Re: c-r4k.c cleanup

[Ralf Baechle <ralf@linux-mips.org>]

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: