forked from luck/tmp_suning_uos_patched
effbfdd7ba
In cases where we have multiple nodes of the same type, we may need the node pointer to know which node was matched. Passing the node pointer also keeps the init function from having to match the node a 2nd time. Update bcm2835, vt8500, and tegra20 init functions for the new function prototype. Further tegra20 clean-ups are in follow-up commit. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Cc: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Stephen Warren <swarren@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Tony Prisk <linux@prisktech.co.nz> Tested-by: Michal Simek <michal.simek@xilinx.com>
169 lines
4.8 KiB
C
169 lines
4.8 KiB
C
/*
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* arch/arm/mach-vt8500/timer.c
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*
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* Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz>
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* Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
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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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/*
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* This file is copied and modified from the original timer.c provided by
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* Alexey Charkov. Minor changes have been made for Device Tree Support.
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*/
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#include <linux/io.h>
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#include <linux/irq.h>
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#include <linux/interrupt.h>
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#include <linux/clocksource.h>
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#include <linux/clockchips.h>
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#include <linux/delay.h>
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#include <asm/mach/time.h>
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#include <linux/of.h>
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#include <linux/of_address.h>
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#include <linux/of_irq.h>
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#define VT8500_TIMER_OFFSET 0x0100
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#define VT8500_TIMER_HZ 3000000
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#define TIMER_MATCH_VAL 0x0000
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#define TIMER_COUNT_VAL 0x0010
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#define TIMER_STATUS_VAL 0x0014
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#define TIMER_IER_VAL 0x001c /* interrupt enable */
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#define TIMER_CTRL_VAL 0x0020
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#define TIMER_AS_VAL 0x0024 /* access status */
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#define TIMER_COUNT_R_ACTIVE (1 << 5) /* not ready for read */
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#define TIMER_COUNT_W_ACTIVE (1 << 4) /* not ready for write */
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#define TIMER_MATCH_W_ACTIVE (1 << 0) /* not ready for write */
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#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
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static void __iomem *regbase;
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static cycle_t vt8500_timer_read(struct clocksource *cs)
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{
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int loops = msecs_to_loops(10);
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writel(3, regbase + TIMER_CTRL_VAL);
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while ((readl((regbase + TIMER_AS_VAL)) & TIMER_COUNT_R_ACTIVE)
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&& --loops)
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cpu_relax();
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return readl(regbase + TIMER_COUNT_VAL);
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}
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static struct clocksource clocksource = {
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.name = "vt8500_timer",
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.rating = 200,
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.read = vt8500_timer_read,
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.mask = CLOCKSOURCE_MASK(32),
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.flags = CLOCK_SOURCE_IS_CONTINUOUS,
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};
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static int vt8500_timer_set_next_event(unsigned long cycles,
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struct clock_event_device *evt)
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{
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int loops = msecs_to_loops(10);
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cycle_t alarm = clocksource.read(&clocksource) + cycles;
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while ((readl(regbase + TIMER_AS_VAL) & TIMER_MATCH_W_ACTIVE)
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&& --loops)
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cpu_relax();
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writel((unsigned long)alarm, regbase + TIMER_MATCH_VAL);
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if ((signed)(alarm - clocksource.read(&clocksource)) <= 16)
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return -ETIME;
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writel(1, regbase + TIMER_IER_VAL);
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return 0;
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}
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static void vt8500_timer_set_mode(enum clock_event_mode mode,
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struct clock_event_device *evt)
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{
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switch (mode) {
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case CLOCK_EVT_MODE_RESUME:
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case CLOCK_EVT_MODE_PERIODIC:
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break;
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case CLOCK_EVT_MODE_ONESHOT:
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case CLOCK_EVT_MODE_UNUSED:
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case CLOCK_EVT_MODE_SHUTDOWN:
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writel(readl(regbase + TIMER_CTRL_VAL) | 1,
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regbase + TIMER_CTRL_VAL);
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writel(0, regbase + TIMER_IER_VAL);
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break;
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}
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}
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static struct clock_event_device clockevent = {
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.name = "vt8500_timer",
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.features = CLOCK_EVT_FEAT_ONESHOT,
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.rating = 200,
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.set_next_event = vt8500_timer_set_next_event,
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.set_mode = vt8500_timer_set_mode,
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};
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static irqreturn_t vt8500_timer_interrupt(int irq, void *dev_id)
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{
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struct clock_event_device *evt = dev_id;
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writel(0xf, regbase + TIMER_STATUS_VAL);
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evt->event_handler(evt);
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return IRQ_HANDLED;
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}
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static struct irqaction irq = {
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.name = "vt8500_timer",
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.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
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.handler = vt8500_timer_interrupt,
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.dev_id = &clockevent,
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};
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static void __init vt8500_timer_init(struct device_node *np)
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{
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int timer_irq;
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regbase = of_iomap(np, 0);
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if (!regbase) {
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pr_err("%s: Missing iobase description in Device Tree\n",
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__func__);
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of_node_put(np);
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return;
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}
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timer_irq = irq_of_parse_and_map(np, 0);
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if (!timer_irq) {
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pr_err("%s: Missing irq description in Device Tree\n",
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__func__);
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of_node_put(np);
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return;
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}
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writel(1, regbase + TIMER_CTRL_VAL);
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writel(0xf, regbase + TIMER_STATUS_VAL);
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writel(~0, regbase + TIMER_MATCH_VAL);
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if (clocksource_register_hz(&clocksource, VT8500_TIMER_HZ))
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pr_err("%s: vt8500_timer_init: clocksource_register failed for %s\n",
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__func__, clocksource.name);
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clockevent.cpumask = cpumask_of(0);
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if (setup_irq(timer_irq, &irq))
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pr_err("%s: setup_irq failed for %s\n", __func__,
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clockevent.name);
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clockevents_config_and_register(&clockevent, VT8500_TIMER_HZ,
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4, 0xf0000000);
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}
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CLOCKSOURCE_OF_DECLARE(vt8500, "via,vt8500-timer", vt8500_timer_init)
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