From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nishanth Menon Subject: Re: [PATCH 2/2] ARM: omap5/dra7xx: Fix counter frequency drift for AM572x errata i856. Date: Wed, 17 Dec 2014 09:53:59 -0600 Message-ID: <20141217155359.GA26990@kahuna> References: <358281a880ccd89873efeea75edaa6c953eac2bd.1418421100.git.lsorense@csclub.uwaterloo.ca> <20141214044517.GD24110@csclub.uwaterloo.ca> <549018EC.8020207@ti.com> <20141216145856.GA23358@kahuna> <54918357.8060801@ti.com> <20141217145533.GS24110@csclub.uwaterloo.ca> <20141217152225.GA737@kahuna> <20141217152710.GT24110@csclub.uwaterloo.ca> <5491A501.100@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: Content-Disposition: inline In-Reply-To: <5491A501.100@ti.com> Sender: linux-kernel-owner@vger.kernel.org To: Tero Kristo Cc: Lennart Sorensen , Lokesh Vutla , linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sekhar Nori List-Id: linux-omap@vger.kernel.org On 17:45-20141217, Tero Kristo wrote: > On 12/17/2014 05:27 PM, Lennart Sorensen wrote: > >On Wed, Dec 17, 2014 at 09:22:25AM -0600, Nishanth Menon wrote: > >>A clock mux might do the job? > >> > >>value 1, 2 , 3 will imply sysclk1 / 610 > >>value of 0 implies fixed 32768 > >> > >>soemthing like > >>sys_clk32_crystal { > >> compatible = "fixed-clock"; > >> clock-frequency = <32768>; > >>} > >> > >>sys_clk32_pseudo { > >> compatible = "fixed-clock"; > >> compatible = "fixed-factor-clock"; > >> clocks = <&sys_clkin1>; > >> clock-mult = <1>; > >> clock-div = <610>; > >>} > >> > >>sys_32k_ck: sys_32k_ck { > >> compatible = "ti,mux-clock"; > >> clocks = <&sys_clk32_crystal>, <&sys_clk32_pseudo>, <&sys_clk32_pseudo>, <&sys_clk32_pseudo>; > >>}; > >> > >>I think... The only issue is that the BOOTSTRAP register is not around > >>the usual CM1,2 address region... > > > >OK, I like where that idea is headed. That looks promising. > > > > Yea clock mux can be used. However, we don't have support for DRA7 > control module clocks in the DT yet. I have posted patches with > support towards this a couple of weeks back, but they need some > revising. > > Thus, we maybe need to apply the timer patches as is for now, and > fix the clock tree a bit later. Sounds good to me, could you propose a patch in list? -- Regards, Nishanth Menon