Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754796Ab3EVMyU (ORCPT ); Wed, 22 May 2013 08:54:20 -0400 Received: from mail-bk0-f47.google.com ([209.85.214.47]:47554 "EHLO mail-bk0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752633Ab3EVMyT (ORCPT ); Wed, 22 May 2013 08:54:19 -0400 Message-ID: <519CBFF5.3060900@linaro.org> Date: Wed, 22 May 2013 14:54:13 +0200 From: Daniel Lezcano User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 To: Lu Jingchang-B35083 CC: "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "john.stultz@linaro.org" , "tglx@linutronix.de" , "shawn.guo@linaro.org" , "s.hauer@pengutronix.de" Subject: Re: [PATCH v4] clocksource: add Vybrid Family pit timer support References: <1369121274-9371-1-git-send-email-b35083@freescale.com> <519B48F4.8050005@linaro.org> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2253 Lines: 73 On 05/22/2013 11:47 AM, Lu Jingchang-B35083 wrote: > [ ... ] >> >>> +} >>> + >>> +static void __init pit_timer_init(struct device_node *np) { >>> + struct clk *pit_clk; >>> + void __iomem *timer_base; >>> + int irq; >>> + >>> + timer_base = of_iomap(np, 0); >>> + BUG_ON(!timer_base); >> >> You raise a bug and then you go ahead setting up the address with an >> invalid value, leading to a random crash. > [Lu Jingchang-B35083] > The BUG_ON() will call BUG() if condition is true. It will print the stack trace and the current process will die, it won't go ahead, won't it? Thanks! Pff, right. I just puzzled myself. Never mind. >>> + /* >>> + * PIT0 and PIT1 can be chained to build a 64-bit timer, >>> + * so choose PIT2 as clocksource, PIT3 as clockevent device, >>> + * and leave PIT0 and PIT1 unused for anyone else who needs them. >>> + */ >>> + clksrc_base = timer_base + PITn_OFFSET(2); >>> + clkevt_base = timer_base + PITn_OFFSET(3); >>> + >>> + irq = irq_of_parse_and_map(np, 0); >>> + >>> + pit_clk = of_clk_get(np, 0); >>> + BUG_ON(IS_ERR(pit_clk)); >>> + >>> + BUG_ON(clk_prepare_enable(pit_clk)); >> >> Same here. >> >>> + cycle_per_jiffy = clk_get_rate(pit_clk)/(HZ); >>> + >>> + /* enable the pit module */ >>> + __raw_writel(~PITMCR_MDIS, timer_base + PITMCR); >>> + >>> + BUG_ON(pit_clocksource_init(pit_clk)); >>> + >>> + pit_clockevent_init(pit_clk, irq); >> >> Please, remove these BUG_ON, this is inconsistent especially with a one >> call init function. If pit_timer_init can't be initialized, just pr_err >> + BUG. > [Lu Jingchang-B35083] > Do you mean that I should not use the BUG_ON or I need print an error information by pr_err before BUG. Thanks! Actually, my initial comment was wrong, so you can ignore it. Thank -- Daniel -- 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/