how to use head_fsl_booke.S:abort to restart

how to use head_fsl_booke.S:abort to restart

[Philippe De Muyter]

Hi all,

I have a mpc8540 board that could reboot when driven by a ARCH=ppc linux,
but that hangs now in arch/powerpc/sysdev/fsl_soc.c:fsl_rstcr_restart when
asked to reboot with a ARCH=powerpc linux.

I have found that if I call arch/powerpc/kernel/head_fsl_booke.S:abort from
there, my board reboots correctly, but I feel that's not the right place
to put that call.  Where/how should I do that ?

Philippe

PS : Does arch/powerpc/sysdev/fsl_soc.c:fsl_rstcr_restart actually work
for mpc8540_ads boards ?

Re: how to use head_fsl_booke.S:abort to restart

[Haiying Wang]

8540 doesn't have RSTCR register. You should not use fsl_rstcr_restart
for reboot your 8540 board.

Haiying

On Tue, 2008-03-25 at 17:15 +0100, Philippe De Muyter wrote:
> Hi all,
> 
> I have a mpc8540 board that could reboot when driven by a ARCH=ppc linux,
> but that hangs now in arch/powerpc/sysdev/fsl_soc.c:fsl_rstcr_restart when
> asked to reboot with a ARCH=powerpc linux.
> 
> I have found that if I call arch/powerpc/kernel/head_fsl_booke.S:abort from
> there, my board reboots correctly, but I feel that's not the right place
> to put that call.  Where/how should I do that ?
> 
> Philippe
> 
> PS : Does arch/powerpc/sysdev/fsl_soc.c:fsl_rstcr_restart actually work
> for mpc8540_ads boards ?
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@ozlabs.org
> https://ozlabs.org/mailman/listinfo/linuxppc-dev

Re: how to use head_fsl_booke.S:abort to restart

[Philippe De Muyter]

Hi Haiying,

On Tue, Mar 25, 2008 at 12:34:55PM -0400, Haiying Wang wrote:
> 8540 doesn't have RSTCR register. You should not use fsl_rstcr_restart
> for reboot your 8540 board.
> 
That's what I was thinking also (see my Post-Scriptum below), but current
linux/powerpc sources use fsl_rstcr_restart for the mpc8540_ads board :( 

Philippe

> On Tue, 2008-03-25 at 17:15 +0100, Philippe De Muyter wrote:
> > Hi all,
> > 
> > I have a mpc8540 board that could reboot when driven by a ARCH=ppc linux,
> > but that hangs now in arch/powerpc/sysdev/fsl_soc.c:fsl_rstcr_restart when
> > asked to reboot with a ARCH=powerpc linux.
> > 
> > I have found that if I call arch/powerpc/kernel/head_fsl_booke.S:abort from
> > there, my board reboots correctly, but I feel that's not the right place
> > to put that call.  Where/how should I do that ?
> > 
> > Philippe
> > 
> > PS : Does arch/powerpc/sysdev/fsl_soc.c:fsl_rstcr_restart actually work
> > for mpc8540_ads boards ?

Re: how to use head_fsl_booke.S:abort to restart

[Haiying Wang]

Ok, I see the problem here. For 8540/60 which has e500 v1 core, it
doesn't use RSTCR to assert HRESET_REQ signal to reset the whole system.
We probably need to add abort() in fsl_rstcr_restart() for those
silicons:

diff --git a/arch/powerpc/sysdev/fsl_soc.c
b/arch/powerpc/sysdev/fsl_soc.c
index 2c5388c..c2d07cd 100644
--- a/arch/powerpc/sysdev/fsl_soc.c
+++ b/arch/powerpc/sysdev/fsl_soc.c
@@ -1434,7 +1434,8 @@ void fsl_rstcr_restart(char *cmd)
        if (rstcr)
                /* set reset control register */
                out_be32(rstcr, 0x2);   /* HRESET_REQ */
-
+       else
+               abort();
        while (1) ;
 }
 #endif

I don't have 8540 board to test.

Haiying


On Tue, 2008-03-25 at 21:20 +0100, Philippe De Muyter wrote:
> Hi Haiying,
> 
> On Tue, Mar 25, 2008 at 12:34:55PM -0400, Haiying Wang wrote:
> > 8540 doesn't have RSTCR register. You should not use fsl_rstcr_restart
> > for reboot your 8540 board.
> > 
> That's what I was thinking also (see my Post-Scriptum below), but current
> linux/powerpc sources use fsl_rstcr_restart for the mpc8540_ads board :( 
> 
> Philippe
> 
> > On Tue, 2008-03-25 at 17:15 +0100, Philippe De Muyter wrote:
> > > Hi all,
> > > 
> > > I have a mpc8540 board that could reboot when driven by a ARCH=ppc linux,
> > > but that hangs now in arch/powerpc/sysdev/fsl_soc.c:fsl_rstcr_restart when
> > > asked to reboot with a ARCH=powerpc linux.
> > > 
> > > I have found that if I call arch/powerpc/kernel/head_fsl_booke.S:abort from
> > > there, my board reboots correctly, but I feel that's not the right place
> > > to put that call.  Where/how should I do that ?
> > > 
> > > Philippe
> > > 
> > > PS : Does arch/powerpc/sysdev/fsl_soc.c:fsl_rstcr_restart actually work
> > > for mpc8540_ads boards ?

Re: how to use head_fsl_booke.S:abort to restart

[Philippe De Muyter]

Hi Haiying,

On Tue, Mar 25, 2008 at 04:48:23PM -0400, Haiying Wang wrote:
> Ok, I see the problem here. For 8540/60 which has e500 v1 core, it
> doesn't use RSTCR to assert HRESET_REQ signal to reset the whole system.
> We probably need to add abort() in fsl_rstcr_restart() for those
> silicons:
> 
> diff --git a/arch/powerpc/sysdev/fsl_soc.c
> b/arch/powerpc/sysdev/fsl_soc.c
> index 2c5388c..c2d07cd 100644
> --- a/arch/powerpc/sysdev/fsl_soc.c
> +++ b/arch/powerpc/sysdev/fsl_soc.c
> @@ -1434,7 +1434,8 @@ void fsl_rstcr_restart(char *cmd)
>         if (rstcr)
>                 /* set reset control register */
>                 out_be32(rstcr, 0x2);   /* HRESET_REQ */
> -
> +       else
> +               abort();
>         while (1) ;
>  }
>  #endif

I have a 8540 board, and that works, but as your patch is written,
compilation fails with :

	arch/powerpc/sysdev/fsl_soc.c: In function 'fsl_rstcr_restart':
	arch/powerpc/sysdev/fsl_soc.c:1445: error: implicit declaration
	of function 'abort'
	arch/powerpc/sysdev/fsl_soc.c:1445: warning: incompatible implicit
	declaration of built-in function 'abort'
	make[1]: *** [arch/powerpc/sysdev/fsl_soc.o] Error 1
	make: *** [arch/powerpc/sysdev] Error 2

and if I fix that with :

	 arch_initcall(setup_rstcr);

	+extern void abort(void);
	+
	 void fsl_rstcr_restart(char *cmd)
	 {

it compiles and does reboot, but at startup I still get the following
annoying message :

	rstcr compatible register does not exist!

Philippe