From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162012AbcE3XJv (ORCPT ); Mon, 30 May 2016 19:09:51 -0400 Received: from mail-wm0-f42.google.com ([74.125.82.42]:36192 "EHLO mail-wm0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161683AbcE3XJs (ORCPT ); Mon, 30 May 2016 19:09:48 -0400 Subject: Re: [PATCH 2/5] clocksource: rockchip: remove unnecessary clear irq before request_irq To: Caesar Wang , Heiko Stuebner References: <1464169802-6033-1-git-send-email-wxt@rock-chips.com> <1464169802-6033-3-git-send-email-wxt@rock-chips.com> Cc: dianders@chromium.org, briannorris@google.com, smbarber@google.com, linux-rockchip@lists.infradead.org, Thomas Gleixner , cf@rock-chips.com, huangtao@rock-chips.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org From: Daniel Lezcano Message-ID: <574CC839.60608@linaro.org> Date: Tue, 31 May 2016 01:09:45 +0200 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <1464169802-6033-3-git-send-email-wxt@rock-chips.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 On 05/25/2016 11:49 AM, Caesar Wang wrote: > From: Huang Tao > > rk_timer_interrupt_clear and rk_timer_disable is unnecessary before > request_irq. Timer should keep disabled before booting Linux. That's true in the perfect world :/ Some version has u-boot letting the timer with irq enabled, therefore as soon as request_irq is done, an irq fires and leads to a kernel panic. On the other side, this timer is not used on the other rockchip version than rk3399 because of no need of a broadcast timer, so removing these two lines may be acceptable. Can try the changes with another board, eg rk3288 (and forcing to use this timer). Can you do the test and confirm it does not break with different version of u-boot ? Thanks! -- Daniel > Signed-off-by: Huang Tao > Cc: Daniel Lezcano > Cc: Thomas Gleixner > Cc: Heiko Stuebner > Tested-by: Jianqun Xu > Signed-off-by: Caesar Wang > --- > > drivers/clocksource/rockchip_timer.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/drivers/clocksource/rockchip_timer.c b/drivers/clocksource/rockchip_timer.c > index b991b28..b93fed6 100644 > --- a/drivers/clocksource/rockchip_timer.c > +++ b/drivers/clocksource/rockchip_timer.c > @@ -158,9 +158,6 @@ static void __init rk_timer_init(struct device_node *np) > ce->cpumask = cpumask_of(0); > ce->rating = 250; > > - rk_timer_interrupt_clear(ce); > - rk_timer_disable(ce); > - > ret = request_irq(irq, rk_timer_interrupt, IRQF_TIMER, TIMER_NAME, ce); > if (ret) { > pr_err("Failed to initialize '%s': %d\n", TIMER_NAME, ret); > -- Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog