYM     tpl/u-boot-tpl.sym
  COPY    u-boot.dtb
  MKIMAGE u-boot-dtb.img
  BINMAN  .binman_stamp
  OFCHK   .config
make[1]: Leaving directory '/home/joe/MyTinkerboardFiles/u-boot/tinker-s-rk3288_output'

Similar to the Linux kernel, menuconfig can be used to make changes to the configuration. This is optional; there is no real need to make any changes.

Tip
If the serial console employs old hardware or is "noisy," the u-boot serial console baud rate setting can be reduced. Newer systems default to 1500000 baud, but the tinker-s-rk3288_defconfig evidently sets its default at 115200. If this is still too fast, it can be changed to e.g. 9600.
user $grep -i baudrate .config
CONFIG_BAUDRATE=115200
user $make menuconfig
You probably won't need to make any other changes.

Get rkbin and create trust.img[3]

From u-boot directory, cd .. to move to the parent project directory, then get rkbin sources (peer level to the project's u-boot directory) --

user $cd rkbin/
user $./tools/trust_merger RKTRUST/RK3399TRUST.ini
out:trust.img merge success(trust.img)

Create uboot.img

If not already there, cd to /path/to/rkbin, then --

user $./tools/loaderimage --pack --uboot ../u-boot/tinker-s-rk3288_output/u-boot-dtb.bin uboot.img
load addr is 0x60000000!

pack input ../u-boot/tinker-s-rk3288_output/u-boot-dtb.bin pack file size: 553000(540 KB) crc = 0x746c261e uboot version: U-Boot 2017.09-gc64e256218-200416 #yzc (Apr 29 2020 - 16:22:05)

pack uboot.img success!

Installing u-boot

When powered on, the TinkerBoard S will attempt to find a bootloader in the following order:

  • Removable eMMC - empty connector, not populated by default on 4c Plus
  • microSD card - i.e. this is the only real option for where to put u-boot

Note that if the maskrom/eMMC Recovery jumper header is set in the "default/disable/park" position, the board will try to boot from the eMMC; if it is set in the "eMMC Recovery/MASKROM" position, it will try to boot from the SD card.

Once U-Boot is loaded on one of these devices, it can then be used to load the kernel from MMC/SD or USB external storage, or via the network. (There is no M.2 nor PCIe connector on the TinkerBoard/TInkerBoard S. By default, after exhausting other options, u-boot will connect to the local network's dhpc server, looking for tftp service from which to retrieve a bootable image (this might be considered a security concern).

Installing on microSD/eMMC

If writing to the eMMC, connect the board (microUSB) connector to a PC (USB-A).

If writing to a micro SD Card, put the card in a card reader and connect that to a PC/workstation USB port.

Note the device connected, and as root, enter the u-boot build directory, and write the images to the card.

Note
For miniloader boot option, the Rockchip community (http://opensource.rock-chips.com/wiki_Boot_option) instructs loading these files built above at the associated sectors of the eMMC/SD Card --
dd if=idbloader.img of=<device> seek=64
dd if=uboot.img of=<device> seek=16384
dd if=trust.img of=<device> seek=24576
dd if=boot.img of=<device> seek=32768
dd if=rootfs.img of=<device> seek=262144

However, it also notes that "boot.img" may also be the boot partition/folder of the rootfs, wherein the extlinux/extlinux.conf, zImage, and tinker-s-rk3288.dtb file will reside (with optional initrd and/or optional grub.efi. The example below assumes no initrd, no grub.efi, and will append the rootfs information to kernel cli, etc.

There are separate instructions at the link above for loading files pertaining to TPL/SPL boot option)
Warning
* Note that uboot.img is written starting at sector 16384, trust.img is written at sector 24576, and the scenario expects the boot.img (or the boot directory/partition) to be at sector 32768. Make sure your card is partitioned such that 32768 is the start address for the boot partition (FAT 32), and there is no other file system installed below that sector.
  • Be sure to replace /dev/sdd with the correct device!

Write output files to boot media

root #dmesg | tail ### note information about device just connected
root #cd /path/to/u-boot/
root #dd if=tinker-s-rk3288_output/idbloader.img of=/dev/sdd seek=64
140+0 records in
140+0 records out
71680 bytes (72 kB, 70 KiB) copied, 0.0350433 s, 2.0 MB/s
root #cd ../rkbin/
root #dd if=uboot.img of=/dev/sdd seek=16384
8192+0 records in
8192+0 records out
4194304 bytes (4.2 MB, 4.0 MiB) copied, 0.681352 s, 6.2 MB/s
root #dd if=trust.img of=/dev/sdd seek=24576
8192+0 records in
8192+0 records out
4194304 bytes (4.2 MB, 4.0 MiB) copied, 0.683164 s, 6.1 MB/s