On Wed, May 09, 2012 at 03:44:08PM -0500, Buckley, Bryan wrote: > On Wed, May 9, 2012 at 10:48 AM, Russell King - ARM Linux > <linux@xxxxxxxxxxxxxxxx> wrote: > > > > On Wed, May 09, 2012 at 06:00:10PM +0530, Shilimkar, Santosh wrote: > > > On Wed, May 9, 2012 at 5:53 PM, Russell King - ARM Linux > > > <linux@xxxxxxxxxxxxxxxx> wrote: > > > > On Wed, May 09, 2012 at 02:20:28PM +0530, Shilimkar, Santosh wrote: > > > >> The only change done common code is clearing 'XN' bit for DRAM > > > >> region in page table entries. The other change of setting the DACR > > > >> register is done in ARMv7 specific code. > > > > > > > > Yes, XN is an ARMv6+ thing. Before ARMv5, it was implementation defined. > > > > > > > > Some implementations used the bit to mean "allow writes to update the > > > > cache". Other implementations labelled this bit as "should be zero" > > > > while others labelled it as "should be one". > > > > > > > Good to know. > > > > > > > The upshot of this is, we know that having this bit as '1' means that > > > > all the CPUs we support today work. I would be _very_ concerned to > > > > change this bit to zero as we _really_ don't know how the pre-ARMv6 > > > > CPUs would react. > > > > > > > I agree. > > > > > > > The solution to this is pretty simple - if ARMv6+ needs a different > > > > base section mapping value, then we need to extract that from the code > > > > and pass in the base section mapping value. > > > > > > > > I'll sort out a patch later today for this. > > > Great. > > > > This works for my 4430SDP board. I haven't booted it on anything else yet. > > Please can you check that this solves the issue for you? Thanks. > > > > Solves the issue for OMAP5. Thanks Russel and company. Can I add this attributation for this patch: Tested-by: Bryan Buckley <bryan.buckley@xxxxxx> ? -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
