RE: [PATCH v3 0/4] powerpc: Open PIC binding and "pic-no-reset"

-----Original Message-----
From: Meador Inge [mailto:meadori@gmail.com]
Sent: Thursday, February 10, 2011 9:26 PM
To: Benjamin Herrenschmidt
Cc: Yoder Stuart-B08248; devicetree-discuss@lists.ozlabs.org; linuxppc-
dev@lists.ozlabs.org
Subject: Re: [PATCH v3 0/4] powerpc: Open PIC binding and "pic-no-reset"
=20
Apologies for the bad post. =A0Bad day for email ... =A0Please ignore the=

 top

reply in my previous reply. =A0The full reply is the below the quote.
=20
On Thu, Feb 10, 2011 at 8:01 PM, Meador Inge [off-list ref]
wrote:

quoted

On 02/10/2011 02:42 PM, Meador Inge wrote:

quoted

---------- Forwarded message ----------
From: Meador Inge<redacted>
Date: Fri, Feb 4, 2011 at 5:25 PM
Subject: [PATCH v3 0/4] powerpc: Open PIC binding and "pic-no-reset"
To: linuxppc-dev@lists.ozlabs.org
Cc: devicetree-discuss@lists.ozlabs.org, Hollis Blanchard<
hollis_blanchard@mentor.com>


This patch set provides a binding for Open PIC and implements support
for a new property, specified by that binding, called "pic-no-reset".
With "pic-no-reset" in place the "protected-sources" property is no
longer needed and its full implementation was removed.
"protected-sources" is still checked for, however, for legacy
purposes.

For v3 of this patch the Open PIC binding was changed to be more
consistent with existing bindings, several DTS files were cleaned up,
"no-reset" was changed to "pic-no-reset", and a check to treat
"protected-sources" as a synonym for "pic-no-reset" was added.

=20
From the feedback I have received so far, the fundamental ideas in this
patch set are sane. =A0However, the following issues still need agreement=

:

=20
 =A0 =A01. What should be the name of the no reset property?
 =A0 =A0 =A0 "pic-no-reset" or "no-reset"?
 =A0 =A02. Should we just keep the existing protected sources implementat=

ion

 =A0 =A0 =A0 in place?
=20
For (1), I prefer "no-reset".

I also prefer plain "no-reset".  The property is on a pic node so
"pic" on the property seems redundant.

For (2), I still think that we can make "no-
reset" a synonym for "protected-sources" and that things will work out.
=20
Ben, you said that you would really like to leave the protected sources
implementation alone. =A0Is the mechanism implemented in "PATCH
v3 3/4" [1] of having "protected-sources" as a synonym for "pic-no-reset"
not suitable?

I thought what Ben was getting at was that there is existing
firmware that may provide a device tree with protected-sources,
and thus we should continue supporting it for backwards
compatibility.

So, I would say add "no-reset" as the preferred mechanism
going forward, but keep "protected-sources" for backwards
compatibility.

Stuart

On Fri, 11 Feb 2011 14:58:13 +0000
Yoder Stuart-B08248 [off-list ref] wrote:

=20
=20

quoted

-----Original Message-----
From: Meador Inge [mailto:meadori@gmail.com]
Sent: Thursday, February 10, 2011 9:26 PM
To: Benjamin Herrenschmidt
Cc: Yoder Stuart-B08248; devicetree-discuss@lists.ozlabs.org; linuxppc-
dev@lists.ozlabs.org
Subject: Re: [PATCH v3 0/4] powerpc: Open PIC binding and "pic-no-reset"
=20
From the feedback I have received so far, the fundamental ideas in this
patch set are sane. =C2=A0However, the following issues still need agre=

ement:

quoted

=20
 =C2=A0 =C2=A01. What should be the name of the no reset property?
 =C2=A0 =C2=A0 =C2=A0 "pic-no-reset" or "no-reset"?
 =C2=A0 =C2=A02. Should we just keep the existing protected sources imp=

lementation

quoted

 =C2=A0 =C2=A0 =C2=A0 in place?
=20
For (1), I prefer "no-reset".

=20
I also prefer plain "no-reset".  The property is on a pic node so
"pic" on the property seems redundant.

It's not redundant, it's namespacing.  Before there was a generic "status"
property, someone who wanted a device-specific "status" could have made
the same argument.  Usually we use a vendor prefix to avoid that problem,
but that won't work here.

-Scott

On Fri, Feb 11, 2011 at 11:41 AM, Scott Wood [off-list ref] wrot=
e:

On Fri, 11 Feb 2011 14:58:13 +0000
Yoder Stuart-B08248 [off-list ref] wrote:

quoted

quoted

-----Original Message-----
From: Meador Inge [mailto:meadori@gmail.com]
Sent: Thursday, February 10, 2011 9:26 PM
To: Benjamin Herrenschmidt
Cc: Yoder Stuart-B08248; devicetree-discuss@lists.ozlabs.org; linuxppc=

-

quoted

quoted

dev@lists.ozlabs.org
Subject: Re: [PATCH v3 0/4] powerpc: Open PIC binding and "pic-no-rese=

t"

quoted

quoted

From the feedback I have received so far, the fundamental ideas in thi=

s

quoted

quoted

patch set are sane. =A0However, the following issues still need agreem=

ent:

quoted

quoted

=A0=A0 =A01. What should be the name of the no reset property?
=A0=A0 =A0 =A0 "pic-no-reset" or "no-reset"?
=A0=A0 =A02. Should we just keep the existing protected sources implem=

entation

quoted

quoted

=A0=A0 =A0 =A0 in place?

For (1), I prefer "no-reset".

I also prefer plain "no-reset". =A0The property is on a pic node so
"pic" on the property seems redundant.

It's not redundant, it's namespacing. =A0Before there was a generic "stat=

us"

property, someone who wanted a device-specific "status" could have made
the same argument. =A0Usually we use a vendor prefix to avoid that proble=

m,

but that won't work here.

Yes, it is a namespace issue.  Please keep the 'pic-' or some other
prefix to reduce the likelyhood of a global namespace clash.
'no-reset' is vanilla enough that it is conceivable it could be
defined as part of a common binding sometime in the future.

g.