sync c-tx39.c with c-r4k.c

[Atsushi Nemoto <anemo@mba.ocn.ne.jp>]

tx39_flush_cache_range() do nothing if !cpu_has_dc_aliases.  It should
flush d-cache and invalidate i-cache since TX39(H2) has separate I/D
cache.

Here is a patch.  

diff -u linux-mips/arch/mips/mm/c-tx39.c linux/arch/mips/mm/c-tx39.c
--- linux-mips/arch/mips/mm/c-tx39.c    2005-09-05 10:16:59.000000000 +0900
+++ linux/arch/mips/mm/c-tx39.c 2005-09-28 18:51:43.000000000 +0900
@@ -167,15 +167,16 @@
 static void tx39_flush_cache_range(struct vm_area_struct *vma,
        unsigned long start, unsigned long end)
 {
-       struct mm_struct *mm = vma->vm_mm;
+       int exec;
 
-       if (!cpu_has_dc_aliases)
+       if (!(cpu_context(smp_processor_id(), vma->vm_mm)))
                return;
 
-       if (cpu_context(smp_processor_id(), mm) != 0) {
+       exec = vma->vm_flags & VM_EXEC;
+       if (cpu_has_dc_aliases || exec)
                tx39_blast_dcache();
+       if (exec)
                tx39_blast_icache();
-       }
 }
 
 static void tx39_flush_cache_page(struct vm_area_struct *vma, unsigned long 
page, unsigned long pfn)

---
Atsushi Nemoto