Files
linux-stable-mirror/drivers/clocksource/bcm2835_timer.c
Linus Torvalds bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00

138 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2012 Simon Arlott
*/
#include <linux/bitops.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/interrupt.h>
#include <linux/irqreturn.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/sched_clock.h>
#include <asm/irq.h>
#define REG_CONTROL 0x00
#define REG_COUNTER_LO 0x04
#define REG_COUNTER_HI 0x08
#define REG_COMPARE(n) (0x0c + (n) * 4)
#define MAX_TIMER 3
#define DEFAULT_TIMER 3
struct bcm2835_timer {
void __iomem *control;
void __iomem *compare;
int match_mask;
struct clock_event_device evt;
};
static void __iomem *system_clock __read_mostly;
static u64 notrace bcm2835_sched_read(void)
{
return readl_relaxed(system_clock);
}
static int bcm2835_time_set_next_event(unsigned long event,
struct clock_event_device *evt_dev)
{
struct bcm2835_timer *timer = container_of(evt_dev,
struct bcm2835_timer, evt);
writel_relaxed(readl_relaxed(system_clock) + event,
timer->compare);
return 0;
}
static irqreturn_t bcm2835_time_interrupt(int irq, void *dev_id)
{
struct bcm2835_timer *timer = dev_id;
void (*event_handler)(struct clock_event_device *);
if (readl_relaxed(timer->control) & timer->match_mask) {
writel_relaxed(timer->match_mask, timer->control);
event_handler = READ_ONCE(timer->evt.event_handler);
if (event_handler)
event_handler(&timer->evt);
return IRQ_HANDLED;
} else {
return IRQ_NONE;
}
}
static int __init bcm2835_timer_init(struct device_node *node)
{
void __iomem *base;
u32 freq;
int irq, ret;
struct bcm2835_timer *timer;
base = of_iomap(node, 0);
if (!base) {
pr_err("Can't remap registers\n");
return -ENXIO;
}
ret = of_property_read_u32(node, "clock-frequency", &freq);
if (ret) {
pr_err("Can't read clock-frequency\n");
goto err_iounmap;
}
system_clock = base + REG_COUNTER_LO;
sched_clock_register(bcm2835_sched_read, 32, freq);
clocksource_mmio_init(base + REG_COUNTER_LO, node->name,
freq, 300, 32, clocksource_mmio_readl_up);
irq = irq_of_parse_and_map(node, DEFAULT_TIMER);
if (irq <= 0) {
pr_err("Can't parse IRQ\n");
ret = -EINVAL;
goto err_iounmap;
}
timer = kzalloc_obj(*timer);
if (!timer) {
ret = -ENOMEM;
goto err_iounmap;
}
timer->control = base + REG_CONTROL;
timer->compare = base + REG_COMPARE(DEFAULT_TIMER);
timer->match_mask = BIT(DEFAULT_TIMER);
timer->evt.name = node->name;
timer->evt.rating = 300;
timer->evt.features = CLOCK_EVT_FEAT_ONESHOT;
timer->evt.set_next_event = bcm2835_time_set_next_event;
timer->evt.cpumask = cpumask_of(0);
ret = request_irq(irq, bcm2835_time_interrupt, IRQF_TIMER | IRQF_SHARED,
node->name, timer);
if (ret) {
pr_err("Can't set up timer IRQ\n");
goto err_timer_free;
}
clockevents_config_and_register(&timer->evt, freq, 0xf, 0xffffffff);
pr_info("bcm2835: system timer (irq = %d)\n", irq);
return 0;
err_timer_free:
kfree(timer);
err_iounmap:
iounmap(base);
return ret;
}
TIMER_OF_DECLARE(bcm2835, "brcm,bcm2835-system-timer",
bcm2835_timer_init);