On 10/11/18 4:58 AM, Arnd Bergmann wrote:

On Fri, Nov 9, 2018 at 12:48 PM Russell King - ARM Linux
[off-list ref] wrote:

quoted

On Fri, Nov 09, 2018 at 12:40:06PM +0100, Arnd Bergmann wrote:

quoted

On Fri, Nov 9, 2018 at 8:04 AM Chris Packham
[off-list ref] wrote:

quoted

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@alliedtelesis.co.nz>
---

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.

I added ecc-disable because I was modeling it after 
arm,parity-enable/arm,parity-disable. The only reason I can imagine 
wanting to force disable this would be some mis-behaving SoC which has 
it enabled by default in hardware, to my knowledge no such system exists 
(that would use this driver).

I'd be happy to drop the binding an implementation and send a v7 if you 
feel strongly that it marvell,ecc-disable should be removed.