Re: arm64 mrs and system registers

From: Kyle Evans <kevans_at_FreeBSD.org>
Date: Tue, 09 Apr 2024 07:04:14 UTC
On 4/8/24 14:02, Paul Floyd wrote:
 > Hi
 >
 > I've been looking at this bugzilla item
 >
 > https://bugs.kde.org/show_bug.cgi?id=392146
 >
 > Is there any difference between Linux and FreeBSD when it comes to what
 > registers and fields are exposed by the kernel (see comment 17 in the
 > link above).
 >
 > I did have a poke around the kernel code but it's a bit hard to tell
 > exactly which of the access macros are being used, without exhaustively
 > grepping for them one by one.
 >
 > A+
 > Paul
 >

mrs emulation is handled as an undefined instruction, so the exhaustive 
list of what we actually emulate should pretty much be:

https://cgit.freebsd.org/src/tree/sys/arm64/arm64/undefined.c#n96

Thanks,

Kyle Evans