Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752298AbbHMIfY (ORCPT ); Thu, 13 Aug 2015 04:35:24 -0400 Received: from mail-wi0-f181.google.com ([209.85.212.181]:33866 "EHLO mail-wi0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752107AbbHMIfU (ORCPT ); Thu, 13 Aug 2015 04:35:20 -0400 Message-ID: <55CC56C4.8080201@linaro.org> Date: Thu, 13 Aug 2015 10:35:16 +0200 From: Daniel Lezcano User-Agent: Mozilla/5.0 (X11; Linux i686; rv:31.0) Gecko/20100101 Thunderbird/31.8.0 MIME-Version: 1.0 To: Yingjoe Chen , Daniel Kurtz , Stephen Boyd , Thomas Gleixner CC: James Liao , Russell King , srv_heupstream , Arnd Bergmann , "open list:OPEN FIRMWARE AND..." , Catalin Marinas , Michael Turquette , "linux-kernel@vger.kernel.org" , Olof Johansson , Rob Herring , linux-mediatek@lists.infradead.org, Sascha Hauer , Matthias Brugger , linux-clk@vger.kernel.org, "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH v2 1/5] clocksource: mediatek: do not enable GPT_CLK_EVT when setup References: <1437552878-3684-1-git-send-email-yingjoe.chen@mediatek.com> In-Reply-To: <1437552878-3684-1-git-send-email-yingjoe.chen@mediatek.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3625 Lines: 98 On 07/22/2015 10:14 AM, Yingjoe Chen wrote: > Spurious mtk timer interrupt is noticed at boot and cause kernel > crash. It seems if GPT is enabled, it will latch irq status even > when its IRQ is disabled. When irq is enabled afterward, we see > spurious interrupt. > Change init flow to only enable GPT_CLK_SRC at mtk_timer_init. > > Acked-by: Matthias Brugger > Reviewed-by: Daniel Kurtz > Signed-off-by: Yingjoe Chen > --- > > Update to my patch [1], added __init as Daniel suggest. This is the > only patch that need to change in that series, so I only sent this one. > > http://lists.infradead.org/pipermail/linux-mediatek/2015-July/001545.html > > drivers/clocksource/mtk_timer.c | 16 ++++++++++------ > 1 file changed, 10 insertions(+), 6 deletions(-) > > diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c > index 68ab423..2ba5b66 100644 > --- a/drivers/clocksource/mtk_timer.c > +++ b/drivers/clocksource/mtk_timer.c > @@ -156,9 +156,11 @@ static void mtk_timer_global_reset(struct mtk_clock_event_device *evt) > writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG); > } > > -static void > -mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option) > +static void __init mtk_timer_setup(struct mtk_clock_event_device *evt, > + u8 timer, u8 option, bool enable) > { > + u32 val; > + > writel(TIMER_CTRL_CLEAR | TIMER_CTRL_DISABLE, > evt->gpt_base + TIMER_CTRL_REG(timer)); > > @@ -167,8 +169,10 @@ mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option) > > writel(0x0, evt->gpt_base + TIMER_CMP_REG(timer)); > > - writel(TIMER_CTRL_OP(option) | TIMER_CTRL_ENABLE, > - evt->gpt_base + TIMER_CTRL_REG(timer)); > + val = TIMER_CTRL_OP(option); > + if (enable) > + val |= TIMER_CTRL_ENABLE; > + writel(val, evt->gpt_base + TIMER_CTRL_REG(timer)); Instead of the 'enable' new option, I prefer a test with 'timer' with a comment: /* * the timer hw is broken in that way ... bla bla, so we only * enable the clocksource ... */ if (timer == GPT_CLK_SRC) val |= TIMER_CTRL_ENABLE; That said, can you have a look at commit 1096be08 ? "clockevents: sun5i: Fix setup_irq init sequence" first and check if moving the interrupt request after the clockevents_config_and_register could fix your issue. > } > > static void mtk_timer_enable_irq(struct mtk_clock_event_device *evt, u8 timer) > @@ -235,12 +239,12 @@ static void __init mtk_timer_init(struct device_node *node) > evt->ticks_per_jiffy = DIV_ROUND_UP(rate, HZ); > > /* Configure clock source */ > - mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN); > + mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN, true); > clocksource_mmio_init(evt->gpt_base + TIMER_CNT_REG(GPT_CLK_SRC), > node->name, rate, 300, 32, clocksource_mmio_readl_up); > > /* Configure clock event */ > - mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT); > + mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT, false); > clockevents_config_and_register(&evt->dev, rate, 0x3, > 0xffffffff); -- Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- 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/