On Fri, Nov 9, 2018 at 12:48 PM Russell King - ARM Linux <linux@xxxxxxxxxxxxxxx> wrote: > > On Fri, Nov 09, 2018 at 12:40:06PM +0100, Arnd Bergmann wrote: > > On Fri, Nov 9, 2018 at 8:04 AM Chris Packham > > <chris.packham@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > > Add documentation for the marvell,ecc-enable and marvell,ecc-disable > > > properties which can be used to enable/disable ECC on the Marvell aurora > > > cache. > > > > > > Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> > > > --- > > > > Why do you need both enable and disable? Wouldn't one of them be enough here? > > It isn't an "on when ecc-enable is present, off when not" because the > current behaviour is to preserve these bits in the control register. > > If we were to implement it as "if no ecc-enable property, turn off > ECC" then that would drastically change the behaviour - systems which > were configured for ECC suddenly lose ECC support. > > Since we don't know which have it and which don't, we can't implement > the option like that. What I meant was why we need support force-disabling it. I understand that we need to allow leaving it at the boot-time default as well as force-enabling it. Arnd