From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH 07/13] ARM: dts: r8a7792: initial SoC device tree Date: Mon, 13 Jun 2016 14:24:58 +0300 Message-ID: <7d93d81d-cca9-e434-6488-0ea839f81663@cogentembedded.com> References: <13205049.n7pM8utpHF@wasted.cogentembedded.com> <2539026.OyU5nvpxa6@wasted.cogentembedded.com> <20160601005751.GG20527@verge.net.au> <20160610010245.GA10152@verge.net.au> <8efb1c7e-5463-2556-744c-d327886d92d4@cogentembedded.com> <1b9a4cf4-1101-ccbf-772b-49b8a689a1b6@cogentembedded.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-renesas-soc-owner@vger.kernel.org To: Geert Uytterhoeven , Kuninori Morimoto Cc: Simon Horman , "open list:MEDIA DRIVERS FOR RENESAS - FCP" , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , "devicetree@vger.kernel.org" , Magnus Damm , Russell King , "linux-arm-kernel@lists.infradead.org" List-Id: devicetree@vger.kernel.org On 6/13/2016 10:12 AM, Geert Uytterhoeven wrote: >>>> The only problem I'm seeing (again) is the RCAN clock failing to >>>> register: >>>> >>>> rcar_gen2_cpg_clocks_init: failed to register cpg_clocks rcan clock (-12) >>>> >>>> I was going to look at it yesterday but (wrongly) thought it somehow >>>> cured itself... I'll look at it now. >>> >>> The RCAN parent is the second clock in the CPG node's "clocks" property, >>> which you didn't provide. >> >> Actually, the things are more complex. The figure 7.1c suggests that the >> RCAN clock has different parent on R8A7792 than on the other SoCs -- namely >> PLL1/VCO 1/4. That may be, since there's just no USB_EXTAL signal on this >> SoC (it doesn't seem to support any USB IPs). Which means the >> 'clk-rcar-gen2' driver can't work with the RCAN clock in its current form. > > Right, I had forgotten about that. > Fortunately the clk-rcar-gen2 driver has a sane failure mode for this case ;-) What do you mean? > it seems the RCAN clock can just be modeled as a fixed clock. However, > its divider value isn't clear to me, IIRC, the fixed RCAN divisor was equal to 6. [...] > Gr{oetje,eeting}s, > > Geert MBR, Sergei