Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c
index 1ea7164..9cd70d1 100644
--- a/drivers/firmware/arm_sdei.c
+++ b/drivers/firmware/arm_sdei.c
@@ -2,6 +2,7 @@
 // Copyright (C) 2017 Arm Ltd.
 #define pr_fmt(fmt) "sdei: " fmt
 
+#include <acpi/ghes.h>
 #include <linux/acpi.h>
 #include <linux/arm_sdei.h>
 #include <linux/arm-smccc.h>
@@ -164,6 +165,7 @@
 
 	return err;
 }
+NOKPROBE_SYMBOL(invoke_sdei_fn);
 
 static struct sdei_event *sdei_event_find(u32 event_num)
 {
@@ -878,6 +880,7 @@
 {
 	arm_smccc_smc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res);
 }
+NOKPROBE_SYMBOL(sdei_smccc_smc);
 
 static void sdei_smccc_hvc(unsigned long function_id,
 			   unsigned long arg0, unsigned long arg1,
@@ -886,6 +889,74 @@
 {
 	arm_smccc_hvc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res);
 }
+NOKPROBE_SYMBOL(sdei_smccc_hvc);
+
+int sdei_register_ghes(struct ghes *ghes, sdei_event_callback *normal_cb,
+		       sdei_event_callback *critical_cb)
+{
+	int err;
+	u64 result;
+	u32 event_num;
+	sdei_event_callback *cb;
+
+	if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES))
+		return -EOPNOTSUPP;
+
+	event_num = ghes->generic->notify.vector;
+	if (event_num == 0) {
+		/*
+		 * Event 0 is reserved by the specification for
+		 * SDEI_EVENT_SIGNAL.
+		 */
+		return -EINVAL;
+	}
+
+	err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY,
+				      &result);
+	if (err)
+		return err;
+
+	if (result == SDEI_EVENT_PRIORITY_CRITICAL)
+		cb = critical_cb;
+	else
+		cb = normal_cb;
+
+	err = sdei_event_register(event_num, cb, ghes);
+	if (!err)
+		err = sdei_event_enable(event_num);
+
+	return err;
+}
+
+int sdei_unregister_ghes(struct ghes *ghes)
+{
+	int i;
+	int err;
+	u32 event_num = ghes->generic->notify.vector;
+
+	might_sleep();
+
+	if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES))
+		return -EOPNOTSUPP;
+
+	/*
+	 * The event may be running on another CPU. Disable it
+	 * to stop new events, then try to unregister a few times.
+	 */
+	err = sdei_event_disable(event_num);
+	if (err)
+		return err;
+
+	for (i = 0; i < 3; i++) {
+		err = sdei_event_unregister(event_num);
+		if (err != -EINPROGRESS)
+			break;
+
+		schedule();
+	}
+
+	return err;
+}
 
 static int sdei_get_conduit(struct platform_device *pdev)
 {
@@ -1009,7 +1080,6 @@
 
 static bool __init sdei_present_dt(void)
 {
-	struct platform_device *pdev;
 	struct device_node *np, *fw_np;
 
 	fw_np = of_find_node_by_name(NULL, "firmware");
@@ -1017,14 +1087,9 @@
 		return false;
 
 	np = of_find_matching_node(fw_np, sdei_of_match);
-	of_node_put(fw_np);
 	if (!np)
 		return false;
-
-	pdev = of_platform_device_create(np, sdei_driver.driver.name, NULL);
 	of_node_put(np);
-	if (!pdev)
-		return false;
 
 	return true;
 }