[yocto] mips64 with 'seh' instruction?

[Khem Raj]

On 1/26/17 2:26 AM, Jason Cooper wrote:
> Folks,
> 
> I'm trying to build a mips64 toolchain and qemu runtime. I can build and
> run code but if I link with a third-party library that contains the
> 'seh' assembly instruction the executable is killed with SIGILL Illegal
> Instruction, when run with qemu.
> 
> If I run the program on the target it works fine. Looking at the
> disassembly shows me that this is when qemu is trying to execute the
> 'seh' instruction. This is Krogoth 2.1.2 with:
> 
> MACHINE = "qemumips64"
> TARGET_FPU = "soft"
> DEFAULTTUNE = "mips64-nf"
> TUNE_FEATURES = "n64 bigendian"
> 
> The 'seh' instruction was introduced in mips32 Release 2, I believe. I
> tried a DEFAULTTUNE of "mips32r2" and a few others but they did not
> help... or perhaps I should be looking at the qemu code?

Right. qemu supports seh/seb for long time for mips32r2, so I believe
first you should see if we are invoking qemu with right machine type
which is based on mips32r2 architecture. A quick look into runqemu code
shows that we are using -machine malta which may be mips32r1 emulation

> 
> Thanks
> 
> Jason
> 
> 
>