From: timur@codeaurora.org (Timur Tabi)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH RFC] Watchdog: sbsa_gwdt: Enhance timeout range
Date: Thu, 5 May 2016 18:45:52 -0500 [thread overview]
Message-ID: <572BDB30.9060602@codeaurora.org> (raw)
In-Reply-To: <572BD959.3090507@codeaurora.org>
Timur Tabi wrote:
>
>> A 32-bit counter is absolutely fine. Letting it run with a 400MHz clock
>> (or was it 200 MHz ?) is the problem. A resolution of 2.5ns for a
>> watchdog
>> timer does not really make any sense.
>
> The 10 second limit is based on a 20MHz clock.
No, that's not true. I misread the code. I knew something was wrong,
but it didn't click until just now.
The default timeout is 10 seconds. The max timeout on a 20MHz system
(which is what we're running) is over 200 seconds.
The problem is that Pratyush's system is running at a clock that's way
too fast:
[ 131.187562] sbsa-gwdt sbsa-gwdt.0: Initialized with 40s timeout @
250000000 Hz, action=1.
250MHz is unreasonable. Pratyush, why is your system counter so high?
On our ARM64 system, it's set to 20MHz.
--
Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
Forum, a Linux Foundation collaborative project.
next prev parent reply other threads:[~2016-05-05 23:45 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-03 8:20 [PATCH RFC] Watchdog: sbsa_gwdt: Enhance timeout range Pratyush Anand
2016-05-03 12:12 ` Timur Tabi
2016-05-03 13:24 ` Pratyush Anand
2016-05-03 13:47 ` Guenter Roeck
2016-05-03 14:17 ` Pratyush Anand
2016-05-03 14:46 ` Guenter Roeck
2016-05-03 15:04 ` Timur Tabi
2016-05-03 13:29 ` Guenter Roeck
2016-05-03 14:38 ` Pratyush Anand
2016-05-03 15:07 ` Timur Tabi
2016-05-03 15:51 ` Pratyush Anand
2016-05-03 17:16 ` Guenter Roeck
2016-05-04 14:14 ` Pratyush Anand
2016-05-04 14:21 ` Timur Tabi
2016-05-04 15:59 ` Pratyush Anand
2016-05-04 16:17 ` Timur Tabi
2016-05-05 16:43 ` Guenter Roeck
2016-05-05 18:20 ` Pratyush Anand
2016-05-05 18:22 ` Timur Tabi
2016-05-05 23:36 ` Guenter Roeck
2016-05-05 23:38 ` Timur Tabi
2016-05-05 23:45 ` Timur Tabi [this message]
2016-05-06 0:18 ` Guenter Roeck
2016-05-05 23:51 ` Guenter Roeck
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