On Fri, Feb 04, 2005 at 04:45:32PM +0100, Ralf Baechle wrote:
> > Note that I-cache aliases are not completely harmless; sometimes you
> > want to invalidate any I-cache copies of some data, and if it's
> > aliased you may miss some of them. Shared libraries are generally
> > aligned to some large page-size multiple - so multiple text images are
> > usually the same colour, and don't matter. You can get problems with
> > trampolines and stuff.
>
> Linux computes the necessary alignment on the fly. The method used is
> not strictly correct because as you say it should account for possible
> I-cache aliases also.
>
> Seems it's cache day again today ;-)
This is what I've checked in.
Ralf
Index: arch/mips/mm/c-r4k.c
===================================================================
RCS file: /home/cvs/linux/arch/mips/mm/c-r4k.c,v
retrieving revision 1.97
diff -u -r1.97 c-r4k.c
--- arch/mips/mm/c-r4k.c 4 Feb 2005 15:19:01 -0000 1.97
+++ arch/mips/mm/c-r4k.c 4 Feb 2005 15:48:38 -0000
@@ -1012,9 +1012,17 @@
* normally they'd suffer from aliases but magic in the hardware deals
* with that for us so we don't need to take care ourselves.
*/
- if (c->cputype != CPU_R10000 && c->cputype != CPU_R12000)
+ switch (c->cputype) {
if (c->dcache.waysize > PAGE_SIZE)
- c->dcache.flags |= MIPS_CACHE_ALIASES;
+
+ case CPU_R10000:
+ case CPU_R12000:
+ break;
+ case CPU_24K:
+ if (!(read_c0_config7() & (1 << 16)))
+ default:
+ c->dcache.flags |= MIPS_CACHE_ALIASES;
+ }
switch (c->cputype) {
case CPU_20KC:
