- Fix SN PTC deadlock recovery

The patch that added support for a new platform chipset (shub2) broke PTC deadlock recovery on older versions of the chipset. (PTCs are the SN platform-specific method for doing a global TLB purge). This patch fixes deadlock recovery so that it works on both the old & new chipsets.

Index: linux/arch/ia64/sn/kernel/sn2/ptc_deadlock.S
=================================--- linux.orig/arch/ia64/sn/kernel/sn2/ptc_deadlock.S 2005-12-01 11:41:02.394548556 -0600
+++ linux/arch/ia64/sn/kernel/sn2/ptc_deadlock.S 2005-12-06 07:59:32.176021944 -0600
@@ -39,9 +39,13 @@ sn2_ptc_deadlock_recovery_core:
mov r8=r0

1:
+ cmp.ne p8,p9=r0,ptc1 // Test for shub type (ptc1 non-null on shub1)
+ // p8 = 1 if shub1, p9 = 1 if shub2
+
add scr2=ALIAS_OFFSET,piowc // Address of WRITE_STATUS alias register
- ;;
- ld8.acq scr1=[scr2];;
+ mov scr1=7;; // Clear DEADLOCK, WRITE_ERROR, MULTI_WRITE_ERROR
+(p8) st8.rel [scr2]=scr1;;
+(p9) ld8.acq scr1=[scr2];;

5: ld8.acq scr1=[piowc];; // Wait for PIOs to complete.
hint @pause