linux/drivers/clocksource/ingenic-timer.c

357 lines
8.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* JZ47xx SoCs TCU IRQ driver
* Copyright (C) 2019 Paul Cercueil <paul@crapouillou.net>
*/
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/interrupt.h>
#include <linux/mfd/ingenic-tcu.h>
#include <linux/mfd/syscon.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/sched_clock.h>
#include <dt-bindings/clock/ingenic,tcu.h>
struct ingenic_soc_info {
unsigned int num_channels;
};
struct ingenic_tcu {
struct regmap *map;
struct clk *timer_clk, *cs_clk;
unsigned int timer_channel, cs_channel;
struct clock_event_device cevt;
struct clocksource cs;
char name[4];
unsigned long pwm_channels_mask;
};
static struct ingenic_tcu *ingenic_tcu;
static u64 notrace ingenic_tcu_timer_read(void)
{
struct ingenic_tcu *tcu = ingenic_tcu;
unsigned int count;
regmap_read(tcu->map, TCU_REG_TCNTc(tcu->cs_channel), &count);
return count;
}
static u64 notrace ingenic_tcu_timer_cs_read(struct clocksource *cs)
{
return ingenic_tcu_timer_read();
}
static inline struct ingenic_tcu *to_ingenic_tcu(struct clock_event_device *evt)
{
return container_of(evt, struct ingenic_tcu, cevt);
}
static int ingenic_tcu_cevt_set_state_shutdown(struct clock_event_device *evt)
{
struct ingenic_tcu *tcu = to_ingenic_tcu(evt);
regmap_write(tcu->map, TCU_REG_TECR, BIT(tcu->timer_channel));
return 0;
}
static int ingenic_tcu_cevt_set_next(unsigned long next,
struct clock_event_device *evt)
{
struct ingenic_tcu *tcu = to_ingenic_tcu(evt);
if (next > 0xffff)
return -EINVAL;
regmap_write(tcu->map, TCU_REG_TDFRc(tcu->timer_channel), next);
regmap_write(tcu->map, TCU_REG_TCNTc(tcu->timer_channel), 0);
regmap_write(tcu->map, TCU_REG_TESR, BIT(tcu->timer_channel));
return 0;
}
static irqreturn_t ingenic_tcu_cevt_cb(int irq, void *dev_id)
{
struct clock_event_device *evt = dev_id;
struct ingenic_tcu *tcu = to_ingenic_tcu(evt);
regmap_write(tcu->map, TCU_REG_TECR, BIT(tcu->timer_channel));
if (evt->event_handler)
evt->event_handler(evt);
return IRQ_HANDLED;
}
static struct clk * __init ingenic_tcu_get_clock(struct device_node *np, int id)
{
struct of_phandle_args args;
args.np = np;
args.args_count = 1;
args.args[0] = id;
return of_clk_get_from_provider(&args);
}
static int __init ingenic_tcu_timer_init(struct device_node *np,
struct ingenic_tcu *tcu)
{
unsigned int timer_virq, channel = tcu->timer_channel;
struct irq_domain *domain;
unsigned long rate;
int err;
tcu->timer_clk = ingenic_tcu_get_clock(np, channel);
if (IS_ERR(tcu->timer_clk))
return PTR_ERR(tcu->timer_clk);
err = clk_prepare_enable(tcu->timer_clk);
if (err)
goto err_clk_put;
rate = clk_get_rate(tcu->timer_clk);
if (!rate) {
err = -EINVAL;
goto err_clk_disable;
}
domain = irq_find_host(np);
if (!domain) {
err = -ENODEV;
goto err_clk_disable;
}
timer_virq = irq_create_mapping(domain, channel);
if (!timer_virq) {
err = -EINVAL;
goto err_clk_disable;
}
snprintf(tcu->name, sizeof(tcu->name), "TCU");
err = request_irq(timer_virq, ingenic_tcu_cevt_cb, IRQF_TIMER,
tcu->name, &tcu->cevt);
if (err)
goto err_irq_dispose_mapping;
tcu->cevt.cpumask = cpumask_of(smp_processor_id());
tcu->cevt.features = CLOCK_EVT_FEAT_ONESHOT;
tcu->cevt.name = tcu->name;
tcu->cevt.rating = 200;
tcu->cevt.set_state_shutdown = ingenic_tcu_cevt_set_state_shutdown;
tcu->cevt.set_next_event = ingenic_tcu_cevt_set_next;
clockevents_config_and_register(&tcu->cevt, rate, 10, 0xffff);
return 0;
err_irq_dispose_mapping:
irq_dispose_mapping(timer_virq);
err_clk_disable:
clk_disable_unprepare(tcu->timer_clk);
err_clk_put:
clk_put(tcu->timer_clk);
return err;
}
static int __init ingenic_tcu_clocksource_init(struct device_node *np,
struct ingenic_tcu *tcu)
{
unsigned int channel = tcu->cs_channel;
struct clocksource *cs = &tcu->cs;
unsigned long rate;
int err;
tcu->cs_clk = ingenic_tcu_get_clock(np, channel);
if (IS_ERR(tcu->cs_clk))
return PTR_ERR(tcu->cs_clk);
err = clk_prepare_enable(tcu->cs_clk);
if (err)
goto err_clk_put;
rate = clk_get_rate(tcu->cs_clk);
if (!rate) {
err = -EINVAL;
goto err_clk_disable;
}
/* Reset channel */
regmap_update_bits(tcu->map, TCU_REG_TCSRc(channel),
0xffff & ~TCU_TCSR_RESERVED_BITS, 0);
/* Reset counter */
regmap_write(tcu->map, TCU_REG_TDFRc(channel), 0xffff);
regmap_write(tcu->map, TCU_REG_TCNTc(channel), 0);
/* Enable channel */
regmap_write(tcu->map, TCU_REG_TESR, BIT(channel));
cs->name = "ingenic-timer";
cs->rating = 200;
cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
cs->mask = CLOCKSOURCE_MASK(16);
cs->read = ingenic_tcu_timer_cs_read;
err = clocksource_register_hz(cs, rate);
if (err)
goto err_clk_disable;
return 0;
err_clk_disable:
clk_disable_unprepare(tcu->cs_clk);
err_clk_put:
clk_put(tcu->cs_clk);
return err;
}
static const struct ingenic_soc_info jz4740_soc_info = {
.num_channels = 8,
};
static const struct ingenic_soc_info jz4725b_soc_info = {
.num_channels = 6,
};
static const struct of_device_id ingenic_tcu_of_match[] = {
{ .compatible = "ingenic,jz4740-tcu", .data = &jz4740_soc_info, },
{ .compatible = "ingenic,jz4725b-tcu", .data = &jz4725b_soc_info, },
{ .compatible = "ingenic,jz4770-tcu", .data = &jz4740_soc_info, },
{ /* sentinel */ }
};
static int __init ingenic_tcu_init(struct device_node *np)
{
const struct of_device_id *id = of_match_node(ingenic_tcu_of_match, np);
const struct ingenic_soc_info *soc_info = id->data;
struct ingenic_tcu *tcu;
struct regmap *map;
long rate;
int ret;
of_node_clear_flag(np, OF_POPULATED);
map = device_node_to_regmap(np);
if (IS_ERR(map))
return PTR_ERR(map);
tcu = kzalloc(sizeof(*tcu), GFP_KERNEL);
if (!tcu)
return -ENOMEM;
/* Enable all TCU channels for PWM use by default except channels 0/1 */
tcu->pwm_channels_mask = GENMASK(soc_info->num_channels - 1, 2);
of_property_read_u32(np, "ingenic,pwm-channels-mask",
(u32 *)&tcu->pwm_channels_mask);
/* Verify that we have at least two free channels */
if (hweight8(tcu->pwm_channels_mask) > soc_info->num_channels - 2) {
pr_crit("%s: Invalid PWM channel mask: 0x%02lx\n", __func__,
tcu->pwm_channels_mask);
ret = -EINVAL;
goto err_free_ingenic_tcu;
}
tcu->map = map;
ingenic_tcu = tcu;
tcu->timer_channel = find_first_zero_bit(&tcu->pwm_channels_mask,
soc_info->num_channels);
tcu->cs_channel = find_next_zero_bit(&tcu->pwm_channels_mask,
soc_info->num_channels,
tcu->timer_channel + 1);
ret = ingenic_tcu_clocksource_init(np, tcu);
if (ret) {
pr_crit("%s: Unable to init clocksource: %d\n", __func__, ret);
goto err_free_ingenic_tcu;
}
ret = ingenic_tcu_timer_init(np, tcu);
if (ret)
goto err_tcu_clocksource_cleanup;
/* Register the sched_clock at the end as there's no way to undo it */
rate = clk_get_rate(tcu->cs_clk);
sched_clock_register(ingenic_tcu_timer_read, 16, rate);
return 0;
err_tcu_clocksource_cleanup:
clocksource_unregister(&tcu->cs);
clk_disable_unprepare(tcu->cs_clk);
clk_put(tcu->cs_clk);
err_free_ingenic_tcu:
kfree(tcu);
return ret;
}
TIMER_OF_DECLARE(jz4740_tcu_intc, "ingenic,jz4740-tcu", ingenic_tcu_init);
TIMER_OF_DECLARE(jz4725b_tcu_intc, "ingenic,jz4725b-tcu", ingenic_tcu_init);
TIMER_OF_DECLARE(jz4770_tcu_intc, "ingenic,jz4770-tcu", ingenic_tcu_init);
static int __init ingenic_tcu_probe(struct platform_device *pdev)
{
platform_set_drvdata(pdev, ingenic_tcu);
return 0;
}
static int __maybe_unused ingenic_tcu_suspend(struct device *dev)
{
struct ingenic_tcu *tcu = dev_get_drvdata(dev);
clk_disable(tcu->cs_clk);
clk_disable(tcu->timer_clk);
return 0;
}
static int __maybe_unused ingenic_tcu_resume(struct device *dev)
{
struct ingenic_tcu *tcu = dev_get_drvdata(dev);
int ret;
ret = clk_enable(tcu->timer_clk);
if (ret)
return ret;
ret = clk_enable(tcu->cs_clk);
if (ret) {
clk_disable(tcu->timer_clk);
return ret;
}
return 0;
}
static const struct dev_pm_ops __maybe_unused ingenic_tcu_pm_ops = {
/* _noirq: We want the TCU clocks to be gated last / ungated first */
.suspend_noirq = ingenic_tcu_suspend,
.resume_noirq = ingenic_tcu_resume,
};
static struct platform_driver ingenic_tcu_driver = {
.driver = {
.name = "ingenic-tcu-timer",
#ifdef CONFIG_PM_SLEEP
.pm = &ingenic_tcu_pm_ops,
#endif
.of_match_table = ingenic_tcu_of_match,
},
};
builtin_platform_driver_probe(ingenic_tcu_driver, ingenic_tcu_probe);