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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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6303d0693f
The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it was merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Link: https://lore.kernel.org/r/20230714174409.4053843-1-robh@kernel.org Signed-off-by: Rob Herring <robh@kernel.org>
137 lines
3.1 KiB
C
137 lines
3.1 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* Copyright 2012 Simon Arlott
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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.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/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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};
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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 = READ_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\n");
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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\n");
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goto err_iounmap;
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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\n");
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ret = -EINVAL;
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goto err_iounmap;
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}
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timer = kzalloc(sizeof(*timer), GFP_KERNEL);
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if (!timer) {
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ret = -ENOMEM;
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goto err_iounmap;
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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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ret = request_irq(irq, bcm2835_time_interrupt, IRQF_TIMER | IRQF_SHARED,
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node->name, timer);
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if (ret) {
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pr_err("Can't set up timer IRQ\n");
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goto err_timer_free;
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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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err_timer_free:
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kfree(timer);
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err_iounmap:
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iounmap(base);
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return ret;
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}
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TIMER_OF_DECLARE(bcm2835, "brcm,bcm2835-system-timer",
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bcm2835_timer_init);
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