u-boot/configs/a7y17lte_defconfig
Dzmitry Sankouski d5c4ec4aa3 board: axy17lte: get board usable - add bootcmd and docs
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:
- Rearrange defconfig option order
- Add CONFIG_SAVE_PREV_BL_* options
- Doc updates:
  - remove wrong SBOOT memory corruption note, because
  memory is changed during u-boot bringup process,
  not by SBOOT
  - put payload on ramdisk place in abl boot image
  creation step

Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
2022-04-04 19:02:03 -04:00

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CONFIG_ARM=y
CONFIG_SYS_CONFIG_NAME="exynos78x0-common"
CONFIG_SKIP_LOWLEVEL_INIT=y
CONFIG_ARCH_EXYNOS=y
CONFIG_SYS_TEXT_BASE=0x40001000
CONFIG_ARCH_EXYNOS7=y
CONFIG_TARGET_A7Y17LTE=y
CONFIG_NR_DRAM_BANKS=12
CONFIG_DEFAULT_DEVICE_TREE="exynos78x0-axy17lte"
CONFIG_SYS_LOAD_ADDR=0x40001000
CONFIG_FIT=y
CONFIG_USE_PREBOOT=y
CONFIG_PREBOOT="echo Read pressed buttons status;KEY_VOLUMEUP=gpa20;KEY_HOME=gpa17;KEY_VOLUMEDOWN=gpa21;KEY_POWER=gpa00;PRESSED=0;RELEASED=1;if gpio input $KEY_VOLUMEUP; then setenv VOLUME_UP $PRESSED; else setenv VOLUME_UP $RELEASED; fi;if gpio input $KEY_VOLUMEDOWN; then setenv VOLUME_DOWN $PRESSED; else setenv VOLUME_DOWN $RELEASED; fi;if gpio input $KEY_HOME; then setenv HOME $PRESSED; else setenv HOME $RELEASED; fi;if gpio input $KEY_POWER; then setenv POWER $PRESSED; else setenv POWER $RELEASED; fi;"
CONFIG_SAVE_PREV_BL_FDT_ADDR=y
CONFIG_SAVE_PREV_BL_INITRAMFS_START_ADDR=y
# CONFIG_DISPLAY_CPUINFO is not set
CONFIG_HUSH_PARSER=y
CONFIG_CMD_GPIO=y
CONFIG_CMD_I2C=y
CONFIG_DM_I2C_GPIO=y
CONFIG_LMB_MAX_REGIONS=64