From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tero Kristo Subject: Re: [RFC PATCH] clk: ti: set CLK_SET_RATE_NO_REPARENT for ti,mux-clock Date: Thu, 3 Jul 2014 10:41:22 +0300 Message-ID: <53B50922.7070402@ti.com> References: <1402992272-21413-1-git-send-email-tomi.valkeinen@ti.com> <1402992272-21413-2-git-send-email-tomi.valkeinen@ti.com> <53A2CA7A.60206@ti.com> <20140701194833.GH13396@saruman.home> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from comal.ext.ti.com ([198.47.26.152]:42797 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755531AbaGCHkh (ORCPT ); Thu, 3 Jul 2014 03:40:37 -0400 In-Reply-To: <20140701194833.GH13396@saruman.home> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: balbi@ti.com Cc: Tomi Valkeinen , Paul Walmsley , Mike Turquette , linux-omap@vger.kernel.org, Nishanth Menon On 07/01/2014 10:48 PM, Felipe Balbi wrote: > Hi, > > On Thu, Jun 19, 2014 at 02:33:14PM +0300, Tero Kristo wrote: >> On 06/17/2014 11:04 AM, Tomi Valkeinen wrote: >>> When setting the rate of a clock, by default the clock framework will >>> change the parent of the clock to the most suitable one in >>> __clk_mux_determine_rate() (most suitable by looking at the clock rate). >>> >>> This is a rather dangerous default, and causes problems on AM43x when >>> using display and ethernet. There are multiple ways to select the clock >>> muxes on AM43x, and some of those clock paths have the same source >>> clocks for display and ethernet. When changing the clock rate for the >>> display subsystem, the clock framework decides to change the display mux >> >from the dedicated display PLL to a shared PLL which is used by the >>> ethernet, and then changes the rate of the shared PLL, breaking the >>> ethernet. >>> >>> As I don't think there ever is a case where we want the clock framework >>> to automatically change the parent clock of a clock mux, this patch sets >>> the CLK_SET_RATE_NO_REPARENT for all ti,mux-clocks. >>> >>> Signed-off-by: Tomi Valkeinen >>> --- >>> drivers/clk/ti/mux.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/clk/ti/mux.c b/drivers/clk/ti/mux.c >>> index 0197a478720c..e9d650e51287 100644 >>> --- a/drivers/clk/ti/mux.c >>> +++ b/drivers/clk/ti/mux.c >>> @@ -160,7 +160,7 @@ static void of_mux_clk_setup(struct device_node *node) >>> u8 clk_mux_flags = 0; >>> u32 mask = 0; >>> u32 shift = 0; >>> - u32 flags = 0; >>> + u32 flags = CLK_SET_RATE_NO_REPARENT; >>> >>> num_parents = of_clk_get_parent_count(node); >>> if (num_parents < 2) { >>> >> >> Thanks, queued for 3.16-rc fixes. > > did you skip a few -rcs by any chance? Looks like this could've been > merged on v3.16-rc3... Just checking. This goes through Mike's clk tree, so there is extra latency there. Not sure when he plans to send next pull-req for clk-fixes to linux-master. -Tero