public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
From: Mitch Bradley <wmb@firmworks•com>
To: Benjamin Herrenschmidt <benh@kernel•crashing.org>
Cc: microblaze-uclinux@itee•uq.edu.au,
	Dan Malek <ppc6dev@digitaldans•com>,
	devicetree-discuss <devicetree-discuss@lists•ozlabs.org>,
	Jeremy Kerr <jeremy.kerr@canonical•com>,
	linuxppc-dev <linuxppc-dev@ozlabs•org>
Subject: Re: Request review of device tree documentation
Date: Fri, 11 Jun 2010 18:48:21 -1000	[thread overview]
Message-ID: <4C131195.1000009@firmworks.com> (raw)
In-Reply-To: <1276311487.1962.172.camel@pasglop>

Benjamin Herrenschmidt wrote:
> On Fri, 2010-06-11 at 16:47 -0700, Dan Malek wrote:
>   
>> Hi Grant.
>>
>> On Jun 11, 2010, at 3:59 PM, Grant Likely wrote:
>>
>>     
>>> I've been doing a bit of work on some introductory level documentation
>>> of the flattened device tree.
>>>       
>> Wow, I feel empowered to create device trees now :-)
>> Seriously, I never understood this well and this is a
>> great document.
>>
>> I have one source of confusion.  Your first Initial structure
>> example uses 'compatible' to describe the machine, the
>> paragraph below then mentions the 'model' property,
>> and all subsequent examples use model.
>>
>> Does this mean if I use just the single line in the dts,
>> using 'compatible' implies the ARM machine ID?  If I
>> have more description I use 'model'?
>>     
>
> Normally, "compatible" is what is used for code to match,
> and model is more like a user-visible thingy.
>   

Indeed, one common use of "model" - at least in the systems I work on - 
is to display the name of the machine in a system identification banner 
that the user sees.
> It's possible to peek at 'model' tho, in some cases, I've seen the case
> for example where things are -supposed- to be identical from an arch
> point of view, have the same compatible, but later on, a quirk is found
> and a test against model is used to differentiate. But that's something
> to avoid in general. Better off having multiple strings in "compatible"
> then, one more "generic" to have the BSP match against, and one more
> "specific" that can be used if a quirk is needed.
>
> Of course, it doesn't help that all pseries have "chrp" and nothing else
> as compatible :-) But then, both IBM and Apple have been quite lax with
> their (ab)use of the DT.
>
> Cheers,
> Ben.
>
>
> _______________________________________________
> devicetree-discuss mailing list
> devicetree-discuss@lists•ozlabs.org
> https://lists.ozlabs.org/listinfo/devicetree-discuss
>
>   

  reply	other threads:[~2010-06-12  4:48 UTC|newest]

Thread overview: 75+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-06-11 22:59 Request review of device tree documentation Grant Likely
2010-06-11 23:47 ` Dan Malek
2010-06-12  2:58   ` Benjamin Herrenschmidt
2010-06-12  4:48     ` Mitch Bradley [this message]
2010-06-12  6:53   ` Grant Likely
2010-06-12  8:19     ` Mitch Bradley
2010-06-12 10:45       ` Benjamin Herrenschmidt
2010-06-12 10:48         ` Benjamin Herrenschmidt
2010-06-12 16:30           ` Mitch Bradley
2010-06-12 22:52             ` Benjamin Herrenschmidt
2010-06-13  5:07               ` Grant Likely
2010-06-13  5:39                 ` Mitch Bradley
2010-06-13  5:59                   ` Benjamin Herrenschmidt
2010-06-13  6:45                     ` Mitch Bradley
2010-06-13  8:29                       ` Benjamin Herrenschmidt
2010-06-14  5:36                         ` Grant Likely
2010-06-14 20:00                           ` Ben Dooks
2010-06-13  8:57                       ` Benjamin Herrenschmidt
2010-06-14  5:23                     ` Grant Likely
2010-06-14  7:38                       ` Russell King - ARM Linux
2010-06-14  7:45                         ` Mitch Bradley
2010-06-14  9:25                           ` Russell King - ARM Linux
2010-06-14  9:36                             ` Benjamin Herrenschmidt
2010-06-14  9:47                               ` Russell King - ARM Linux
2010-06-14 14:29                                 ` Jamie Lokier
2010-06-14 13:51                       ` Nicolas Pitre
2010-06-14 15:35                         ` Grant Likely
2010-06-14 15:58                           ` Nicolas Pitre
2010-06-14 16:16                             ` Grant Likely
2010-06-14  5:02                   ` Grant Likely
2010-06-14 12:44                     ` David Gibson
2010-06-14 14:59                       ` Nicolas Pitre
2010-06-14 15:08                         ` Grant Likely
2010-06-14 16:02                         ` Jamie Lokier
2010-06-14 16:23                           ` Nicolas Pitre
2010-06-14 16:29                             ` Grant Likely
2010-06-14 16:28                           ` Grant Likely
2010-06-14 16:33                             ` Jamie Lokier
2010-06-14 16:58                           ` Mitch Bradley
2010-06-14 17:26                             ` Nicolas Pitre
2010-06-14 18:20                               ` Mitch Bradley
2010-06-14 19:40                                 ` Nicolas Pitre
2010-06-14 20:08                                   ` Mark Brown
2010-06-16  6:09                             ` Mike Rapoport
2010-06-16  6:13                               ` Mitch Bradley
2010-06-16  6:17                                 ` Mike Rapoport
2010-06-16  6:32                                   ` Mitch Bradley
2010-06-16  6:47                                     ` Mike Rapoport
2010-06-16  7:40                                       ` Mitch Bradley
2010-06-16  9:45                                         ` Vladimir Pantelic
2010-06-16 10:39                                         ` Mike Rapoport
2010-06-16 11:41                                           ` Jamie Lokier
2010-06-16 13:48                                             ` Jamie Bennett
2010-06-16 14:39                                           ` Nicolas Pitre
2010-06-16 17:43                                             ` Tim Bird
2010-06-16  6:52                                     ` M. Warner Losh
2010-06-18 22:12                                       ` Frank Rowand
2010-06-15  2:02                         ` David Gibson
2010-06-14 15:51                       ` M. Warner Losh
2010-06-13  5:48                 ` Benjamin Herrenschmidt
2010-06-14  5:13                   ` Grant Likely
2010-06-14  6:09                     ` Benjamin Herrenschmidt
2010-06-14  6:17                       ` Mitch Bradley
2010-06-12 22:15     ` Olof Johansson
2010-06-12 23:09       ` Grant Likely
2010-06-13  6:47         ` [microblaze-uclinux] " Edgar E. Iglesias
2010-06-12  3:00 ` Benjamin Herrenschmidt
2010-06-12  3:07   ` Benjamin Herrenschmidt
2010-06-13 13:12     ` Jeremy Kerr
2010-06-14  5:40       ` Grant Likely
2010-06-12 17:33 ` Stephan Gatzka
2010-06-12 18:19   ` Grant Likely
2010-06-14  5:54   ` Grant Likely
2010-08-05  4:43 ` David Gibson
2010-09-01 16:19   ` Grant Likely

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=4C131195.1000009@firmworks.com \
    --to=wmb@firmworks$(echo .)com \
    --cc=benh@kernel$(echo .)crashing.org \
    --cc=devicetree-discuss@lists$(echo .)ozlabs.org \
    --cc=jeremy.kerr@canonical$(echo .)com \
    --cc=linuxppc-dev@ozlabs$(echo .)org \
    --cc=microblaze-uclinux@itee$(echo .)uq.edu.au \
    --cc=ppc6dev@digitaldans$(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