[Buildroot] devmem2

[Buildroot] devmem2

[Xianghua Xiao]

Please keep this package, as it's very useful for embedded product
debugging, and it does not take much space at all.
Thanks,
Xianghua

[Buildroot] devmem2

[Bjørn Forsman]

On 21 April 2011 16:17, Xianghua Xiao <xiaoxianghua@gmail.com> wrote:
> Please keep this package, as it's very useful for embedded product
> debugging, and it does not take much space at all.

Busybox provides a similar tool called 'devmem'. Have you tried it?

Best regards,
Bj?rn Forsman

[Buildroot] devmem2

[David Anders]

devmem in busybox is worthless.

it has been "modified" so many times to adhere to the busybox standard that it is not longer a useful item.

Dave

--- On Thu, 4/21/11, Bj?rn Forsman <bjorn.forsman@gmail.com> wrote:

> From: Bj?rn Forsman <bjorn.forsman@gmail.com>
> Subject: Re: [Buildroot] devmem2
> To: "Xianghua Xiao" <xiaoxianghua@gmail.com>
> Cc: buildroot at busybox.net
> Date: Thursday, April 21, 2011, 9:48 AM
> On 21 April 2011 16:17, Xianghua Xiao
> <xiaoxianghua@gmail.com>
> wrote:
> > Please keep this package, as it's very useful for
> embedded product
> > debugging, and it does not take much space at all.
> 
> Busybox provides a similar tool called 'devmem'. Have you
> tried it?
> 
> Best regards,
> Bj?rn Forsman
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

[Buildroot] devmem2

[Peter Korsgaard]

>>>>> "David" == David Anders <dave123_aml@yahoo.com> writes:

 David> devmem in busybox is worthless.

 David> it has been "modified" so many times to adhere to the busybox
 David> standard that it is not longer a useful item.

What do you mean about that? Devmem2 is a very simple program, and the
devmem applet seems to work exactly the same the times I've used it
(except for the access-to-highest-page-issue that got fixed back in
1.16.x).

-- 
Bye, Peter Korsgaard

[Buildroot] devmem2

[David Anders]

Peter,

the primary commit that makes the devmem applet unusable for most debugging is this one:

commit 043246560fcd5bb7bfb2caa2db270c3c0e8e06f4
Author: Denis Vlasenko <vda.linux@googlemail.com>
Date:   Sun Oct 26 17:26:55 2008 +0000

    devmem: make it more script-friendly; don't do any reads
     and output nothing if writing was requested. -100 bytes


for board bring up and general development, for which devmem is primarily used, having devmem report the value before the write is important, as well as reporting the value after the write.

Dave



--- On Tue, 4/26/11, Peter Korsgaard <jacmet@uclibc.org> wrote:

> From: Peter Korsgaard <jacmet@uclibc.org>
> Subject: Re: devmem2
> To: "David Anders" <dave123_aml@yahoo.com>
> Cc: "Xianghua Xiao" <xiaoxianghua@gmail.com>, "Bj?rn Forsman" <bjorn.forsman@gmail.com>, buildroot at busybox.net
> Date: Tuesday, April 26, 2011, 12:36 AM
> >>>>> "David" == David
> Anders <dave123_aml@yahoo.com>
> writes:
> 
>  David> devmem in busybox is worthless.
> 
>  David> it has been "modified" so many times to adhere
> to the busybox
>  David> standard that it is not longer a useful item.
> 
> What do you mean about that? Devmem2 is a very simple
> program, and the
> devmem applet seems to work exactly the same the times I've
> used it
> (except for the access-to-highest-page-issue that got fixed
> back in
> 1.16.x).
> 
> -- 
> Bye, Peter Korsgaard
> 

[Buildroot] devmem2

[Peter Korsgaard]

>>>>> "David" == David Anders <dave123_aml@yahoo.com> writes:

 David> Peter,

 David> the primary commit that makes the devmem applet unusable for
 David> most debugging is this one:

 David> commit 043246560fcd5bb7bfb2caa2db270c3c0e8e06f4
 David> Author: Denis Vlasenko <vda.linux@googlemail.com>
 David> Date:   Sun Oct 26 17:26:55 2008 +0000

 David>     devmem: make it more script-friendly; don't do any reads
 David>      and output nothing if writing was requested. -100 bytes


 David> for board bring up and general development, for which devmem is
 David> primarily used, having devmem report the value before the write
 David> is important, as well as reporting the value after the write.

Ok, but adding a little shell wrapper to do that would be simple to do.

Forcing 2 extra read actions isn't that nice, both for the
script-friendlyness, but also for registers where reads have side
effects.

-- 
Bye, Peter Korsgaard

[Buildroot] devmem2

[David Anders]

Peter,

yes we've had all this argument before and devmem in buildroot has stayed the same and everyone has continued using devmem2. basically it still boils down to the request that devmem2 not be removed from buildroot.

Dave




--- On Tue, 4/26/11, Peter Korsgaard <jacmet@uclibc.org> wrote:

> From: Peter Korsgaard <jacmet@uclibc.org>
> Subject: Re: devmem2
> To: "David Anders" <dave123_aml@yahoo.com>
> Cc: "Peter Korsgaard" <jacmet@uclibc.org>, "Xianghua Xiao" <xiaoxianghua@gmail.com>, "Bj?rn Forsman" <bjorn.forsman@gmail.com>, buildroot at busybox.net
> Date: Tuesday, April 26, 2011, 9:19 AM
> >>>>> "David" == David
> Anders <dave123_aml@yahoo.com>
> writes:
> 
>  David> Peter,
> 
>  David> the primary commit that makes the devmem applet
> unusable for
>  David> most debugging is this one:
> 
>  David> commit 043246560fcd5bb7bfb2caa2db270c3c0e8e06f4
>  David> Author: Denis Vlasenko <vda.linux@googlemail.com>
>  David> Date:???Sun Oct 26 17:26:55 2008
> +0000
> 
>  David>? ???devmem: make it more
> script-friendly; don't do any reads
>  David>? ? ? and output nothing if
> writing was requested. -100 bytes
> 
> 
>  David> for board bring up and general development, for
> which devmem is
>  David> primarily used, having devmem report the value
> before the write
>  David> is important, as well as reporting the value
> after the write.
> 
> Ok, but adding a little shell wrapper to do that would be
> simple to do.
> 
> Forcing 2 extra read actions isn't that nice, both for the
> script-friendlyness, but also for registers where reads
> have side
> effects.
> 
> -- 
> Bye, Peter Korsgaard
> 

[Buildroot] devmem2

[Peter Korsgaard]

>>>>> "Xianghua" == Xianghua Xiao <xiaoxianghua@gmail.com> writes:

 Xianghua> Please keep this package, as it's very useful for embedded product
 Xianghua> debugging, and it does not take much space at all.

You are aware that busybox has a devmem applet these days, right?

-- 
Bye, Peter Korsgaard

[Buildroot] devmem2

[Xianghua Xiao]

I forgot and in the past thought devmem2 is a newer version comparing
to busybox's devmem, plus never used the busybox version.
Will try that, thanks!

On Thu, Apr 21, 2011 at 2:23 PM, Peter Korsgaard <jacmet@uclibc.org> wrote:
>>>>>> "Xianghua" == Xianghua Xiao <xiaoxianghua@gmail.com> writes:
>
> ?Xianghua> Please keep this package, as it's very useful for embedded product
> ?Xianghua> debugging, and it does not take much space at all.
>
> You are aware that busybox has a devmem applet these days, right?
>
> --
> Bye, Peter Korsgaard
>

[Buildroot] devmem2

[Ken McGuire]

I use devmem/devmem2 on a daily basis.


On Tue, 2011-04-26 at 07:40 -0700, David Anders wrote:
> Peter,
> 
> yes we've had all this argument before and devmem in buildroot has
stayed the same and everyone has continued using devmem2. basically it
still boils down to the request that devmem2 not be removed from
buildroot.
> 
> Dave
> 
> 
> 

I was thrilled when this applet was added to Busybox (which I've been
using since 2002).
The last version of Busybox I use (for omap4) is 1.17.4 and its'
devmem.c applet was 93 lines including comments and 10 lines which were
commented out. The devmem2.c that I use every day is 79 lines including
comments. Having it as a busybox applet is a nice feature.
 
Unfortunately since the referenced changes, busybox's devmem is more
difficult to use, not impossible, just a pita because it is different
form devmem2 which I use on non busybox/uClibc/buildroot based systems
(the final software configuration). Now, I compile devmem2 outside of
Bulildroot, it just takes a few seconds and I have a little script to do
it when I change uclibc/libc versions or machine architectures.

Busybox, Buildroot and uClibc are great tools and I think that Buildroot
evolving into a mini-distro is not as really a "bad thing(tm)" as some
seem to think. Keep up the good work. 

That's my opinion, maybe the right thing to do is just remove devmem
from busybox, even devmem2 from the Buildroot "distro". I can live with
building it myself. 


   ...ken... aka cynfab aka GPSFan aka WA2VFN aka NGMB...




> 
> --- On Tue, 4/26/11, Peter Korsgaard <jacmet@uclibc.org> wrote:
> 
> > From: Peter Korsgaard <jacmet@uclibc.org>
> > Subject: Re: devmem2
> > To: "David Anders" <dave123_aml@yahoo.com>
> > Cc: "Peter Korsgaard" <jacmet@uclibc.org>, "Xianghua Xiao"
<xiaoxianghua@gmail.com>, "Bj?rn Forsman" <bjorn.forsman@gmail.com>,
buildroot at busybox.net
> > Date: Tuesday, April 26, 2011, 9:19 AM
> > >>>>> "David" == David
> > Anders <dave123_aml@yahoo.com>
> > writes:
> > 
> >  David> Peter,
> > 
> >  David> the primary commit that makes the devmem applet
> > unusable for
> >  David> most debugging is this one:
> > 
> >  David> commit 043246560fcd5bb7bfb2caa2db270c3c0e8e06f4
> >  David> Author: Denis Vlasenko <vda.linux@googlemail.com>
> >  David> Date:   Sun Oct 26 17:26:55 2008
> > +0000
> > 
> >  David>     devmem: make it more
> > script-friendly; don't do any reads
> >  David>      and output nothing if
> > writing was requested. -100 bytes
> > 
> > 
> >  David> for board bring up and general development, for
> > which devmem is
> >  David> primarily used, having devmem report the value
> > before the write
> >  David> is important, as well as reporting the value
> > after the write.
> > 
> > Ok, but adding a little shell wrapper to do that would be
> > simple to do.
> > 
> > Forcing 2 extra read actions isn't that nice, both for the
> > script-friendlyness, but also for registers where reads
> > have side
> > effects.
> > 
> > -- 
> > Bye, Peter Korsgaard
> > 
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot
> 

[Buildroot] devmem2

[David Anders]

Peter,

--- On Tue, 4/26/11, Ken McGuire <kenm@desertweyr.com> wrote:

> From: Ken McGuire <kenm@desertweyr.com>
> Subject: Re: [Buildroot] devmem2
> To: buildroot at busybox.net
> Date: Tuesday, April 26, 2011, 8:51 PM
> I use devmem/devmem2 on a daily
> basis.
> 

> That's my opinion, maybe the right thing to do is just
> remove devmem
> from busybox, even devmem2 from the Buildroot "distro". I
> can live with
> building it myself. 
> 
> 

i agree, just remove the devmem applet from busybox and the devmem2 from buildroot.

problem solved.

Dave

[Buildroot] devmem2

[Xianghua Xiao]

why not keep devmem2 as an option but disable it by default, it's tiny
anyway and essential for embedded devel.

or maybe one day buildroot can 'opkg install devmem2' at devel/bringup
time and remove it when things are done.

Xianghua

On Tue, Apr 26, 2011 at 9:15 PM, David Anders <dave123_aml@yahoo.com> wrote:
> Peter,
>
> --- On Tue, 4/26/11, Ken McGuire <kenm@desertweyr.com> wrote:
>
>> From: Ken McGuire <kenm@desertweyr.com>
>> Subject: Re: [Buildroot] devmem2
>> To: buildroot at busybox.net
>> Date: Tuesday, April 26, 2011, 8:51 PM
>> I use devmem/devmem2 on a daily
>> basis.
>>
>
>> That's my opinion, maybe the right thing to do is just
>> remove devmem
>> from busybox, even devmem2 from the Buildroot "distro". I
>> can live with
>> building it myself.
>>
>>
>
> i agree, just remove the devmem applet from busybox and the devmem2 from buildroot.
>
> problem solved.
>
> Dave
>
>
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot
>

[Buildroot] devmem2

[Peter Korsgaard]

>>>>> "Xianghua" == Xianghua Xiao <xiaoxianghua@gmail.com> writes:

 Xianghua> why not keep devmem2 as an option but disable it by default,
 Xianghua> it's tiny anyway and essential for embedded devel.

That's how it is today - Busybox devmem applet is enabled in the default
busybox config, and we have a devmem2 package that is only visible when
you enable BR2_DEPRECATED.

-- 
Bye, Peter Korsgaard

[Buildroot] devmem2

[Xianghua Xiao]

I think it's the BR2_DEPRECATED flag that caused me sending out the
first email, as I somehow think it should be kept and not to be
deprecated, it's handy, useful and small.

Xianghua

On Wed, Apr 27, 2011 at 12:28 AM, Peter Korsgaard <jacmet@uclibc.org> wrote:
>>>>>> "Xianghua" == Xianghua Xiao <xiaoxianghua@gmail.com> writes:
>
> ?Xianghua> why not keep devmem2 as an option but disable it by default,
> ?Xianghua> it's tiny anyway and essential for embedded devel.
>
> That's how it is today - Busybox devmem applet is enabled in the default
> busybox config, and we have a devmem2 package that is only visible when
> you enable BR2_DEPRECATED.
>
> --
> Bye, Peter Korsgaard
>

[Buildroot] devmem2

[Peter Korsgaard]

>>>>> "David" == David Anders <dave123_aml@yahoo.com> writes:

Hi,

 David> i agree, just remove the devmem applet from busybox and the
 David> devmem2 from buildroot.

Why? From all this discussion it seems like people are using it (myself
included),

-- 
Bye, Peter Korsgaard

[Buildroot] devmem2

[Peter Korsgaard]

>>>>> "Ken" == Ken McGuire <kenm@desertweyr.com> writes:
 
 Ken> Unfortunately since the referenced changes, busybox's devmem is more
 Ken> difficult to use, not impossible, just a pita because it is different
 Ken> form devmem2 which I use on non busybox/uClibc/buildroot based systems
 Ken> (the final software configuration). Now, I compile devmem2 outside of
 Ken> Bulildroot, it just takes a few seconds and I have a little script to do
 Ken> it when I change uclibc/libc versions or machine architectures.

But we still have devmem2 in buildroot, just enable BR2_DEPRECATED
(Build options -> Show packages that are deprecated or obsolete).

-- 
Bye, Peter Korsgaard