Use ROM memcpy and friends over compiler-builtins function

[MabezDev]

nm examples/target/xtensa-esp32s3-none-elf/release/gpio_interrupt | grep memcpy shows 0x400011f4 on esp32s3, so it looks like this is correctly overriding the linkage.

@bjoernQ maybe you were using PROVIDE which I think only "fills" in the symbol if its missing.

I think the last time memcpy from ROM was enabled, bad things with esp-wifi happened, @bjoernQ do you recall this, and would you mind testing?

[bjoernQ]

@bjoernQ maybe you were using PROVIDE which I think only "fills" in the symbol if its missing.

I thought I was overriding the symbol, not providing but I see the changed symbol here. Whatever 🤷‍♂️

I think the last time memcpy from ROM was enabled, bad things with esp-wifi happened, @bjoernQ do you recall this, and would you mind testing?

I think there was something the other way around. For some chips esp-wifi already uses the ROM functions and some crypto (?) driver example in esp-hal broke 🤔 But can't find the issue - not in esp-wifi and not in esp-hal issues

[bjoernQ]

Found the issue: https://github.com/esp-rs/esp-wifi/issues/245

Hopefully just the driver makes assumptions which we can fix - or maybe it's just working now

[bjoernQ]

So ... everything works except ESP32-S2 BUT it also doesn't work with esp-hal 0.16.0

It worked with esp-hal 6a663f8 however 😲

Oh I see: 0240e2b breaks it

[jessebraham]

cc @playfulFence

[bjoernQ]

Just double checked: I can make esp-wifi work with this by locally commenting out crate::soc::trng::ensure_randomness();

So, it's definitely not a problem of this PR

[bjoernQ]

Just double checked: I can make esp-wifi work with this by locally commenting out crate::soc::trng::ensure_randomness();

So it's definitely not a problem of this PR

[playfulFence]

I will investigate this problem

[bjoernQ]

LGTM

[jessebraham]

LGTM, hopefully the TRNG issues will be resolved tomorrow morning!