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Date: Fri, 5 Feb 2016 14:08:23 -0600
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Subject: Re: [PATCH] mtd/ifc: Add support for IFC controller version 2.0
From: Li Yang <leoli@freescale.com>
To: Scott Wood <oss@buserror.net>
Cc: prabhakar.kushwaha@nxp.com, linux-mtd@lists.infradead.org,
 Brian Norris <computersforpeace@gmail.com>,
 linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
 Raghav Dogra <raghav@freescale.com>, Jaiprakash Singh <b44839@freescale.com>
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On Fri, Feb 5, 2016 at 12:23 PM, Scott Wood <oss@buserror.net> wrote:
> On Fri, 2016-02-05 at 12:05 -0600, Li Yang wrote:
>> On Thu, Feb 4, 2016 at 7:17 PM, Scott Wood <oss@buserror.net> wrote:
>> > On Thu, 2016-02-04 at 17:07 -0600, Li Yang wrote:
>> > > On Wed, Feb 3, 2016 at 12:36 AM, Raghav Dogra <raghav@freescale.com>
>> > > wrote:
>> > > > The new IFC controller version 2.0 has a different memory map page.
>> > > > Upto IFC 1.4 PAGE size is 4 KB and from IFC2.0 PAGE size is 64KB.
>> > > > This patch segregates the IFC global and runtime registers to
>> > > > appropriate
>> > > > PAGE sizes.
>> > >
>> > > If the global registers and the runtime registers are so independent
>> > > that they have to be on different page boundaries, it would make more
>> > > sense for them to be defined as separate reg regions in the device
>> > > tree at the very beginning.  Then we would only need to change the
>> > > device tree now and it would be future proof for any page size.
>> >
>> > That's great if you have a time machine.  Otherwise, NACK.
>>
>> I didn't suggest that we need to change it now.  But we might need to
>> be more careful in the future when creating bindings for new hardware.
>
> At the time the binding was created there was no reason to believe that the
> layout would change.

Probably separate blocks that intentionally start from a page
boundary(with big gaps before it) would be a good idea?

Regards,
Leo