public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
From: "Mark A. Greer" <mgreer@mvista•com>
To: Tom Rini <trini@kernel•crashing.org>
Cc: linuxppc-dev@ozlabs•org
Subject: Re: [RFC] Option to disable mapping genrtc calls to ppc_md calls
Date: Tue, 18 Jan 2005 11:55:54 -0700	[thread overview]
Message-ID: <41ED5BBA.2090808@mvista.com> (raw)
In-Reply-To: <20050118161515.GI28724@smtp.west.cox.net>

Tom Rini wrote:

>On Mon, Jan 17, 2005 at 02:10:00PM -0700, Mark A. Greer wrote:
>
>  
>
>><snip>
>>
>>There are 2 reasons to not use the ppc_md.get_rtc_time() et. al. interfaces:
>>1) They are called before the i2c driver is initialized and even loaded 
>>if its a module.
>>    
>>
>
>But they check if it's set, so they can be assigned later and this is
>OK.
>

But looking at ppc_md.<anything> automatically makes it ppc only.  
Pretty much any of the rtc chips that we use on ppc platforms could 
appear on almost any other platform with a different processor 
architecture.  So the question is, why do we keep adding ppc-only 
support for rtc chips?  Why are we not putting our effort into making 
code that works on all architectures?  Its easy enough to do...

>>2) Its ppc-specific.  Implementing get_rtc_time() et. al. directly makes 
>>it generic across all architectures.
>>    
>>
>
>Guessing, this is for a marvell chipset that's found on MIPS too.
>

That's an example but like I said above rtc chips are not tied to any 
particular processor architecture.

>>Is there a better way to do this?
>>    
>>
>
>How about we try borrowing the MIPS abstraction and force todc_time,
>pmac_time (any others?) to directly define (and EXPORT_SYMBOL)
>get_rtc_time / set_rtc_time / etc.
>

Yep, MIPS has a solution...and so does ARM...and so does PPC.  This is 
sort of my point.

If we really want to do it right then someone needs to architect a 
generic solution.  What I have done is generic but does not handle the 
case that Geert mentioned when you have one kernel binary and several 
possible rtc chips.  In the meantime, what I have done works fine for 
all but that case.

Mark

  parent reply	other threads:[~2005-01-18 18:56 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-01-17 21:10 [RFC] Option to disable mapping genrtc calls to ppc_md calls Mark A. Greer
2005-01-18  9:20 ` Geert Uytterhoeven
2005-01-18 18:40   ` Mark A. Greer
2005-01-18 19:01     ` Eugene Surovegin
2005-01-18 16:15 ` Tom Rini
2005-01-18 16:25   ` Dan Malek
2005-01-18 17:39     ` Tolunay Orkun
2005-01-18 18:33       ` Tom Rini
2005-01-18 18:13     ` Tom Rini
2005-01-18 18:58       ` Mark A. Greer
2005-01-18 19:08         ` Tom Rini
2005-01-18 19:43           ` Mark A. Greer
2005-01-19 18:08             ` Tom Rini
2005-01-20 20:52               ` Mark A. Greer
2005-01-20 22:53                 ` Tom Rini
2005-01-20 23:21                   ` Mark A. Greer
2005-01-20 23:47                     ` Tom Rini
2005-01-20 23:56                       ` Mark A. Greer
2005-01-18 18:54     ` Eugene Surovegin
2005-01-20 22:27     ` Benjamin Herrenschmidt
2005-01-18 18:55   ` Mark A. Greer [this message]
2005-01-18 19:05     ` Tom Rini
2005-01-18 19:33       ` Mark A. Greer
2005-01-20 22:25 ` Benjamin Herrenschmidt
2005-01-20 23:54   ` Mark A. Greer
2005-01-21  0:01     ` Benjamin Herrenschmidt
2005-01-21  0:09       ` Mark A. Greer
2005-01-21  0:12         ` Benjamin Herrenschmidt
2005-01-21  9:14           ` Geert Uytterhoeven
2005-01-21 14:39             ` Corey Minyard
2005-01-21 22:01             ` Benjamin Herrenschmidt
2005-01-21  9:44         ` Christoph Hellwig

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=41ED5BBA.2090808@mvista.com \
    --to=mgreer@mvista$(echo .)com \
    --cc=linuxppc-dev@ozlabs$(echo .)org \
    --cc=trini@kernel$(echo .)crashing.org \
    /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