Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932075AbbGAOWR (ORCPT ); Wed, 1 Jul 2015 10:22:17 -0400 Received: from mail-yk0-f178.google.com ([209.85.160.178]:34418 "EHLO mail-yk0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754023AbbGAOWP (ORCPT ); Wed, 1 Jul 2015 10:22:15 -0400 MIME-Version: 1.0 In-Reply-To: <1435633127-31952-2-git-send-email-jamesjj.liao@mediatek.com> References: <1435633127-31952-1-git-send-email-jamesjj.liao@mediatek.com> <1435633127-31952-2-git-send-email-jamesjj.liao@mediatek.com> From: Daniel Kurtz Date: Wed, 1 Jul 2015 22:21:55 +0800 X-Google-Sender-Auth: AgSaJjX8VL1sirjZDeHX6M0Q_0k Message-ID: Subject: Re: [PATCH v2 1/4] clk: mediatek: mt8173: Fix enabling of critical clocks To: James Liao Cc: Matthias Brugger , Mike Turquette , Stephen Boyd , srv_heupstream , Ricky Liang , Rob Herring , Sascha Hauer , "open list:OPEN FIRMWARE AND..." , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , linux-mediatek@lists.infradead.org, Sascha Hauer Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4359 Lines: 116 Hi James, To be precise, it is the CLK_TOP clocks that have CLK_APMIXED PLLs as their parents, so we cannot enable the CLK_TOP critical clocks until the CLK_APMIXED clocks have all been registered. Please add something like the above to the commit message. More comments inline... On Tue, Jun 30, 2015 at 10:58 AM, James Liao wrote: > From: Sascha Hauer > > On the MT8173 the clocks are provided by different units. To enable > the critical clocks we must be sure that all parent clocks are already > registered, otherwise the parents of the critical clocks end up being > unused and get disabled later. To find a place where all parents are > registered we try each time after we've registered some clocks if > all known providers are present now and only then we enable the critical > clocks > > Signed-off-by: Sascha Hauer > Signed-off-by: James Liao > --- > drivers/clk/mediatek/clk-mt8173.c | 26 +++++++++++++++++++++----- > 1 file changed, 21 insertions(+), 5 deletions(-) > > diff --git a/drivers/clk/mediatek/clk-mt8173.c b/drivers/clk/mediatek/clk-mt8173.c > index 4b9e04c..c483336 100644 > --- a/drivers/clk/mediatek/clk-mt8173.c > +++ b/drivers/clk/mediatek/clk-mt8173.c > @@ -700,6 +700,22 @@ static const struct mtk_composite peri_clks[] __initconst = { > MUX(CLK_PERI_UART3_SEL, "uart3_ck_sel", uart_ck_sel_parents, 0x40c, 3, 1), > }; > > +static struct clk_onecell_data *mt8173_top_clk_data; > +static struct clk_onecell_data *mt8173_pll_clk_data; These globals can be: __initdata > + > +static void mtk_clk_enable_critical(void) And this function is: static void __init Other than the above, this one is: Reviewed-by: Daniel Kurtz -Dan > +{ > + if (!mt8173_top_clk_data || !mt8173_pll_clk_data) > + return; > + > + clk_prepare_enable(mt8173_pll_clk_data->clks[CLK_APMIXED_ARMCA15PLL]); > + clk_prepare_enable(mt8173_pll_clk_data->clks[CLK_APMIXED_ARMCA7PLL]); > + clk_prepare_enable(mt8173_top_clk_data->clks[CLK_TOP_MEM_SEL]); > + clk_prepare_enable(mt8173_top_clk_data->clks[CLK_TOP_DDRPHYCFG_SEL]); > + clk_prepare_enable(mt8173_top_clk_data->clks[CLK_TOP_CCI400_SEL]); > + clk_prepare_enable(mt8173_top_clk_data->clks[CLK_TOP_RTC_SEL]); > +} > + > static void __init mtk_topckgen_init(struct device_node *node) > { > struct clk_onecell_data *clk_data; > @@ -712,19 +728,19 @@ static void __init mtk_topckgen_init(struct device_node *node) > return; > } > > - clk_data = mtk_alloc_clk_data(CLK_TOP_NR_CLK); > + mt8173_top_clk_data = clk_data = mtk_alloc_clk_data(CLK_TOP_NR_CLK); > > mtk_clk_register_factors(root_clk_alias, ARRAY_SIZE(root_clk_alias), clk_data); > mtk_clk_register_factors(top_divs, ARRAY_SIZE(top_divs), clk_data); > mtk_clk_register_composites(top_muxes, ARRAY_SIZE(top_muxes), base, > &mt8173_clk_lock, clk_data); > > - clk_prepare_enable(clk_data->clks[CLK_TOP_CCI400_SEL]); > - > r = of_clk_add_provider(node, of_clk_src_onecell_get, clk_data); > if (r) > pr_err("%s(): could not register clock provider: %d\n", > __func__, r); > + > + mtk_clk_enable_critical(); > } > CLK_OF_DECLARE(mtk_topckgen, "mediatek,mt8173-topckgen", mtk_topckgen_init); > > @@ -818,13 +834,13 @@ static void __init mtk_apmixedsys_init(struct device_node *node) > { > struct clk_onecell_data *clk_data; > > - clk_data = mtk_alloc_clk_data(CLK_APMIXED_NR_CLK); > + mt8173_pll_clk_data = clk_data = mtk_alloc_clk_data(CLK_APMIXED_NR_CLK); > if (!clk_data) > return; > > mtk_clk_register_plls(node, plls, ARRAY_SIZE(plls), clk_data); > > - clk_prepare_enable(clk_data->clks[CLK_APMIXED_ARMCA15PLL]); > + mtk_clk_enable_critical(); > } > CLK_OF_DECLARE(mtk_apmixedsys, "mediatek,mt8173-apmixedsys", > mtk_apmixedsys_init); > -- > 1.8.1.1.dirty > -- 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/