Re: [qemu-s390x] [PATCH v3 4/8] s390-ccw: interactive boot menu for eckd dasd (menu setup)

[Thomas Huth]

On 16.01.2018 20:37, Collin L. Walling wrote:
> On 01/16/2018 01:23 PM, Thomas Huth wrote:
>> On 15.01.2018 17:44, Collin L. Walling wrote:
>>> Reads boot menu flag and timeout values from the iplb and
>>> sets the respective fields for the menu.
>>>
>>> Signed-off-by: Collin L. Walling <address@hidden>
>>> ---
>> [...]
>>> diff --git a/pc-bios/s390-ccw/iplb.h b/pc-bios/s390-ccw/iplb.h
>>> index fe909d2..da29e6e 100644
>>> --- a/pc-bios/s390-ccw/iplb.h
>>> +++ b/pc-bios/s390-ccw/iplb.h
>>> @@ -81,6 +81,9 @@ extern IplParameterBlock iplb
>>> __attribute__((__aligned__(PAGE_SIZE)));
>>>   #define S390_IPL_TYPE_CCW 0x02
>>>   #define S390_IPL_TYPE_QEMU_SCSI 0xff
>>>   +#define LOADPARM_PROMPT "PROMPT  "
>>> +#define LOADPARM_EMPTY  "........"
>> I've got a question: Is there a (public) specification document
>> available somewhere for the loadparm field?
> 
> Unfortunately there does not seems to be any kind of documentation
> regarding loadparm for
> KVM on IBM z.  Most of the information available on the IBM Knowledge
> Center focuses on
> z/VM, which isn't very helpful in this case :(

Ok, too bad :-(

> Are there any specific questions that I can help with?

I was just wondering whether there are pre-defined values for this
field, e.g. is "PROMPT" something you came up with, or is this a value
that has been documented in a specification somewhere? ... I'm just
curious: If there is a list of pre-defined values somewhere, what are
the other values that the s390-ccw bios does not support yet?

 Thomas