[OpenBIOS] [PATCH] make select-dev and unselect-dev compatible with OBP

[Bob Breuer]

Mark Cave-Ayland wrote:
> On 02/08/11 16:00, Bob Breuer wrote:
> 
>> select-dev and unselect-dev are pre Open Firmware, and not the same
>> as open-dev/device-end.  Make them Sun OBP compatible by pulling the
>> functionality for select-dev/unselect-dev out of (and simplifying)
>> begin-package/end-package.
>>
>> Signed-off-by: Bob Breuer<breuerr at mc.net>
>> ---
>>   forth/admin/devices.fs   |    4 ----
>>   forth/debugging/fcode.fs |   22 +++++++++++++++++-----
>>   forth/device/pathres.fs  |    4 ----
>>   3 files changed, 17 insertions(+), 13 deletions(-)
>>
>> Index: forth/device/pathres.fs
>> ===================================================================
>> --- forth/device/pathres.fs    (revision 1045)
>> +++ forth/device/pathres.fs    (working copy)
>> @@ -471,10 +471,6 @@
>>     ( ihandle )
>>   ;
>>
>> -: select-dev ( dev-str dev-len -- ihandle | 0 )
>> -  open-dev
>> -;
>> -
>>   : execute-device-method
>>   ( ... dev-str dev-len met-str met-len -- ... false | ?? true )
>>     2swap
>> Index: forth/admin/devices.fs
>> ===================================================================
>> --- forth/admin/devices.fs    (revision 1045)
>> +++ forth/admin/devices.fs    (working copy)
>> @@ -46,10 +46,6 @@
>>     0 active-package!
>>     ;
>>
>> -: unselect-dev ( -- )
>> -  device-end
>> -;
>> -
>>   : ?active-package ( -- phandle )
>>     active-package dup 0= abort" no active device"
>>   ;
>> Index: forth/debugging/fcode.fs
>> ===================================================================
>> --- forth/debugging/fcode.fs    (revision 1045)
>> +++ forth/debugging/fcode.fs    (working copy)
>> @@ -10,21 +10,33 @@
>>   : headers    ( -- )
>>     ;
>>
>> -: begin-package ( arg-str arg-len reg-str reg-len dev-str dev-len -- )
>> +\ Open specified device node and make it the current instance.
>> +\   pre Open Firmware, but Sun OBP compatible
>> +: select-dev    ( dev-str dev-len -- )
>>     open-dev dup 0= abort" failed opening parent."
>>     dup to my-self
>>     ihandle>phandle active-package!
>> +;
>> +
>> +: begin-package ( arg-str arg-len reg-str reg-len dev-str dev-len -- )
>> +  select-dev
>>     new-device
>>     set-args
>>   ;
>>
>> -: end-package    ( -- )
>> -  my-parent>r
>> -  finish-device
>> +\ Close current node, deselect active package and current instance,
>> +\ leaving no instance selected
>> +\   pre Open Firmware, but Sun OBP compatible
>> +: unselect-dev   ( -- )
>> +  my-self close-dev
>>     0 active-package!
>>     0 to my-self
>> -  r>  close-dev
>>   ;
>>
>> +: end-package    ( -- )
>> +  finish-device
>> +  unselect-dev
>> +;
>> +
>>   : apply    ( ... "method-name<  >device-specifier<  >" -- ??? )
>>     ;
> 
> I've applied this patch locally and tested it on my various SPARC32
> images and everything seems to work fine. My only minor niggle is that
> logically I would expect all of the package words to be in
> forth/admin/devices.fs rather than forth/debugging/fcode.fs.

Both begin-package and end-package were already in
forth/debugging/fcode.fs.  This is mostly just code movement/refactoring
so I moved select-dev/unselect-dev to where most of the code already
was.  Let me know if you want it another way.  None of the words that I
changed are used anywhere within OpenBIOS itself.

> 
> However... reading the IEEE 1275 specification once again I found this
> on page 251 (Section H.8): "The following user interface command names
> have changed from their pre-Open Firmware versions, with no change in
> behavior" and select-dev/unselect-dev are listed below. Hmmm. This seems
> to disagree with the original intent of the patch. Anyone have any
> further thoughts on this?

See the errata for section H.8.  Also see the "Debugging and Testing
Fcode Programs" section of "Writing FCode 3.x Programs" at
http://download.oracle.com/docs/cd/E19253-01/806-1379-10/fctest.html#pgfId-330
which shows the simpler OBP definitions for begin-package/end-package
along with descriptions of select-dev/unselect-dev.  Maybe I should add
this extra detail to the patch description and source comments.

Bob

> 
> ATB,
> 
> Mark.
>