我正在使用 yocto 为 raspberrypi3 构建汽车级 linux 演示映像。我正在为 OTA 功能添加一个层 agl-sota。这是我的u-boot中断的地方。根据 defconfig CONFIG_ENV_EXT4_DEVICE_AND_PART="0:1" 启动时，u-boot 采用 mmc0，这是可以通过 'mmc info' 和分区 1 验证的 sd 卡。但它显示：
U-Boot 2020.10 (Jun 29 2020 - 03:06:40 +0000)
DRAM: 768 MiB
RPI 3 Model B (0xa02082)
MMC: mmc@7e202000: 0, sdhci@7e300000: 1
Loading Environment from FAT... *** Warning - bad CRC, using default environment
In: serial
Out: vidconsole
Err: vidconsole
Net: No ethernet found.
starting USB...
Bus usb@7e980000: USB DWC2
scanning bus usb@7e980000 for devices... 3 USB Device(s) found
scanning usb for storage devices... 0 Storage Device(s) found
Hit any key to stop autoboot: 0
switch to partitions #0, OK
mmc0 is current device
Scanning mmc 0:1...
Card did not respond to voltage select!
Device 0: unknown device
Waiting for Ethernet connection... unable to connect.
...
...
u-boot >
'mmc 信息' 输出：
U-Boot> mmc info
Device: mmc@7e202000
Manufacturer ID: 3
OEM: 5344
Name: SU16G
Bus Speed: 50000000
Mode: SD High Speed (50MHz)
Rd Block Len: 512
SD version 3.0
High Capacity: Yes
Capacity: 14.8 GiB
Bus Width: 4-bit
Erase Group Size: 512 Bytes
什么配置问题不允许 u-boot 引导内核。？我正在使用 raspberrypi 成像器来闪烁 wic.xz 图像。