[PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Thomas Weber]

Magic SysRq key is not working for OMAP on new serial
console ttyOx because SUPPORT_SYSRQ is not defined
for omap-serial.

This patch defines SUPPORT_SYSRQ in omap-serial and
enables handling of Magic SysRq character.

Signed-off-by: Thomas Weber <weber@corscience.de>
---
Changes from v1: Changed comment

 drivers/serial/omap-serial.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/serial/omap-serial.c b/drivers/serial/omap-serial.c
index 1201eff..907be9b 100644
--- a/drivers/serial/omap-serial.c
+++ b/drivers/serial/omap-serial.c
@@ -20,6 +20,10 @@
  * this driver as required for the omap-platform.
  */
 
+#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/console.h>
-- 
1.7.4.rc2

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Govindraj]

On Wed, Jan 19, 2011 at 2:11 PM, Thomas Weber <weber@corscience.de> wrote:
> Magic SysRq key is not working for OMAP on new serial
> console ttyOx because SUPPORT_SYSRQ is not defined
> for omap-serial.
>
> This patch defines SUPPORT_SYSRQ in omap-serial and
> enables handling of Magic SysRq character.
>
> Signed-off-by: Thomas Weber <weber@corscience.de>

Looks fine to me.

Acked-by: Govindraj.R <govindraj.raja@ti.com>

> ---
> Changes from v1: Changed comment
>
>  drivers/serial/omap-serial.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/serial/omap-serial.c b/drivers/serial/omap-serial.c
> index 1201eff..907be9b 100644
> --- a/drivers/serial/omap-serial.c
> +++ b/drivers/serial/omap-serial.c
> @@ -20,6 +20,10 @@
>  * this driver as required for the omap-platform.
>  */
>
> +#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
> +#define SUPPORT_SYSRQ
> +#endif
> +
>  #include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/console.h>
> --
> 1.7.4.rc2
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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> Please read the FAQ at  http://www.tux.org/lkml/
>

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[G, Manjunath Kondaiah]

On Wed, Jan 19, 2011 at 03:01:39PM +0530, Govindraj wrote:
> On Wed, Jan 19, 2011 at 2:11 PM, Thomas Weber <weber@corscience.de> wrote:
> > Magic SysRq key is not working for OMAP on new serial
> > console ttyOx because SUPPORT_SYSRQ is not defined
> > for omap-serial.
> >
> > This patch defines SUPPORT_SYSRQ in omap-serial and
> > enables handling of Magic SysRq character.
> >
> > Signed-off-by: Thomas Weber <weber@corscience.de>
> 
> Looks fine to me.
> 
> Acked-by: Govindraj.R <govindraj.raja@ti.com>
I tried to use SysRq key on minicom after applying this patch, it looks
like it is not triggering sysrq event.

Am I missing anything?

-Manjunath

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Thomas Weber]

Am 19.01.2011 14:00, schrieb G, Manjunath Kondaiah:
> On Wed, Jan 19, 2011 at 03:01:39PM +0530, Govindraj wrote:
>> On Wed, Jan 19, 2011 at 2:11 PM, Thomas Weber <weber@corscience.de> wrote:
>>> Magic SysRq key is not working for OMAP on new serial
>>> console ttyOx because SUPPORT_SYSRQ is not defined
>>> for omap-serial.
>>>
>>> This patch defines SUPPORT_SYSRQ in omap-serial and
>>> enables handling of Magic SysRq character.
>>>
>>> Signed-off-by: Thomas Weber <weber@corscience.de>
>>
>> Looks fine to me.
>>
>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
> I tried to use SysRq key on minicom after applying this patch, it looks
> like it is not triggering sysrq event.
> 
> Am I missing anything?
> 
> -Manjunath
> --
Hello Manjunath,

Do you have CONFIG_MAGIC_SYSRQ enabled?
Magic SysRq key in Kernel Hacking

I tested it on Devkit8000 (beagle board clone).

Thomas

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Govindraj]

On Wed, Jan 19, 2011 at 7:01 PM, Thomas Weber <weber@corscience.de> wrote:
> Am 19.01.2011 14:00, schrieb G, Manjunath Kondaiah:
>> On Wed, Jan 19, 2011 at 03:01:39PM +0530, Govindraj wrote:
>>> On Wed, Jan 19, 2011 at 2:11 PM, Thomas Weber <weber@corscience.de> wrote:
>>>> Magic SysRq key is not working for OMAP on new serial
>>>> console ttyOx because SUPPORT_SYSRQ is not defined
>>>> for omap-serial.
>>>>
>>>> This patch defines SUPPORT_SYSRQ in omap-serial and
>>>> enables handling of Magic SysRq character.
>>>>
>>>> Signed-off-by: Thomas Weber <weber@corscience.de>
>>>
>>> Looks fine to me.
>>>
>>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
>> I tried to use SysRq key on minicom after applying this patch, it looks
>> like it is not triggering sysrq event.
>>
>> Am I missing anything?
>>
>> -Manjunath
>> --
> Hello Manjunath,
>
> Do you have CONFIG_MAGIC_SYSRQ enabled?
> Magic SysRq key in Kernel Hacking
>
> I tested it on Devkit8000 (beagle board clone).
>

re-setting lsr_break_flag to 0 in receive chars is causing issues
in getting sysrq key break sequence on omap-serial.c

Manju,

can you try this change on your environment.
With below change works for me on 3430SDP/4430SDP.
key sequence I checked.
[alt + b + t]  => shows trace of tasks running.
[alt + b + b] => system reboot.


diff --git a/drivers/serial/omap-serial.c b/drivers/serial/omap-serial.c
index 1201eff..6df623e 100644
--- a/drivers/serial/omap-serial.c
+++ b/drivers/serial/omap-serial.c
@@ -20,6 +20,10 @@
  * this driver as required for the omap-platform.
  */

+#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/console.h>
@@ -190,7 +194,6 @@ static inline void receive_chars(struct
uart_omap_port *up, int *status)
                        if (up->port.line == up->port.cons->index) {
                                /* Recover the break flag from console xmit */
                                lsr |= up->lsr_break_flag;
-                               up->lsr_break_flag = 0;
                        }
 #endif
                        if (lsr & UART_LSR_BI)


--
Thanks,
Govindraj.R

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Thomas Weber]

Am 19.01.2011 14:58, schrieb Govindraj:
> On Wed, Jan 19, 2011 at 7:01 PM, Thomas Weber <weber@corscience.de> wrote:
>> Am 19.01.2011 14:00, schrieb G, Manjunath Kondaiah:
>>> On Wed, Jan 19, 2011 at 03:01:39PM +0530, Govindraj wrote:
>>>> On Wed, Jan 19, 2011 at 2:11 PM, Thomas Weber <weber@corscience.de> wrote:
>>>>> Magic SysRq key is not working for OMAP on new serial
>>>>> console ttyOx because SUPPORT_SYSRQ is not defined
>>>>> for omap-serial.
>>>>>
>>>>> This patch defines SUPPORT_SYSRQ in omap-serial and
>>>>> enables handling of Magic SysRq character.
>>>>>
>>>>> Signed-off-by: Thomas Weber <weber@corscience.de>
>>>>
>>>> Looks fine to me.
>>>>
>>>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
>>> I tried to use SysRq key on minicom after applying this patch, it looks
>>> like it is not triggering sysrq event.
>>>
>>> Am I missing anything?
>>>
>>> -Manjunath
>>> --
>> Hello Manjunath,
>>
>> Do you have CONFIG_MAGIC_SYSRQ enabled?
>> Magic SysRq key in Kernel Hacking
>>
>> I tested it on Devkit8000 (beagle board clone).
>>
> 
> re-setting lsr_break_flag to 0 in receive chars is causing issues
> in getting sysrq key break sequence on omap-serial.c
> 
> Manju,
> 
> can you try this change on your environment.
> With below change works for me on 3430SDP/4430SDP.
> key sequence I checked.
> [alt + b + t]  => shows trace of tasks running.
> [alt + b + b] => system reboot.
> 
> 
> diff --git a/drivers/serial/omap-serial.c b/drivers/serial/omap-serial.c
> index 1201eff..6df623e 100644
> --- a/drivers/serial/omap-serial.c
> +++ b/drivers/serial/omap-serial.c
> @@ -20,6 +20,10 @@
>   * this driver as required for the omap-platform.
>   */
> 
> +#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
> +#define SUPPORT_SYSRQ
> +#endif
> +
>  #include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/console.h>
> @@ -190,7 +194,6 @@ static inline void receive_chars(struct
> uart_omap_port *up, int *status)
>                         if (up->port.line == up->port.cons->index) {
>                                 /* Recover the break flag from console xmit */
>                                 lsr |= up->lsr_break_flag;
> -                               up->lsr_break_flag = 0;
>                         }
>  #endif
>                         if (lsr & UART_LSR_BI)
> 
> 
> --
> Thanks,
> Govindraj.R
> --

Hello,

both version works for me.

Thomas

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[G, Manjunath Kondaiah]

On Wed, Jan 19, 2011 at 07:28:20PM +0530, Govindraj wrote:
> On Wed, Jan 19, 2011 at 7:01 PM, Thomas Weber <weber@corscience.de> wrote:
> > Am 19.01.2011 14:00, schrieb G, Manjunath Kondaiah:
> >> On Wed, Jan 19, 2011 at 03:01:39PM +0530, Govindraj wrote:
> >>> On Wed, Jan 19, 2011 at 2:11 PM, Thomas Weber <weber@corscience.de> wrote:
> >>>> Magic SysRq key is not working for OMAP on new serial
> >>>> console ttyOx because SUPPORT_SYSRQ is not defined
> >>>> for omap-serial.
> >>>>
> >>>> This patch defines SUPPORT_SYSRQ in omap-serial and
> >>>> enables handling of Magic SysRq character.
> >>>>
> >>>> Signed-off-by: Thomas Weber <weber@corscience.de>
> >>>
> >>> Looks fine to me.
> >>>
> >>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
> >> I tried to use SysRq key on minicom after applying this patch, it looks
> >> like it is not triggering sysrq event.
> >>
> >> Am I missing anything?
> >>
> >> -Manjunath
> >> --
> > Hello Manjunath,
> >
> > Do you have CONFIG_MAGIC_SYSRQ enabled?
> > Magic SysRq key in Kernel Hacking
> >
> > I tested it on Devkit8000 (beagle board clone).
> >
> 
> re-setting lsr_break_flag to 0 in receive chars is causing issues
> in getting sysrq key break sequence on omap-serial.c
> 
> Manju,
> 
> can you try this change on your environment.
> With below change works for me on 3430SDP/4430SDP.
> key sequence I checked.
> [alt + b + t]  => shows trace of tasks running.
> [alt + b + b] => system reboot.

With below patch, it works fine on TeraTerm. However, I am not able to
perform the same on minicom.

Tested-by: Manjunath G Kondaiah <manjugk@ti.com>

-Manjunath

> 
> 
> diff --git a/drivers/serial/omap-serial.c b/drivers/serial/omap-serial.c
> index 1201eff..6df623e 100644
> --- a/drivers/serial/omap-serial.c
> +++ b/drivers/serial/omap-serial.c
> @@ -20,6 +20,10 @@
>   * this driver as required for the omap-platform.
>   */
> 
> +#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
> +#define SUPPORT_SYSRQ
> +#endif
> +
>  #include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/console.h>
> @@ -190,7 +194,6 @@ static inline void receive_chars(struct
> uart_omap_port *up, int *status)
>                         if (up->port.line == up->port.cons->index) {
>                                 /* Recover the break flag from console xmit */
>                                 lsr |= up->lsr_break_flag;
> -                               up->lsr_break_flag = 0;
>                         }
>  #endif
>                         if (lsr & UART_LSR_BI)
> 
> 
> --
> Thanks,
> Govindraj.R

RE: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Anand Gadiyar]

> > >>>> Magic SysRq key is not working for OMAP on new serial
> > >>>> console ttyOx because SUPPORT_SYSRQ is not defined
> > >>>> for omap-serial.
> > >>>>
> > >>>> This patch defines SUPPORT_SYSRQ in omap-serial and
> > >>>> enables handling of Magic SysRq character.
> > >>>>
> > >>>> Signed-off-by: Thomas Weber <weber@corscience.de>
> > >>>
> > >>> Looks fine to me.
> > >>>
> > >>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
> > >> I tried to use SysRq key on minicom after applying this patch, it
looks
> > >> like it is not triggering sysrq event.
> > >>
> > >> Am I missing anything?
> > >>
> > >> -Manjunath
> > >> --
> > > Hello Manjunath,
> > >
> > > Do you have CONFIG_MAGIC_SYSRQ enabled?
> > > Magic SysRq key in Kernel Hacking
> > >
> > > I tested it on Devkit8000 (beagle board clone).
> > >
> >
> > re-setting lsr_break_flag to 0 in receive chars is causing issues
> > in getting sysrq key break sequence on omap-serial.c
> >
> > Manju,
> >
> > can you try this change on your environment.
> > With below change works for me on 3430SDP/4430SDP.
> > key sequence I checked.
> > [alt + b + t]  => shows trace of tasks running.
> > [alt + b + b] => system reboot.
>
> With below patch, it works fine on TeraTerm. However, I am not able to
> perform the same on minicom.
>
> Tested-by: Manjunath G Kondaiah <manjugk@ti.com>
>
> -Manjunath
>

Not sure what you guys are trying out, but I am able to use sysrq
just fine in minicom (using only Thomas' original patch) - you need
to send a break sequence, and the way to do this in minicom is to
do Ctrl-A followed by F.

Works for me, without the "resetting lsr_break_flag to 0" part.

@Govind,

What are the issues you see in getting sysrq key break sequence
without your change? And how is your change fixing this?


- Anand

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Govindraj]

On Thu, Jan 20, 2011 at 5:49 PM, Anand Gadiyar <gadiyar@ti.com> wrote:
>> > >>>> Magic SysRq key is not working for OMAP on new serial
>> > >>>> console ttyOx because SUPPORT_SYSRQ is not defined
>> > >>>> for omap-serial.
>> > >>>>
>> > >>>> This patch defines SUPPORT_SYSRQ in omap-serial and
>> > >>>> enables handling of Magic SysRq character.
>> > >>>>
>> > >>>> Signed-off-by: Thomas Weber <weber@corscience.de>
>> > >>>
>> > >>> Looks fine to me.
>> > >>>
>> > >>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
>> > >> I tried to use SysRq key on minicom after applying this patch, it
> looks
>> > >> like it is not triggering sysrq event.
>> > >>
>> > >> Am I missing anything?
>> > >>
>> > >> -Manjunath
>> > >> --
>> > > Hello Manjunath,
>> > >
>> > > Do you have CONFIG_MAGIC_SYSRQ enabled?
>> > > Magic SysRq key in Kernel Hacking
>> > >
>> > > I tested it on Devkit8000 (beagle board clone).
>> > >
>> >
>> > re-setting lsr_break_flag to 0 in receive chars is causing issues
>> > in getting sysrq key break sequence on omap-serial.c
>> >
>> > Manju,
>> >
>> > can you try this change on your environment.
>> > With below change works for me on 3430SDP/4430SDP.
>> > key sequence I checked.
>> > [alt + b + t]  => shows trace of tasks running.
>> > [alt + b + b] => system reboot.
>>
>> With below patch, it works fine on TeraTerm. However, I am not able to
>> perform the same on minicom.
>>
>> Tested-by: Manjunath G Kondaiah <manjugk@ti.com>
>>
>> -Manjunath
>>
>
> Not sure what you guys are trying out, but I am able to use sysrq
> just fine in minicom (using only Thomas' original patch) - you need
> to send a break sequence, and the way to do this in minicom is to
> do Ctrl-A followed by F.
>
> Works for me, without the "resetting lsr_break_flag to 0" part.
>
> @Govind,
>
> What are the issues you see in getting sysrq key break sequence
> without your change? And how is your change fixing this?

Actually I was using teraterm on windows platform.
using keyboard to send a break char [alt + b] sometimes
i observed that first break char was getting lost and subsequent break
chars where getting
recognized. However using send break option from terterm menu seems to
work most of times.
my change can be dropped.

--
Thanks,
Govindraj.R

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[G, Manjunath Kondaiah]

On Fri, Jan 21, 2011 at 12:54:29PM +0530, Govindraj wrote:
> On Thu, Jan 20, 2011 at 5:49 PM, Anand Gadiyar <gadiyar@ti.com> wrote:
> >> > >>>> Magic SysRq key is not working for OMAP on new serial
> >> > >>>> console ttyOx because SUPPORT_SYSRQ is not defined
> >> > >>>> for omap-serial.
> >> > >>>>
> >> > >>>> This patch defines SUPPORT_SYSRQ in omap-serial and
> >> > >>>> enables handling of Magic SysRq character.
> >> > >>>>
> >> > >>>> Signed-off-by: Thomas Weber <weber@corscience.de>
> >> > >>>
> >> > >>> Looks fine to me.
> >> > >>>
> >> > >>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
> >> > >> I tried to use SysRq key on minicom after applying this patch, it
> > looks
> >> > >> like it is not triggering sysrq event.
> >> > >>
> >> > >> Am I missing anything?
> >> > >>
> >> > >> -Manjunath
> >> > >> --
> >> > > Hello Manjunath,
> >> > >
> >> > > Do you have CONFIG_MAGIC_SYSRQ enabled?
> >> > > Magic SysRq key in Kernel Hacking
> >> > >
> >> > > I tested it on Devkit8000 (beagle board clone).
> >> > >
> >> >
> >> > re-setting lsr_break_flag to 0 in receive chars is causing issues
> >> > in getting sysrq key break sequence on omap-serial.c
> >> >
> >> > Manju,
> >> >
> >> > can you try this change on your environment.
> >> > With below change works for me on 3430SDP/4430SDP.
> >> > key sequence I checked.
> >> > [alt + b + t]  => shows trace of tasks running.
> >> > [alt + b + b] => system reboot.
> >>
> >> With below patch, it works fine on TeraTerm. However, I am not able to
> >> perform the same on minicom.
> >>
> >> Tested-by: Manjunath G Kondaiah <manjugk@ti.com>
> >>
> >> -Manjunath
> >>
> >
> > Not sure what you guys are trying out, but I am able to use sysrq
> > just fine in minicom (using only Thomas' original patch) - you need
> > to send a break sequence, and the way to do this in minicom is to
> > do Ctrl-A followed by F.
> >
> > Works for me, without the "resetting lsr_break_flag to 0" part.
> >
> > @Govind,
> >
> > What are the issues you see in getting sysrq key break sequence
> > without your change? And how is your change fixing this?
> 
> Actually I was using teraterm on windows platform.
> using keyboard to send a break char [alt + b] sometimes
> i observed that first break char was getting lost and subsequent break
> chars where getting
> recognized. However using send break option from terterm menu seems to
> work most of times.
> my change can be dropped.
If it is fixing the issue of losing first break character, what is wrong in
having this patch?

Do you see any other issues because of this change?

-Manjunath

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Govindraj]

On Fri, Jan 21, 2011 at 1:15 PM, G, Manjunath Kondaiah <manjugk@ti.com> wrote:
> On Fri, Jan 21, 2011 at 12:54:29PM +0530, Govindraj wrote:
>> On Thu, Jan 20, 2011 at 5:49 PM, Anand Gadiyar <gadiyar@ti.com> wrote:
>> >> > >>>> Magic SysRq key is not working for OMAP on new serial
>> >> > >>>> console ttyOx because SUPPORT_SYSRQ is not defined
>> >> > >>>> for omap-serial.
>> >> > >>>>
>> >> > >>>> This patch defines SUPPORT_SYSRQ in omap-serial and
>> >> > >>>> enables handling of Magic SysRq character.
>> >> > >>>>
>> >> > >>>> Signed-off-by: Thomas Weber <weber@corscience.de>
>> >> > >>>
>> >> > >>> Looks fine to me.
>> >> > >>>
>> >> > >>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
>> >> > >> I tried to use SysRq key on minicom after applying this patch, it
>> > looks
>> >> > >> like it is not triggering sysrq event.
>> >> > >>
>> >> > >> Am I missing anything?
>> >> > >>
>> >> > >> -Manjunath
>> >> > >> --
>> >> > > Hello Manjunath,
>> >> > >
>> >> > > Do you have CONFIG_MAGIC_SYSRQ enabled?
>> >> > > Magic SysRq key in Kernel Hacking
>> >> > >
>> >> > > I tested it on Devkit8000 (beagle board clone).
>> >> > >
>> >> >
>> >> > re-setting lsr_break_flag to 0 in receive chars is causing issues
>> >> > in getting sysrq key break sequence on omap-serial.c
>> >> >
>> >> > Manju,
>> >> >
>> >> > can you try this change on your environment.
>> >> > With below change works for me on 3430SDP/4430SDP.
>> >> > key sequence I checked.
>> >> > [alt + b + t]  => shows trace of tasks running.
>> >> > [alt + b + b] => system reboot.
>> >>
>> >> With below patch, it works fine on TeraTerm. However, I am not able to
>> >> perform the same on minicom.
>> >>
>> >> Tested-by: Manjunath G Kondaiah <manjugk@ti.com>
>> >>
>> >> -Manjunath
>> >>
>> >
>> > Not sure what you guys are trying out, but I am able to use sysrq
>> > just fine in minicom (using only Thomas' original patch) - you need
>> > to send a break sequence, and the way to do this in minicom is to
>> > do Ctrl-A followed by F.
>> >
>> > Works for me, without the "resetting lsr_break_flag to 0" part.
>> >
>> > @Govind,
>> >
>> > What are the issues you see in getting sysrq key break sequence
>> > without your change? And how is your change fixing this?
>>
>> Actually I was using teraterm on windows platform.
>> using keyboard to send a break char [alt + b] sometimes
>> i observed that first break char was getting lost and subsequent break
>> chars where getting
>> recognized. However using send break option from terterm menu seems to
>> work most of times.
>> my change can be dropped.
> If it is fixing the issue of losing first break character, what is wrong in
> having this patch?
>
> Do you see any other issues because of this change?

Haven't seen any thing else.
Will leave it to Thomas to incorporate if he is willing to
take up the change else will post out this change some time
later.

--
Thanks,
Govindraj.R

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Kevin Hilman]

"G, Manjunath Kondaiah" <manjugk@ti.com> writes:

> On Fri, Jan 21, 2011 at 12:54:29PM +0530, Govindraj wrote:
>> On Thu, Jan 20, 2011 at 5:49 PM, Anand Gadiyar <gadiyar@ti.com> wrote:
>> >> > >>>> Magic SysRq key is not working for OMAP on new serial
>> >> > >>>> console ttyOx because SUPPORT_SYSRQ is not defined
>> >> > >>>> for omap-serial.
>> >> > >>>>
>> >> > >>>> This patch defines SUPPORT_SYSRQ in omap-serial and
>> >> > >>>> enables handling of Magic SysRq character.
>> >> > >>>>
>> >> > >>>> Signed-off-by: Thomas Weber <weber@corscience.de>
>> >> > >>>
>> >> > >>> Looks fine to me.
>> >> > >>>
>> >> > >>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
>> >> > >> I tried to use SysRq key on minicom after applying this patch, it
>> > looks
>> >> > >> like it is not triggering sysrq event.
>> >> > >>
>> >> > >> Am I missing anything?
>> >> > >>
>> >> > >> -Manjunath
>> >> > >> --
>> >> > > Hello Manjunath,
>> >> > >
>> >> > > Do you have CONFIG_MAGIC_SYSRQ enabled?
>> >> > > Magic SysRq key in Kernel Hacking
>> >> > >
>> >> > > I tested it on Devkit8000 (beagle board clone).
>> >> > >
>> >> >
>> >> > re-setting lsr_break_flag to 0 in receive chars is causing issues
>> >> > in getting sysrq key break sequence on omap-serial.c
>> >> >
>> >> > Manju,
>> >> >
>> >> > can you try this change on your environment.
>> >> > With below change works for me on 3430SDP/4430SDP.
>> >> > key sequence I checked.
>> >> > [alt + b + t]  => shows trace of tasks running.
>> >> > [alt + b + b] => system reboot.
>> >>
>> >> With below patch, it works fine on TeraTerm. However, I am not able to
>> >> perform the same on minicom.
>> >>
>> >> Tested-by: Manjunath G Kondaiah <manjugk@ti.com>
>> >>
>> >> -Manjunath
>> >>
>> >
>> > Not sure what you guys are trying out, but I am able to use sysrq
>> > just fine in minicom (using only Thomas' original patch) - you need
>> > to send a break sequence, and the way to do this in minicom is to
>> > do Ctrl-A followed by F.
>> >
>> > Works for me, without the "resetting lsr_break_flag to 0" part.
>> >
>> > @Govind,
>> >
>> > What are the issues you see in getting sysrq key break sequence
>> > without your change? And how is your change fixing this?
>> 
>> Actually I was using teraterm on windows platform.
>> using keyboard to send a break char [alt + b] sometimes
>> i observed that first break char was getting lost and subsequent break
>> chars where getting
>> recognized. However using send break option from terterm menu seems to
>> work most of times.
>> my change can be dropped.
> If it is fixing the issue of losing first break character, what is wrong in
> having this patch?
>
> Do you see any other issues because of this change?

Were you loosing the first break character because of PM?  i.e., if the
OMAP is in retention or off while idle, we will always loose the first
character.  The first character causes the wakeup, but does not make it
to the UART.

Is the first break character lost if sleep_while_idle == 0?

Kevin

Re: [PATCHv2] OMAP: Enable Magic SysRq on serial console ttyOx

[Govindraj]

On Sat, Jan 22, 2011 at 6:33 AM, Kevin Hilman <khilman@ti.com> wrote:
> "G, Manjunath Kondaiah" <manjugk@ti.com> writes:
>
>> On Fri, Jan 21, 2011 at 12:54:29PM +0530, Govindraj wrote:
>>> On Thu, Jan 20, 2011 at 5:49 PM, Anand Gadiyar <gadiyar@ti.com> wrote:
>>> >> > >>>> Magic SysRq key is not working for OMAP on new serial
>>> >> > >>>> console ttyOx because SUPPORT_SYSRQ is not defined
>>> >> > >>>> for omap-serial.
>>> >> > >>>>
>>> >> > >>>> This patch defines SUPPORT_SYSRQ in omap-serial and
>>> >> > >>>> enables handling of Magic SysRq character.
>>> >> > >>>>
>>> >> > >>>> Signed-off-by: Thomas Weber <weber@corscience.de>
>>> >> > >>>
>>> >> > >>> Looks fine to me.
>>> >> > >>>
>>> >> > >>> Acked-by: Govindraj.R <govindraj.raja@ti.com>
>>> >> > >> I tried to use SysRq key on minicom after applying this patch, it
>>> > looks
>>> >> > >> like it is not triggering sysrq event.
>>> >> > >>
>>> >> > >> Am I missing anything?
>>> >> > >>
>>> >> > >> -Manjunath
>>> >> > >> --
>>> >> > > Hello Manjunath,
>>> >> > >
>>> >> > > Do you have CONFIG_MAGIC_SYSRQ enabled?
>>> >> > > Magic SysRq key in Kernel Hacking
>>> >> > >
>>> >> > > I tested it on Devkit8000 (beagle board clone).
>>> >> > >
>>> >> >
>>> >> > re-setting lsr_break_flag to 0 in receive chars is causing issues
>>> >> > in getting sysrq key break sequence on omap-serial.c
>>> >> >
>>> >> > Manju,
>>> >> >
>>> >> > can you try this change on your environment.
>>> >> > With below change works for me on 3430SDP/4430SDP.
>>> >> > key sequence I checked.
>>> >> > [alt + b + t]  => shows trace of tasks running.
>>> >> > [alt + b + b] => system reboot.
>>> >>
>>> >> With below patch, it works fine on TeraTerm. However, I am not able to
>>> >> perform the same on minicom.
>>> >>
>>> >> Tested-by: Manjunath G Kondaiah <manjugk@ti.com>
>>> >>
>>> >> -Manjunath
>>> >>
>>> >
>>> > Not sure what you guys are trying out, but I am able to use sysrq
>>> > just fine in minicom (using only Thomas' original patch) - you need
>>> > to send a break sequence, and the way to do this in minicom is to
>>> > do Ctrl-A followed by F.
>>> >
>>> > Works for me, without the "resetting lsr_break_flag to 0" part.
>>> >
>>> > @Govind,
>>> >
>>> > What are the issues you see in getting sysrq key break sequence
>>> > without your change? And how is your change fixing this?
>>>
>>> Actually I was using teraterm on windows platform.
>>> using keyboard to send a break char [alt + b] sometimes
>>> i observed that first break char was getting lost and subsequent break
>>> chars where getting
>>> recognized. However using send break option from terterm menu seems to
>>> work most of times.
>>> my change can be dropped.
>> If it is fixing the issue of losing first break character, what is wrong in
>> having this patch?
>>
>> Do you see any other issues because of this change?
>
> Were you loosing the first break character because of PM?  i.e., if the
> OMAP is in retention or off while idle, we will always loose the first
> character.  The first character causes the wakeup, but does not make it
> to the UART.
>

No, even without PM i.e., even without setting sleep_while_idle and timeouts for
uart I observed on windows-teraterm sometimes first break char was getting lost.

--
Thanks,
Govindraj.R