[IA64] MCA recovery: Montecito support

The information in MCA records is filled in slightly differently on
Montecito than on Madison/McKinley.  Usually, the cache check and bus
check target identifiers have the same address.   On Montecito the
cache check and bus check target identifiers can be different if 
a corrected error (ie SBE or unconsumed poison data) was encountered and
then an uncorrected error (ie DBE) was consumed.  In that case, the 
cache check target identifier is the physical address of the DBE (that
caused the MCA to surface) while the bus check target identifier is the 
physical address of the SBE.  This patch correctly finds the target
identifier that triggered the MCA.

If there are multiple valid cache target identifiers in the same
error record then use the one with the lowest cache level.

Signed-off-by: Russ Anderson (rja@sgi.com)
Signed-off-by: NTony Luck <tony.luck@intel.com>

arch/ia64/kernel/mca_drv.c

@@ -434,6 +434,50 @@ is_mca_global(peidx_table_t *peidx, pal_bus_check_info_t *pbci,
 	return MCA_IS_GLOBAL;
 }
 
+/**
+ * get_target_identifier - Get the valid Cache or Bus check target identifier.
+ * @peidx:	pointer of index of processor error section
+ *
+ * Return value:
+ *	target address on Success / 0 on Failue
+ */
+static u64
+get_target_identifier(peidx_table_t *peidx)
+{
+	u64 target_address = 0;
+	sal_log_mod_error_info_t *smei;
+	pal_cache_check_info_t *pcci;
+	int i, level = 9;
+
+	/*
+	 * Look through the cache checks for a valid target identifier
+	 * If more than one valid target identifier, return the one
+	 * with the lowest cache level.
+	 */
+	for (i = 0; i < peidx_cache_check_num(peidx); i++) {
+		smei = (sal_log_mod_error_info_t *)peidx_cache_check(peidx, i);
+		if (smei->valid.target_identifier && smei->target_identifier) {
+			pcci = (pal_cache_check_info_t *)&(smei->check_info);
+			if (!target_address || (pcci->level < level)) {
+				target_address = smei->target_identifier;
+				level = pcci->level;
+				continue;
+			}
+		}
+	}
+	if (target_address)
+		return target_address;
+
+	/*
+	 * Look at the bus check for a valid target identifier
+	 */
+	smei = peidx_bus_check(peidx, 0);
+	if (smei && smei->valid.target_identifier)
+		return smei->target_identifier;
+
+	return 0;
+}
+
 /**
  * recover_from_read_error - Try to recover the errors which type are "read"s.
  * @slidx:	pointer of index of SAL error record
@@ -450,13 +494,14 @@ recover_from_read_error(slidx_table_t *slidx,
 			peidx_table_t *peidx, pal_bus_check_info_t *pbci,
 			struct ia64_sal_os_state *sos)
 {
-	sal_log_mod_error_info_t *smei;
+	u64 target_identifier;
 	pal_min_state_area_t *pmsa;
 	struct ia64_psr *psr1, *psr2;
 	ia64_fptr_t *mca_hdlr_bh = (ia64_fptr_t*)mca_handler_bhhook;
 
 	/* Is target address valid? */
-	if (!pbci->tv)
+	target_identifier = get_target_identifier(peidx);
+	if (!target_identifier)
 		return fatal_mca("target address not valid");
 
 	/*
@@ -487,14 +532,12 @@ recover_from_read_error(slidx_table_t *slidx,
 	pmsa = sos->pal_min_state;
 	if (psr1->cpl != 0 ||
 	   ((psr2->cpl != 0) && mca_recover_range(pmsa->pmsa_iip))) {
-		smei = peidx_bus_check(peidx, 0);
-		if (smei->valid.target_identifier) {
 		/*
 		 *  setup for resume to bottom half of MCA,
 		 * "mca_handler_bhhook"
 		 */
 		/* pass to bhhook as argument (gr8, ...) */
-			pmsa->pmsa_gr[8-1] = smei->target_identifier;
+		pmsa->pmsa_gr[8-1] = target_identifier;
 		pmsa->pmsa_gr[9-1] = pmsa->pmsa_iip;
 		pmsa->pmsa_gr[10-1] = pmsa->pmsa_ipsr;
 		/* set interrupted return address (but no use) */
@@ -513,8 +556,6 @@ recover_from_read_error(slidx_table_t *slidx,
 				"kill affected process - recovered.");
 	}
 
-	}
-
 	return fatal_mca("kernel context not recovered, iip 0x%lx\n",
 			 pmsa->pmsa_iip);
 }