* [U-Boot] break command.
@ 2013-02-14 20:19 Sean Omalley
2013-02-15 12:38 ` Albert ARIBAUD
0 siblings, 1 reply; 6+ messages in thread
From: Sean Omalley @ 2013-02-14 20:19 UTC (permalink / raw)
To: u-boot
Is there anyway to break back into u-boot after trying to boot from linux (arm)? Similar to Open Firmwares stop-a, ctrl-break? I didn't see anything in the documentation nor poking around online. I am really hoping I missed something, or there is support that just needs to be compiled in. :)
Even if it resets the cpu, or sends a signal to the jtag_reset would be fine. When the machine locks up, I don't want to have to push a button or unplug it since most of the time, I am not in the same vicinity as the machine. Leaving a serial console attached and remoting into another machine is easier and cheaper, then other alternatives. I could send a signal from a gpio to the jtag_reset (or short it), but the machine I would -want- to use doesn't have a gpio, and I don't want to spend money for multiple jtags when it seems more logical to do it through the serial console.?
Thanks!
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] break command.
2013-02-14 20:19 [U-Boot] break command Sean Omalley
@ 2013-02-15 12:38 ` Albert ARIBAUD
2013-02-15 19:00 ` Harvey Chapman
0 siblings, 1 reply; 6+ messages in thread
From: Albert ARIBAUD @ 2013-02-15 12:38 UTC (permalink / raw)
To: u-boot
Hi Sean,
(can you please set your mailer to wrap lines at about 70?75
characters? Thanks in advance!)
On Thu, 14 Feb 2013 12:19:11 -0800
(PST), Sean Omalley <omalley_s@rocketmail.com> wrote:
> Is there anyway to break back into u-boot after trying to boot from linux (arm)? Similar to Open Firmwares stop-a, ctrl-break? I didn't see anything in the documentation nor poking around online. I am really hoping I missed something, or there is support that just needs to be compiled in. :)
>
> Even if it resets the cpu, or sends a signal to the jtag_reset would be fine. When the machine locks up, I don't want to have to push a button or unplug it since most of the time, I am not in the same vicinity as the machine. Leaving a serial console attached and remoting into another machine is easier and cheaper, then other alternatives. I could send a signal from a gpio to the jtag_reset (or short it), but the machine I would -want- to use doesn't have a gpio, and I don't want to spend money for multiple jtags when it seems more logical to do it through the serial console.?
As soon as U-Boot gives control to the payload (Linux or whatever)
there is no possible assumption that U-Boot remains intact in RAM, so
your only chance is indeed some hardware reset... But then the question
is not related to U-Boot any more.
> Thanks!
No problem.
Amicalement,
--
Albert.
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] break command.
2013-02-15 12:38 ` Albert ARIBAUD
@ 2013-02-15 19:00 ` Harvey Chapman
2013-02-15 19:03 ` Peter Barada
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Harvey Chapman @ 2013-02-15 19:00 UTC (permalink / raw)
To: u-boot
On Feb 15, 2013, at 7:38 AM, Albert ARIBAUD <albert.u.boot@aribaud.net> wrote:
> On Thu, 14 Feb 2013 12:19:11 -0800
> (PST), Sean Omalley <omalley_s@rocketmail.com> wrote:
>
>> Is there anyway to break back into u-boot after trying to boot from linux (arm)? Similar to Open Firmwares stop-a, ctrl-break? I didn't see anything in the documentation nor poking around online. I am really hoping I missed something, or there is support that just needs to be compiled in. :)
>>
> As soon as U-Boot gives control to the payload (Linux or whatever)
> there is no possible assumption that U-Boot remains intact in RAM, so
> your only chance is indeed some hardware reset... But then the question
> is not related to U-Boot any more.
On that note, does anyone know of a device that would do this? Perhaps a combination device like this:
- USB interface to a pc
- serial port for device
- relay controllable A/C power plug (U.S.)
- controllable gpio (for wiring to a power button, reset switch, etc)
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] break command.
2013-02-15 19:00 ` Harvey Chapman
@ 2013-02-15 19:03 ` Peter Barada
2013-02-15 19:28 ` Ira W. Snyder
2013-02-17 20:49 ` Wolfgang Denk
2 siblings, 0 replies; 6+ messages in thread
From: Peter Barada @ 2013-02-15 19:03 UTC (permalink / raw)
To: u-boot
On 02/15/2013 02:00 PM, Harvey Chapman wrote:
> On Feb 15, 2013, at 7:38 AM, Albert ARIBAUD <albert.u.boot@aribaud.net> wrote:
>> On Thu, 14 Feb 2013 12:19:11 -0800
>> (PST), Sean Omalley <omalley_s@rocketmail.com> wrote:
>>
>>> Is there anyway to break back into u-boot after trying to boot from linux (arm)? Similar to Open Firmwares stop-a, ctrl-break? I didn't see anything in the documentation nor poking around online. I am really hoping I missed something, or there is support that just needs to be compiled in. :)
>>>
>> As soon as U-Boot gives control to the payload (Linux or whatever)
>> there is no possible assumption that U-Boot remains intact in RAM, so
>> your only chance is indeed some hardware reset... But then the question
>> is not related to U-Boot any more.
> On that note, does anyone know of a device that would do this? Perhaps a combination device like this:
>
> - USB interface to a pc
> - serial port for device
> - relay controllable A/C power plug (U.S.)
> - controllable gpio (for wiring to a power button, reset switch, etc)
>
>
If your board/processor has it, a watchdog can be used to force a reset
if it expires...
--
Peter Barada
peter.barada at logicpd.com
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] break command.
2013-02-15 19:00 ` Harvey Chapman
2013-02-15 19:03 ` Peter Barada
@ 2013-02-15 19:28 ` Ira W. Snyder
2013-02-17 20:49 ` Wolfgang Denk
2 siblings, 0 replies; 6+ messages in thread
From: Ira W. Snyder @ 2013-02-15 19:28 UTC (permalink / raw)
To: u-boot
On Fri, Feb 15, 2013 at 02:00:10PM -0500, Harvey Chapman wrote:
> On Feb 15, 2013, at 7:38 AM, Albert ARIBAUD <albert.u.boot@aribaud.net> wrote:
> > On Thu, 14 Feb 2013 12:19:11 -0800
> > (PST), Sean Omalley <omalley_s@rocketmail.com> wrote:
> >
> >> Is there anyway to break back into u-boot after trying to boot from linux (arm)? Similar to Open Firmwares stop-a, ctrl-break? I didn't see anything in the documentation nor poking around online. I am really hoping I missed something, or there is support that just needs to be compiled in. :)
> >>
> > As soon as U-Boot gives control to the payload (Linux or whatever)
> > there is no possible assumption that U-Boot remains intact in RAM, so
> > your only chance is indeed some hardware reset... But then the question
> > is not related to U-Boot any more.
>
> On that note, does anyone know of a device that would do this? Perhaps a combination device like this:
>
> - USB interface to a pc
> - serial port for device
> - relay controllable A/C power plug (U.S.)
> - controllable gpio (for wiring to a power button, reset switch, etc)
>
I have a BayTech network-attached powerstrip that does something
similar. It has switchable AC outlets and network-accessible serial
ports, but it doesn't have controllable GPIOs or a USB interface.
Ira
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] break command.
2013-02-15 19:00 ` Harvey Chapman
2013-02-15 19:03 ` Peter Barada
2013-02-15 19:28 ` Ira W. Snyder
@ 2013-02-17 20:49 ` Wolfgang Denk
2 siblings, 0 replies; 6+ messages in thread
From: Wolfgang Denk @ 2013-02-17 20:49 UTC (permalink / raw)
To: u-boot
Dear Harvey Chapman,
In message <2586B402-FB69-465C-82A4-62A065C74234@3gfp.com> you wrote:
>
> > As soon as U-Boot gives control to the payload (Linux or whatever)
> > there is no possible assumption that U-Boot remains intact in RAM, so
> > your only chance is indeed some hardware reset... But then the question
> > is not related to U-Boot any more.
>
> On that note, does anyone know of a device that would do this? Perhaps a combination device like this:
>
> - USB interface to a pc
> - serial port for device
> - relay controllable A/C power plug (U.S.)
> - controllable gpio (for wiring to a power button, reset switch, etc)
The standard approach is to use a hardware watchdog that will reset
the board if it is not triggered in time.
Best regards,
Wolfgang Denk
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
A good marriage would be between a blind wife and deaf husband.
-- Michel de Montaigne
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-02-17 20:49 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2013-02-14 20:19 [U-Boot] break command Sean Omalley
2013-02-15 12:38 ` Albert ARIBAUD
2013-02-15 19:00 ` Harvey Chapman
2013-02-15 19:03 ` Peter Barada
2013-02-15 19:28 ` Ira W. Snyder
2013-02-17 20:49 ` Wolfgang Denk
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