Development board cannot be mounted, uboot has a lot of JFFS2: alert information

References and materials:
“Uboot sf command usage” kickxxx
When running the development board, it prompts the following alarm:

cp: can't stat '/progs/rec/*': No such file or directory
/dev/mtdblock5
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000010: 0xdde4 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000014: 0x9a31 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000018: 0x2648 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x0000001c: 0xb317 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000020: 0xe2ae instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000024: 0x36f7 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000028: 0xe9f5 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x0000002c: 0xecb9 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000030: 0xc0b5 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000034: 0x5339 instead
jffs2: Further such events for this erase block will not be printed
………… ………… …………
………… ………… …………
………… ………… …………
jffs2: Empty flash at 0x00072000 ends at 0x00072010
jffs2: Empty flash at 0x00074000 ends at 0x00074004
jffs2: Empty flash at 0x00074008 ends at 0x00074010
jffs2: Empty flash at 0x00076000 ends at 0x00076010
jffs2: Empty flash at 0x00078000 ends at 0x0007800c
jffs2: Empty flash at 0x0007a000 ends at 0x0007a010
jffs2: Empty flash at 0x0007c000 ends at 0x0007c010
jffs2: Empty flash at 0x0007e000 ends at 0x0007e010
jffs2: Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes
jffs2: empty_blocks 0, bad_blocks 0, c->nr_blocks 8
mount: mounting /dev/mtdblock5 on /etc/conf.d/ failed: Input/output error
/home/bashrc.sh: line 38: can't create /proc/sys/vm/extra_free_kbytes: nonexistent directory

probe 0x0;
SF probe 0x0; sf erase 0x780000 0x800000


SF read erase
read erase
SF read erase
SF read erase
SF read>se
SF read erase>r> SF write erase
SF read erase
SF read erase
SF read erase
SF read erase
SF write

command

explain

use example

meaning

sf, the probe [[bus:] cs] [hz] [mode]

init flash device on given SPI bus and chip Select

sf, read addr offset len

read 'len bytes starting at "offset" to the memory at "addr"

sf, read 0x82000000 0x10000 0x20000 ash offset 0x10000(64KB), length 0x20000(128KB), 0x82000000 Offset and length minimum unit operation is Byte

sf, write addr offset len

write 'len bytes from memor at' addr to flash at "offset"

0 x82000000 sf, write 0x0 0x200008200 0000 bytes, 0x0 bytes, 0x20000 bytes, 0x0 bytes, 0x0 bytes, 0x0 bytes, 0x0 bytes Offset and length minimum unit operation is Byte

sf, erase offset [+] len

erase 'len bytes from' offset '+' len 'round up' len 'to block size

sf, erase 0 x0 0x10000 ase block at offset 0x0 to 0x10000 Erase block at offset 0x0 Offset and len parameters must be erase block aligned

sf, update addr offset len

erase and write 'len bytes from the memory at "addr" to flash the at "Offset"


From the SF command, we can see several points:

Support Byte level read and write operation, support random access.
How to verify the effect of reading and writing
command can combine uboot md, sf, read, sf, write involves memory operations, can use the md for memory data
md x82000000 0 0 x100
0 x82000000 printing, 256 bytes of memory length range data

If the reference quotes your creation, and the reference, data does not sign your name, please do contact me to add, bring trouble to you!

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