From: Olof Johansson Date: Mon, 14 Jan 2013 22:13:40 +0000 (-0800) Subject: Merge tag 'vt8500/timer' of git://server.prisktech.co.nz/git/linuxwmt into next/cleanup X-Git-Tag: firefly_0821_release~3680^2~1075^2~28 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=175dbc1eeadbdcf5f04d3a61fdc0ede4335c45c8;p=firefly-linux-kernel-4.4.55.git Merge tag 'vt8500/timer' of git://server.prisktech.co.nz/git/linuxwmt into next/cleanup From Tony Prisk: Move arch-vt8500/timer.c to drivers/clocksource/vt8500-timer.c * tag 'vt8500/timer' of git://server.prisktech.co.nz/git/linuxwmt: timer: vt8500: Move timer code to drivers/clocksource Signed-off-by: Olof Johansson --- 175dbc1eeadbdcf5f04d3a61fdc0ede4335c45c8 diff --cc drivers/clocksource/vt8500_timer.c index 000000000000,3dd21a47881f..ed66cf07d3c6 mode 000000,100644..100644 --- a/drivers/clocksource/vt8500_timer.c +++ b/drivers/clocksource/vt8500_timer.c @@@ -1,0 -1,184 +1,179 @@@ + /* + * arch/arm/mach-vt8500/timer.c + * + * Copyright (C) 2012 Tony Prisk + * Copyright (C) 2010 Alexey Charkov + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + + /* + * This file is copied and modified from the original timer.c provided by + * Alexey Charkov. Minor changes have been made for Device Tree Support. + */ + + #include + #include + #include + #include + #include + #include + #include + + #include + #include + #include + + #define VT8500_TIMER_OFFSET 0x0100 + #define VT8500_TIMER_HZ 3000000 + #define TIMER_MATCH_VAL 0x0000 + #define TIMER_COUNT_VAL 0x0010 + #define TIMER_STATUS_VAL 0x0014 + #define TIMER_IER_VAL 0x001c /* interrupt enable */ + #define TIMER_CTRL_VAL 0x0020 + #define TIMER_AS_VAL 0x0024 /* access status */ + #define TIMER_COUNT_R_ACTIVE (1 << 5) /* not ready for read */ + #define TIMER_COUNT_W_ACTIVE (1 << 4) /* not ready for write */ + #define TIMER_MATCH_W_ACTIVE (1 << 0) /* not ready for write */ + + #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t) + + static void __iomem *regbase; + + static cycle_t vt8500_timer_read(struct clocksource *cs) + { + int loops = msecs_to_loops(10); + writel(3, regbase + TIMER_CTRL_VAL); + while ((readl((regbase + TIMER_AS_VAL)) & TIMER_COUNT_R_ACTIVE) + && --loops) + cpu_relax(); + return readl(regbase + TIMER_COUNT_VAL); + } + + static struct clocksource clocksource = { + .name = "vt8500_timer", + .rating = 200, + .read = vt8500_timer_read, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + }; + + static int vt8500_timer_set_next_event(unsigned long cycles, + struct clock_event_device *evt) + { + int loops = msecs_to_loops(10); + cycle_t alarm = clocksource.read(&clocksource) + cycles; + while ((readl(regbase + TIMER_AS_VAL) & TIMER_MATCH_W_ACTIVE) + && --loops) + cpu_relax(); + writel((unsigned long)alarm, regbase + TIMER_MATCH_VAL); + + if ((signed)(alarm - clocksource.read(&clocksource)) <= 16) + return -ETIME; + + writel(1, regbase + TIMER_IER_VAL); + + return 0; + } + + static void vt8500_timer_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) + { + switch (mode) { + case CLOCK_EVT_MODE_RESUME: + case CLOCK_EVT_MODE_PERIODIC: + break; + case CLOCK_EVT_MODE_ONESHOT: + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + writel(readl(regbase + TIMER_CTRL_VAL) | 1, + regbase + TIMER_CTRL_VAL); + writel(0, regbase + TIMER_IER_VAL); + break; + } + } + + static struct clock_event_device clockevent = { + .name = "vt8500_timer", + .features = CLOCK_EVT_FEAT_ONESHOT, + .rating = 200, + .set_next_event = vt8500_timer_set_next_event, + .set_mode = vt8500_timer_set_mode, + }; + + static irqreturn_t vt8500_timer_interrupt(int irq, void *dev_id) + { + struct clock_event_device *evt = dev_id; + writel(0xf, regbase + TIMER_STATUS_VAL); + evt->event_handler(evt); + + return IRQ_HANDLED; + } + + static struct irqaction irq = { + .name = "vt8500_timer", + .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, + .handler = vt8500_timer_interrupt, + .dev_id = &clockevent, + }; + + static struct of_device_id vt8500_timer_ids[] = { + { .compatible = "via,vt8500-timer" }, + { } + }; + + void __init vt8500_timer_init(void) + { + struct device_node *np; + int timer_irq; + + np = of_find_matching_node(NULL, vt8500_timer_ids); + if (!np) { + pr_err("%s: Timer description missing from Device Tree\n", + __func__); + return; + } + regbase = of_iomap(np, 0); + if (!regbase) { + pr_err("%s: Missing iobase description in Device Tree\n", + __func__); + of_node_put(np); + return; + } + timer_irq = irq_of_parse_and_map(np, 0); + if (!timer_irq) { + pr_err("%s: Missing irq description in Device Tree\n", + __func__); + of_node_put(np); + return; + } + + writel(1, regbase + TIMER_CTRL_VAL); + writel(0xf, regbase + TIMER_STATUS_VAL); + writel(~0, regbase + TIMER_MATCH_VAL); + + if (clocksource_register_hz(&clocksource, VT8500_TIMER_HZ)) + pr_err("%s: vt8500_timer_init: clocksource_register failed for %s\n", + __func__, clocksource.name); + - clockevents_calc_mult_shift(&clockevent, VT8500_TIMER_HZ, 4); - - /* copy-pasted from mach-msm; no idea */ - clockevent.max_delta_ns = - clockevent_delta2ns(0xf0000000, &clockevent); - clockevent.min_delta_ns = clockevent_delta2ns(4, &clockevent); + clockevent.cpumask = cpumask_of(0); + + if (setup_irq(timer_irq, &irq)) + pr_err("%s: setup_irq failed for %s\n", __func__, + clockevent.name); - clockevents_register_device(&clockevent); ++ clockevents_config_and_register(&clockevent, VT8500_TIMER_HZ, ++ 4, 0xf0000000); + } +