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diff --git a/roms/u-boot/doc/README.rockchip b/roms/u-boot/doc/README.rockchip new file mode 100644 index 000000000..154166ec7 --- /dev/null +++ b/roms/u-boot/doc/README.rockchip @@ -0,0 +1,703 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (C) 2015 Google. Inc +# Written by Simon Glass <sjg@chromium.org> + +U-Boot on Rockchip +================== + +A wide range of Rockchip SoCs are supported in mainline U-Boot + +Warning +======= +This document is being moved to doc/board/rockchip, so information on it +might be incomplete or outdated. + +Prerequisites +============= + +You will need: + + - Firefly RK3288 board or something else with a supported RockChip SoC + - Power connection to 5V using the supplied micro-USB power cable + - Separate USB serial cable attached to your computer and the Firefly + (connect to the micro-USB connector below the logo) + - rkflashtool [3] + - openssl (sudo apt-get install openssl) + - Serial UART connection [4] + - Suitable ARM cross compiler, e.g.: + sudo apt-get install gcc-4.7-arm-linux-gnueabi + +Building +======== + +1. To build RK3288 board: + + CROSS_COMPILE=arm-linux-gnueabi- make O=firefly firefly-rk3288_defconfig all + + (or you can use another cross compiler if you prefer) + +2. To build RK3308 board: + - Get the rkbin + => git clone https://github.com/rockchip-linux/rkbin.git + + - Compile U-Boot + => cd /path/to/u-boot + => export BL31=/path/to/rkbin/bin/rk33/rk3308_bl31_v2.22.elf + => make roc-cc-rk3308_defconfig + => make CROSS_COMPILE=aarch64-linux-gnu- all + => ./tools/mkimage -n rk3308 -T rksd -d /path/to/rkbin/bin/rk33/rk3308_ddr_589MHz_uart2_m0_v1.26.bin idbloader.img + => cat spl/u-boot-spl.bin >> idbloader.img + +3. To build RK3399 board: + + Option 1: Package the image with Rockchip miniloader: + + - Compile U-Boot + + => cd /path/to/u-boot + => make nanopi-neo4-rk3399_defconfig + => make + + - Get the rkbin + + => git clone https://github.com/rockchip-linux/rkbin.git + + - Create trust.img + + => cd /path/to/rkbin + => ./tools/trust_merger RKTRUST/RK3399TRUST.ini + + - Create uboot.img + + => cd /path/to/rkbin + => ./tools/loaderimage --pack --uboot /path/to/u-boot/u-boot-dtb.bin uboot.img + + (Get trust.img and uboot.img) + + Option 2: Package the image with SPL: + + - Export cross compiler path for aarch64 + + - Compile ATF + + For Puma board. + + => git clone git://git.theobroma-systems.com/arm-trusted-firmware.git + => cd arm-trusted-firmware + => make CROSS_COMPILE=aarch64-linux-gnu- PLAT=rk3399 bl31 + + (export bl31.bin) + => export BL31=/path/to/arm-trusted-firmware/build/rk3399/release/bl31/bl31.bin + + For rest of rk3399 boards. + + => git clone https://github.com/ARM-software/arm-trusted-firmware.git + => cd arm-trusted-firmware + + (export cross compiler path for Cortex-M0 MCU likely arm-none-eabi-) + => make realclean + => make CROSS_COMPILE=aarch64-linux-gnu- PLAT=rk3399 + + (export bl31.elf) + => export BL31=/path/to/arm-trusted-firmware/build/rk3399/release/bl31/bl31.elf + + - Compile PMU M0 firmware + + This is optional for most of the rk3399 boards and required only for Puma board. + + => git clone git://git.theobroma-systems.com/rk3399-cortex-m0.git + => cd rk3399-cortex-m0 + + (export cross compiler path for Cortex-M0 PMU) + => make CROSS_COMPILE=arm-cortex_m0-eabi- + + (export rk3399m0.bin) + => export PMUM0=/path/to/rk3399-cortex-m0/rk3399m0.bin + + - Compile U-Boot + + => cd /path/to/u-boot + => make orangepi-rk3399_defconfig + => make + + (Get spl/u-boot-spl-dtb.bin, u-boot.itb images and some boards would get + spl/u-boot-spl.bin since it doesn't enable CONFIG_SPL_OF_CONTROL + + If TPL enabled on the target, get tpl/u-boot-tpl-dtb.bin or tpl/u-boot-tpl.bin + if CONFIG_TPL_OF_CONTROL not enabled) + +Writing to the board with USB +============================= + +For USB to work you must get your board into ROM boot mode, either by erasing +your MMC or (perhaps) holding the recovery button when you boot the board. +To erase your MMC, you can boot into Linux and type (as root) + + dd if=/dev/zero of=/dev/mmcblk0 bs=1M + +Connect your board's OTG port to your computer. + +To create a suitable image and write it to the board: + + ./firefly-rk3288/tools/mkimage -n rk3288 -T rkimage -d \ + ./firefly-rk3288/spl/u-boot-spl-dtb.bin out && \ + cat out | openssl rc4 -K 7c4e0304550509072d2c7b38170d1711 | rkflashtool l + +If all goes well you should something like: + + U-Boot SPL 2015.07-rc1-00383-ge345740-dirty (Jun 03 2015 - 10:06:49) + Card did not respond to voltage select! + spl: mmc init failed with error: -17 + ### ERROR ### Please RESET the board ### + +You will need to reset the board before each time you try. Yes, that's all +it does so far. If support for the Rockchip USB protocol or DFU were added +in SPL then we could in principle load U-Boot and boot to a prompt from USB +as several other platforms do. However it does not seem to be possible to +use the existing boot ROM code from SPL. + + +Writing to the eMMC with USB on ROC-RK3308-CC +============================================= +For USB to work you must get your board into Bootrom mode, +either by erasing the eMMC or short circuit the GND and D0 +on core board. + +Connect the board to your computer via tyepc. +=> rkdeveloptool db rk3308_loader_v1.26.117.bin +=> rkdeveloptool wl 0x40 idbloader.img +=> rkdeveloptool wl 0x4000 u-boot.itb +=> rkdeveloptool rd + +Then you will see the boot log from Debug UART at baud rate 1500000: +DDR Version V1.26 +REGFB: 0x00000032, 0x00000032 +In +589MHz +DDR3 + Col=10 Bank=8 Row=14 Size=256MB +msch:1 +Returning to boot ROM... + +U-Boot SPL 2020.01-rc1-00225-g34b681327f (Nov 14 2019 - 10:58:04 +0800) +Trying to boot from MMC1 +INFO: Preloader serial: 2 +NOTICE: BL31: v1.3(release):30f1405 +NOTICE: BL31: Built : 17:08:28, Sep 23 2019 +INFO: Lastlog: last=0x100000, realtime=0x102000, size=0x2000 +INFO: ARM GICv2 driver initialized +INFO: Using opteed sec cpu_context! +INFO: boot cpu mask: 1 +INFO: plat_rockchip_pmu_init: pd status 0xe b +INFO: BL31: Initializing runtime services +WARNING: No OPTEE provided by BL2 boot loader, Booting device without OPTEE initialization. SMC`s destined for OPTEE will rK +ERROR: Error initializing runtime service opteed_fast +INFO: BL31: Preparing for EL3 exit to normal world +INFO: Entry point address = 0x600000 +INFO: SPSR = 0x3c9 + + +U-Boot 2020.01-rc1-00225-g34b681327f (Nov 14 2019 - 10:58:47 +0800) + +Model: Firefly ROC-RK3308-CC board +DRAM: 254 MiB +MMC: dwmmc@ff480000: 0, dwmmc@ff490000: 1 +rockchip_dnl_key_pressed read adc key val failed +Net: No ethernet found. +Hit any key to stop autoboot: 0 +Card did not respond to voltage select! +switch to partitions #0, OK +mmc1(part 0) is current device +Scanning mmc 1:4... +Found /extlinux/extlinux.conf +Retrieving file: /extlinux/extlinux.conf +151 bytes read in 3 ms (48.8 KiB/s) +1: kernel-mainline +Retrieving file: /Image +14737920 bytes read in 377 ms (37.3 MiB/s) +append: earlycon=uart8250,mmio32,0xff0c0000 console=ttyS2,1500000n8 +Retrieving file: /rk3308-roc-cc.dtb +28954 bytes read in 4 ms (6.9 MiB/s) +Flattened Device Tree blob at 01f00000 +Booting using the fdt blob at 0x1f00000 +## Loading Device Tree to 000000000df3a000, end 000000000df44119 ... OK + +Starting kernel ... +[ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd042] +[ 0.000000] Linux version 5.4.0-rc1-00040-g4dc2d508fa47-dirty (andy@B150) (gcc version 6.3.1 20170404 (Linaro GCC 6.3-209 +[ 0.000000] Machine model: Firefly ROC-RK3308-CC board +[ 0.000000] earlycon: uart8250 at MMIO32 0x00000000ff0c0000 (options '') +[ 0.000000] printk: bootconsole [uart8250] enabled + +Booting from an SD card +======================= + +To write an image that boots from an SD card (assumed to be /dev/sdc): + + ./firefly-rk3288/tools/mkimage -n rk3288 -T rksd -d \ + firefly-rk3288/spl/u-boot-spl-dtb.bin out && \ + sudo dd if=out of=/dev/sdc seek=64 && \ + sudo dd if=firefly-rk3288/u-boot-dtb.img of=/dev/sdc seek=16384 + +This puts the Rockchip header and SPL image first and then places the U-Boot +image at block 16384 (i.e. 8MB from the start of the SD card). This +corresponds with this setting in U-Boot: + + #define CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR 0x4000 + +Put this SD (or micro-SD) card into your board and reset it. You should see +something like: + + U-Boot 2016.01-rc2-00309-ge5bad3b-dirty (Jan 02 2016 - 23:41:59 -0700) + + Model: Radxa Rock 2 Square + DRAM: 2 GiB + MMC: dwmmc@ff0f0000: 0, dwmmc@ff0c0000: 1 + *** Warning - bad CRC, using default environment + + In: serial + Out: vop@ff940000.vidconsole + Err: serial + Net: Net Initialization Skipped + No ethernet found. + Hit any key to stop autoboot: 0 + => + +The rockchip bootrom can load and boot an initial spl, then continue to +load a second-stage bootloader (ie. U-Boot) as soon as the control is returned +to the bootrom. Both the RK3288 and the RK3036 use this special boot sequence. +The configuration option enabling this is: + + CONFIG_SPL_ROCKCHIP_BACK_TO_BROM=y + +You can create the image via the following operations: + + ./firefly-rk3288/tools/mkimage -n rk3288 -T rksd -d \ + firefly-rk3288/spl/u-boot-spl-dtb.bin out && \ + cat firefly-rk3288/u-boot-dtb.bin >> out && \ + sudo dd if=out of=/dev/sdc seek=64 + +Or: + ./firefly-rk3288/tools/mkimage -n rk3288 -T rksd -d \ + firefly-rk3288/spl/u-boot-spl-dtb.bin:firefly-rk3288/u-boot-dtb.bin \ + out && \ + sudo dd if=out of=/dev/sdc seek=64 + +If you have an HDMI cable attached you should see a video console. + +For evb_rk3036 board: + ./evb-rk3036/tools/mkimage -n rk3036 -T rksd -d evb-rk3036/spl/u-boot-spl.bin out && \ + cat evb-rk3036/u-boot-dtb.bin >> out && \ + sudo dd if=out of=/dev/sdc seek=64 + +Or: + ./evb-rk3036/tools/mkimage -n rk3036 -T rksd -d \ + evb-rk3036/spl/u-boot-spl.bin:evb-rk3036/u-boot-dtb.bin out && \ + sudo dd if=out of=/dev/sdc seek=64 + +Note: rk3036 SDMMC and debug uart use the same iomux, so if you boot from SD, the + debug uart must be disabled + + +Booting from an SD card on RK3288 with TPL +========================================== + +Since the size of SPL can't be exceeded 0x8000 bytes in RK3288, it is not possible add +new SPL features like Falcon mode or etc. + +So introduce TPL so-that adding new features to SPL is possible because now TPL should +run minimal with code like DDR, clock etc and rest of new features in SPL. + +As of now TPL is added on Vyasa-RK3288 board. + +To write an image that boots from an SD card (assumed to be /dev/mmcblk0): + + sudo dd if=idbloader.img of=/dev/mmcblk0 seek=64 && + sudo dd if=u-boot-dtb.img of=/dev/mmcblk0 seek=16384 + +Booting from an SD card on RK3188 +================================= + +For rk3188 boards the general storage onto the card stays the same as +described above, but the image creation needs a bit more care. + +The bootrom of rk3188 expects to find a small 1kb loader which returns +control to the bootrom, after which it will load the real loader, which +can then be up to 29kb in size and does the regular ddr init. This is +handled by a single image (built as the SPL stage) that tests whether +it is handled for the first or second time via code executed from the +boot0-hook. + +Additionally the rk3188 requires everything the bootrom loads to be +rc4-encrypted. Except for the very first stage the bootrom always reads +and decodes 2kb pages, so files should be sized accordingly. + +# copy tpl, pad to 1020 bytes and append spl +tools/mkimage -n rk3188 -T rksd -d spl/u-boot-spl.bin out + +# truncate, encode and append u-boot.bin +truncate -s %2048 u-boot.bin +cat u-boot.bin | split -b 512 --filter='openssl rc4 -K 7C4E0304550509072D2C7B38170D1711' >> out + +Booting from an SD card on Pine64 Rock64 (RK3328) +================================================= + +For Rock64 rk3328 board the following three parts are required: +TPL, SPL, and the u-boot image tree blob. + + - Write TPL/SPL image at 64 sector + + => sudo dd if=idbloader.img of=/dev/mmcblk0 seek=64 + + - Write u-boot image tree blob at 16384 sector + + => sudo dd if=u-boot.itb of=/dev/mmcblk0 seek=16384 + +Booting from an SD card on RK3399 +================================= + +To write an image that boots from an SD card (assumed to be /dev/sdc): + +Option 1: Package the image with Rockchip miniloader: + + - Create idbloader.img + + => cd /path/to/u-boot + => ./tools/mkimage -n rk3399 -T rksd -d /path/to/rkbin/bin/rk33/rk3399_ddr_800MHz_v1.20.bin idbloader.img + => cat /path/to/rkbin/bin/rk33/rk3399_miniloader_v1.19.bin >> idbloader.img + + - Write idbloader.img at 64 sector + + => sudo dd if=idbloader.img of=/dev/sdc seek=64 + + - Write trust.img at 24576 + + => sudo dd if=trust.img of=/dev/sdc seek=24576 + + - Write uboot.img at 16384 sector + + => sudo dd if=uboot.img of=/dev/sdc seek=16384 + => sync + +Put this SD (or micro-SD) card into your board and reset it. You should see +something like: + +DDR Version 1.20 20190314 +In +Channel 0: DDR3, 933MHz +Bus Width=32 Col=10 Bank=8 Row=15 CS=1 Die Bus-Width=16 Size=1024MB +no stride +ch 0 ddrconfig = 0x101, ddrsize = 0x20 +pmugrf_os_reg[2] = 0x10006281, stride = 0x17 +OUT +Boot1: 2019-03-14, version: 1.19 +CPUId = 0x0 +ChipType = 0x10, 239 +mmc: ERROR: SDHCI ERR:cmd:0x102,stat:0x18000 +mmc: ERROR: Card did not respond to voltage select! +emmc reinit +mmc: ERROR: SDHCI ERR:cmd:0x102,stat:0x18000 +mmc: ERROR: Card did not respond to voltage select! +emmc reinit +mmc: ERROR: SDHCI ERR:cmd:0x102,stat:0x18000 +mmc: ERROR: Card did not respond to voltage select! +SdmmcInit=2 1 +mmc0:cmd5,20 +SdmmcInit=0 0 +BootCapSize=0 +UserCapSize=60543MB +FwPartOffset=2000 , 0 +StorageInit ok = 45266 +SecureMode = 0 +SecureInit read PBA: 0x4 +SecureInit read PBA: 0x404 +SecureInit read PBA: 0x804 +SecureInit read PBA: 0xc04 +SecureInit read PBA: 0x1004 +SecureInit read PBA: 0x1404 +SecureInit read PBA: 0x1804 +SecureInit read PBA: 0x1c04 +SecureInit ret = 0, SecureMode = 0 +atags_set_bootdev: ret:(0) +GPT 0x3380ec0 signature is wrong +recovery gpt... +GPT 0x3380ec0 signature is wrong +recovery gpt fail! +LoadTrust Addr:0x4000 +No find bl30.bin +Load uboot, ReadLba = 2000 +hdr 0000000003380880 + 0x0:0x88,0x41,0x3e,0x97,0xe6,0x61,0x54,0x23,0xe9,0x5a,0xd1,0x2b,0xdc,0x2f,0xf9,0x35, + +Load OK, addr=0x200000, size=0x9c9c0 +RunBL31 0x10000 +NOTICE: BL31: v1.3(debug):370ab80 +NOTICE: BL31: Built : 09:23:41, Mar 4 2019 +NOTICE: BL31: Rockchip release version: v1.1 +INFO: GICv3 with legacy support detected. ARM GICV3 driver initialized in EL3 +INFO: Using opteed sec cpu_context! +INFO: boot cpu mask: 0 +INFO: plat_rockchip_pmu_init(1181): pd status 3e +INFO: BL31: Initializing runtime services +INFO: BL31: Initializing BL32 +INF [0x0] TEE-CORE:init_primary_helper:337: Initializing (1.1.0-195-g8f090d20 #6 Fri Dec 7 06:11:20 UTC 2018 aarch64) + +INF [0x0] TEE-CORE:init_primary_helper:338: Release version: 1.2 + +INF [0x0] TEE-CORE:init_teecore:83: teecore inits done +INFO: BL31: Preparing for EL3 exit to normal world +INFO: Entry point address = 0x200000 +INFO: SPSR = 0x3c9 + + +U-Boot 2019.04-rc4-00136-gfd121f9641-dirty (Apr 16 2019 - 14:02:47 +0530) + +Model: FriendlyARM NanoPi NEO4 +DRAM: 1022 MiB +MMC: dwmmc@fe310000: 2, dwmmc@fe320000: 1, sdhci@fe330000: 0 +Loading Environment from MMC... *** Warning - bad CRC, using default environment + +In: serial@ff1a0000 +Out: serial@ff1a0000 +Err: serial@ff1a0000 +Model: FriendlyARM NanoPi NEO4 +Net: eth0: ethernet@fe300000 +Hit any key to stop autoboot: 0 +=> + +Option 2: Package the image with SPL: + + - Prefix rk3399 header to SPL image + + => cd /path/to/u-boot + => ./tools/mkimage -n rk3399 -T rksd -d spl/u-boot-spl-dtb.bin out + + - Write prefixed SPL at 64th sector + + => sudo dd if=out of=/dev/sdc seek=64 + + - Write U-Boot proper at 16384 sector + + => sudo dd if=u-boot.itb of=/dev/sdc seek=16384 + => sync + +Put this SD (or micro-SD) card into your board and reset it. You should see +something like: + +U-Boot SPL board init +Trying to boot from MMC1 + + +U-Boot 2019.01-00004-g14db5ee998 (Mar 11 2019 - 13:18:41 +0530) + +Model: Orange Pi RK3399 Board +DRAM: 2 GiB +MMC: dwmmc@fe310000: 2, dwmmc@fe320000: 1, sdhci@fe330000: 0 +Loading Environment from MMC... OK +In: serial@ff1a0000 +Out: serial@ff1a0000 +Err: serial@ff1a0000 +Model: Orange Pi RK3399 Board +Net: eth0: ethernet@fe300000 +Hit any key to stop autoboot: 0 +=> + +Option 3: Package the image with TPL: + + - Write tpl+spl at 64th sector + + => sudo dd if=idbloader.img of=/dev/sdc seek=64 + + - Write U-Boot proper at 16384 sector + + => sudo dd if=u-boot.itb of=/dev/sdc seek=16384 + => sync + +Put this SD (or micro-SD) card into your board and reset it. You should see +something like: + +U-Boot TPL board init +Trying to boot from BOOTROM +Returning to boot ROM... + +U-Boot SPL board init +Trying to boot from MMC1 + + +U-Boot 2019.07-rc1-00241-g5b3244767a (May 08 2019 - 10:51:06 +0530) + +Model: Orange Pi RK3399 Board +DRAM: 2 GiB +MMC: dwmmc@fe310000: 2, dwmmc@fe320000: 1, sdhci@fe330000: 0 +Loading Environment from MMC... OK +In: serial@ff1a0000 +Out: serial@ff1a0000 +Err: serial@ff1a0000 +Model: Orange Pi RK3399 Board +Net: eth0: ethernet@fe300000 +Hit any key to stop autoboot: 0 +=> + +Using fastboot on rk3288 +======================== +- Write GPT partition layout to mmc device which fastboot want to use it to +store the image + + => gpt write mmc 1 $partitions + +- Invoke fastboot command to prepare + + => fastboot 1 + +- Start fastboot request on PC + + fastboot -i 0x2207 flash loader evb-rk3288/spl/u-boot-spl-dtb.bin + +You should see something like: + + => fastboot 1 + WARNING: unknown variable: partition-type:loader + Starting download of 357796 bytes + .. + downloading of 357796 bytes finished + Flashing Raw Image + ........ wrote 357888 bytes to 'loader' + +Booting from SPI +================ + +To write an image that boots from SPI flash (e.g. for the Haier Chromebook or +Bob): + + ./chromebook_jerry/tools/mkimage -n rk3288 -T rkspi \ + -d chromebook_jerry/spl/u-boot-spl-dtb.bin spl.bin && \ + dd if=spl.bin of=spl-out.bin bs=128K conv=sync && \ + cat spl-out.bin chromebook_jerry/u-boot-dtb.img >out.bin && \ + dd if=out.bin of=out.bin.pad bs=4M conv=sync + +This converts the SPL image to the required SPI format by adding the Rockchip +header and skipping every second 2KB block. Then the U-Boot image is written at +offset 128KB and the whole image is padded to 4MB which is the SPI flash size. +The position of U-Boot is controlled with this setting in U-Boot: + + #define CONFIG_SYS_SPI_U_BOOT_OFFS 0x20000 + +If you have a Dediprog em100pro connected then you can write the image with: + + sudo em100 -s -c GD25LQ32 -d out.bin.pad -r + +When booting you should see something like: + + U-Boot SPL 2015.07-rc2-00215-g9a58220-dirty (Jun 23 2015 - 12:11:32) + + + U-Boot 2015.07-rc2-00215-g9a58220-dirty (Jun 23 2015 - 12:11:32 -0600) + + Model: Google Jerry + DRAM: 2 GiB + MMC: + Using default environment + + In: serial@ff690000 + Out: serial@ff690000 + Err: serial@ff690000 + => + +Future work +=========== + +Immediate priorities are: + +- USB host +- USB device +- Run CPU at full speed (code exists but we only see ~60 DMIPS maximum) +- NAND flash +- Boot U-Boot proper over USB OTG (at present only SPL works) + + +Development Notes +================= + +There are plenty of patches in the links below to help with this work. + +[1] https://github.com/rkchrome/uboot.git +[2] https://github.com/linux-rockchip/u-boot-rockchip.git branch u-boot-rk3288 +[3] https://github.com/linux-rockchip/rkflashtool.git +[4] http://wiki.t-firefly.com/index.php/Firefly-RK3288/Serial_debug/en + +rkimage +------- + +rkimage.c produces an SPL image suitable for sending directly to the boot ROM +over USB OTG. This is a very simple format - just the string RK32 (as 4 bytes) +followed by u-boot-spl-dtb.bin. + +The boot ROM loads image to 0xff704000 which is in the internal SRAM. The SRAM +starts at 0xff700000 and extends to 0xff718000 where we put the stack. + +rksd +---- + +rksd.c produces an image consisting of 32KB of empty space, a header and +u-boot-spl-dtb.bin. The header is defined by 'struct header0_info' although +most of the fields are unused by U-Boot. We just need to specify the +signature, a flag and the block offset and size of the SPL image. + +The header occupies a single block but we pad it out to 4 blocks. The header +is encoding using RC4 with the key 7c4e0304550509072d2c7b38170d1711. The SPL +image can be encoded too but we don't do that. + +The maximum size of u-boot-spl-dtb.bin which the boot ROM will read is 32KB, +or 0x40 blocks. This is a severe and annoying limitation. There may be a way +around this limitation, since there is plenty of SRAM, but at present the +board refuses to boot if this limit is exceeded. + +The image produced is padded up to a block boundary (512 bytes). It should be +written to the start of an SD card using dd. + +Since this image is set to load U-Boot from the SD card at block offset, +CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, dd should be used to write +u-boot-dtb.img to the SD card at that offset. See above for instructions. + +rkspi +----- + +rkspi.c produces an image consisting of a header and u-boot-spl-dtb.bin. The +resulting image is then spread out so that only the first 2KB of each 4KB +sector is used. The header is the same as with rksd and the maximum size is +also 32KB (before spreading). The image should be written to the start of +SPI flash. + +See above for instructions on how to write a SPI image. + +rkmux.py +-------- + +You can use this script to create #defines for SoC register access. See the +script for usage. + + +Device tree and driver model +---------------------------- + +Where possible driver model is used to provide a structure to the +functionality. Device tree is used for configuration. However these have an +overhead and in SPL with a 32KB size limit some shortcuts have been taken. +In general all Rockchip drivers should use these features, with SPL-specific +modifications where required. + +GPT partition layout +---------------------------- + +Rockchip use a unified GPT partition layout in open source support. +With this GPT partition layout, uboot can be compatilbe with other components, +like miniloader, trusted-os, arm-trust-firmware. + +There are some documents about partitions in the links below. +http://rockchip.wikidot.com/partitions + +-- +Jagan Teki <jagan@amarulasolutions.com> +27 Mar 2019 +Simon Glass <sjg@chromium.org> +24 June 2015 |