public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
From: David Gibson <david@gibson•dropbear.id.au>
To: Yoder Stuart-B08248 <stuart.yoder@freescale•com>
Cc: linuxppc-dev@ozlabs•org
Subject: Re: [PATCH 15/16] Add device tree for Ebony
Date: Thu, 15 Feb 2007 10:27:01 +1100	[thread overview]
Message-ID: <20070214232701.GF16279@localhost.localdomain> (raw)
In-Reply-To: <9696D7A991D0824DBA8DFAC74A9C5FA302A1B86F@az33exm25.fsl.freescale.net>

On Wed, Feb 14, 2007 at 01:08:01PM -0700, Yoder Stuart-B08248 wrote:
>  
> > >> Hmm.  There are two "soc" devices here, one nested under the
> > >> first??
> > >>
> > >> I'm assuming these are two levels of busses the opb bus is attached
> > >> to the plb bus.  Is the "soc" device_type the right way to
> > >> do this?
> > >
> > > Right, OPB hangs off of PLB in this case.  I dunno if "soc" is the 
> > > right
> > > device type for them though.
> > 
> > I would use device_type "plb" (or "plb4") and "opb" I think.
> > Similar to how PCI and ISA etc. busses are represented.
> 
> I think we should avoid making up new device_types unlesss it
> really is necessary.
> 
> Is it really necessary to distinguish between devices on
> the PLB or OPB?

Well.. maybe.  There are registers (DCR, not MMIO) in the PLB<->OPB
bridge.  I don't think the actual mapping can be changed, but some
error reporting and arbitration are controller there.  I think it's
better to represent the two busses, in case the distinction becomes
important at some point.

> As I undestand it the "soc" device type is a logical container
> for a group of devices in an SOC, not necessarily a group
> of devices on the same bus.  Could we simply list all those
> devices under an "soc" node at the same level.
> 
> If for some reason the bus hierarchy distinction _is_ required,
> my suggestion would be to create new generic device type for
> representing an internal bus.   The "device_type" is supposed
> to be somewhat general-- "network", "serial", etc.
> 
> We could create something like "soc-bus" or "internal-bus" with
> a compatible field that identifies the type of bus.
> 
> The general philosophy is a general device_type prooperty and
> a specific compatible property.

Yes, that's partly why I'm using "soc" for now.  I've thought that a
new general device_type might be a good idea though.  What's a "soc"
and what's an "internal" bus I think are not necessarily clear,
though.  I would suggest a type for any memory mapped,
non-hotpluggable, non-probeable bus.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

  parent reply	other threads:[~2007-02-14 23:27 UTC|newest]

Thread overview: 111+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-02-13  6:09 [0/16] Preliminary Ebony (440GP) support for arch/powerpc David Gibson
2007-02-13  6:10 ` [PATCH 6/16] Port 44x MMU definitions to ARCH=powerpc David Gibson
2007-02-13  6:24   ` Benjamin Herrenschmidt
2007-02-13 17:13     ` Roland Dreier
2007-02-13 17:45       ` Josh Boyer
2007-02-13 21:36       ` Benjamin Herrenschmidt
2007-02-13  6:10 ` [PATCH 2/16] More DCR native fixups David Gibson
2007-02-13  6:22   ` Benjamin Herrenschmidt
2007-02-13  6:10 ` [PATCH 8/16] Define FIXED_PORT flag for serial_core David Gibson
2007-02-13  6:10 ` [PATCH 4/16] powerpc: Allow duplicate lmb_reserve() calls David Gibson
2007-02-13  7:05   ` Michael Neuling
2007-02-13  8:48     ` Michael Ellerman
2007-02-13 20:44     ` Benjamin Herrenschmidt
2007-02-13  6:10 ` [PATCH 5/16] powerpc: Add zImage platform hook for kernel address David Gibson
2007-02-13  6:10 ` [PATCH 1/16] Remove ibm4{xx,4x}.h from arch/powerpc David Gibson
2007-02-13 14:19   ` Josh Boyer
2007-02-13  6:10 ` [PATCH 3/16] [powerpc] Use udbg_early_init() on ppc32 David Gibson
2007-02-13  6:22   ` Benjamin Herrenschmidt
2007-02-13  6:10 ` [PATCH 7/16] Early serial debug support for PPC44x David Gibson
2007-02-13 15:04   ` Josh Boyer
2007-02-14  0:16     ` David Gibson
2007-02-14  1:02       ` Josh Boyer
2007-02-14  1:00         ` David Gibson
2007-02-14  2:00           ` Alan Modra
2007-02-14  2:02             ` David Gibson
2007-02-14  2:38               ` Alan Modra
2007-02-14 15:41                 ` Josh Boyer
2007-02-14 23:05                   ` David Gibson
2007-02-13  6:10 ` [PATCH 13/16] Add initrd properties to device tree from zImage David Gibson
2007-02-13  6:10 ` [PATCH 9/16] Use resource_size_t for serial port IO addresses David Gibson
2007-02-13  6:10 ` [PATCH 11/16] zImage wrapper for Ebony David Gibson
2007-02-13 17:05   ` Geoff Levand
2007-02-14  0:17     ` David Gibson
2007-02-13  6:10 ` [PATCH 14/16] Add arch/powerpc driver for UIC, PPC4xx interrupt controller David Gibson
2007-02-13  6:10 ` [PATCH 10/16] Add support for BSS stack for zImage wrapper David Gibson
2007-02-13  6:10 ` [PATCH 12/16] Automatically lmb_reserve() initrd David Gibson
2007-02-13  7:14   ` Michael Neuling
2007-02-13  6:10 ` [PATCH 15/16] Add device tree for Ebony David Gibson
2007-02-13 20:08   ` Segher Boessenkool
2007-02-14  0:22     ` David Gibson
2007-02-14  1:51       ` Benjamin Herrenschmidt
2007-02-14  4:46         ` David Gibson
2007-02-14 17:54           ` Segher Boessenkool
2007-02-14 23:18             ` David Gibson
2007-02-15  0:25               ` Segher Boessenkool
2007-02-14 17:51         ` Segher Boessenkool
2007-02-14 17:48       ` Segher Boessenkool
2007-02-14 21:30         ` Benjamin Herrenschmidt
2007-02-15  0:03           ` Segher Boessenkool
2007-02-15  0:53             ` Benjamin Herrenschmidt
2007-02-15  1:00               ` Segher Boessenkool
2007-02-15  2:22                 ` Benjamin Herrenschmidt
2007-02-15  2:51                   ` Segher Boessenkool
2007-02-14 23:17         ` David Gibson
2007-02-15  0:27           ` Segher Boessenkool
2007-02-15 14:02             ` Jon Loeliger
2007-02-15 14:56               ` Segher Boessenkool
2007-02-15 17:02                 ` Yoder Stuart-B08248
2007-02-15 17:10                   ` Scott Wood
2007-02-16  9:20                   ` Segher Boessenkool
2007-02-14 16:14   ` Yoder Stuart-B08248
2007-02-14 16:32     ` Josh Boyer
2007-02-14 17:58       ` Segher Boessenkool
2007-02-14 20:08         ` Yoder Stuart-B08248
2007-02-14 21:12           ` Segher Boessenkool
2007-02-14 21:35             ` Yoder Stuart-B08248
2007-02-14 21:42               ` Benjamin Herrenschmidt
2007-02-14 21:59                 ` Scott Wood
2007-02-15  0:20                   ` Segher Boessenkool
2007-02-14 22:50                 ` Yoder Stuart-B08248
2007-02-14 22:57                   ` Benjamin Herrenschmidt
2007-02-15  0:17                 ` Segher Boessenkool
2007-02-15  2:12                   ` Paul Mackerras
2007-02-15  2:43                     ` Segher Boessenkool
2007-02-15  3:15                       ` Paul Mackerras
2007-02-15 14:40                         ` Segher Boessenkool
2007-02-16  1:17                           ` Paul Mackerras
2007-02-16  9:41                             ` Segher Boessenkool
2007-02-15  0:10               ` Segher Boessenkool
2007-02-14 23:32             ` David Gibson
2007-02-14 23:27           ` David Gibson [this message]
2007-02-14 23:22         ` David Gibson
2007-02-14 23:51           ` Benjamin Herrenschmidt
2007-02-15  0:36             ` Segher Boessenkool
2007-02-15  0:31           ` Segher Boessenkool
2007-02-15  1:53             ` David Gibson
2007-02-15  3:09               ` Segher Boessenkool
2007-02-15  3:33                 ` David Gibson
2007-02-15 14:47                   ` Segher Boessenkool
2007-02-15 10:52                 ` Benjamin Herrenschmidt
2007-02-15 14:52                   ` Segher Boessenkool
2007-02-15 20:43                     ` Benjamin Herrenschmidt
2007-02-16  9:23                       ` Segher Boessenkool
2007-02-15 16:37                 ` Yoder Stuart-B08248
2007-02-15 21:41                   ` Benjamin Herrenschmidt
2007-02-16  9:25                     ` Segher Boessenkool
2007-02-16 15:32                     ` Hartmut Penner
2007-02-16 16:47                       ` Yoder Stuart-B08248
2007-02-19 12:02                         ` Hartmut Penner
2007-02-14 21:29       ` Benjamin Herrenschmidt
2007-02-13  6:10 ` [PATCH 16/16] Support for Ebony in arch/powerpc David Gibson
2007-02-13 17:18   ` Roland Dreier
2007-02-14  0:20     ` David Gibson
2007-02-13 14:37 ` [0/16] Preliminary Ebony (440GP) support for arch/powerpc Josh Boyer
2007-02-13 20:21   ` Josh Boyer
2007-02-13 15:46 ` Josh Boyer
2007-02-14 16:06   ` Josh Boyer
2007-02-14 23:12     ` David Gibson
2007-02-16  2:19       ` Josh Boyer
2007-02-16  2:53         ` David Gibson
2007-02-16  4:33           ` Josh Boyer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20070214232701.GF16279@localhost.localdomain \
    --to=david@gibson$(echo .)dropbear.id.au \
    --cc=linuxppc-dev@ozlabs$(echo .)org \
    --cc=stuart.yoder@freescale$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox