[U-Boot] p4080ds starts OS with MSR[EE]=1 and DEC armed?

[Scott Wood <scottwood@freescale.com>]

On Mon, 14 Mar 2011 16:25:54 -0500
Kumar Gala <galak@kernel.crashing.org> wrote:

> 
> On Mar 14, 2011, at 1:09 PM, Scott Wood wrote:
> 
> > On Sat, 12 Mar 2011 16:56:09 -0600
> > Kumar Gala <galak@kernel.crashing.org> wrote:
> > 
> >> 
> >> On Mar 3, 2011, at 8:59 AM, Jimi Xenidis wrote:
> >> 
> >>> I was surprised to find myself at the decrement interrupt when running my new stuff.
> >>> That is against ePAPR, right?
> >>> Does u-boot at least make sure that the DEC is set to some large value before it leaps at me?
> >>> I don't mind forcing EE=0 but I'd like to make sure I make it that far into the code :)
> >>> -JX
> >> 
> >> Jimi,
> >> 
> >> Not sure how or why you are seeing this, but u-boot should disable interrupts in common/cmd_bootm.c
> >> 
> >> Look for disable_interrupts() -> this should set MSR[EE] = 0.
> > 
> > What about the rest of MSR -- ME/CE/DE?
> 
> I dont think we ever turn on CE in u-boot, DE would only get set in some weird external debugger build.

From arch/powerpc/cpu/mpc85xx/start.S:

        /* switch back to AS = 0 */
        lis     r3,(MSR_CE|MSR_ME|MSR_DE)@h
        ori     r3,r3,(MSR_CE|MSR_ME|MSR_DE)@l
        mtmsr   r3
        isync

        bl      cpu_init_f
        bl      board_init_f
        isync

-Scott