From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sudeep KarkadaNagesha Subject: Re: [PATCH v4 12/19] cpufreq: cpufreq-cpu0: remove device tree parsing for cpu nodes Date: Tue, 10 Sep 2013 11:56:17 +0100 Message-ID: <522EFAD1.4020709@arm.com> References: <1374492747-13879-1-git-send-email-Sudeep.KarkadaNagesha@arm.com> <1376991021-12160-1-git-send-email-Sudeep.KarkadaNagesha@arm.com> <1376991021-12160-13-git-send-email-Sudeep.KarkadaNagesha@arm.com> <522D93D7.4010307@arm.com> <20130909143253.GD4624@S2101-09.ap.freescale.net> <522DE822.3030907@arm.com> <20130910024404.GC5815@S2101-09.ap.freescale.net> Mime-Version: 1.0 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <20130910024404.GC5815@S2101-09.ap.freescale.net> Sender: linux-pm-owner@vger.kernel.org To: Shawn Guo Cc: Sudeep KarkadaNagesha , Guennadi Liakhovetski , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linux-pm@vger.kernel.org" , "devicetree@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" , Viresh Kumar , Greg Kroah-Hartman , Benjamin Herrenschmidt , Jonas Bonn , Michal Simek , "Rafael J. Wysocki" , "grant.likely@linaro.org" , "rob.herring@calxeda.com" List-Id: devicetree@vger.kernel.org On 10/09/13 03:44, Shawn Guo wrote: > On Mon, Sep 09, 2013 at 04:24:18PM +0100, Sudeep KarkadaNagesha wrote: >> Hi Shawn, >> >> Ok. But I am bit suspicious about devm_clk_get(cpu_dev, NULL). >> I don't understand completely as how the clock are registered(whether >> with dev_id or with connection_id). > > As the connection_id of devm_clk_get() call here is NULL, the clock > lookup should be registered with a proper dev_id in clk_register_clkdev() > call. And that's what you have seen with imx and shmobile code. > > >> A quick grep revealed that i.mx and shmobile is using conection id while >> registering. > > They are using dev_id. > Yes correct. I misunderstood, was expecting caller to pass dev and clk layer extract dev_name so that even when device name is changed the clk registration need not be changed. >> If the clock is registered with connection id and retrieved >> with cpu_dev(now dev_id is cpu0 and not cpufreq-cpu0), IIUC that would >> break. If we pass pdev->dev for clk_get, it should be fine but again >> IIUC it breaks highbank which gets all the information from DT. > > If the clock lookup is from DT, we should be just fine, since it will > work as long as the DT node with 'clocks' property (/cpus/cpu@0 in this > case) is attached to the struct device pointer of devm_clk_get() call. > This can be ignored if we are registering with "cpu0" as below in your patch. >> So only solution I can think of is to continue to have the code >> assigning (&pdev->dev)->of_node with cpu device node which is not clean >> and arguable as incorrect since there is no DT node for cpufreq-cpu0. >> I don't have a strong opinion though. >> >> Let me know how would you like to fix this. > > So we only need to change all clkdev registration to use "cpu0" as > dev_id intstead of "cpufreq-cpu0.0", something like below. > > And for imx, it should work even without the changes, because we have > device tree lookup ready there, and those clk_register_clkdev() calls > can just be removed now. But I prefer to include the change and leave > the cleanup to another patch for keeping the change log clear. > Ok makes sense, do you want me to include this patch also as fix. I can send a series to fix this if you OK: 1. Fix in cpufreq-cpu0 2. Fix in i.MX driver and platform file 3. Patch below Regards, Sudeep > > ---8<---------- > > diff --git a/arch/arm/mach-imx/clk-imx27.c b/arch/arm/mach-imx/clk-imx27.c > index c3cfa41..c6b40f3 100644 > --- a/arch/arm/mach-imx/clk-imx27.c > +++ b/arch/arm/mach-imx/clk-imx27.c > @@ -285,7 +285,7 @@ int __init mx27_clocks_init(unsigned long fref) > clk_register_clkdev(clk[ata_ahb_gate], "ata", NULL); > clk_register_clkdev(clk[rtc_ipg_gate], NULL, "imx21-rtc"); > clk_register_clkdev(clk[scc_ipg_gate], "scc", NULL); > - clk_register_clkdev(clk[cpu_div], NULL, "cpufreq-cpu0.0"); > + clk_register_clkdev(clk[cpu_div], NULL, "cpu0"); > clk_register_clkdev(clk[emi_ahb_gate], "emi_ahb" , NULL); > > mxc_timer_init(MX27_IO_ADDRESS(MX27_GPT1_BASE_ADDR), MX27_INT_GPT1); > diff --git a/arch/arm/mach-imx/clk-imx51-imx53.c b/arch/arm/mach-imx/clk-imx51-imx53.c > index 1a56a33..de1964c 100644 > --- a/arch/arm/mach-imx/clk-imx51-imx53.c > +++ b/arch/arm/mach-imx/clk-imx51-imx53.c > @@ -328,7 +328,7 @@ static void __init mx5_clocks_common_init(unsigned long rate_ckil, > clk_register_clkdev(clk[ssi2_ipg_gate], NULL, "imx-ssi.1"); > clk_register_clkdev(clk[ssi3_ipg_gate], NULL, "imx-ssi.2"); > clk_register_clkdev(clk[sdma_gate], NULL, "imx35-sdma"); > - clk_register_clkdev(clk[cpu_podf], NULL, "cpufreq-cpu0.0"); > + clk_register_clkdev(clk[cpu_podf], NULL, "cpu0"); > clk_register_clkdev(clk[iim_gate], "iim", NULL); > clk_register_clkdev(clk[dummy], NULL, "imx2-wdt.0"); > clk_register_clkdev(clk[dummy], NULL, "imx2-wdt.1"); > diff --git a/arch/arm/mach-shmobile/clock-r8a73a4.c b/arch/arm/mach-shmobile/clock-r8a73a4.c > index 8ea5ef6..5bd2e85 100644 > --- a/arch/arm/mach-shmobile/clock-r8a73a4.c > +++ b/arch/arm/mach-shmobile/clock-r8a73a4.c > @@ -555,7 +555,7 @@ static struct clk_lookup lookups[] = { > CLKDEV_CON_ID("pll2h", &pll2h_clk), > > /* CPU clock */ > - CLKDEV_DEV_ID("cpufreq-cpu0", &z_clk), > + CLKDEV_DEV_ID("cpu0", &z_clk), > > /* DIV6 */ > CLKDEV_CON_ID("zb", &div6_clks[DIV6_ZB]), > diff --git a/arch/arm/mach-shmobile/clock-sh73a0.c b/arch/arm/mach-shmobile/clock-sh73a0.c > index 1942eae..c92c023 100644 > --- a/arch/arm/mach-shmobile/clock-sh73a0.c > +++ b/arch/arm/mach-shmobile/clock-sh73a0.c > @@ -616,7 +616,7 @@ static struct clk_lookup lookups[] = { > CLKDEV_DEV_ID("smp_twd", &twd_clk), /* smp_twd */ > > /* DIV4 clocks */ > - CLKDEV_DEV_ID("cpufreq-cpu0", &div4_clks[DIV4_Z]), > + CLKDEV_DEV_ID("cpu0", &div4_clks[DIV4_Z]), > > /* DIV6 clocks */ > CLKDEV_CON_ID("vck1_clk", &div6_clks[DIV6_VCK1]), > >