From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: Re: [PATCH 3/4 v3][RFC] arm64: renesas: Add initial r8a7795 SoC support Date: Thu, 20 Aug 2015 09:43:34 +0200 Message-ID: References: <877fpdw3av.wl%kuninori.morimoto.gx@renesas.com> <20150818002018.31346.63666@quantum> <12310001.Bt8qbPIiMv@avalon> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <12310001.Bt8qbPIiMv@avalon> Sender: linux-sh-owner@vger.kernel.org To: Laurent Pinchart Cc: Michael Turquette , Kuninori Morimoto , Simon , Magnus , Linux-sh list , linux-clk@vger.kernel.org, "devicetree@vger.kernel.org" List-Id: devicetree@vger.kernel.org Hi Laurent, On Wed, Aug 19, 2015 at 11:29 PM, Laurent Pinchart wrote: >> > Also, while you're thinking about the perfect clock binding, please do >> > consider dropping clock-output-names if you can. Specifying clock-names >> > alongside the clocks property inside of the consumer node is a bit more >> > elegant in my opinion. This is also a bit easier if you think about >> > expressing your clock data with C inside of your provider driver. >> >> Makes sense. I don't think anything relies on the "clock-output-names" >> ... currently. >> >> I was going to use it for identifying the GIC clock, though: >> >> --- a/drivers/clk/shmobile/clk-mstp.c >> +++ b/drivers/clk/shmobile/clk-mstp.c >> @@ -144,6 +144,9 @@ cpg_mstp_clock_register(const char *name, const char >> *paren init.name = name; >> init.ops = &cpg_mstp_clock_ops; >> init.flags = CLK_IS_BASIC | CLK_SET_RATE_PARENT; >> + /* INTC-SYS is the module clock of the GIC, and must not be disabled >> */ >> + if (!strcmp(name, "intc-sys")) >> + init.flags |= CLK_ENABLE_HAND_OFF; >> init.parent_names = &parent_name; >> init.num_parents = 1; >> >> (FTR, on R-Car Gen3 the clock is called "intc-ap", not "intc-sys", doh...). >> >> This does put some reliance on (undocumented) naming in DT, though, so not >> having the "clock-output-names" would solve that. > > Using the clock name is indeed very messy, let's avoid that. > >> However, while "intc-sys"/"intc-ap" (if existent) is always MSTP408, MSTP408 >> is used for other modules on R-Car Gen1 and most older SoCs. so it would >> complicate the driver code. > > How about setting the flag based on information provided in DT ? Like scanning DT for the GIC, and looking for its clock? I don't want to add an explicit flag in DT, as it's not a hardware property, but a deficiency of the current GIC driver/subsystem. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.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