From: viresh.kumar@st•com (Viresh KUMAR)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH] Watchdog: Adding support for ARM Primecell SP805 Watchdog
Date: Tue, 27 Jul 2010 10:20:44 +0530 [thread overview]
Message-ID: <4C4E65A4.7030005@st.com> (raw)
In-Reply-To: <4C43DD7E.5050800@st.com>
On 7/19/2010 10:37 AM, vireshk wrote:
>>> +/* This routine finds load value that will reset system in required timout */
>>> >> +static void wdt_setload(unsigned int timeout)
>>> >> +{
>>> >> + u64 load, rate;
>>> >> +
>>> >> + rate = clk_get_rate(wdt->clk);
>>> >> +
>>> >> + /*
>>> >> + * sp805 runs counter with given value twice, after the end of first
>>> >> + * counter it gives an interrupt and then starts counter again. If
>>> >> + * interrupt already occured then it resets the system. This is why
>>> >> + * load is half of what should be required.
>>> >> + */
>>> >> + load = div_u64(rate, 2) * timeout - 1;
>>> >> +
>>> >> + load = (load > LOAD_MAX) ? LOAD_MAX : load;
>>> >> + load = (load < LOAD_MIN) ? LOAD_MIN : load;
>>> >> +
>>> >> + spin_lock(&wdt->lock);
>>> >> + wdt->load_val = load;
>>> >> + /* roundup timeout to closest positive integer value */
>>> >> + wdt->timeout = div_u64((load + 1) * 2 + (rate / 2), rate);
>> >
>> > Look in linux/kernel.h, use the
>> > DIV_ROUND_CLOSEST() macro instead of this.
> OK.
>
Linus,
Now i remember why i didn't choose DIV_ROUND_CLOSEST in V1 of this patch.
As it is a u64 division, i get following compilation error if i use
DIV_ROUND_CLOSEST. I wasn't sure if inclusion of some header file can remove
this error, and so i used div_u64.
error:
"undefined reference to '__aeabi_uldivmod'"
Do you have some other solution to fix this error??
viresh.
next prev parent reply other threads:[~2010-07-27 4:50 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-05-20 8:33 [PATCH] Watchdog: Adding support for ARM Primecell SP805 Watchdog Viresh KUMAR
2010-06-02 7:48 ` Russell King - ARM Linux
2010-06-02 7:57 ` Viresh KUMAR
2010-07-18 20:29 ` Linus Walleij
2010-07-19 5:07 ` Viresh KUMAR
2010-07-27 4:50 ` Viresh KUMAR [this message]
2010-07-27 22:25 ` Linus Walleij
2010-07-28 4:02 ` Viresh KUMAR
2010-07-28 23:14 ` Linus Walleij
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