From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH v2] xen/arm: register clocks used by the hypervisor To: Stefano Stabellini , Dirk Behme References: <1467282752-14053-1-git-send-email-dirk.behme@de.bosch.com> Cc: linux-arm-kernel@lists.infradead.org, Mark Rutland , devicetree@vger.kernel.org, xen-devel@lists.xenproject.org, linux-clk@vger.kernel.org, Michael Turquette , Stephen Boyd From: Julien Grall Message-ID: <577BBC1A.8020209@arm.com> Date: Tue, 5 Jul 2016 14:54:34 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed List-ID: On 05/07/16 14:53, Stefano Stabellini wrote: > On Thu, 30 Jun 2016, Dirk Behme wrote: >> +- clocks: one or more clocks to be registered. >> + Xen hypervisor drivers might replace native drivers, resulting in >> + clocks not registered by these native drivers. To avoid that these >> + unregistered clocks are disabled, then, e.g. by clk_disable_unused(), >> + register them in the hypervisor node. >> + An example for this are the clocks of the serial driver. If the clocks >> + used by the serial hardware interface are not registered by the serial >> + driver the serial output might stop once clk_disable_unused() is called. > > What if we use the "status" property of the clocks? Could we set it to > "disabled" in Xen? Would that be enough for Linux to leave them alone? clocks could be shared between multiple devices. So it is not possible to disable the clock. -- Julien Grall