[Info-vax] The x86 port - was Re: VSI: "Official 8.4-1H1 Launch"

[David Froble]

JF Mezei wrote:
> With the Poulson support done, I take it focus now goes to the port to
> the 8086 ?

There is still other work to be done.  The roadmap indicates a new 
TCP/IP before the x86 port is completed.  Could be other work.

Regardless, it appears that "inquiring minds want to know ...."

So I'll make a suggestion.  While there seems to be obsticles to making 
VMS open source, I doubt there would be obsticles to an "open port". 
I'm going to assume there are document(s) that define the work to be 
done.  Perhaps post these documents to keep JF's (and others) minds 
occupied.  I'm thinking it might be interesting, and educational, to see 
the details of such a project.

> Considering x86 hardware is widely available, will this cause a
> different approach to the early porting stages porting compared to IA64
> and Alpha that started off on emulators ?
> 
> Or do emulators provide additional debugging tools that are valuable to
> the low level engineering for early steps ?
> 
> In what language is the EFI boot programme written ? (in the EFI
> "partition" in the ODS disk)
> 
> Is the EFI source code used for IA64 easily recyclable by compiling it
> using x86 as target ? Or does it require major changes ?
> 
> What about the first file in [SYSEXE] that is loaded (forget exact
> name), are the early parts written in x86 assembler ? Macro ?

> Considering that the early stage interfaces with EFI, would that portion
> also make it easy to port by just recompiling it with x86 as target ?
> 
> Would it be correct to state that the architecture differences really
> start to matter after VMS has obtained from EFI the system configuration
> and starts to load its own drivers ?
> 
> When a machine boots, how much is written in native assembler, how much
> in Macro ? and at what point do higher level languages such as C become
> usable ? (aka: at what boot message does VMS switch from native
> assembler to macro and at what boot message do higher level language
> code kick in ?

Consider JF, once you compile and link code, it's usable on the target 
platform, regardless of it's source.

What do you think Clair, an "open port" ??