[coreboot] Time for a new project

Jordan Crouse jordan.crouse at amd.com
Sun Apr 13 00:48:36 CEST 2008

On 12/04/08 17:06 +0200, Carl-Daniel Hailfinger wrote:
> >> SELF is missing a per-section compression algorithm specifier
> >>     
> >
> > Does it need one? Either the entire SELF is compressed, or not.
> >   
> Uh, no. The SELF design says that only some SELF segments may be
> compressed, others must not be compressed.
> > Again, LAR does the work. No?
> >   
> See above. I wouldn't have complained that much if you were right.

I'm going to address this, since it seems to be Carl-Daniel's main
sticking point.

One of the minor details of a "chooser" menu is that we need
to populate the menu with sane and descriptive names.  We could just
use the LAR "filename", but that is not very customer friendly.  
Thats where the NAME segment comes from.   I think thats pretty clear
to everybody.

I expect that when bayou first comes up in chooser mode, the 
first thing it is going to do is walk the LAR and locate all the payloads
for its menu.  While its doing that, its going to also read the names
for each of the payloads.  Forcing the entire SELF to decompress 
for this simple act costs memory and is needlessly slow.  Compressing
just the segment is silly (we're talking at most 15 to 20 bytes here),
and it forces any payloads that want to examine the SELF files in the
LAR to carry a de-compression alogrithm.  I also extended the same
behavior to the .notes section, because I deemed that the payload may
wish to store configuration information there, which would be silly
to copy to memory if we didn't need to.

The data and code segments will be compressed with the LAR compression
mechanism, if it happens to be specified (I will go back and correct
the wiki page to make that clearer).  Yes, that does mean lzma headers
per segment.  I'm okay with that, I think its worth the cost.


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