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From: Nick Chan <towinchenmi@gmail.com>
To: Hector Martin <marcan@marcan.st>, Sven Peter <sven@svenpeter.dev>,
	Alyssa Rosenzweig <alyssa@rosenzweig.io>,
	Wim Van Sebroeck <wim@linux-watchdog.org>,
	Guenter Roeck <linux@roeck-us.net>,
	asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org,
	linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Nick Chan <towinchenmi@gmail.com>
Subject: [PATCH] watchdog: apple: Increase reset delay to 150ms
Date: Sat, 14 Sep 2024 01:45:05 +0800	[thread overview]
Message-ID: <20240913174540.45551-1-towinchenmi@gmail.com> (raw)

The Apple A8X SoC seems to be slowest at resetting, taking up to around
125ms to reset. Wait 150ms to be safe here.

Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
 drivers/watchdog/apple_wdt.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/watchdog/apple_wdt.c b/drivers/watchdog/apple_wdt.c
index d4f739932f0b..353ecf0b04dc 100644
--- a/drivers/watchdog/apple_wdt.c
+++ b/drivers/watchdog/apple_wdt.c
@@ -127,11 +127,11 @@ static int apple_wdt_restart(struct watchdog_device *wdd, unsigned long mode,
 	/*
 	 * Flush writes and then wait for the SoC to reset. Even though the
 	 * reset is queued almost immediately experiments have shown that it
-	 * can take up to ~20-25ms until the SoC is actually reset. Just wait
-	 * 50ms here to be safe.
+	 * can take up to ~120-125ms until the SoC is actually reset. Just
+	 * wait 150ms here to be safe.
 	 */
 	(void)readl_relaxed(wdt->regs + APPLE_WDT_WD1_CUR_TIME);
-	mdelay(50);
+	mdelay(150);
 
 	return 0;
 }

base-commit: 5acd9952f95fb4b7da6d09a3be39195a80845eb6
-- 
2.46.0


             reply	other threads:[~2024-09-13 17:46 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-09-13 17:45 Nick Chan [this message]
2024-09-13 18:01 ` [PATCH] watchdog: apple: Increase reset delay to 150ms Guenter Roeck
2024-09-13 18:02 ` Sven Peter

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