Add kASLR for rk3399 u-boot

[Manouchehri]

WIP

[Manouchehri]

Could someone with UART run kaslrseed in u-boot to see why it's failing?

Maybe @paolosabatino if you have one? =)

[paolosabatino]

Could someone with UART run kaslrseed in u-boot to see why it's failing?

Maybe @paolosabatino if you have one? =)

I have the equipment, but unfortunately me and the equipment will be very far in the next week and can't give immediate support 😮‍💨

[Manouchehri]

I have a serial console working now. It looks like u-boot still can't find the RNG, even with this patch. Trying to figure out where my mistake is..

[Manouchehri]

For anyone reading this, my mistake was having the clocks manually defined in u-boot. Getting rid of those seems to have got it working.

[Tonymac32]

@igorpecovnik this commit is only adding the feature to the R4S u-boot config, but attempting to use it for all boards via the shared bootscript. I've been asked what the extra boot noise is "unknown command 'kaslrseed' - try 'help'

[Manouchehri]

@Tonymac32 The correct fix is to add kASLR to those other boards. IMO the warning is a good warning, as no kASLR is not a good thing.

[Tonymac32]

No disagreement from me, however upon review this should heave been requested before merge. Do you know the status of this feature on RK3328, RK3588, RK3568, etc?

[Manouchehri]

It was mentioned in #4306 (comment).

Ideally, this should be eventually addressed upstream in u-boot for all devices with a hardware RNG. The main motivation here is that I have some of these RK3399 devices, and was willing to test/maintain the patch.

I don't know the status of this feature on other boards, that would require users to tell us which chipset they're using when they see the warning message. (e.g. I still don't know what device you're using, other than it's probably not a R4S.)