From: robherring2@gmail.com (Rob Herring)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 3/3] ARM: twd_smp: add clock api support
Date: Fri, 01 Oct 2010 13:47:15 -0500 [thread overview]
Message-ID: <4CA62CB3.1060909@gmail.com> (raw)
In-Reply-To: <20101001183431.GB22533@n2100.arm.linux.org.uk>
On 10/01/2010 01:34 PM, Russell King - ARM Linux wrote:
> On Fri, Oct 01, 2010 at 11:22:31AM -0700, Colin Cross wrote:
>> The timer APIs require that a timer take at least as long as requested
>> to fire. If you change the TWD prescaler before the CPU frequency
>> increases, or after the CPU frequency decreases, the timer interrupt
>> will not fire until a small time after the requested time.
>
> That maybe - and for TWD which is used for local timer purposes only,
> that's fine. What wouldn't be fine is if your clocksource counter
> changes frequency...
>
> In any case, I'm not sure that passing in a struct clk pointer is
> really the right way to go - the point of the clk API is to remove
> such passing of static structures.
>
> How about instead using clk_get_sys() to obtain a clock for the TWD?
Okay. Opinions on the name: periphclk, arm_twd, twd?
>
> Do we need separate connection IDs for each TWD, or are all TWDs in
> a system always clocked together?
A9 is 1 clock for all. Probably is likely that they will always be
symmetric.
Rob
next prev parent reply other threads:[~2010-10-01 18:47 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-30 22:49 [PATCH 1/3] ARM: move timer-sp.c from versatile to common Rob Herring
2010-09-30 22:49 ` [PATCH 3/3] ARM: twd_smp: add clock api support Rob Herring
2010-10-01 0:49 ` Colin Cross
2010-10-01 2:03 ` Rob Herring
2010-10-01 2:30 ` Colin Cross
2010-10-01 3:14 ` Rob Herring
2010-10-01 3:27 ` Colin Cross
2010-10-01 17:04 ` Rob Herring
2010-10-01 18:22 ` Colin Cross
2010-10-01 18:34 ` Russell King - ARM Linux
2010-10-01 18:47 ` Rob Herring [this message]
2010-10-01 2:39 ` [PATCH 1/3] ARM: move timer-sp.c from versatile to common Jean-Christophe PLAGNIOL-VILLARD
2010-10-01 3:23 ` Rob Herring
2010-10-01 8:24 ` Russell King - ARM Linux
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