Commit 418062b5 authored by Peng Fan's avatar Peng Fan Committed by Daniel Lezcano
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clocksource/drivers/imx-sysctr: Drop use global variables 



Clean up code to not use global variables and introduce sysctr_private
structure to prepare the support for i.MX95.

Signed-off-by: default avatarPeng Fan <peng.fan@nxp.com>
Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20240205-imx-sysctr-v4-2-ca5a6e1552e7@nxp.com
parent 8ec11bd8

drivers/clocksource/timer-imx-sysctr.c

+44 −32
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 


#include <linux/interrupt.h>

#include <linux/clockchips.h>

#include <linux/slab.h>



#include "timer-of.h"
@@ -20,32 +21,39 @@ 


#define SYS_CTR_CLK_DIV		0x3



static void __iomem *sys_ctr_base __ro_after_init;

static u32 cmpcr __ro_after_init;

struct sysctr_private {

	u32 cmpcr;

};



static void sysctr_timer_enable(bool enable)

static void sysctr_timer_enable(struct clock_event_device *evt, bool enable)

{

	writel(enable ? cmpcr | SYS_CTR_EN : cmpcr, sys_ctr_base + CMPCR);

	struct timer_of *to = to_timer_of(evt);

	struct sysctr_private *priv = to->private_data;

	void __iomem *base = timer_of_base(to);



	writel(enable ? priv->cmpcr | SYS_CTR_EN : priv->cmpcr, base + CMPCR);

}



static void sysctr_irq_acknowledge(void)

static void sysctr_irq_acknowledge(struct clock_event_device *evt)

{

	/*

	 * clear the enable bit(EN =0) will clear

	 * the status bit(ISTAT = 0), then the interrupt

	 * signal will be negated(acknowledged).

	 */

	sysctr_timer_enable(false);

	sysctr_timer_enable(evt, false);

}



static inline u64 sysctr_read_counter(void)

static inline u64 sysctr_read_counter(struct clock_event_device *evt)

{

	struct timer_of *to = to_timer_of(evt);

	void __iomem *base = timer_of_base(to);

	u32 cnt_hi, tmp_hi, cnt_lo;



	do {

		cnt_hi = readl_relaxed(sys_ctr_base + CNTCV_HI);

		cnt_lo = readl_relaxed(sys_ctr_base + CNTCV_LO);

		tmp_hi = readl_relaxed(sys_ctr_base + CNTCV_HI);

		cnt_hi = readl_relaxed(base + CNTCV_HI);

		cnt_lo = readl_relaxed(base + CNTCV_LO);

		tmp_hi = readl_relaxed(base + CNTCV_HI);

	} while (tmp_hi != cnt_hi);



	return  ((u64) cnt_hi << 32) | cnt_lo;
@@ -54,22 +62,24 @@ static inline u64 sysctr_read_counter(void) 
static int sysctr_set_next_event(unsigned long delta,

				 struct clock_event_device *evt)

{

	struct timer_of *to = to_timer_of(evt);

	void __iomem *base = timer_of_base(to);

	u32 cmp_hi, cmp_lo;

	u64 next;



	sysctr_timer_enable(false);

	sysctr_timer_enable(evt, false);



	next = sysctr_read_counter();

	next = sysctr_read_counter(evt);



	next += delta;



	cmp_hi = (next >> 32) & 0x00fffff;

	cmp_lo = next & 0xffffffff;



	writel_relaxed(cmp_hi, sys_ctr_base + CMPCV_HI);

	writel_relaxed(cmp_lo, sys_ctr_base + CMPCV_LO);

	writel_relaxed(cmp_hi, base + CMPCV_HI);

	writel_relaxed(cmp_lo, base + CMPCV_LO);



	sysctr_timer_enable(true);

	sysctr_timer_enable(evt, true);



	return 0;

}
@@ -81,7 +91,7 @@ static int sysctr_set_state_oneshot(struct clock_event_device *evt) 


static int sysctr_set_state_shutdown(struct clock_event_device *evt)

{

	sysctr_timer_enable(false);

	sysctr_timer_enable(evt, false);



	return 0;

}
@@ -90,7 +100,7 @@ static irqreturn_t sysctr_timer_interrupt(int irq, void *dev_id) 
{

	struct clock_event_device *evt = dev_id;



	sysctr_irq_acknowledge();

	sysctr_irq_acknowledge(evt);



	evt->event_handler(evt);
@@ -117,34 +127,36 @@ static struct timer_of to_sysctr = { 
	},

};



static void __init sysctr_clockevent_init(void)

{

	to_sysctr.clkevt.cpumask = cpu_possible_mask;



	clockevents_config_and_register(&to_sysctr.clkevt,

					timer_of_rate(&to_sysctr),

					0xff, 0x7fffffff);

}



static int __init sysctr_timer_init(struct device_node *np)

{

	int ret = 0;

	struct sysctr_private *priv;

	void __iomem *base;

	int ret;



	priv = kzalloc(sizeof(struct sysctr_private), GFP_KERNEL);

	if (!priv)

		return -ENOMEM;



	ret = timer_of_init(np, &to_sysctr);

	if (ret)

	if (ret) {

		kfree(priv);

		return ret;

	}



	if (!of_property_read_bool(np, "nxp,no-divider")) {

		/* system counter clock is divided by 3 internally */

		to_sysctr.of_clk.rate /= SYS_CTR_CLK_DIV;

	}



	sys_ctr_base = timer_of_base(&to_sysctr);

	cmpcr = readl(sys_ctr_base + CMPCR);

	cmpcr &= ~SYS_CTR_EN;

	to_sysctr.clkevt.cpumask = cpu_possible_mask;

	to_sysctr.private_data = priv;



	sysctr_clockevent_init();

	base = timer_of_base(&to_sysctr);

	priv->cmpcr = readl(base + CMPCR) & ~SYS_CTR_EN;



	clockevents_config_and_register(&to_sysctr.clkevt,

					timer_of_rate(&to_sysctr),

					0xff, 0x7fffffff);

	return 0;

}

TIMER_OF_DECLARE(sysctr_timer, "nxp,sysctr-timer", sysctr_timer_init);