RE: [PATCH] - make qemu serial summagraphics settings a bitmore fluid

RE: [PATCH] - make qemu serial summagraphics settings a bitmore fluid

[Dugger, Donald D]

Ben-

That explains how it, you're explictly setting the serial name from the
command line.  For the case of the Summa driver I think it's redundant
to require the `-serial' flag.  Right now the driver is, by definition,
a serial device and, therefore, if you specify a Summa port you are
implicitly saying you want to reserve that serial resouce.
Note that the serial console on port 0 is also implicitly specified,
that was the model I was following.

I would prefer to see it that where you process the `-summ' flag you set
the appropriate serial device name to "nul" at the same time, I think
that's easiest for the user.

There's no need to be able to specify more than one serial port as a
Summa device, it doesn't make sense and the rest of the code isn't set
up to handle that any way.  I see it that there are only two options, no
Summa or Summa on port n.  That's why I was saying you don't need an
array, just an integer.  The integer holds -1 to indicate no Summa at
all and the serial port number otherwise.

--
Don Dugger
"Censeo Toto nos in Kansa esse decisse." - D. Gale
Donald.D.Dugger@intel.com
Ph: (303)440-1368 

>-----Original Message-----
>From: Ben Thomas [mailto:bthomas@virtualiron.com] 
>Sent: Thursday, May 18, 2006 3:30 PM
>To: Dugger, Donald D
>Cc: xen-devel@lists.xensource.com
>Subject: Re: [Xen-devel] [PATCH] - make qemu serial 
>summagraphics settings a bitmore fluid
>
>Hi Don,
>
>I have this code running in another tree, so let me try to go
>through these.  It's quite possible that qemu has outsmarted
>me in this configuration.
>
>Dugger, Donald D wrote:
>> Ben-
>> 
>> I like the idea but I don't understand how this patch can work:
>> 
>> 1)  You never put a name into `serial_devices[]' for the summa port.
>> The loop in `main' that initializes the serial devices only calls
>> `qemu_chr_open' if there's a string name in 
>`serial_devices'.  How did
>> you get this to work?
>
>I use -serial in the qemu command line.  For instance, I generally
>use something like -serial pty -serial pty -serial null -serial pty,
>which is asking for COM1, COM2 and COM4 assignments to a pty.  
>The model
>is that you ask for a serial line, and also optionally 
>indicate that you
>want it to be summagraphics.
>
>For instance, here's a command line that I just generated/used.
>It requests multiple serial lines. none of which are summagraphic.
>
>/bin/qemu-dm -d 7 -m 256 -monitor pty -serial pty -serial pty 
>-serial pty
>   -serial pty -vnc -vncconnect 10.1.2.26 -k en-us -timeoffset -1800
>   -vcpus 1 -macaddr 00:0f:4b:11:01:89 -bridge nexbr1 -hda /dev/dm-4
>   -domain-name "Fedora Core 4 - 32 Bit"
>
>> 2)  Minor point, I don't see the need for the `serial_summa' array, a
>> simple integer that is initialized to -1 would accomplish the same
>> thing.  (I have this thing about wasting memory :-)
>
>I use the array so that I know which of the COMn ports are actually
>using the Summagraphic protocols.  A bit array would work as well,
>I suppose.
>
>I chose to allow any/all/none of the ports to be running the protocol
>and not just a fixed instance or only one.
>
>> 
>> 3)  Personally, I hate counting serial ports from 1, everybody knows
>> that computers count from 0.  I'd refer to it as which `ttyS' port to
>> use, starting from 0, but I'm willing to live with the COM 
>terminology.
>
>Me, too.  I decided to follow the COM1/COM2/COM3/COM4 nomenclature as
>this felt more like the PC hardware choice rather than an OS specific
>choice.  I'd guess that Windows people won't be using ttyS, 
>for instance.
>
>How do you think we should proceed with this ?  My goal is quite
>simple: allow some set (including none) of the serial lines to be
>created and use the Summagraphics protocol (or not).
>
>Does this make sense, or have I totally misunderstood something ?
>
>
>Thanks,
>-b
>
>> --
>> Don Dugger
>> "Censeo Toto nos in Kansa esse decisse." - D. Gale
>> Donald.D.Dugger@intel.com
>> Ph: (303)440-1368 
>> 
>> 
>>>-----Original Message-----
>>>From: xen-devel-bounces@lists.xensource.com 
>>>[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of 
>Ben Thomas
>>>Sent: Thursday, May 18, 2006 12:50 PM
>>>To: xen-devel@lists.xensource.com
>>>Subject: [Xen-devel] [PATCH] - make qemu serial summagraphics 
>>>settings a bitmore fluid
>>>
>>>Changeset 9967 made the qemu serial line Summagraphics 
>support a little
>>>more flexible with respect to the COM line chosen.  This patch
>>>furthers that effort by removing the COM2 restriction.  This patch
>>>allows a "-summa n" command line option to qemu to specify which, if
>>>any, COM port should be using the Summagraphics protocols.
>>>
>>>Signed-off-by: Ben Thomas (ben@virtualiron.com)
>>>
>>>-- 
>>>---------------------------------------------------------------
>>>---------
>>>Ben Thomas                                         Virtual 
>>>Iron Software
>>>bthomas@virtualiron.com                            Tower 1, Floor 2
>>>978-849-1214                                       900 
>>>Chelmsford Street
>>>                                                   Lowell, MA 01851
>>>
>
>
>-- 
>---------------------------------------------------------------
>---------
>Ben Thomas                                         Virtual 
>Iron Software
>bthomas@virtualiron.com                            Tower 1, Floor 2
>978-849-1214                                       900 
>Chelmsford Street
>                                                    Lowell, MA 01851
>

Re: [PATCH] - make qemu serial summagraphics settings a bitmore fluid

[Ben Thomas]

Hi Don,

Thanks for the info.  I was being a bit too flexible, I guess.
Let me take a look at the code and see if there's some
reasonable method to accomplish all the goals.  What I'm
thinking of here is asking for summa support on COM4, when
in fact you haven't asked for COM2 or COM3 to exist.  I'd like
to make sure that all the bases are covered appropriately.
Perhaps that's an unreasonable example, but if it can be
specified on a command line, I've found that someone
will ask for it and I'd prefer to have it covered in advance.

And, as you note, I am explictly trying to allow the case of
4 serial lines none of which have the summa protocol on them.

I'll see if I can get something put together tomorrow.

Thanks,
-b



Dugger, Donald D wrote:
> Ben-
> 
> That explains how it, you're explictly setting the serial name from the
> command line.  For the case of the Summa driver I think it's redundant
> to require the `-serial' flag.  Right now the driver is, by definition,
> a serial device and, therefore, if you specify a Summa port you are
> implicitly saying you want to reserve that serial resouce.
> Note that the serial console on port 0 is also implicitly specified,
> that was the model I was following.
> 
> I would prefer to see it that where you process the `-summ' flag you set
> the appropriate serial device name to "nul" at the same time, I think
> that's easiest for the user.
> 
> There's no need to be able to specify more than one serial port as a
> Summa device, it doesn't make sense and the rest of the code isn't set
> up to handle that any way.  I see it that there are only two options, no
> Summa or Summa on port n.  That's why I was saying you don't need an
> array, just an integer.  The integer holds -1 to indicate no Summa at
> all and the serial port number otherwise.
> 
> --
> Don Dugger
> "Censeo Toto nos in Kansa esse decisse." - D. Gale
> Donald.D.Dugger@intel.com
> Ph: (303)440-1368 


-- 
------------------------------------------------------------------------
Ben Thomas                                         Virtual Iron Software
bthomas@virtualiron.com                            Tower 1, Floor 2
978-849-1214                                       900 Chelmsford Street
                                                    Lowell, MA 01851

RE: [PATCH] - make qemu serial summagraphics settings a bitmore fluid

[Dugger, Donald D]

Ben-

I like the idea but I don't understand how this patch can work:

1)  You never put a name into `serial_devices[]' for the summa port.
The loop in `main' that initializes the serial devices only calls
`qemu_chr_open' if there's a string name in `serial_devices'.  How did
you get this to work?

2)  Minor point, I don't see the need for the `serial_summa' array, a
simple integer that is initialized to -1 would accomplish the same
thing.  (I have this thing about wasting memory :-)

3)  Personally, I hate counting serial ports from 1, everybody knows
that computers count from 0.  I'd refer to it as which `ttyS' port to
use, starting from 0, but I'm willing to live with the COM terminology.

--
Don Dugger
"Censeo Toto nos in Kansa esse decisse." - D. Gale
Donald.D.Dugger@intel.com
Ph: (303)440-1368 

>-----Original Message-----
>From: xen-devel-bounces@lists.xensource.com 
>[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of Ben Thomas
>Sent: Thursday, May 18, 2006 12:50 PM
>To: xen-devel@lists.xensource.com
>Subject: [Xen-devel] [PATCH] - make qemu serial summagraphics 
>settings a bitmore fluid
>
>Changeset 9967 made the qemu serial line Summagraphics support a little
>more flexible with respect to the COM line chosen.  This patch
>furthers that effort by removing the COM2 restriction.  This patch
>allows a "-summa n" command line option to qemu to specify which, if
>any, COM port should be using the Summagraphics protocols.
>
>Signed-off-by: Ben Thomas (ben@virtualiron.com)
>
>-- 
>---------------------------------------------------------------
>---------
>Ben Thomas                                         Virtual 
>Iron Software
>bthomas@virtualiron.com                            Tower 1, Floor 2
>978-849-1214                                       900 
>Chelmsford Street
>                                                    Lowell, MA 01851
>

Re: [PATCH] - make qemu serial summagraphics settings a bitmore fluid

[Ben Thomas]

Hi Don,

I have this code running in another tree, so let me try to go
through these.  It's quite possible that qemu has outsmarted
me in this configuration.

Dugger, Donald D wrote:
> Ben-
> 
> I like the idea but I don't understand how this patch can work:
> 
> 1)  You never put a name into `serial_devices[]' for the summa port.
> The loop in `main' that initializes the serial devices only calls
> `qemu_chr_open' if there's a string name in `serial_devices'.  How did
> you get this to work?

I use -serial in the qemu command line.  For instance, I generally
use something like -serial pty -serial pty -serial null -serial pty,
which is asking for COM1, COM2 and COM4 assignments to a pty.  The model
is that you ask for a serial line, and also optionally indicate that you
want it to be summagraphics.

For instance, here's a command line that I just generated/used.
It requests multiple serial lines. none of which are summagraphic.

/bin/qemu-dm -d 7 -m 256 -monitor pty -serial pty -serial pty -serial pty
   -serial pty -vnc -vncconnect 10.1.2.26 -k en-us -timeoffset -1800
   -vcpus 1 -macaddr 00:0f:4b:11:01:89 -bridge nexbr1 -hda /dev/dm-4
   -domain-name "Fedora Core 4 - 32 Bit"

> 2)  Minor point, I don't see the need for the `serial_summa' array, a
> simple integer that is initialized to -1 would accomplish the same
> thing.  (I have this thing about wasting memory :-)

I use the array so that I know which of the COMn ports are actually
using the Summagraphic protocols.  A bit array would work as well,
I suppose.

I chose to allow any/all/none of the ports to be running the protocol
and not just a fixed instance or only one.

> 
> 3)  Personally, I hate counting serial ports from 1, everybody knows
> that computers count from 0.  I'd refer to it as which `ttyS' port to
> use, starting from 0, but I'm willing to live with the COM terminology.

Me, too.  I decided to follow the COM1/COM2/COM3/COM4 nomenclature as
this felt more like the PC hardware choice rather than an OS specific
choice.  I'd guess that Windows people won't be using ttyS, for instance.

How do you think we should proceed with this ?  My goal is quite
simple: allow some set (including none) of the serial lines to be
created and use the Summagraphics protocol (or not).

Does this make sense, or have I totally misunderstood something ?


Thanks,
-b

> --
> Don Dugger
> "Censeo Toto nos in Kansa esse decisse." - D. Gale
> Donald.D.Dugger@intel.com
> Ph: (303)440-1368 
> 
> 
>>-----Original Message-----
>>From: xen-devel-bounces@lists.xensource.com 
>>[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of Ben Thomas
>>Sent: Thursday, May 18, 2006 12:50 PM
>>To: xen-devel@lists.xensource.com
>>Subject: [Xen-devel] [PATCH] - make qemu serial summagraphics 
>>settings a bitmore fluid
>>
>>Changeset 9967 made the qemu serial line Summagraphics support a little
>>more flexible with respect to the COM line chosen.  This patch
>>furthers that effort by removing the COM2 restriction.  This patch
>>allows a "-summa n" command line option to qemu to specify which, if
>>any, COM port should be using the Summagraphics protocols.
>>
>>Signed-off-by: Ben Thomas (ben@virtualiron.com)
>>
>>-- 
>>---------------------------------------------------------------
>>---------
>>Ben Thomas                                         Virtual 
>>Iron Software
>>bthomas@virtualiron.com                            Tower 1, Floor 2
>>978-849-1214                                       900 
>>Chelmsford Street
>>                                                   Lowell, MA 01851
>>


-- 
------------------------------------------------------------------------
Ben Thomas                                         Virtual Iron Software
bthomas@virtualiron.com                            Tower 1, Floor 2
978-849-1214                                       900 Chelmsford Street
                                                    Lowell, MA 01851