Bug #1742

PAT support

Added by aoiko almost 4 years ago. Updated over 3 years ago.

Status:NewStart date:
Priority:LowDue date:
Assignee:-% Done:

0%

Category:-
Target version:-

Description

Here's a patch for Page Attribute Table support I ported from FreeBSD
quite a while back. I'm sending it to submit@ in case someone will get
interested and deal w/ the cpu identification part (probably integrating
the FreeBSD code for that too) so we can integrate it. It will get used
more and more in new code and will significantly help porting.

As you'll notice in pmap_init_pat()

+#ifdef notyet
+ if (cpu_vendor_id != CPU_VENDOR_INTEL ||
+ (I386_CPU_FAMILY(cpu_id) == 6 && I386_CPU_MODEL(cpu_id) >=
0xe)) {
+#else
+ if (!0) {
+#endif

so we need at least I386_CPU_{FAMILY,MODEL} (to be found in
i386/include/specialreg.h) and having the companion code would be nice
too (ISTR it was straightforward but not trivial, not sure if I remember
correctly now. Looks trivial enough :/)

I *have* tried using the PMAP in mxge(4) so I don't think you'll get any
panics ;)

Aggelos

PAT-1.patch Magnifier (12.9 KB) aoiko, 04/19/2010 05:15 PM

History

#1 Updated by robgar over 3 years ago

I will take a closer look at this when I get another DFLY box up and running.
Should be Friday. If nobody gets to it before then.

#2 Updated by aoiko over 3 years ago

Am 09/07/2010 08:22 AM, schrieb Robert Garrett (via DragonFly issue
tracker):
>
> Robert Garrett<> added the comment:
>
> I will take a closer look at this when I get another DFLY box up and running.
> Should be Friday. If nobody gets to it before then.

Mmm, this patch is a bit ancient and doesn't apply. Sascha and I rewrote
it back in April and it should work on i386 but I haven't gotten round
to the amd64 bits yet (and I doubt I will in the immediate future). You
can find the patch at

http://leaf.dragonflybsd.org/~aggelos/0001-WIP-PAT.patch

HTH,
Aggelos

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