opal/hmi: Stop flooding HMI event for TOD errors.

Fix the issue where every thread on the chip sends HMI event to host for
TOD errors. TOD errors are reported to all the core/threads on the chip.
Any one thread can fix the error and send event. Rest of the threads don't
need to send HMI event unnecessarily.

This patch fixes this by modifying __chiptod_recover_tod_errors() function
to return -1 if no errors found. Without this change every thread that
see TFMR[51]=1 sends HMI event to the host kernel.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.ibm.com>

hw/chiptod.c

@@ -974,7 +974,7 @@ static int __chiptod_recover_tod_errors(void)
 {
 	uint64_t terr;
 	uint64_t treset = 0;
-	int i;
+	int i, rc = -1;
 	int32_t chip_id = this_cpu()->chip_id;
 
 	/* Read TOD error register */
@@ -990,6 +990,7 @@ static int __chiptod_recover_tod_errors(void)
 		(terr & TOD_ERR_DELAY_COMPL_PARITY) ||
 		(terr & TOD_ERR_TOD_REGISTER_PARITY)) {
 		chiptod_reset_tod_errors();
+		rc = 1;
 	}
 
 	/*
@@ -1023,7 +1024,9 @@ static int __chiptod_recover_tod_errors(void)
 		return 0;
 	}
 	/* We have handled all the TOD errors routed to hypervisor */
-	return 1;
+	if (treset)
+		rc = 1;
+	return rc;
 }
 
 int chiptod_recover_tod_errors(void)