From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: Re: [PATCH 07/13] ARM: dts: r8a7792: initial SoC device tree Date: Mon, 13 Jun 2016 13:48:33 +0200 Message-ID: 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> <7d93d81d-cca9-e434-6488-0ea839f81663@cogentembedded.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <7d93d81d-cca9-e434-6488-0ea839f81663-M4DtvfQ/ZS1MRgGoP+s0PdBPR1lH4CV8@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sergei Shtylyov Cc: Kuninori Morimoto , Simon Horman , "open list:MEDIA DRIVERS FOR RENESAS - FCP" , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Magnus Damm , Russell King , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" List-Id: devicetree@vger.kernel.org Hi Sergei, On Mon, Jun 13, 2016 at 1:24 PM, Sergei Shtylyov wrote: > 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? I mean that it failed due to the missing parent clock, instead of continuing silently with a wrong clock rate. >> 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. 1560 / 6 != 15.9. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html