[coreboot-gerrit] Change in coreboot[master]: cpu/x86: Refactor run_ap_work() function to support no timeout

[Subrata Banik (Code Review)]

Subrata Banik has uploaded this change for review. ( https://review.coreboot.org/25622


Change subject: cpu/x86: Refactor run_ap_work() function to support no timeout
......................................................................

cpu/x86: Refactor run_ap_work() function to support no timeout

There might be certain requirement in user function where user
might not want to pass any timeout value, in those cases run_ap_work() should
consider infinity as timeout and perform all APs initialization as per specification.

BRANCH=none
BUG=b:74436746
TEST=run_ap_work() is running successfully with 0 expire_us.

Change-Id: Iacd67768c8a120f6a01baaa6817468f6b9a3b764
Signed-off-by: Subrata Banik <subrata.banik at intel.com>
---
M src/cpu/x86/mp_init.c
1 file changed, 37 insertions(+), 16 deletions(-)



  git pull ssh://review.coreboot.org:29418/coreboot refs/changes/22/25622/1

diff --git a/src/cpu/x86/mp_init.c b/src/cpu/x86/mp_init.c
index 52feca9..f1600fd 100644
--- a/src/cpu/x86/mp_init.c
+++ b/src/cpu/x86/mp_init.c
@@ -946,6 +946,24 @@
 	*(volatile mp_callback_t *)slot = value;
 }
 
+static int execute_callback_on_ap(void)
+{
+	int cpus_accepted;
+	int i;
+	int cur_cpu = cpu_index();
+
+	cpus_accepted = 0;
+
+	for (i = 0; i < ARRAY_SIZE(ap_callbacks); i++) {
+		if (cur_cpu == i)
+			continue;
+		if (read_callback(&ap_callbacks[i]) == NULL)
+			cpus_accepted++;
+	}
+
+	return cpus_accepted;
+}
+
 static int run_ap_work(mp_callback_t func, long expire_us)
 {
 	int i;
@@ -966,22 +984,25 @@
 	}
 	mfence();
 
-	/* Wait for all the APs to signal back that call has been accepted. */
-	stopwatch_init_usecs_expire(&sw, expire_us);
-	do {
-		cpus_accepted = 0;
-
-		for (i = 0; i < ARRAY_SIZE(ap_callbacks); i++) {
-			if (cur_cpu == i)
-				continue;
-			if (read_callback(&ap_callbacks[i]) == NULL)
-				cpus_accepted++;
-		}
-
-		if (cpus_accepted == global_num_aps)
-			return 0;
-	} while (!stopwatch_expired(&sw));
-
+	if (expire_us) {
+		/*
+		 * Wait for all the APs to signal back that call has been
+		 * accepted.
+		 */
+		stopwatch_init_usecs_expire(&sw, expire_us);
+		do {
+			cpus_accepted = execute_callback_on_ap();
+			if (cpus_accepted == global_num_aps)
+				return 0;
+		} while (!stopwatch_expired(&sw));
+	} else {
+		/* Wait for all the APs to signal back with no timeout */
+		do {
+			cpus_accepted = execute_callback_on_ap();
+			if (cpus_accepted == global_num_aps)
+				return 0;
+		} while (1);
+	}
 	printk(BIOS_ERR, "AP call expired. %d/%d CPUs accepted.\n",
 		cpus_accepted, global_num_aps);
 	return -1;

-- 
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Gerrit-Project: coreboot
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: Iacd67768c8a120f6a01baaa6817468f6b9a3b764
Gerrit-Change-Number: 25622
Gerrit-PatchSet: 1
Gerrit-Owner: Subrata Banik <subrata.banik at intel.com>
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