Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933547AbaGPImR (ORCPT ); Wed, 16 Jul 2014 04:42:17 -0400 Received: from hqemgate16.nvidia.com ([216.228.121.65]:6325 "EHLO hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933052AbaGPImK (ORCPT ); Wed, 16 Jul 2014 04:42:10 -0400 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Wed, 16 Jul 2014 01:34:43 -0700 Date: Wed, 16 Jul 2014 11:41:51 +0300 From: Peter De Schrijver To: Thierry Reding CC: Rob Herring , Pawel Moll , "Mark Rutland" , Ian Campbell , Kumar Gala , Stephen Warren , Russell King , Prashant Gaikwad , Mike Turquette , Joseph Lo , Alex Courbot , "Sebastian Hesselbarth" , Tuomas Tynkkynen , "devicetree@vger.kernel.org" , "linux-tegra@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH 5/6] clk: tegra: Add support for Tegra132 CAR clocks Message-ID: <20140716084151.GN23218@tbergstrom-lnx.Nvidia.com> References: <1405437890-6468-1-git-send-email-pdeschrijver@nvidia.com> <1405437890-6468-6-git-send-email-pdeschrijver@nvidia.com> <20140716074410.GF7978@ulmo> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20140716074410.GF7978@ulmo> X-NVConfidentiality: public User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 16, 2014 at 09:44:10AM +0200, Thierry Reding wrote: > * PGP Signed by an unknown key > > On Tue, Jul 15, 2014 at 06:24:35PM +0300, Peter De Schrijver wrote: > > Tegra132 CAR supports almost the same clocks as Tegra124 CAR. This patch > > deals with the small differences. > > > > -- > > I'm not entirely sure why the soc_therm clock needs to be enabled on Tegra132, > > but turning it off results in a system hang. I presume this might be because > > of fastboot initializing soc_therm. > > > > Signed-off-by: Peter De Schrijver > > --- > > drivers/clk/tegra/clk-tegra124.c | 32 ++++++++++++++++++++++++++++++++ > > 1 files changed, 32 insertions(+), 0 deletions(-) > > > > diff --git a/drivers/clk/tegra/clk-tegra124.c b/drivers/clk/tegra/clk-tegra124.c > > index 80efe51..b857aab 100644 > > --- a/drivers/clk/tegra/clk-tegra124.c > > +++ b/drivers/clk/tegra/clk-tegra124.c > > @@ -1369,6 +1369,7 @@ static struct tegra_clk_init_table init_table[] __initdata = { > > {TEGRA124_CLK_XUSB_HS_SRC, TEGRA124_CLK_PLL_U_60M, 60000000, 0}, > > {TEGRA124_CLK_XUSB_FALCON_SRC, TEGRA124_CLK_PLL_RE_OUT, 224000000, 0}, > > {TEGRA124_CLK_XUSB_HOST_SRC, TEGRA124_CLK_PLL_RE_OUT, 112000000, 0}, > > + {TEGRA124_CLK_SOC_THERM, TEGRA124_CLK_PLL_P, 51000000, 0}, > > /* This MUST be the last entry. */ > > {TEGRA124_CLK_CLK_MAX, TEGRA124_CLK_CLK_MAX, 0, 0}, > > }; > > @@ -1378,9 +1379,25 @@ static void __init tegra124_clock_apply_init_table(void) > > tegra_init_from_table(init_table, clks, TEGRA124_CLK_CLK_MAX); > > } > > > > +enum { > > + TEGRA124_CLK, > > + TEGRA132_CLK, > > +}; > > I'd prefer this to be something like: > > struct tegra_car_soc { > bool has_ccplex_clk; > }; > > static const struct tegra_car_soc tegra124_car_soc = { > .has_ccplex_clk = false, > }; > > static const struct tegra_car_soc tegra132_car_soc = { > .has_ccplex_clk = true, > }; > > > +static const struct of_device_id tegra_clock_of_match[] = { > > + { .compatible = "nvidia,tegra124-car", .data = (void *)TEGRA124_CLK }, > > .data = &tegra124_car_soc, > > > + { .compatible = "nvidia,tegra132-car", .data = (void *)TEGRA132_CLK }, > > .data = &tegra132_car_soc, > > > static void __init tegra124_clock_init(struct device_node *np) > > { > > struct device_node *node; > > + const struct of_device_id *match; > > const struct tegra_car_soc *soc; > > > + uintptr_t id; > > > + match = of_match_node(tegra_clock_of_match, np); > > + id = (uintptr_t)match->data; > > soc = match->data; > > > > > clk_base = of_iomap(np, 0); > > if (!clk_base) { > > @@ -1416,6 +1433,20 @@ static void __init tegra124_clock_init(struct device_node *np) > > tegra_audio_clk_init(clk_base, pmc_base, tegra124_clks, &pll_a_params); > > tegra_pmc_clk_init(pmc_base, tegra124_clks); > > > > + if (id == TEGRA132_CLK) { > > if (soc->has_ccplex_clk) { > > That's somewhat more explicit and avoids a lot of ugly casting. > It also adds another struct + pointers to essentially store 1 bit. Which is why I decided to go this route. > > + int i; > > + > > + tegra124_clks[tegra_clk_cclk_g].present = false; > > + tegra124_clks[tegra_clk_cclk_lp].present = false; > > + tegra124_clks[tegra_clk_pll_x].present = false; > > + tegra124_clks[tegra_clk_pll_x_out0].present = false; > > + > > + /* Tegra132 requires the soc_therm clock to be always on */ > > + for (i = 0; i < ARRAY_SIZE(init_table); i++) { > > + if (init_table[i].clk_id == TEGRA124_CLK_SOC_THERM) > > + init_table[i].state = 1; > > I wonder if we could do this someplace else. If we could, then we'd have > the opportunity to make the init_table const. > The easiest solution would be to turn on soc_therm for Tegra124 and Tegra132. I don't think this would cause a measureable increase in power consumption. If you're ok with this, this logic could just be removed. Another solution would be to do an explicit clk_enable. PLL_P is already enabled so enabling this clock, does not require PLL locking and could be done before udelay() is available. Cheers, Peter. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/