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![Daniel Lezcano](/assets/img/avatar_default.png)
All the clocksource drivers's init function are now converted to return an error code. CLOCKSOURCE_OF_DECLARE is no longer used as well as the clksrc-of table. Let's convert back the names: - CLOCKSOURCE_OF_DECLARE_RET => CLOCKSOURCE_OF_DECLARE - clksrc-of-ret => clksrc-of Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> For exynos_mct and samsung_pwm_timer: Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> For arch/arc: Acked-by: Vineet Gupta <vgupta@synopsys.com> For mediatek driver: Acked-by: Matthias Brugger <matthias.bgg@gmail.com> For the Rockchip-part Acked-by: Heiko Stuebner <heiko@sntech.de> For STi : Acked-by: Patrice Chotard <patrice.chotard@st.com> For the mps2-timer.c and versatile.c changes: Acked-by: Liviu Dudau <Liviu.Dudau@arm.com> For the OXNAS part : Acked-by: Neil Armstrong <narmstrong@baylibre.com> For LPC32xx driver: Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com> For Broadcom Kona timer change: Acked-by: Ray Jui <ray.jui@broadcom.com> For Sun4i and Sun5i: Acked-by: Chen-Yu Tsai <wens@csie.org> For Meson6: Acked-by: Carlo Caione <carlo@caione.org> For Keystone: Acked-by: Santosh Shilimkar <ssantosh@kernel.org> For NPS: Acked-by: Noam Camus <noamca@mellanox.com> For bcm2835: Acked-by: Eric Anholt <eric@anholt.net>
146 lines
3.8 KiB
C
146 lines
3.8 KiB
C
/*
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* Copyright 2012 Simon Arlott
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/bitops.h>
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#include <linux/clockchips.h>
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#include <linux/clocksource.h>
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#include <linux/interrupt.h>
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#include <linux/irqreturn.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/of_address.h>
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#include <linux/of_irq.h>
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#include <linux/of_platform.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/sched_clock.h>
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#include <asm/irq.h>
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#define REG_CONTROL 0x00
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#define REG_COUNTER_LO 0x04
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#define REG_COUNTER_HI 0x08
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#define REG_COMPARE(n) (0x0c + (n) * 4)
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#define MAX_TIMER 3
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#define DEFAULT_TIMER 3
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struct bcm2835_timer {
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void __iomem *control;
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void __iomem *compare;
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int match_mask;
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struct clock_event_device evt;
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struct irqaction act;
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};
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static void __iomem *system_clock __read_mostly;
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static u64 notrace bcm2835_sched_read(void)
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{
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return readl_relaxed(system_clock);
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}
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static int bcm2835_time_set_next_event(unsigned long event,
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struct clock_event_device *evt_dev)
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{
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struct bcm2835_timer *timer = container_of(evt_dev,
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struct bcm2835_timer, evt);
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writel_relaxed(readl_relaxed(system_clock) + event,
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timer->compare);
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return 0;
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}
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static irqreturn_t bcm2835_time_interrupt(int irq, void *dev_id)
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{
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struct bcm2835_timer *timer = dev_id;
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void (*event_handler)(struct clock_event_device *);
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if (readl_relaxed(timer->control) & timer->match_mask) {
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writel_relaxed(timer->match_mask, timer->control);
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event_handler = ACCESS_ONCE(timer->evt.event_handler);
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if (event_handler)
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event_handler(&timer->evt);
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return IRQ_HANDLED;
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} else {
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return IRQ_NONE;
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}
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}
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static int __init bcm2835_timer_init(struct device_node *node)
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{
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void __iomem *base;
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u32 freq;
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int irq, ret;
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struct bcm2835_timer *timer;
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base = of_iomap(node, 0);
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if (!base) {
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pr_err("Can't remap registers");
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return -ENXIO;
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}
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ret = of_property_read_u32(node, "clock-frequency", &freq);
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if (ret) {
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pr_err("Can't read clock-frequency");
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return ret;
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}
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system_clock = base + REG_COUNTER_LO;
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sched_clock_register(bcm2835_sched_read, 32, freq);
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clocksource_mmio_init(base + REG_COUNTER_LO, node->name,
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freq, 300, 32, clocksource_mmio_readl_up);
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irq = irq_of_parse_and_map(node, DEFAULT_TIMER);
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if (irq <= 0) {
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pr_err("Can't parse IRQ");
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return -EINVAL;
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}
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timer = kzalloc(sizeof(*timer), GFP_KERNEL);
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if (!timer) {
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pr_err("Can't allocate timer struct\n");
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return -ENOMEM;
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}
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timer->control = base + REG_CONTROL;
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timer->compare = base + REG_COMPARE(DEFAULT_TIMER);
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timer->match_mask = BIT(DEFAULT_TIMER);
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timer->evt.name = node->name;
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timer->evt.rating = 300;
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timer->evt.features = CLOCK_EVT_FEAT_ONESHOT;
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timer->evt.set_next_event = bcm2835_time_set_next_event;
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timer->evt.cpumask = cpumask_of(0);
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timer->act.name = node->name;
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timer->act.flags = IRQF_TIMER | IRQF_SHARED;
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timer->act.dev_id = timer;
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timer->act.handler = bcm2835_time_interrupt;
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ret = setup_irq(irq, &timer->act);
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if (ret) {
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pr_err("Can't set up timer IRQ\n");
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return ret;
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}
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clockevents_config_and_register(&timer->evt, freq, 0xf, 0xffffffff);
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pr_info("bcm2835: system timer (irq = %d)\n", irq);
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return 0;
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}
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CLOCKSOURCE_OF_DECLARE(bcm2835, "brcm,bcm2835-system-timer",
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bcm2835_timer_init);
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