From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964949AbbKCUXS (ORCPT ); Tue, 3 Nov 2015 15:23:18 -0500 Received: from mga03.intel.com ([134.134.136.65]:1240 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964818AbbKCUXL (ORCPT ); Tue, 3 Nov 2015 15:23:11 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,239,1444719600"; d="scan'208";a="677670200" From: Octavian Purdila To: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org, thehajime@gmail.com, Octavian Purdila Subject: [RFC PATCH 09/28] lkl: timers, time and delay support Date: Tue, 3 Nov 2015 22:20:40 +0200 Message-Id: <1446582059-17355-10-git-send-email-octavian.purdila@intel.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1446582059-17355-1-git-send-email-octavian.purdila@intel.com> References: <1446582059-17355-1-git-send-email-octavian.purdila@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Clockevent driver based on host timer operations and clocksource driver and udelay support based on host time operations. Signed-off-by: Octavian Purdila --- arch/lkl/kernel/time.c | 125 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 125 insertions(+) create mode 100644 arch/lkl/kernel/time.c diff --git a/arch/lkl/kernel/time.c b/arch/lkl/kernel/time.c new file mode 100644 index 0000000..d099736 --- /dev/null +++ b/arch/lkl/kernel/time.c @@ -0,0 +1,125 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +void __ndelay(unsigned long nsecs) +{ + unsigned long long start = lkl_ops->time(); + + while (lkl_ops->time() < start + nsecs) + ; +} + +void __udelay(unsigned long usecs) +{ + __ndelay(usecs * NSEC_PER_USEC); +} + +void __const_udelay(unsigned long xloops) +{ + __udelay(xloops / 5); +} + +void calibrate_delay(void) +{ +} + +static cycle_t clock_read(struct clocksource *cs) +{ + return lkl_ops->time(); +} + +static struct clocksource clocksource = { + .name = "lkl", + .rating = 499, + .read = clock_read, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .mask = CLOCKSOURCE_MASK(64), +}; + +static void *timer; + +static int timer_irq; + +static void timer_fn(void *arg) +{ + lkl_trigger_irq(timer_irq, NULL); +} + +static int clockevent_set_state_shutdown(struct clock_event_device *evt) +{ + if (timer) { + lkl_ops->timer_free(timer); + timer = NULL; + } + + return 0; +} + +static int clockevent_set_state_oneshot(struct clock_event_device *evt) +{ + timer = lkl_ops->timer_alloc(timer_fn, NULL); + if (!timer) + return -ENOMEM; + + return 0; +} + +static irqreturn_t timer_irq_handler(int irq, void *dev_id) +{ + struct clock_event_device *dev = (struct clock_event_device *)dev_id; + + dev->event_handler(dev); + + return IRQ_HANDLED; +} + +static int clockevent_next_event(unsigned long hz, + struct clock_event_device *evt) +{ + unsigned long ns = 1000000000 * hz / HZ; + + return lkl_ops->timer_set_oneshot(timer, ns); +} + +static struct clock_event_device clockevent = { + .name = "lkl", + .features = CLOCK_EVT_FEAT_ONESHOT, + .set_state_oneshot = clockevent_set_state_oneshot, + .set_next_event = clockevent_next_event, + .set_state_shutdown = clockevent_set_state_shutdown, +}; + +static struct irqaction irq0 = { + .handler = timer_irq_handler, + .flags = IRQF_NOBALANCING | IRQF_TIMER, + .dev_id = &clockevent, + .name = "timer" +}; + +void __init time_init(void) +{ + int ret; + + if (!lkl_ops->timer_alloc || !lkl_ops->timer_free || + !lkl_ops->timer_set_oneshot || !lkl_ops->time) { + pr_err("lkl: no time or timer support provided by host\n"); + return; + } + + timer_irq = lkl_get_free_irq("timer"); + setup_irq(timer_irq, &irq0); + + ret = clocksource_register_khz(&clocksource, 1000000); + if (ret) + pr_err("lkl: unable to register clocksource\n"); + + clockevents_config_and_register(&clockevent, HZ, 0, 0xffffffff); + + pr_info("lkl: time and timers initialized\n"); +} -- 2.1.0