clocksource: Add JH7110 timer driver

Add timer driver for the StarFive JH7110 SoC.

Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
This commit is contained in:
Xingyu Wu 2023-10-19 13:35:00 +08:00 committed by Hal Feng
parent 0b415975de
commit a388fc116a
3 changed files with 392 additions and 0 deletions

View file

@ -641,6 +641,17 @@ config RISCV_TIMER
is accessed via both the SBI and the rdcycle instruction. This is
required for all RISC-V systems.
config STARFIVE_JH7110_TIMER
bool "Timer for the STARFIVE JH7110 SoC"
depends on ARCH_STARFIVE || COMPILE_TEST
select TIMER_OF
select CLKSRC_MMIO
default ARCH_STARFIVE
help
This enables the timer for StarFive JH7110 SoC. On RISC-V platform,
the system has started RISCV_TIMER, but you can also use this timer
which can provide four channels to do a lot more things on JH7110 SoC.
config CLINT_TIMER
bool "CLINT Timer for the RISC-V platform" if COMPILE_TEST
depends on GENERIC_SCHED_CLOCK && RISCV

View file

@ -80,6 +80,7 @@ obj-$(CONFIG_INGENIC_TIMER) += ingenic-timer.o
obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o
obj-$(CONFIG_X86_NUMACHIP) += numachip.o
obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o
obj-$(CONFIG_STARFIVE_JH7110_TIMER) += timer-jh7110.o
obj-$(CONFIG_CLINT_TIMER) += timer-clint.o
obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o
obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o

View file

@ -0,0 +1,380 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Starfive JH7110 Timer driver
*
* Copyright (C) 2022-2023 StarFive Technology Co., Ltd.
*
* Author:
* Xingyu Wu <xingyu.wu@starfivetech.com>
* Samin Guo <samin.guo@starfivetech.com>
*/
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/sched_clock.h>
/* Bias: Ch0-0x0, Ch1-0x40, Ch2-0x80, and so on. */
#define JH7110_TIMER_CH_LEN 0x40
#define JH7110_TIMER_CH_BASE(x) ((x) * JH7110_TIMER_CH_LEN)
#define JH7110_TIMER_CH_MAX 4
#define JH7110_CLOCK_SOURCE_RATING 200
#define JH7110_VALID_BITS 32
#define JH7110_DELAY_US 0
#define JH7110_TIMEOUT_US 10000
#define JH7110_CLOCKEVENT_RATING 300
#define JH7110_TIMER_MAX_TICKS 0xffffffff
#define JH7110_TIMER_MIN_TICKS 0xf
#define JH7110_TIMER_RELOAD_VALUE 0
#define JH7110_TIMER_INT_STATUS 0x00 /* RO[0:4]: Interrupt Status for channel0~4 */
#define JH7110_TIMER_CTL 0x04 /* RW[0]: 0-continuous run, 1-single run */
#define JH7110_TIMER_LOAD 0x08 /* RW: load value to counter */
#define JH7110_TIMER_ENABLE 0x10 /* RW[0]: timer enable register */
#define JH7110_TIMER_RELOAD 0x14 /* RW: write 1 or 0 both reload counter */
#define JH7110_TIMER_VALUE 0x18 /* RO: timer value register */
#define JH7110_TIMER_INT_CLR 0x20 /* RW: timer interrupt clear register */
#define JH7110_TIMER_INT_MASK 0x24 /* RW[0]: timer interrupt mask register */
#define JH7110_TIMER_INT_CLR_ENA BIT(0)
#define JH7110_TIMER_INT_CLR_AVA_MASK BIT(1)
struct jh7110_clkevt {
struct clock_event_device evt;
struct clocksource cs;
bool cs_is_valid;
struct clk *clk;
struct reset_control *rst;
u32 rate;
u32 reload_val;
void __iomem *base;
char name[sizeof("jh7110-timer.chX")];
};
struct jh7110_timer_priv {
struct clk *pclk;
struct reset_control *prst;
struct jh7110_clkevt clkevt[JH7110_TIMER_CH_MAX];
};
/* 0:continuous-run mode, 1:single-run mode */
enum jh7110_timer_mode {
JH7110_TIMER_MODE_CONTIN,
JH7110_TIMER_MODE_SINGLE,
};
/* Interrupt Mask, 0:Unmask, 1:Mask */
enum jh7110_timer_int_mask {
JH7110_TIMER_INT_ENA,
JH7110_TIMER_INT_DIS,
};
enum jh7110_timer_enable {
JH7110_TIMER_DIS,
JH7110_TIMER_ENA,
};
static inline struct jh7110_clkevt *to_jh7110_clkevt(struct clock_event_device *evt)
{
return container_of(evt, struct jh7110_clkevt, evt);
}
/*
* BIT(0): Read value represent channel int status.
* Write 1 to this bit to clear interrupt. Write 0 has no effects.
* BIT(1): "1" means that it is clearing interrupt. BIT(0) can not be written.
*/
static inline int jh7110_timer_int_clear(struct jh7110_clkevt *clkevt)
{
u32 value;
int ret;
/* Waiting interrupt can be cleared */
ret = readl_poll_timeout_atomic(clkevt->base + JH7110_TIMER_INT_CLR, value,
!(value & JH7110_TIMER_INT_CLR_AVA_MASK),
JH7110_DELAY_US, JH7110_TIMEOUT_US);
if (!ret)
writel(JH7110_TIMER_INT_CLR_ENA, clkevt->base + JH7110_TIMER_INT_CLR);
return ret;
}
static int jh7110_timer_start(struct jh7110_clkevt *clkevt)
{
int ret;
/* Disable and clear interrupt first */
writel(JH7110_TIMER_INT_DIS, clkevt->base + JH7110_TIMER_INT_MASK);
ret = jh7110_timer_int_clear(clkevt);
if (ret)
return ret;
writel(JH7110_TIMER_INT_ENA, clkevt->base + JH7110_TIMER_INT_MASK);
writel(JH7110_TIMER_ENA, clkevt->base + JH7110_TIMER_ENABLE);
return 0;
}
static int jh7110_timer_shutdown(struct clock_event_device *evt)
{
struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt);
writel(JH7110_TIMER_DIS, clkevt->base + JH7110_TIMER_ENABLE);
return jh7110_timer_int_clear(clkevt);
}
static void jh7110_timer_suspend(struct clock_event_device *evt)
{
struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt);
clkevt->reload_val = readl(clkevt->base + JH7110_TIMER_LOAD);
jh7110_timer_shutdown(evt);
}
static void jh7110_timer_resume(struct clock_event_device *evt)
{
struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt);
writel(clkevt->reload_val, clkevt->base + JH7110_TIMER_LOAD);
writel(JH7110_TIMER_RELOAD_VALUE, clkevt->base + JH7110_TIMER_RELOAD);
jh7110_timer_start(clkevt);
}
static int jh7110_timer_tick_resume(struct clock_event_device *evt)
{
jh7110_timer_resume(evt);
return 0;
}
/* IRQ handler for the timer */
static irqreturn_t jh7110_timer_interrupt(int irq, void *priv)
{
struct clock_event_device *evt = (struct clock_event_device *)priv;
struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt);
if (jh7110_timer_int_clear(clkevt))
return IRQ_NONE;
if (evt->event_handler)
evt->event_handler(evt);
return IRQ_HANDLED;
}
static int jh7110_timer_set_periodic(struct clock_event_device *evt)
{
struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt);
u32 periodic = DIV_ROUND_CLOSEST(clkevt->rate, HZ);
writel(JH7110_TIMER_MODE_CONTIN, clkevt->base + JH7110_TIMER_CTL);
writel(periodic, clkevt->base + JH7110_TIMER_LOAD);
return jh7110_timer_start(clkevt);
}
static int jh7110_timer_set_oneshot(struct clock_event_device *evt)
{
struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt);
writel(JH7110_TIMER_MODE_SINGLE, clkevt->base + JH7110_TIMER_CTL);
writel(JH7110_TIMER_MAX_TICKS, clkevt->base + JH7110_TIMER_LOAD);
return jh7110_timer_start(clkevt);
}
static int jh7110_timer_set_next_event(unsigned long next,
struct clock_event_device *evt)
{
struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt);
writel(JH7110_TIMER_MODE_SINGLE, clkevt->base + JH7110_TIMER_CTL);
writel(next, clkevt->base + JH7110_TIMER_LOAD);
return jh7110_timer_start(clkevt);
}
static void jh7110_set_clockevent(struct clock_event_device *evt)
{
evt->features = CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_FEAT_ONESHOT |
CLOCK_EVT_FEAT_DYNIRQ;
evt->set_state_shutdown = jh7110_timer_shutdown;
evt->set_state_periodic = jh7110_timer_set_periodic;
evt->set_state_oneshot = jh7110_timer_set_oneshot;
evt->set_state_oneshot_stopped = jh7110_timer_shutdown;
evt->tick_resume = jh7110_timer_tick_resume;
evt->set_next_event = jh7110_timer_set_next_event;
evt->suspend = jh7110_timer_suspend;
evt->resume = jh7110_timer_resume;
evt->rating = JH7110_CLOCKEVENT_RATING;
}
static u64 jh7110_timer_clocksource_read(struct clocksource *cs)
{
struct jh7110_clkevt *clkevt = container_of(cs, struct jh7110_clkevt, cs);
return (u64)readl(clkevt->base + JH7110_TIMER_VALUE);
}
static int jh7110_clocksource_init(struct jh7110_clkevt *clkevt)
{
int ret;
clkevt->cs.name = clkevt->name;
clkevt->cs.rating = JH7110_CLOCK_SOURCE_RATING;
clkevt->cs.read = jh7110_timer_clocksource_read;
clkevt->cs.mask = CLOCKSOURCE_MASK(JH7110_VALID_BITS);
clkevt->cs.flags = CLOCK_SOURCE_IS_CONTINUOUS;
ret = clocksource_register_hz(&clkevt->cs, clkevt->rate);
if (ret)
return ret;
clkevt->cs_is_valid = true; /* clocksource register done */
writel(JH7110_TIMER_MODE_CONTIN, clkevt->base + JH7110_TIMER_CTL);
writel(JH7110_TIMER_MAX_TICKS, clkevt->base + JH7110_TIMER_LOAD);
return jh7110_timer_start(clkevt);
}
static void jh7110_clockevents_register(struct jh7110_clkevt *clkevt)
{
clkevt->rate = clk_get_rate(clkevt->clk);
jh7110_set_clockevent(&clkevt->evt);
clkevt->evt.name = clkevt->name;
clkevt->evt.cpumask = cpu_possible_mask;
clockevents_config_and_register(&clkevt->evt, clkevt->rate,
JH7110_TIMER_MIN_TICKS, JH7110_TIMER_MAX_TICKS);
}
static void jh7110_timer_release(void *data)
{
struct jh7110_timer_priv *priv = data;
int i;
for (i = 0; i < JH7110_TIMER_CH_MAX; i++) {
/* Disable each channel of timer */
if (priv->clkevt[i].base)
writel(JH7110_TIMER_DIS, priv->clkevt[i].base + JH7110_TIMER_ENABLE);
/* Avoid no initialization in the loop of the probe */
if (!IS_ERR_OR_NULL(priv->clkevt[i].rst))
reset_control_assert(priv->clkevt[i].rst);
if (priv->clkevt[i].cs_is_valid)
clocksource_unregister(&priv->clkevt[i].cs);
}
reset_control_assert(priv->prst);
}
static int jh7110_timer_probe(struct platform_device *pdev)
{
struct jh7110_timer_priv *priv;
struct jh7110_clkevt *clkevt;
char name[sizeof("chX")];
int ch;
int ret;
void __iomem *base;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(base))
return dev_err_probe(&pdev->dev, PTR_ERR(base),
"failed to map registers\n");
priv->prst = devm_reset_control_get_exclusive(&pdev->dev, "apb");
if (IS_ERR(priv->prst))
return dev_err_probe(&pdev->dev, PTR_ERR(priv->prst),
"failed to get apb reset\n");
priv->pclk = devm_clk_get_enabled(&pdev->dev, "apb");
if (IS_ERR(priv->pclk))
return dev_err_probe(&pdev->dev, PTR_ERR(priv->pclk),
"failed to get & enable apb clock\n");
ret = reset_control_deassert(priv->prst);
if (ret)
return dev_err_probe(&pdev->dev, ret, "failed to deassert apb reset\n");
ret = devm_add_action_or_reset(&pdev->dev, jh7110_timer_release, priv);
if (ret)
return ret;
for (ch = 0; ch < JH7110_TIMER_CH_MAX; ch++) {
clkevt = &priv->clkevt[ch];
snprintf(name, sizeof(name), "ch%d", ch);
clkevt->base = base + JH7110_TIMER_CH_BASE(ch);
/* Ensure timer is disabled */
writel(JH7110_TIMER_DIS, clkevt->base + JH7110_TIMER_ENABLE);
clkevt->rst = devm_reset_control_get_exclusive(&pdev->dev, name);
if (IS_ERR(clkevt->rst))
return PTR_ERR(clkevt->rst);
clkevt->clk = devm_clk_get_enabled(&pdev->dev, name);
if (IS_ERR(clkevt->clk))
return PTR_ERR(clkevt->clk);
ret = reset_control_deassert(clkevt->rst);
if (ret)
return ret;
clkevt->evt.irq = platform_get_irq(pdev, ch);
if (clkevt->evt.irq < 0)
return clkevt->evt.irq;
snprintf(clkevt->name, sizeof(clkevt->name), "jh7110-timer.ch%d", ch);
jh7110_clockevents_register(clkevt);
ret = devm_request_irq(&pdev->dev, clkevt->evt.irq, jh7110_timer_interrupt,
IRQF_TIMER | IRQF_IRQPOLL,
clkevt->name, &clkevt->evt);
if (ret)
return ret;
ret = jh7110_clocksource_init(clkevt);
if (ret)
return ret;
}
return 0;
}
static const struct of_device_id jh7110_timer_match[] = {
{ .compatible = "starfive,jh7110-timer", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, jh7110_timer_match);
static struct platform_driver jh7110_timer_driver = {
.probe = jh7110_timer_probe,
.driver = {
.name = "jh7110-timer",
.of_match_table = jh7110_timer_match,
},
};
module_platform_driver(jh7110_timer_driver);
MODULE_AUTHOR("Xingyu Wu <xingyu.wu@starfivetech.com>");
MODULE_DESCRIPTION("StarFive JH7110 timer driver");
MODULE_LICENSE("GPL");