Boot to FEL by holding home button and pressing power button 4 times.

[     0.271]HELLO ;) BOOT0 is starting!
[     0.281]AXP22 Voff=3.3V
[     0.284]fel flag  = 0x00000000
[     0.293]DRAM: 512
[     0.312]MMC3 v5.1 HSDDR52/DDR50 8 bit 7456 MB
[     0.362]Entry_name        = u-boot
[     0.370]Entry_name        = soc-cfg
[     0.374]Entry_name        = dtb
[     0.378]Jump to u-boot


U-Boot 2014.07-hg78e7bb6939f0 (Aug 08 2023 - 15:56:03) Allwinner Technology , Build: 78e7bb6939f0

normal mode
i2c_init: by cpux
[      0.398]pmbus:   ready
[      0.413]PMU: AXP221
[      0.413]PMU: AXP22X found
[      0.414]PMU: dcdc2 1260
[      0.416]IC Version: 1(0:A 1:B 2:other)
[      0.419]PMU: pll1 1008 Mhz,PLL6=600 Mhz
AXI=336 Mhz,AHB=100 Mhz, APB1=50 Mhz
dcdc1_vol = 3000, onoff=1
dcdc2_vol = 1260, onoff=1
dcdc3_vol = 1800, onoff=0
dcdc4_vol = 1100, onoff=1
dcdc5_vol = 1350, onoff=1
aldo1_vol = 3000, onoff=0
aldo2_vol = 1800, onoff=1
aldo3_vol = 3000, onoff=1
dldo1_vol = 1800, onoff=1
dldo2_vol = 3300, onoff=0
dc1sw_vol = 3300, onoff=0
dc5ldo_vol = 1100, onoff=0
DRAM:  512 MiB
fdt addr: 0x56ddc0f8
gd->fdt_size: 0x11ec0
Relocation Offset is: 15f3b000
gic: normal mode
[      0.535]MMC:        3
[mmc]: mmc driver ver 2016-08-01 13:45:00
[mmc]: get sdc_ex_dly_used 2, use auto tuning sdly
[mmc]: card3 io is 1.8V.
[mmc]: get sdc3 sdc_tm4_hs200_max_freq 100.
[mmc]: get sdc3 sdc_tm4_hs400_max_freq 100.
SUNXI SD/MMC: 3
[mmc]: 50 MHz...
[mmc]: sample: 51 - 196(ps)
[mmc]: ds: 52 - 192(ps)
[mmc]: 100 MHz...
[mmc]: sample: 26 - 192(ps)
[mmc]: ds: 25 - 200(ps)
[mmc]: media type 0x8000000
[mmc]: host caps: 0x1ef
[mmc]: MMC3: v5.1 HSSDR52/SDR25 50MHz 8 bit 7456 MB
[mmc]: already at HSSDR52_SDR25 mode
[mmc]: EOL Info(Rev blks): Normal
[mmc]: Wear out(type A): 0%-10% life time used
[mmc]: Wear out(type B): 0%-10% life time used
[      0.611]sunxi flash init ok
Using default environment

bootcmd set setargs_mmc
vbus pc exist, limit to pc
pre sys mode
Bus:2 VBat:4225 Ratio:100
Disable PF0-PF5
SW fel:   1
VBUS req: 0
KEYCOUNTER:1
KEYCOUNTER:2
Entering FEL
set next system status
sunxi_board_close_source
[mmc]: MMC Device 2 not found
[mmc]: mmc 2 not find, so not exit
[mmc]: mmc exit start
[mmc]: 50 MHz...
[mmc]: sample: 52 - 192(ps)
[mmc]: ds: 50 - 200(ps)
[mmc]: 100 MHz...
[mmc]: sample: 25 - 200(ps)
[mmc]: ds: 26 - 192(ps)
[mmc]: mmc 3 exit ok
reset cpu
[     0.271]HELLO ;) BOOT0 is starting!
[     0.280]AXP22 Voff=3.3V
[     0.283]fel flag  = 0x5aa5a55a
[     0.286]eraly jump fel