[PARISC] Make sure use of RFI conforms to PA 2.0 and 1.1 arch docs

2.6.12-rc4-pa3 : first pass at making sure use of RFI conforms to
PA 2.0 arch pages F-4 and F-5, PA 1.1 Arch page 3-19 and 3-20.

The discussion revolves around all the rules for clearing PSW Q-bit.
The hard part is meeting all the rules for "relied upon translation".

.align directive is used to guarantee the critical sequence ends more than
8 instructions (32 bytes) from the end of page.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>

1 files changed, 3 insertions, 6 deletions

diff --git a/include/asm-parisc/tlbflush.h b/include/asm-parisc/tlbflush.h
index eb27b78930e8..efbb2d8625b1 100644
--- a/include/asm-parisc/tlbflush.h
+++ b/include/asm-parisc/tlbflush.h
@@ -64,29 +64,26 @@ static inline void flush_tlb_range(struct vm_area_struct *vma,
 {
         unsigned long npages;
 
-        
         npages = ((end - (start & PAGE_MASK)) + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
-        if (npages >= 512)  /* XXX arbitrary, should be tuned */
+        if (npages >= 512)  /* 2MB of space: arbitrary, should be tuned */
                 flush_tlb_all();
         else {
 
                 mtsp(vma->vm_mm->context,1);
+                purge_tlb_start();
                 if (split_tlb) {
-                        purge_tlb_start();
                         while (npages--) {
                                 pdtlb(start);
                                 pitlb(start);
                                 start += PAGE_SIZE;
                         }
-                        purge_tlb_end();
                 } else {
-                        purge_tlb_start();
                         while (npages--) {
                                 pdtlb(start);
                                 start += PAGE_SIZE;
                         }
-                        purge_tlb_end();
                 }
+                purge_tlb_end();
         }
 }