Raspberry Pi 4B 64bit Image (AArch64)

1st Official Post

    Certain problems run faster in 64 bit than 32 bit (wider words, some 64-bit only registers, 64-bit only microcode speedups). have we established that LE does not swim in those waters?

    • Official Post

    Historically most of the important media drivers that LE depends upon for RPi were 32-bit only. Over time that situation has improved, but there are still missing bits. RPi4 brings more drivers. It is overall more 64-bit capable in software than previous generations but there are still gaps (mostly bits that are common with older Pi kit) and the development focus is on must-have functional items more than nice-to-have capabilities like ensuring everything can run in 64-bit (but where new code is written it should support both). For LE there is also an additional consideration for libwidevine support (needed for Netflix etc.) so even in the future when a 64-bit kernel is hopefully available we'll still be using 32-bit userspace in the same 64/32 arrangement we use on other Aarch64 devices.

    Is there a list (wiki) of the media drivers that LE depends upon so that we can see which ones are not-yet-64-bit? I'm ignorant enuf to not know what's unreasonable (i.e. picking away at porting a few from 32-bit to 64-bit). Obviously, when there's an impossibly long list, it's silly to worry about 64-bit, but someday there'll be an inflection point when it will start making sense to tilt at this windmill.

    smiles & cheers,

    steve

    • Official Post

    No wiki, only kernel sources. If/when at some future point it makes sense the Pi Foundation will switch over .. but I wouldn't expect that to be a high priority for them. Making perfect software is somewhere on the list, but helping kids learn stuff comes first, and the current assorment of 32-bit code does that job just fine.