Fallback kernel
Quoted 7 lines · Wolfgang Denk
Quoted 6 lines
I'm using two Linux kernel a fallback (safe) kernel and a kernel downloaded in flash via ethernet. I'd like that u-boot starts the downloaded kernel, if this kernel fails for more than N times uboot starts the fallback. Is there already something like in uboot or how can I do that?
Quoted 8 lines
U-Boot supports the "bootcount" variable to implement the Boot Count Limit feature (see CGL Requirements Definition). However, this requires a little processor specific support which so far is available only on few CPUs (but trivial to add where missing).
Best regards,
Wolfgang Denk
Why does it require a little processor specific support? In the bootcount_load and bootcount_store, we could use an uboot environment variable to store and load the value (if the env is in flash for example), isn't it?
Hi Marco,
Quoted 4 lines
Why does it require a little processor specific support? In the
bootcount_loadandbootcount_store, we could use an uboot environment variable to store and load the value (if the env is in flash for example), isn't it?
Because we do not want to erase a flash sector for every boot iteration.
Ok, this could be implemented in a more clever way, but this effort is better spent on other areas of U-Boot when most CPUs offer some kind of a "breadcrumb" register surviving resets.
Cheers
Detlev
Signature · 5 lines
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