From patchwork Thu Mar 4 07:37:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 393158 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77C9AC43333 for ; Thu, 4 Mar 2021 07:39:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EB9E64F1E for ; Thu, 4 Mar 2021 07:39:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232654AbhCDHii (ORCPT ); Thu, 4 Mar 2021 02:38:38 -0500 Received: from muru.com ([72.249.23.125]:39340 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232714AbhCDHi0 (ORCPT ); Thu, 4 Mar 2021 02:38:26 -0500 Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id 97DC4810E; Thu, 4 Mar 2021 07:38:23 +0000 (UTC) From: Tony Lindgren To: Daniel Lezcano , Thomas Gleixner Cc: Keerthy , linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Tero Kristo Subject: [PATCH 1/2] clocksource/drivers/timer-ti-dm: Prepare to handle dra7 timer wrap issue Date: Thu, 4 Mar 2021 09:37:36 +0200 Message-Id: <20210304073737.15810-2-tony@atomide.com> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210304073737.15810-1-tony@atomide.com> References: <20210304073737.15810-1-tony@atomide.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org There is a timer wrap issue on dra7 for the ARM architected timer. In a typical clock configuration the timer fails to wrap after 388 days. To work around the issue, we need to use timer-ti-dm timers instead. Let's prepare for adding support for percpu timers by adding a common dmtimer_clkevt_init_common() and call it from dmtimer_clockevent_init(). This patch makes no intentional functional changes. Signed-off-by: Tony Lindgren --- drivers/clocksource/timer-ti-dm-systimer.c | 72 +++++++++++++++------- 1 file changed, 49 insertions(+), 23 deletions(-) diff --git a/drivers/clocksource/timer-ti-dm-systimer.c b/drivers/clocksource/timer-ti-dm-systimer.c --- a/drivers/clocksource/timer-ti-dm-systimer.c +++ b/drivers/clocksource/timer-ti-dm-systimer.c @@ -528,17 +528,18 @@ static void omap_clockevent_unidle(struct clock_event_device *evt) writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->wakeup); } -static int __init dmtimer_clockevent_init(struct device_node *np) +static int __init dmtimer_clkevt_init_common(struct dmtimer_clockevent *clkevt, + struct device_node *np, + unsigned int features, + const struct cpumask *cpumask, + const char *name, + int rating) { - struct dmtimer_clockevent *clkevt; struct clock_event_device *dev; struct dmtimer_systimer *t; + unsigned long irqflags; int error; - clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL); - if (!clkevt) - return -ENOMEM; - t = &clkevt->t; dev = &clkevt->dev; @@ -546,25 +547,23 @@ static int __init dmtimer_clockevent_init(struct device_node *np) * We mostly use cpuidle_coupled with ARM local timers for runtime, * so there's probably no use for CLOCK_EVT_FEAT_DYNIRQ here. */ - dev->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; - dev->rating = 300; + dev->features = features; + dev->rating = rating; dev->set_next_event = dmtimer_set_next_event; dev->set_state_shutdown = dmtimer_clockevent_shutdown; dev->set_state_periodic = dmtimer_set_periodic; dev->set_state_oneshot = dmtimer_clockevent_shutdown; dev->set_state_oneshot_stopped = dmtimer_clockevent_shutdown; dev->tick_resume = dmtimer_clockevent_shutdown; - dev->cpumask = cpu_possible_mask; + dev->cpumask = cpumask; dev->irq = irq_of_parse_and_map(np, 0); - if (!dev->irq) { - error = -ENXIO; - goto err_out_free; - } + if (!dev->irq) + return -ENXIO; error = dmtimer_systimer_setup(np, &clkevt->t); if (error) - goto err_out_free; + return error; clkevt->period = 0xffffffff - DIV_ROUND_CLOSEST(t->rate, HZ); @@ -575,33 +574,60 @@ static int __init dmtimer_clockevent_init(struct device_node *np) */ writel_relaxed(OMAP_TIMER_CTRL_POSTED, t->base + t->ifctrl); + if (dev->cpumask == cpu_possible_mask) + irqflags = IRQF_TIMER; + else + irqflags = IRQF_TIMER | IRQF_NOBALANCING; + error = request_irq(dev->irq, dmtimer_clockevent_interrupt, - IRQF_TIMER, "clockevent", clkevt); + irqflags, name, clkevt); if (error) goto err_out_unmap; writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->irq_ena); writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->wakeup); - pr_info("TI gptimer clockevent: %s%lu Hz at %pOF\n", - of_find_property(np, "ti,timer-alwon", NULL) ? + pr_info("TI gptimer %s: %s%lu Hz at %pOF\n", + name, of_find_property(np, "ti,timer-alwon", NULL) ? "always-on " : "", t->rate, np->parent); - clockevents_config_and_register(dev, t->rate, + return 0; + +err_out_unmap: + iounmap(t->base); + + return error; +} + +static int __init dmtimer_clockevent_init(struct device_node *np) +{ + struct dmtimer_clockevent *clkevt; + int error; + + clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL); + if (!clkevt) + return -ENOMEM; + + error = dmtimer_clkevt_init_common(clkevt, np, + CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT, + cpu_possible_mask, "clockevent", + 300); + if (error) + goto err_out_free; + + clockevents_config_and_register(&clkevt->dev, clkevt->t.rate, 3, /* Timer internal resynch latency */ 0xffffffff); if (of_machine_is_compatible("ti,am33xx") || of_machine_is_compatible("ti,am43")) { - dev->suspend = omap_clockevent_idle; - dev->resume = omap_clockevent_unidle; + clkevt->dev.suspend = omap_clockevent_idle; + clkevt->dev.resume = omap_clockevent_unidle; } return 0; -err_out_unmap: - iounmap(t->base); - err_out_free: kfree(clkevt);