exynos4412 hangs on enabling MMU

[Ruslan Bukin]

On Tue, Oct 30, 2012 at 10:08:21AM -0600, Warner Losh wrote:
> 
> > On Tue, 2012-10-30 at 16:32 +0400, Ruslan Bukin wrote:
> >> hello!
> >> 
> >> exynos hangs on mcr cmd in this context:
> >> 
> >> /* Enable MMU */
> >> [..]
> >> orr     r0, r0, #(CPU_CONTROL_MMU_ENABLE | CPU_CONTROL_DC_ENABLE)
> >> mcr     p15, 0, r0, c1, c0, 0
> >> [..]
> >> 
> >> without CPU_CONTROL_MMU_ENABLE flag, mcr command works,
> >> but board hangs again on line:
> >> str r3, [r1], #0x0004 /* get zero init data */
> >> 
> >> any suggestions?
> >> 
> >> -Ruslan
> > 
>
> I'd be interested in tracking that down...  I've been booting lots of armv5 boards lately and haven't seen this hang with current.


just read CPU_CONTROL_MMU_ENABLE bit from arm using mrc command, and 
it shows that MMU is enabled after mcr cmd (without using CPU_CONTROL_MMU_ENABLE bit),
and disabled before. So MMU switch seems works.

but board still hangs on line:
str r3, [r1], #0x0004 /* get zero init data */

-Ruslan