Subject: [PATCH v2 2/7] ARM: virt: allow the kernel to be entered in HYP mode

From: [email-masked] (Tony Lindgren)
Date: Fri, 5 Oct 2012 16:50:46 -0700

* Tony Lindgren <[email-masked]> [121005 16:27]:
> * Russell King - ARM Linux <[email-masked]> [121005 16:10]:
> > On Fri, Oct 05, 2012 at 01:08:22PM -0700, Tony Lindgren wrote:
> > > Just bisected this down in linux-next for breaking booting of
> > > my omap2420 ARMv6 based n8x0..
> > > 
> > > > --- a/arch/arm/kernel/head.S
> > > > +++ b/arch/arm/kernel/head.S
> > > > @@ -83,8 +83,12 @@ ENTRY(stext)
> > > >   THUMB(	.thumb			)	@ switch to Thumb now.
> > > >   THUMB(1:			)
> > > >  
> > > > -	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
> > > > -						@ and irqs disabled
> > > > +#ifdef CONFIG_ARM_VIRT_EXT
> > > > +	bl	__hyp_stub_install
> > > > +#endif
> > > > +	@ ensure svc mode and all interrupts masked
> > > > +	safe_svcmode_maskall r9
> > > > +
> > > >  	mrc	p15, 0, r9, c0, c0		@ get processor id
> > > >  	bl	__lookup_processor_type		@ r5=procinfo r9=cpuid
> > > >  	movs	r10, r5				@ invalid processor (r5=0)?
> > > 
> > > ..and looks like undoing this part fixes it. Any ideas?
> > > 
> > > I quickly tried disabling ARCH_OMAP3 and ARCH_OMAP4 so it's
> > > ARMv6 but that does not help.

The same kernel boots on 2430sdp, which is the same ARMv6 core
as 2430 if I remember correctly. So this hints that it has something
to do with the bits set differently by the bootloader?

Regards,

Tony