Check if bootm start succeeded before trying to loados

[penguinwhisperer]

When using a U-boot FIP with CONFIG_FIT_SIGNATURE=y, attempting to boot an Image.itb signed with a different key on the LAN969x will cause the device to bootloop and requires manually fixing in U-boot. This is due to no checks being done when ramboot finishes running bootm start, resulting in bootm loados trying to load an invalid image and U-boot panicking.

If ramboot is called from mmc_tryboot (which is the default path from bootcmd), mmc_swap will run at the end of the early finished mmc_tryboot situation to swap to the alternate, working Image.itb file on the other partition. Tested with lan969x_ev23x71a, other dual-image MMC devices may also be able to apply this patch.

U-Boot 2024.04 (Mar 23 2026 - 10:24:31 +0000)

CPU:   ARM A53
Model: lan969x ev23x71a (pcb8398)
DRAM:  896 MiB (effective 897.9 MiB)
Core:  32 devices, 17 uclasses, devicetree: fit
MMC:   emmc@e0830000: 0
Loading Environment from MMC... OK
In:    serial
Out:   serial
Err:   serial
Net:   eth0: switch@0
Hit any key to stop autoboot:  0  
7434999 bytes read in 177 ms (40.1 MiB/s)
Working FDT set to 64000000
libfdt fdt_path_offset() returned FDT_ERR_NOTFOUND
libfdt fdt_path_offset() returned FDT_ERR_NOTFOUND
## Loading kernel from FIT Image at 64000000 ...
  Using 'lan9698_ev23x71a_0_at_lan969x' configuration
  Verifying Hash Integrity ... sha1,rsa2048:dev-  error!
Verification failed for '<NULL>' hash node in 'lan9698_ev23x71a_0_at_lan969x' config node
Failed to verify required signature 'key-dev'
Bad Data Hash
ERROR -2: can't get kernel image!
  XIP Invalid Image to 0
"Synchronous Abort" handler, esr 0x96000147, far 0x0
elr: 0000000000001980 lr : 0000000000004050 (reloc)
elr: 0000000097f3f980 lr : 0000000097f42050
x0 : 0000000000000000 x1 : 0000000000000000
x2 : 0000000000000040 x3 : 000000000000003f
x4 : 0000000000000000 x5 : 0000000097b2ac7c
x6 : 0000000000000030 x7 : 0000000097b2b120
x8 : 0000000000000010 x9 : 00000000ffffffd0
x10: 000000000000000d x11: 0000000000000006
x12: 0000000097b2b04c x13: 0000000064000000
x14: 00000000ffffffff x15: 0000000097b2ac7c
x16: 0000000097f4c144 x17: 71691b435758f5f2
x18: 0000000097b2dd90 x19: 0000000000000000
x20: 0000000097fda9d8 x21: 0000000000000008
x22: 0000000000000000 x23: 0000000097b2b270
x24: 0000000000000000 x25: 0000000000000000
x26: 0000000000000000 x27: 0000000000000000
x28: 0000000000000000 x29: 0000000097b2b1a0
 
Code: d2800082 9ac32042 d1000443 8a230000 (d50b7e20)  
Resetting CPU ...