U-boot is intended to replace linux kernel in android boot image(ABL), and it's FIT payload to replace initramfs file. The boot process is similar to boot image with linux: - android bootloader (ABL) unpacks android boot image - ABL sets `linux,initrd-start property` in chosen node in unpacked FDT - ABL sets x0 register to FDT address, and passes control to u-boot - u-boot reads x0 register, and stores it in `prevbl_fdt_addr` env variable - u-boot reads `linux,initrd-start` property, and stores it in `prevbl_initrd_start_addr`
In this way, u-boot bootcmd relies on `prevbl_initrd_start_addr` env variable, and boils down to `bootm $prevbl_initrd_start_addr`. If more control on boot process is desired, pack a boot script in FIT image, and put it to default configuration
What done: - strip unneeded config options - add FIT image support - increase LMB_MAX_REGIONS, to store all linux dtb reserved memory regions - add linux kernel image header
Uart driver causes hang, when u-boot is used in android boot image instead of linux. Temporary disable console driver, until investigated and fixed.
Signed-off-by: Dzmitry Sankouski dsankouski@gmail.com Cc: Ramon Fried rfried.dev@gmail.com --- Changes for v2: - change signed off line - add CONFIG_SAVE_PREV_BL_FDT_ADDR. It's needed to boot android stock kernel - change bootcmd to source bootscript from FIT image for more flexibility
configs/starqltechn_defconfig | 13 +++++++--- doc/board/qualcomm/sdm845.rst | 47 ++++++++++++++++++++++++++++++++++- include/configs/sdm845.h | 5 ++++ 3 files changed, 60 insertions(+), 5 deletions(-)
diff --git a/configs/starqltechn_defconfig b/configs/starqltechn_defconfig index f57bb859cc..40d336dc9f 100644 --- a/configs/starqltechn_defconfig +++ b/configs/starqltechn_defconfig @@ -2,13 +2,14 @@ CONFIG_ARM=y CONFIG_SKIP_LOWLEVEL_INIT=y CONFIG_POSITION_INDEPENDENT=y CONFIG_ARCH_SNAPDRAGON=y -CONFIG_SYS_TEXT_BASE=0x80000000 -CONFIG_SYS_MALLOC_LEN=0x81f000 CONFIG_DEFAULT_DEVICE_TREE="starqltechn" +CONFIG_BOOTDELAY=0 +CONFIG_FIT=y +CONFIG_FIT_VERBOSE=y CONFIG_TARGET_STARQLTECHN=y CONFIG_IDENT_STRING="\nSamsung S9 SM-G9600" CONFIG_SYS_LOAD_ADDR=0x80000000 -CONFIG_USE_PREBOOT=y +CONFIG_LMB_MAX_REGIONS=64 # CONFIG_DISPLAY_CPUINFO is not set CONFIG_HUSH_PARSER=y CONFIG_CMD_GPIO=y @@ -20,5 +21,9 @@ CONFIG_PM8916_GPIO=y CONFIG_PINCTRL=y CONFIG_DM_PMIC=y CONFIG_PMIC_PM8916=y -CONFIG_MSM_GENI_SERIAL=y +CONFIG_REQUIRE_SERIAL_CONSOLE=n +CONFIG_MSM_GENI_SERIAL=n CONFIG_SPMI_MSM=y +CONFIG_LINUX_KERNEL_IMAGE_HEADER=y +CONFIG_SAVE_PREV_BL_INITRAMFS_START_ADDR=y +CONFIG_SAVE_PREV_BL_FDT_ADDR=y diff --git a/doc/board/qualcomm/sdm845.rst b/doc/board/qualcomm/sdm845.rst index cd46cbe9cf..b00a30a313 100644 --- a/doc/board/qualcomm/sdm845.rst +++ b/doc/board/qualcomm/sdm845.rst @@ -17,7 +17,9 @@ It is loaded as an Android boot image through ABL
Installation ------------ -First, setup ``CROSS_COMPILE`` for aarch64. Then, build U-Boot for your board:: +Build +^^^^^^^^^^^^^^^^^^^^^^^^ +Setup ``CROSS_COMPILE`` for aarch64 and build U-Boot for your board::
$ export CROSS_COMPILE=<aarch64 toolchain prefix> $ make <your board name here, see Boards section>_defconfig @@ -25,6 +27,49 @@ First, setup ``CROSS_COMPILE`` for aarch64. Then, build U-Boot for your board::
This will build ``u-boot.bin`` in the configured output directory.
+Generate FIT image +^^^^^^^^^^^^^^^^^^^^^^^^ +See doc/uImage.FIT for more details + +Pack android boot image +^^^^^^^^^^^^^^^^^^^^^^^^ +We'll assemble android boot image with ``u-boot.bin`` instead of linux kernel, +and FIT image instead of ``initramfs``. Android bootloader expect gzipped kernel +with appended dtb, so let's mimic linux to satisfy stock bootloader: + +- create dump dtb:: + + workdir=/tmp/prepare_payload + mkdir -p "$workdir" + cd "$workdir" + mock_dtb="$workdir"/payload_mock.dtb + + dtc -I dts -O dtb -o "$mock_dtb" << EOF + /dts-v1/; + / { + memory { + /* We expect the bootloader to fill in the size */ + reg = <0 0 0 0>; + }; + + chosen { }; + }; + EOF + +- gzip u-boot ``gzip u-boot.bin`` +- append dtb to gzipped u-boot: ``cat u-boot.bin.gz "$mock_dtb" > u-boot.bin.gz-dtb`` + +Now we've got everything to build android boot image::: + + mkbootimg --base 0x0 --kernel_offset 0x00008000 \ + --ramdisk_offset 0x02000000 --tags_offset 0x01e00000 \ + --pagesize 4096 --second_offset 0x00f00000 \ + --ramdisk "$fit_image" \ + --kernel u-boot.bin.gz-dtb \ + -o boot.img + +Flash image with your phone's flashing method. + Boards ------------ starqlte diff --git a/include/configs/sdm845.h b/include/configs/sdm845.h index af9ba197d4..df90c04af3 100644 --- a/include/configs/sdm845.h +++ b/include/configs/sdm845.h @@ -16,6 +16,11 @@ /* Generic Timer Definitions */ #define COUNTER_FREQUENCY 19000000
+#define CONFIG_EXTRA_ENV_SETTINGS \ + "bootm_size=0x4000000\0" \ + "bootcmd=source $prevbl_initrd_start_addr:bootscript\0" \ + "bootm_low=0x80000000\0" + /* Size of malloc() pool */ #define CONFIG_SYS_BOOTM_LEN SZ_64M