EFI and binary distributors

EFI and binary distributors

[Robert Millan]

Hi there,

What is the recommended way for binary distributors of GRUB to support
PC/BIOS and EFI at the same time?  Is it possible to build a mixed binary
that supports both systems somehow? (and if it isn't, are there plans or
ongoing work for that?)

Also, which are the cpu platforms that may use EFI?  From what I could find,
it seems that:

  - ia32 doesn't have it
  - ia64 always has it
  - amd64 only has it on Intel-Macs, and will have it on more devices in
    the future

Am I missing something?

-- 
Robert Millan

My spam trap is honeypot@aybabtu.com.  Note: this address is only intended
for spam harvesters.  Writing to it will get you added to my black list.

Re: EFI and binary distributors

[Yoshinori K. Okuji]

On Tuesday 01 May 2007 22:10, Robert Millan wrote:
> What is the recommended way for binary distributors of GRUB to support
> PC/BIOS and EFI at the same time?  Is it possible to build a mixed binary
> that supports both systems somehow? (and if it isn't, are there plans or
> ongoing work for that?)

I don't think so. The size restriction is too severe for PC BIOS.

One possibility is to bundle binary images both for PC BIOS and EFI in a 
package, and selectively use one of them by grub-install. But this has a 
serious issue, on a EFI platform which supports Legacy Boot, because the user 
can use both.

Personally, I think it is much cleaner to use just EFI on EFI platforms 
instead of Legacy Boot. But this depends on a preference... For now, I have 
no good idea.

> Also, which are the cpu platforms that may use EFI?  From what I could
> find, it seems that:
>
>   - ia32 doesn't have it

You forgot about Intel Mac. :)
In fact, my Mac Mini is with Intel Core Solo, which definitely does not 
support 64-bit.

>   - ia64 always has it
>   - amd64 only has it on Intel-Macs, and will have it on more devices in
>     the future

Do Intel Mac have AMD processors, or do you mean EM64T? If you just mean IA-32 
architecture with 64-bit extensions (both Intel's and AMD's), the canonical 
name in GNU is "x86_64".

> Am I missing something?

No idea. In theory, nothing prevents porting EFI to other architectures. 
Wikipedia mentions XScale:

http://en.wikipedia.org/wiki/Extensible_Firmware_Interface

Okuji

Re: EFI and binary distributors

[Robert Millan]

On Tue, May 01, 2007 at 11:01:26PM +0200, Yoshinori K. Okuji wrote:
> On Tuesday 01 May 2007 22:10, Robert Millan wrote:
> > What is the recommended way for binary distributors of GRUB to support
> > PC/BIOS and EFI at the same time?  Is it possible to build a mixed binary
> > that supports both systems somehow? (and if it isn't, are there plans or
> > ongoing work for that?)
> 
> I don't think so. The size restriction is too severe for PC BIOS.
> 
> One possibility is to bundle binary images both for PC BIOS and EFI in a 
> package, and selectively use one of them by grub-install. But this has a 
> serious issue, on a EFI platform which supports Legacy Boot, because the user 
> can use both.
> 
> Personally, I think it is much cleaner to use just EFI on EFI platforms 
> instead of Legacy Boot. But this depends on a preference... For now, I have 
> no good idea.

Uhm sounds overcomplicated.  I think we can sort it out with two separate
binary packages for now (e.g. grub-pc and grub-efi).

> > Also, which are the cpu platforms that may use EFI?  From what I could
> > find, it seems that:
> >
> >   - ia32 doesn't have it
> 
> You forgot about Intel Mac. :)
> In fact, my Mac Mini is with Intel Core Solo, which definitely does not 
> support 64-bit.

What about powerpc?  Has EFI ever been used there?

> >   - ia64 always has it
> >   - amd64 only has it on Intel-Macs, and will have it on more devices in
> >     the future
> 
> Do Intel Mac have AMD processors, or do you mean EM64T? If you just mean IA-32 
> architecture with 64-bit extensions (both Intel's and AMD's), the canonical 
> name in GNU is "x86_64".

Yeah, I meant x86_64.  I suppose I'm too much "debian tainted" ;-)

-- 
Robert Millan

My spam trap is honeypot@aybabtu.com.  Note: this address is only intended
for spam harvesters.  Writing to it will get you added to my black list.

Re: EFI and binary distributors

[Stefan Reinauer]

* Robert Millan <rmh@aybabtu.com> [070502 15:42]:
> > >   - amd64 only has it on Intel-Macs, and will have it on more devices in
> > >     the future
> > 
> > Do Intel Mac have AMD processors, or do you mean EM64T? If you just
> > mean IA-32 architecture with 64-bit extensions (both Intel's and
> > AMD's), the canonical name in GNU is "x86_64".

Calling it IA-32 or i*86 is equally wrong when it comes down to x86
based CPUs ;-) Remember, AMD invented the AMD64 architecture, and Intel
started cloning that architecture. 

BTW: You are not supposed to call them EM64T without writing out the
full name Extended Memory 64 Technology (tm) first somewhere in the same
document. ;-)

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Re: EFI and binary distributors

[Hollis Blanchard]

On Wed, 2007-05-02 at 15:42 +0200, Robert Millan wrote:
> 
> What about powerpc?  Has EFI ever been used there? 

I've never heard of such a thing.

-Hollis

Re: EFI and binary distributors

[Marco Gerards]

Robert Millan <rmh@aybabtu.com> writes:

Hi,

> What is the recommended way for binary distributors of GRUB to support
> PC/BIOS and EFI at the same time?  Is it possible to build a mixed binary
> that supports both systems somehow? (and if it isn't, are there plans or
> ongoing work for that?)

Currently there is a i386-efi.rmk.  Perhaps this can be merged somehow
with i386-pc.rmk?  I assume this is what Robert means.  I won't object
to this, although I wonder what Okuji thinks of this.

> Also, which are the cpu platforms that may use EFI?  From what I could find,
> it seems that:
>
>   - ia32 doesn't have it

My MacBook does.

>   - ia64 always has it
>   - amd64 only has it on Intel-Macs, and will have it on more devices in
>     the future

There are some non-apple boards that does.  But usually on servers,
where one normally needs big partitions.

It's safe to assume EFI can be used anywhere or even will eventually
show up on every kind of PC system you can think of.

--
Marco