Re: RTEMS soft reboot

[Kate Feng <feng1@bnl.gov>]

Till Straumann wrote:
> Matt Rippa wrote:
> > Running 'exit' on an RTEMS ioc I get a stack trace. Is exit the 
> > intended mechanism for a soft reboot?
> Well - 'exit' should bring you back to the point where you
> started RTEMS. However, this is not really possible on all
> boards because the environment that booted RTEMS may
> have been destroyed (in your case, RTEMS overwrites
> critical memory that was used by PPCBug) and in this case
> a hard reset may be required (IIRC, 'exit' should in these
> cases do that for you so you may have encountered a bug).
>
> Different BSPs used to have their own API to reset the board
> (PPC/shared boards used to call this rtemsReboot(), IIRC)
> but, again IIRC, this should have been made more consistent
> (don't recall if this happened before or after forking 4.9) and
> renamed 'bsp_reset()' across multiple architectures/boards.
>
> Now that I write all this I believe I remember that the old
> motorola BSP (mvme2300..2700) indeed has a bug; it tries
> to reset via the KBD controller and (again IIRC) that doesn't
> work. If it did, rtemsReboot()/bsp_reset() or 'exit()' should both
> do the job...
On the mvme5500 and mvme6100 board,  there is a board reset
command which I found from the "programmer's manual".
Perhaps, you can find one for the mvme2700 , too.

Kate

> You should be able to reset the board via a VME sysreset
> (vmeUniverseResetBus())
>
> -- T.
> > I've shown gdb output below. This is running on an MVME-2700.
> >
> > Thanks,
> > -Matt
> >
> > EPICS 3.14.10 /RTEMS 4.9.1
> > ------
> > 10.1.5.253> exit
> > Printing a stack trace for your convenience :-)
> >
> > 0x0011A8E0--> 0x0010F55C--> 0x0010A888--> 0x0010A76C--> 0x0000322C
> >
> >
> > gdb shows:
> > (gdb) x 0x0000322C
> >
> > 0x322c <enter_C_code+68>:       0x4800004d
> >
> > (gdb)
> >
> > 0x3230 <MMUon>: 0x7c0000a6
> >
> > (gdb)
> >
> > 0x3234 <MMUon+4>:       0x6000a972
> >
> > (gdb)
> >
> > 0x3238 <MMUon+8>:       0x68008940
> >
> > (gdb)
> >
> > 0x323c <MMUon+12>:      0x7d6802a6
> >
> > (gdb)
> >
> > 0x3240 <MMUon+16>:      0x7d7a03a6
> >
> > (gdb)
> >
> > 0x3244 <MMUon+20>:      0x7c1b03a6
> >
> > (gdb)
> >
> > 0x3248 <MMUon+24>:      0x7c0004ac
> >
> > (gdb)
> >
> > 0x324c <MMUon+28>:      0x4c00012c
> >
> > (gdb)
> >
> > 0x3250 <MMUon+32>:      0x4c000064
> >
> > (gdb)
> >
> > 0x3254 <MMUoff>:        0x7c0000a6
> >
> > (gdb)
> >
> > 0x3258 <MMUoff+4>:      0x60000070
> >
> > (gdb)
> > 0x325c <MMUoff+8>:      0x7d6802a6
> > (gdb)
> > 0x3260 <MMUoff+12>:     0x68000030
> > (gdb)
> > 0x3264 <MMUoff+16>:     0x7d7a03a6
> > (gdb)
> > 0x3268 <MMUoff+20>:     0x7c1b03a6
> > (gdb)
> > 0x326c <MMUoff+24>:     0x7c0004ac
> > (gdb)
> > 0x3270 <MMUoff+28>:     0x4c00012c
> > (gdb)
> > 0x3274 <MMUoff+32>:     0x4c000064
> > (gdb)
> > 0x3278 <_return_to_ppcbug>:     0x7fc802a6
> > (gdb)