From: viresh.kumar@st•com (Viresh Kumar)
To: linux-arm-kernel@lists•infradead.org
Subject: [Query] Common Clock Framework: How to handle clks enabled by default
Date: Tue, 17 Apr 2012 11:51:45 +0530 [thread overview]
Message-ID: <4F8D0BF9.7080802@st.com> (raw)
Hi,
How are we handling clocks which are enabled by bootloaders and are
required to be enabled, like, pll, cpu, ahb?
Following is example clk hierarchy:
osc(root)->pll->cpu->ahb->dma
Issue1: Now, when we do clk_enable() for dma, all these already enabled clocks
are re-enabled.
Issue2: On clk_disable() all are disabled and system hangs :(
There is one option CLK_IGNORE_UNUSED, which is used only for disabling
unused clocks. So that is not helpful here.
One way i could think of is not to give clk_gate support for these clocks,
so that they can never be disabled. Is this the preferred way?
I can't guarantee, but these clocks might be required to be disabled
for standby/sleep cases.
--
viresh
next reply other threads:[~2012-04-17 6:21 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-17 6:21 Viresh Kumar [this message]
2012-04-17 7:13 ` [Query] Common Clock Framework: How to handle clks enabled by default Shawn Guo
2012-04-17 7:25 ` Viresh Kumar
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