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From:   Conor Dooley <conor.dooley@microchip.com>
To:     Jassi Brar <jassisinghbrar@gmail.com>
CC:     Conor Dooley <conor.dooley@microchip.com>,
        Daire McNamara <daire.mcnamara@microchip.com>,
        <linux-riscv@lists.infradead.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH v2 5/7] soc: microchip: mpfs: use a consistent completion timeout
Date:   Fri, 20 Jan 2023 14:37:33 +0000
Message-ID: <20230120143734.3438755-6-conor.dooley@microchip.com>
In-Reply-To: <20230120143734.3438755-1-conor.dooley@microchip.com>
References: <20230120143734.3438755-1-conor.dooley@microchip.com>
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Completion timeouts use jiffies, so passing a number directly will
produce inconsistent timeouts depending on config. Define the timeout in
ms and convert it to jiffies instead.

Since a define is being created where one previously did not exist,
pick a suitable timeout duration. Most services will complete nearly
immediately, but those relating to image verification and re-programming
the FPGA take significant amounts of time. 30 seconds is a suitable
timeout for those situations, although most services will complete in
under 100 ms.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 drivers/soc/microchip/mpfs-sys-controller.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/microchip/mpfs-sys-controller.c b/drivers/soc/microchip/mpfs-sys-controller.c
index 12039cb38b33..e76a5e38f655 100644
--- a/drivers/soc/microchip/mpfs-sys-controller.c
+++ b/drivers/soc/microchip/mpfs-sys-controller.c
@@ -11,12 +11,19 @@
 #include <linux/slab.h>
 #include <linux/kref.h>
 #include <linux/module.h>
+#include <linux/jiffies.h>
 #include <linux/interrupt.h>
 #include <linux/of_platform.h>
 #include <linux/mailbox_client.h>
 #include <linux/platform_device.h>
 #include <soc/microchip/mpfs.h>
 
+/*
+ * This timeout must be long, as some services (example: image authentication)
+ * take many seconds to complete
+ */
+#define MPFS_SYS_CTRL_TIMEOUT_MS 30000
+
 static DEFINE_MUTEX(transaction_lock);
 
 struct mpfs_sys_controller {
@@ -28,6 +35,7 @@ struct mpfs_sys_controller {
 
 int mpfs_blocking_transaction(struct mpfs_sys_controller *sys_controller, struct mpfs_mss_msg *msg)
 {
+	unsigned long timeout = msecs_to_jiffies(MPFS_SYS_CTRL_TIMEOUT_MS);
 	int ret, err;
 
 	err = mutex_lock_interruptible(&transaction_lock);
@@ -38,7 +46,7 @@ int mpfs_blocking_transaction(struct mpfs_sys_controller *sys_controller, struct
 
 	ret = mbox_send_message(sys_controller->chan, msg);
 	if (ret >= 0) {
-		if (wait_for_completion_timeout(&sys_controller->c, HZ)) {
+		if (wait_for_completion_timeout(&sys_controller->c, timeout)) {
 			ret = 0;
 		} else {
 			ret = -ETIMEDOUT;
-- 
2.39.0