SD Card Root File System expected data

U-Boot SPL 2020.10 (Jun 10 2021 - 23:15:43 -0600)
Reset state: Cold
MPU         1200000 kHz
L3 main     400000 kHz
Main VCO    2400000 kHz
Per VCO     2000000 kHz
EOSC1       25000 kHz
HPS MMC     50000 kHz
UART        100000 kHz
DDR: 4096 MiB
SDRAM-ECC: Initialized success with 931 ms
QSPI: Reference clock at 400000 kHz
WDT:   Started with servicing (30s timeout)
Trying to boot from SPI


U-Boot 2020.10 (Jun 10 2021 - 23:20:04 -0600)socfpga_stratix10

CPU:   Intel FPGA SoCFPGA Platform (ARMv8 64bit Cortex-A53)
Model: SoCFPGA Stratix 10 SoCDK
DRAM:  4 GiB
WDT:   Started with servicing (30s timeout)
MMC:   dwmmc0@ff808000: 0
Loading Environment from SPIFlash... SF: Detected mt25qu02g with page size 256 B                            l 256 MiB
OK
In:    serial0@ffc02000
Out:   serial0@ffc02000
Err:   serial0@ffc02000
# mmc info
Device: dwmmc0@ff808000
Manufacturer ID: 27
OEM: 5048
Name: SD16G
Bus Speed: 50000000
Mode: SD High Speed (50MHz)
Rd Block Len: 512
SD version 3.0
High Capacity: Yes
Capacity: 14.4 GiB
Bus Width: 4-bit
Erase Group Size: 512 Bytes
# tftpb 0x10000000 emmc.img
done
Bytes transferred = 402653184 (18000000 hex)
# mmc write 0x10000000 0x000000 0xC0000
MMC write: dev # 0, block # 0, count 786432 ... 786432 blocks written: OK
# mmc read 0x04000000 0x800 0x100
MMC read: dev # 0, block # 2048, count 256 ... 256 blocks read: OK
# md.b 0x04000000 0x100
04000000: eb 3c 90 6d 6b 66 73 2e 66 61 74 00 02 04 04 00    .<.mkfs.fat.....
04000010: 02 00 02 00 00 f8 00 01 20 00 40 00 00 00 00 00    ........ .@.....
04000020: 00 00 04 00 80 00 29 db b7 00 d5 4e 4f 20 4e 41    ......)....NO NA
04000030: 4d 45 20 20 20 20 46 41 54 31 36 20 20 20 0e 1f    ME    FAT16   ..
04000040: be 5b 7c ac 22 c0 74 0b 56 b4 0e bb 07 00 cd 10    .[|.".t.V.......
04000050: 5e eb f0 32 e4 cd 16 cd 19 eb fe 54 68 69 73 20    ^..2.......This
04000060: 69 73 20 6e 6f 74 20 61 20 62 6f 6f 74 61 62 6c    is not a bootabl
04000070: 65 20 64 69 73 6b 2e 20 20 50 6c 65 61 73 65 20    e disk.  Please
04000080: 69 6e 73 65 72 74 20 61 20 62 6f 6f 74 61 62 6c    insert a bootabl
04000090: 65 20 66 6c 6f 70 70 79 20 61 6e 64 0d 0a 70 72    e floppy and..pr
040000a0: 65 73 73 20 61 6e 79 20 6b 65 79 20 74 6f 20 74    ess any key to t
040000b0: 72 79 20 61 67 61 69 6e 20 2e 2e 2e 20 0d 0a 00    ry again ... ...
040000c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
040000d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
040000e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................
040000f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................