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Commit f0b7fabe authored by Alexander Shiyan's avatar Alexander Shiyan Committed by Daniel Lezcano
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clocksource: clps711x: Add CLPS711X clocksource driver 



This adds the clocksource driver for Cirrus Logic CLPS711X series SoCs.
Designed primarily for migration CLPS711X subarch for multiplatform & DT,
for this as the "OF" and "non-OF" calls implemented.

Signed-off-by: default avatarAlexander Shiyan <shc_work@mail.ru>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
parent 38941522

drivers/clocksource/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ obj-$(CONFIG_CLKSRC_DBX500_PRCMU) += clksrc-dbx500-prcmu.o 
obj-$(CONFIG_ARMADA_370_XP_TIMER)	+= time-armada-370-xp.o

obj-$(CONFIG_ORION_TIMER)	+= time-orion.o

obj-$(CONFIG_ARCH_BCM2835)	+= bcm2835_timer.o

obj-$(CONFIG_ARCH_CLPS711X)	+= clps711x-timer.o

obj-$(CONFIG_ARCH_MARCO)	+= timer-marco.o

obj-$(CONFIG_ARCH_MOXART)	+= moxart_timer.o

obj-$(CONFIG_ARCH_MXS)		+= mxs_timer.o

drivers/clocksource/clps711x-timer.c

0 → 100644
+131 −0
Original line number Diff line number Diff line 
/*

 *  Cirrus Logic CLPS711X clocksource driver

 *

 *  Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 */



#include <linux/clk.h>

#include <linux/clockchips.h>

#include <linux/clocksource.h>

#include <linux/interrupt.h>

#include <linux/io.h>

#include <linux/of_address.h>

#include <linux/of_irq.h>

#include <linux/sched_clock.h>

#include <linux/slab.h>



enum {

	CLPS711X_CLKSRC_CLOCKSOURCE,

	CLPS711X_CLKSRC_CLOCKEVENT,

};



static void __iomem *tcd;



static u64 notrace clps711x_sched_clock_read(void)

{

	return ~readw(tcd);

}



static int __init _clps711x_clksrc_init(struct clk *clock, void __iomem *base)

{

	unsigned long rate;



	if (!base)

		return -ENOMEM;

	if (IS_ERR(clock))

		return PTR_ERR(clock);



	rate = clk_get_rate(clock);



	tcd = base;



	clocksource_mmio_init(tcd, "clps711x-clocksource", rate, 300, 16,

			      clocksource_mmio_readw_down);



	sched_clock_register(clps711x_sched_clock_read, 16, rate);



	return 0;

}



static irqreturn_t clps711x_timer_interrupt(int irq, void *dev_id)

{

	struct clock_event_device *evt = dev_id;



	evt->event_handler(evt);



	return IRQ_HANDLED;

}



static void clps711x_clockevent_set_mode(enum clock_event_mode mode,

					 struct clock_event_device *evt)

{

}



static int __init _clps711x_clkevt_init(struct clk *clock, void __iomem *base,

					unsigned int irq)

{

	struct clock_event_device *clkevt;

	unsigned long rate;



	if (!irq)

		return -EINVAL;

	if (!base)

		return -ENOMEM;

	if (IS_ERR(clock))

		return PTR_ERR(clock);



	clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL);

	if (!clkevt)

		return -ENOMEM;



	rate = clk_get_rate(clock);



	/* Set Timer prescaler */

	writew(DIV_ROUND_CLOSEST(rate, HZ), base);



	clkevt->name = "clps711x-clockevent";

	clkevt->rating = 300;

	clkevt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_C3STOP;

	clkevt->set_mode = clps711x_clockevent_set_mode;

	clkevt->cpumask = cpumask_of(0);

	clockevents_config_and_register(clkevt, HZ, 0, 0);



	return request_irq(irq, clps711x_timer_interrupt, IRQF_TIMER,

			   "clps711x-timer", clkevt);

}



void __init clps711x_clksrc_init(void __iomem *tc1_base, void __iomem *tc2_base,

				 unsigned int irq)

{

	struct clk *tc1 = clk_get_sys("clps711x-timer.0", NULL);

	struct clk *tc2 = clk_get_sys("clps711x-timer.1", NULL);



	BUG_ON(_clps711x_clksrc_init(tc1, tc1_base));

	BUG_ON(_clps711x_clkevt_init(tc2, tc2_base, irq));

}



#ifdef CONFIG_CLKSRC_OF

static void __init clps711x_timer_init(struct device_node *np)

{

	unsigned int irq = irq_of_parse_and_map(np, 0);

	struct clk *clock = of_clk_get(np, 0);

	void __iomem *base = of_iomap(np, 0);



	switch (of_alias_get_id(np, "timer")) {

	case CLPS711X_CLKSRC_CLOCKSOURCE:

		BUG_ON(_clps711x_clksrc_init(clock, base));

		break;

	case CLPS711X_CLKSRC_CLOCKEVENT:

		BUG_ON(_clps711x_clkevt_init(clock, base, irq));

		break;

	default:

		break;

	}

}

CLOCKSOURCE_OF_DECLARE(clps711x, "cirrus,clps711x-timer", clps711x_timer_init);

#endif