Does your application work if you don't use your custom trap handler? In the 
old days, RTEMS used lazy FPU context switching so FPU disabled traps could 
happen and were handled by the kernel. Also note that if you use FPU 
instructions in the Init task, you need a special FPU attribute for it ...

Jiri.

On 12/3/19 3:48 PM, Schweikhardt, Jens (TSPCE3-TL4) wrote:
>
> Hello, world\n
>
>  
>
> I have a question about the use of trap 4 by RTEMS on Sparc32 (leon3).
>
> Since our app needs FP, we set the PSR[EF] bit during the boot process before 
> RTEMS is invoked.
>
> Since we don’t expect the fp_disabled trap (4) to occur, we install a fatal 
> handler for it with
>
> rtems_interrupt_catch(&fatalTrapHandler, 4, &old);
>
>  
>
> However, the fatalTrapHandler is invoked a short time after application start 
> (we use the Init() task
>
> and start a handful of additional tasks, all of which have attribute 
> RTEMS_FLOATING_POINT)
>
> and the PSR[EF] bit is indeed cleared. None of our tasks
>
> clears that bit, so we suspect RTEMS does it for some reason.
>
>  
>
> Question: is an RTEMS/sparc application allowed to install a handler for trap 
> 4? I could not find an
>
> answer in the docs for SPARC Specific Information.
>
>  
>
> Thanks for any insight!
> Regards, Jens
>
>  
>
>
> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Tesat-Spacecom GmbH & Co. KG
> Sitz: Backnang; Registergericht: Amtsgericht Stuttgart HRA 270977
> Persoenlich haftender Gesellschafter: Tesat-Spacecom Geschaeftsfuehrungs GmbH;
> Sitz: Backnang; Registergericht: Amtsgericht Stuttgart HRB 271658;
> Geschaeftsfuehrung: Dr. Marc Steckling, Kerstin Basche, Ralf Zimmermann
>
> banner
>
> _______________________________________________
> users mailing list
> users@rtems.org
> http://lists.rtems.org/mailman/listinfo/users
_______________________________________________
users mailing list
users@rtems.org
http://lists.rtems.org/mailman/listinfo/users

Reply via email to