[mirror_ubuntu-artful-kernel.git] / arch / arm / mach-u300 / timer.c

/*
 *
 * arch/arm/mach-u300/timer.c
 *
 *
 * Copyright (C) 2007-2009 ST-Ericsson AB
 * License terms: GNU General Public License (GPL) version 2
 * Timer COH 901 328, runs the OS timer interrupt.
 * Author: Linus Walleij <linus.walleij@stericsson.com>
 */
#include <linux/interrupt.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/types.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/err.h>

#include <mach/hardware.h>

/* Generic stuff */
#include <asm/sched_clock.h>
#include <asm/mach/map.h>
#include <asm/mach/time.h>
#include <asm/mach/irq.h>

#include "timer.h"

/*
 * APP side special timer registers
 * This timer contains four timers which can fire an interrupt each.
 * OS (operating system) timer @ 32768 Hz
 * DD (device driver) timer @ 1 kHz
 * GP1 (general purpose 1) timer @ 1MHz
 * GP2 (general purpose 2) timer @ 1MHz
 */

/* Reset OS Timer 32bit (-/W) */
#define U300_TIMER_APP_ROST					(0x0000)
#define U300_TIMER_APP_ROST_TIMER_RESET				(0x00000000)
/* Enable OS Timer 32bit (-/W) */
#define U300_TIMER_APP_EOST					(0x0004)
#define U300_TIMER_APP_EOST_TIMER_ENABLE			(0x00000000)
/* Disable OS Timer 32bit (-/W) */
#define U300_TIMER_APP_DOST					(0x0008)
#define U300_TIMER_APP_DOST_TIMER_DISABLE			(0x00000000)
/* OS Timer Mode Register 32bit (-/W) */
#define U300_TIMER_APP_SOSTM					(0x000c)
#define U300_TIMER_APP_SOSTM_MODE_CONTINUOUS			(0x00000000)
#define U300_TIMER_APP_SOSTM_MODE_ONE_SHOT			(0x00000001)
/* OS Timer Status Register 32bit (R/-) */
#define U300_TIMER_APP_OSTS					(0x0010)
#define U300_TIMER_APP_OSTS_TIMER_STATE_MASK			(0x0000000F)
#define U300_TIMER_APP_OSTS_TIMER_STATE_IDLE			(0x00000001)
#define U300_TIMER_APP_OSTS_TIMER_STATE_ACTIVE			(0x00000002)
#define U300_TIMER_APP_OSTS_ENABLE_IND				(0x00000010)
#define U300_TIMER_APP_OSTS_MODE_MASK				(0x00000020)
#define U300_TIMER_APP_OSTS_MODE_CONTINUOUS			(0x00000000)
#define U300_TIMER_APP_OSTS_MODE_ONE_SHOT			(0x00000020)
#define U300_TIMER_APP_OSTS_IRQ_ENABLED_IND			(0x00000040)
#define U300_TIMER_APP_OSTS_IRQ_PENDING_IND			(0x00000080)
/* OS Timer Current Count Register 32bit (R/-) */
#define U300_TIMER_APP_OSTCC					(0x0014)
/* OS Timer Terminal Count Register 32bit (R/W) */
#define U300_TIMER_APP_OSTTC					(0x0018)
/* OS Timer Interrupt Enable Register 32bit (-/W) */
#define U300_TIMER_APP_OSTIE					(0x001c)
#define U300_TIMER_APP_OSTIE_IRQ_DISABLE			(0x00000000)
#define U300_TIMER_APP_OSTIE_IRQ_ENABLE				(0x00000001)
/* OS Timer Interrupt Acknowledge Register 32bit (-/W) */
#define U300_TIMER_APP_OSTIA					(0x0020)
#define U300_TIMER_APP_OSTIA_IRQ_ACK				(0x00000080)

/* Reset DD Timer 32bit (-/W) */
#define U300_TIMER_APP_RDDT					(0x0040)
#define U300_TIMER_APP_RDDT_TIMER_RESET				(0x00000000)
/* Enable DD Timer 32bit (-/W) */
#define U300_TIMER_APP_EDDT					(0x0044)
#define U300_TIMER_APP_EDDT_TIMER_ENABLE			(0x00000000)
/* Disable DD Timer 32bit (-/W) */
#define U300_TIMER_APP_DDDT					(0x0048)
#define U300_TIMER_APP_DDDT_TIMER_DISABLE			(0x00000000)
/* DD Timer Mode Register 32bit (-/W) */
#define U300_TIMER_APP_SDDTM					(0x004c)
#define U300_TIMER_APP_SDDTM_MODE_CONTINUOUS			(0x00000000)
#define U300_TIMER_APP_SDDTM_MODE_ONE_SHOT			(0x00000001)
/* DD Timer Status Register 32bit (R/-) */
#define U300_TIMER_APP_DDTS					(0x0050)
#define U300_TIMER_APP_DDTS_TIMER_STATE_MASK			(0x0000000F)
#define U300_TIMER_APP_DDTS_TIMER_STATE_IDLE			(0x00000001)
#define U300_TIMER_APP_DDTS_TIMER_STATE_ACTIVE			(0x00000002)
#define U300_TIMER_APP_DDTS_ENABLE_IND				(0x00000010)
#define U300_TIMER_APP_DDTS_MODE_MASK				(0x00000020)
#define U300_TIMER_APP_DDTS_MODE_CONTINUOUS			(0x00000000)
#define U300_TIMER_APP_DDTS_MODE_ONE_SHOT			(0x00000020)
#define U300_TIMER_APP_DDTS_IRQ_ENABLED_IND			(0x00000040)
#define U300_TIMER_APP_DDTS_IRQ_PENDING_IND			(0x00000080)
/* DD Timer Current Count Register 32bit (R/-) */
#define U300_TIMER_APP_DDTCC					(0x0054)
/* DD Timer Terminal Count Register 32bit (R/W) */
#define U300_TIMER_APP_DDTTC					(0x0058)
/* DD Timer Interrupt Enable Register 32bit (-/W) */
#define U300_TIMER_APP_DDTIE					(0x005c)
#define U300_TIMER_APP_DDTIE_IRQ_DISABLE			(0x00000000)
#define U300_TIMER_APP_DDTIE_IRQ_ENABLE				(0x00000001)
/* DD Timer Interrupt Acknowledge Register 32bit (-/W) */
#define U300_TIMER_APP_DDTIA					(0x0060)
#define U300_TIMER_APP_DDTIA_IRQ_ACK				(0x00000080)

/* Reset GP1 Timer 32bit (-/W) */
#define U300_TIMER_APP_RGPT1					(0x0080)
#define U300_TIMER_APP_RGPT1_TIMER_RESET			(0x00000000)
/* Enable GP1 Timer 32bit (-/W) */
#define U300_TIMER_APP_EGPT1					(0x0084)
#define U300_TIMER_APP_EGPT1_TIMER_ENABLE			(0x00000000)
/* Disable GP1 Timer 32bit (-/W) */
#define U300_TIMER_APP_DGPT1					(0x0088)
#define U300_TIMER_APP_DGPT1_TIMER_DISABLE			(0x00000000)
/* GP1 Timer Mode Register 32bit (-/W) */
#define U300_TIMER_APP_SGPT1M					(0x008c)
#define U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS			(0x00000000)
#define U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT			(0x00000001)
/* GP1 Timer Status Register 32bit (R/-) */
#define U300_TIMER_APP_GPT1S					(0x0090)
#define U300_TIMER_APP_GPT1S_TIMER_STATE_MASK			(0x0000000F)
#define U300_TIMER_APP_GPT1S_TIMER_STATE_IDLE			(0x00000001)
#define U300_TIMER_APP_GPT1S_TIMER_STATE_ACTIVE			(0x00000002)
#define U300_TIMER_APP_GPT1S_ENABLE_IND				(0x00000010)
#define U300_TIMER_APP_GPT1S_MODE_MASK				(0x00000020)
#define U300_TIMER_APP_GPT1S_MODE_CONTINUOUS			(0x00000000)
#define U300_TIMER_APP_GPT1S_MODE_ONE_SHOT			(0x00000020)
#define U300_TIMER_APP_GPT1S_IRQ_ENABLED_IND			(0x00000040)
#define U300_TIMER_APP_GPT1S_IRQ_PENDING_IND			(0x00000080)
/* GP1 Timer Current Count Register 32bit (R/-) */
#define U300_TIMER_APP_GPT1CC					(0x0094)
/* GP1 Timer Terminal Count Register 32bit (R/W) */
#define U300_TIMER_APP_GPT1TC					(0x0098)
/* GP1 Timer Interrupt Enable Register 32bit (-/W) */
#define U300_TIMER_APP_GPT1IE					(0x009c)
#define U300_TIMER_APP_GPT1IE_IRQ_DISABLE			(0x00000000)
#define U300_TIMER_APP_GPT1IE_IRQ_ENABLE			(0x00000001)
/* GP1 Timer Interrupt Acknowledge Register 32bit (-/W) */
#define U300_TIMER_APP_GPT1IA					(0x00a0)
#define U300_TIMER_APP_GPT1IA_IRQ_ACK				(0x00000080)

/* Reset GP2 Timer 32bit (-/W) */
#define U300_TIMER_APP_RGPT2					(0x00c0)
#define U300_TIMER_APP_RGPT2_TIMER_RESET			(0x00000000)
/* Enable GP2 Timer 32bit (-/W) */
#define U300_TIMER_APP_EGPT2					(0x00c4)
#define U300_TIMER_APP_EGPT2_TIMER_ENABLE			(0x00000000)
/* Disable GP2 Timer 32bit (-/W) */
#define U300_TIMER_APP_DGPT2					(0x00c8)
#define U300_TIMER_APP_DGPT2_TIMER_DISABLE			(0x00000000)
/* GP2 Timer Mode Register 32bit (-/W) */
#define U300_TIMER_APP_SGPT2M					(0x00cc)
#define U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS			(0x00000000)
#define U300_TIMER_APP_SGPT2M_MODE_ONE_SHOT			(0x00000001)
/* GP2 Timer Status Register 32bit (R/-) */
#define U300_TIMER_APP_GPT2S					(0x00d0)
#define U300_TIMER_APP_GPT2S_TIMER_STATE_MASK			(0x0000000F)
#define U300_TIMER_APP_GPT2S_TIMER_STATE_IDLE			(0x00000001)
#define U300_TIMER_APP_GPT2S_TIMER_STATE_ACTIVE			(0x00000002)
#define U300_TIMER_APP_GPT2S_ENABLE_IND				(0x00000010)
#define U300_TIMER_APP_GPT2S_MODE_MASK				(0x00000020)
#define U300_TIMER_APP_GPT2S_MODE_CONTINUOUS			(0x00000000)
#define U300_TIMER_APP_GPT2S_MODE_ONE_SHOT			(0x00000020)
#define U300_TIMER_APP_GPT2S_IRQ_ENABLED_IND			(0x00000040)
#define U300_TIMER_APP_GPT2S_IRQ_PENDING_IND			(0x00000080)
/* GP2 Timer Current Count Register 32bit (R/-) */
#define U300_TIMER_APP_GPT2CC					(0x00d4)
/* GP2 Timer Terminal Count Register 32bit (R/W) */
#define U300_TIMER_APP_GPT2TC					(0x00d8)
/* GP2 Timer Interrupt Enable Register 32bit (-/W) */
#define U300_TIMER_APP_GPT2IE					(0x00dc)
#define U300_TIMER_APP_GPT2IE_IRQ_DISABLE			(0x00000000)
#define U300_TIMER_APP_GPT2IE_IRQ_ENABLE			(0x00000001)
/* GP2 Timer Interrupt Acknowledge Register 32bit (-/W) */
#define U300_TIMER_APP_GPT2IA					(0x00e0)
#define U300_TIMER_APP_GPT2IA_IRQ_ACK				(0x00000080)

/* Clock request control register - all four timers */
#define U300_TIMER_APP_CRC					(0x100)
#define U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE			(0x00000001)

#define TICKS_PER_JIFFY ((CLOCK_TICK_RATE + (HZ/2)) / HZ)
#define US_PER_TICK ((1000000 + (HZ/2)) / HZ)

/*
 * The u300_set_mode() function is always called first, if we
 * have oneshot timer active, the oneshot scheduling function
 * u300_set_next_event() is called immediately after.
 */
static void u300_set_mode(enum clock_event_mode mode,
			  struct clock_event_device *evt)
{
	switch (mode) {
	case CLOCK_EVT_MODE_PERIODIC:
		/* Disable interrupts on GPT1 */
		writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
		/* Disable GP1 while we're reprogramming it. */
		writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
		/*
		 * Set the periodic mode to a certain number of ticks per
		 * jiffy.
		 */
		writel(TICKS_PER_JIFFY,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1TC);
		/*
		 * Set continuous mode, so the timer keeps triggering
		 * interrupts.
		 */
		writel(U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT1M);
		/* Enable timer interrupts */
		writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
		/* Then enable the OS timer again */
		writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT1);
		break;
	case CLOCK_EVT_MODE_ONESHOT:
		/* Just break; here? */
		/*
		 * The actual event will be programmed by the next event hook,
		 * so we just set a dummy value somewhere at the end of the
		 * universe here.
		 */
		/* Disable interrupts on GPT1 */
		writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
		/* Disable GP1 while we're reprogramming it. */
		writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
		/*
		 * Expire far in the future, u300_set_next_event() will be
		 * called soon...
		 */
		writel(0xFFFFFFFF, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1TC);
		/* We run one shot per tick here! */
		writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT1M);
		/* Enable interrupts for this timer */
		writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
		/* Enable timer */
		writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT1);
		break;
	case CLOCK_EVT_MODE_UNUSED:
	case CLOCK_EVT_MODE_SHUTDOWN:
		/* Disable interrupts on GP1 */
		writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
		/* Disable GP1 */
		writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
		       U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
		break;
	case CLOCK_EVT_MODE_RESUME:
		/* Ignore this call */
		break;
	}
}

/*
 * The app timer in one shot mode obviously has to be reprogrammed
 * in EXACTLY this sequence to work properly. Do NOT try to e.g. replace
 * the interrupt disable + timer disable commands with a reset command,
 * it will fail miserably. Apparently (and I found this the hard way)
 * the timer is very sensitive to the instruction order, though you don't
 * get that impression from the data sheet.
 */
static int u300_set_next_event(unsigned long cycles,
			       struct clock_event_device *evt)

{
	/* Disable interrupts on GPT1 */
	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
	       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
	/* Disable GP1 while we're reprogramming it. */
	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
	       U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
	/* Reset the General Purpose timer 1. */
	writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
	       U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT1);
	/* IRQ in n * cycles */
	writel(cycles, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1TC);
	/*
	 * We run one shot per tick here! (This is necessary to reconfigure,
	 * the timer will tilt if you don't!)
	 */
	writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
	       U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT1M);
	/* Enable timer interrupts */
	writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
	       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
	/* Then enable the OS timer again */
	writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
	       U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT1);
	return 0;
}


/* Use general purpose timer 1 as clock event */
static struct clock_event_device clockevent_u300_1mhz = {
	.name		= "GPT1",
	.rating		= 300, /* Reasonably fast and accurate clock event */
	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
	.set_next_event	= u300_set_next_event,
	.set_mode	= u300_set_mode,
};

/* Clock event timer interrupt handler */
static irqreturn_t u300_timer_interrupt(int irq, void *dev_id)
{
	struct clock_event_device *evt = &clockevent_u300_1mhz;
	/* ACK/Clear timer IRQ for the APP GPT1 Timer */
	writel(U300_TIMER_APP_GPT1IA_IRQ_ACK,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IA);
	evt->event_handler(evt);
	return IRQ_HANDLED;
}

static struct irqaction u300_timer_irq = {
	.name		= "U300 Timer Tick",
	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
	.handler	= u300_timer_interrupt,
};

/*
 * Override the global weak sched_clock symbol with this
 * local implementation which uses the clocksource to get some
 * better resolution when scheduling the kernel. We accept that
 * this wraps around for now, since it is just a relative time
 * stamp. (Inspired by OMAP implementation.)
 */

static u32 notrace u300_read_sched_clock(void)
{
	return readl(U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2CC);
}


/*
 * This sets up the system timers, clock source and clock event.
 */
static void __init u300_timer_init(void)
{
	struct clk *clk;
	unsigned long rate;

	/* Clock the interrupt controller */
	clk = clk_get_sys("apptimer", NULL);
	BUG_ON(IS_ERR(clk));
	clk_prepare_enable(clk);
	rate = clk_get_rate(clk);

	setup_sched_clock(u300_read_sched_clock, 32, rate);

	/*
	 * Disable the "OS" and "DD" timers - these are designed for Symbian!
	 * Example usage in cnh1601578 cpu subsystem pd_timer_app.c
	 */
	writel(U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_CRC);
	writel(U300_TIMER_APP_ROST_TIMER_RESET,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_ROST);
	writel(U300_TIMER_APP_DOST_TIMER_DISABLE,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_DOST);
	writel(U300_TIMER_APP_RDDT_TIMER_RESET,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_RDDT);
	writel(U300_TIMER_APP_DDDT_TIMER_DISABLE,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_DDDT);

	/* Reset the General Purpose timer 1. */
	writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT1);

	/* Set up the IRQ handler */
	setup_irq(IRQ_U300_TIMER_APP_GP1, &u300_timer_irq);

	/* Reset the General Purpose timer 2 */
	writel(U300_TIMER_APP_RGPT2_TIMER_RESET,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT2);
	/* Set this timer to run around forever */
	writel(0xFFFFFFFFU, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2TC);
	/* Set continuous mode so it wraps around */
	writel(U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS,
	       U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT2M);
	/* Disable timer interrupts */
	writel(U300_TIMER_APP_GPT2IE_IRQ_DISABLE,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2IE);
	/* Then enable the GP2 timer to use as a free running us counter */
	writel(U300_TIMER_APP_EGPT2_TIMER_ENABLE,
		U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT2);

	/* Use general purpose timer 2 as clock source */
	if (clocksource_mmio_init(U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2CC,
			"GPT2", rate, 300, 32, clocksource_mmio_readl_up))
		pr_err("timer: failed to initialize U300 clock source\n");

	/* Configure and register the clockevent */
	clockevents_config_and_register(&clockevent_u300_1mhz, rate,
					1, 0xffffffff);

	/*
	 * TODO: init and register the rest of the timers too, they can be
	 * used by hrtimers!
	 */
}

/*
 * Very simple system timer that only register the clock event and
 * clock source.
 */
struct sys_timer u300_timer = {
	.init		= u300_timer_init,
};
Commit	Line	Data
bb3cee2b LW	1	/*
	2	*
	3	* arch/arm/mach-u300/timer.c
	4	*
	5	*
	6	* Copyright (C) 2007-2009 ST-Ericsson AB
	7	* License terms: GNU General Public License (GPL) version 2
	8	* Timer COH 901 328, runs the OS timer interrupt.
	9	* Author: Linus Walleij <linus.walleij@stericsson.com>
	10	*/
	11	#include <linux/interrupt.h>
	12	#include <linux/time.h>
	13	#include <linux/timex.h>
	14	#include <linux/clockchips.h>
	15	#include <linux/clocksource.h>
	16	#include <linux/types.h>
	17	#include <linux/io.h>
b7276b23 LW	18	#include <linux/clk.h>
b7276b23 LW	19	#include <linux/err.h>
bb3cee2b LW	20
	21	#include <mach/hardware.h>
	22
	23	/* Generic stuff */
5c21b7ca	24	#include <asm/sched_clock.h>
bb3cee2b LW	25	#include <asm/mach/map.h>
	26	#include <asm/mach/time.h>
	27	#include <asm/mach/irq.h>
	28
234323ba LW	29	#include "timer.h"
234323ba LW	30
bb3cee2b LW	31	/*
	32	* APP side special timer registers
	33	* This timer contains four timers which can fire an interrupt each.
	34	* OS (operating system) timer @ 32768 Hz
	35	* DD (device driver) timer @ 1 kHz
	36	* GP1 (general purpose 1) timer @ 1MHz
	37	* GP2 (general purpose 2) timer @ 1MHz
	38	*/
	39
	40	/* Reset OS Timer 32bit (-/W) */
	41	#define U300_TIMER_APP_ROST (0x0000)
	42	#define U300_TIMER_APP_ROST_TIMER_RESET (0x00000000)
	43	/* Enable OS Timer 32bit (-/W) */
	44	#define U300_TIMER_APP_EOST (0x0004)
	45	#define U300_TIMER_APP_EOST_TIMER_ENABLE (0x00000000)
	46	/* Disable OS Timer 32bit (-/W) */
	47	#define U300_TIMER_APP_DOST (0x0008)
	48	#define U300_TIMER_APP_DOST_TIMER_DISABLE (0x00000000)
	49	/* OS Timer Mode Register 32bit (-/W) */
	50	#define U300_TIMER_APP_SOSTM (0x000c)
	51	#define U300_TIMER_APP_SOSTM_MODE_CONTINUOUS (0x00000000)
	52	#define U300_TIMER_APP_SOSTM_MODE_ONE_SHOT (0x00000001)
	53	/* OS Timer Status Register 32bit (R/-) */
	54	#define U300_TIMER_APP_OSTS (0x0010)
	55	#define U300_TIMER_APP_OSTS_TIMER_STATE_MASK (0x0000000F)
	56	#define U300_TIMER_APP_OSTS_TIMER_STATE_IDLE (0x00000001)
	57	#define U300_TIMER_APP_OSTS_TIMER_STATE_ACTIVE (0x00000002)
	58	#define U300_TIMER_APP_OSTS_ENABLE_IND (0x00000010)
	59	#define U300_TIMER_APP_OSTS_MODE_MASK (0x00000020)
	60	#define U300_TIMER_APP_OSTS_MODE_CONTINUOUS (0x00000000)
	61	#define U300_TIMER_APP_OSTS_MODE_ONE_SHOT (0x00000020)
	62	#define U300_TIMER_APP_OSTS_IRQ_ENABLED_IND (0x00000040)
	63	#define U300_TIMER_APP_OSTS_IRQ_PENDING_IND (0x00000080)
	64	/* OS Timer Current Count Register 32bit (R/-) */
	65	#define U300_TIMER_APP_OSTCC (0x0014)
	66	/* OS Timer Terminal Count Register 32bit (R/W) */
	67	#define U300_TIMER_APP_OSTTC (0x0018)
	68	/* OS Timer Interrupt Enable Register 32bit (-/W) */
	69	#define U300_TIMER_APP_OSTIE (0x001c)
	70	#define U300_TIMER_APP_OSTIE_IRQ_DISABLE (0x00000000)
	71	#define U300_TIMER_APP_OSTIE_IRQ_ENABLE (0x00000001)
	72	/* OS Timer Interrupt Acknowledge Register 32bit (-/W) */
	73	#define U300_TIMER_APP_OSTIA (0x0020)
	74	#define U300_TIMER_APP_OSTIA_IRQ_ACK (0x00000080)
	75
	76	/* Reset DD Timer 32bit (-/W) */
	77	#define U300_TIMER_APP_RDDT (0x0040)
	78	#define U300_TIMER_APP_RDDT_TIMER_RESET (0x00000000)
	79	/* Enable DD Timer 32bit (-/W) */
	80	#define U300_TIMER_APP_EDDT (0x0044)
	81	#define U300_TIMER_APP_EDDT_TIMER_ENABLE (0x00000000)
	82	/* Disable DD Timer 32bit (-/W) */
	83	#define U300_TIMER_APP_DDDT (0x0048)
	84	#define U300_TIMER_APP_DDDT_TIMER_DISABLE (0x00000000)
	85	/* DD Timer Mode Register 32bit (-/W) */
	86	#define U300_TIMER_APP_SDDTM (0x004c)
	87	#define U300_TIMER_APP_SDDTM_MODE_CONTINUOUS (0x00000000)
	88	#define U300_TIMER_APP_SDDTM_MODE_ONE_SHOT (0x00000001)
	89	/* DD Timer Status Register 32bit (R/-) */
	90	#define U300_TIMER_APP_DDTS (0x0050)
	91	#define U300_TIMER_APP_DDTS_TIMER_STATE_MASK (0x0000000F)
	92	#define U300_TIMER_APP_DDTS_TIMER_STATE_IDLE (0x00000001)
	93	#define U300_TIMER_APP_DDTS_TIMER_STATE_ACTIVE (0x00000002)
	94	#define U300_TIMER_APP_DDTS_ENABLE_IND (0x00000010)
95	#define U300_TIMER_APP_DDTS_MODE_MASK (0x00000020)
96	#define U300_TIMER_APP_DDTS_MODE_CONTINUOUS (0x00000000)
97	#define U300_TIMER_APP_DDTS_MODE_ONE_SHOT (0x00000020)
98	#define U300_TIMER_APP_DDTS_IRQ_ENABLED_IND (0x00000040)
99	#define U300_TIMER_APP_DDTS_IRQ_PENDING_IND (0x00000080)
100	/* DD Timer Current Count Register 32bit (R/-) */
101	#define U300_TIMER_APP_DDTCC (0x0054)
102	/* DD Timer Terminal Count Register 32bit (R/W) */
103	#define U300_TIMER_APP_DDTTC (0x0058)
104	/* DD Timer Interrupt Enable Register 32bit (-/W) */
105	#define U300_TIMER_APP_DDTIE (0x005c)
106	#define U300_TIMER_APP_DDTIE_IRQ_DISABLE (0x00000000)
107	#define U300_TIMER_APP_DDTIE_IRQ_ENABLE (0x00000001)
108	/* DD Timer Interrupt Acknowledge Register 32bit (-/W) */
109	#define U300_TIMER_APP_DDTIA (0x0060)
110	#define U300_TIMER_APP_DDTIA_IRQ_ACK (0x00000080)
111
112	/* Reset GP1 Timer 32bit (-/W) */
113	#define U300_TIMER_APP_RGPT1 (0x0080)
114	#define U300_TIMER_APP_RGPT1_TIMER_RESET (0x00000000)
115	/* Enable GP1 Timer 32bit (-/W) */
116	#define U300_TIMER_APP_EGPT1 (0x0084)
117	#define U300_TIMER_APP_EGPT1_TIMER_ENABLE (0x00000000)
118	/* Disable GP1 Timer 32bit (-/W) */
119	#define U300_TIMER_APP_DGPT1 (0x0088)
120	#define U300_TIMER_APP_DGPT1_TIMER_DISABLE (0x00000000)
121	/* GP1 Timer Mode Register 32bit (-/W) */
122	#define U300_TIMER_APP_SGPT1M (0x008c)
123	#define U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS (0x00000000)
124	#define U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT (0x00000001)
125	/* GP1 Timer Status Register 32bit (R/-) */
126	#define U300_TIMER_APP_GPT1S (0x0090)
127	#define U300_TIMER_APP_GPT1S_TIMER_STATE_MASK (0x0000000F)
128	#define U300_TIMER_APP_GPT1S_TIMER_STATE_IDLE (0x00000001)
129	#define U300_TIMER_APP_GPT1S_TIMER_STATE_ACTIVE (0x00000002)
130	#define U300_TIMER_APP_GPT1S_ENABLE_IND (0x00000010)
131	#define U300_TIMER_APP_GPT1S_MODE_MASK (0x00000020)
132	#define U300_TIMER_APP_GPT1S_MODE_CONTINUOUS (0x00000000)
133	#define U300_TIMER_APP_GPT1S_MODE_ONE_SHOT (0x00000020)
134	#define U300_TIMER_APP_GPT1S_IRQ_ENABLED_IND (0x00000040)
135	#define U300_TIMER_APP_GPT1S_IRQ_PENDING_IND (0x00000080)
136	/* GP1 Timer Current Count Register 32bit (R/-) */
137	#define U300_TIMER_APP_GPT1CC (0x0094)
138	/* GP1 Timer Terminal Count Register 32bit (R/W) */
139	#define U300_TIMER_APP_GPT1TC (0x0098)
140	/* GP1 Timer Interrupt Enable Register 32bit (-/W) */
141	#define U300_TIMER_APP_GPT1IE (0x009c)
142	#define U300_TIMER_APP_GPT1IE_IRQ_DISABLE (0x00000000)
143	#define U300_TIMER_APP_GPT1IE_IRQ_ENABLE (0x00000001)
144	/* GP1 Timer Interrupt Acknowledge Register 32bit (-/W) */
145	#define U300_TIMER_APP_GPT1IA (0x00a0)
146	#define U300_TIMER_APP_GPT1IA_IRQ_ACK (0x00000080)
147
148	/* Reset GP2 Timer 32bit (-/W) */
149	#define U300_TIMER_APP_RGPT2 (0x00c0)
150	#define U300_TIMER_APP_RGPT2_TIMER_RESET (0x00000000)
151	/* Enable GP2 Timer 32bit (-/W) */
152	#define U300_TIMER_APP_EGPT2 (0x00c4)
153	#define U300_TIMER_APP_EGPT2_TIMER_ENABLE (0x00000000)
154	/* Disable GP2 Timer 32bit (-/W) */
155	#define U300_TIMER_APP_DGPT2 (0x00c8)
156	#define U300_TIMER_APP_DGPT2_TIMER_DISABLE (0x00000000)
157	/* GP2 Timer Mode Register 32bit (-/W) */
158	#define U300_TIMER_APP_SGPT2M (0x00cc)
159	#define U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS (0x00000000)
160	#define U300_TIMER_APP_SGPT2M_MODE_ONE_SHOT (0x00000001)
161	/* GP2 Timer Status Register 32bit (R/-) */
162	#define U300_TIMER_APP_GPT2S (0x00d0)
163	#define U300_TIMER_APP_GPT2S_TIMER_STATE_MASK (0x0000000F)
164	#define U300_TIMER_APP_GPT2S_TIMER_STATE_IDLE (0x00000001)
165	#define U300_TIMER_APP_GPT2S_TIMER_STATE_ACTIVE (0x00000002)
166	#define U300_TIMER_APP_GPT2S_ENABLE_IND (0x00000010)
167	#define U300_TIMER_APP_GPT2S_MODE_MASK (0x00000020)
168	#define U300_TIMER_APP_GPT2S_MODE_CONTINUOUS (0x00000000)
169	#define U300_TIMER_APP_GPT2S_MODE_ONE_SHOT (0x00000020)
170	#define U300_TIMER_APP_GPT2S_IRQ_ENABLED_IND (0x00000040)
171	#define U300_TIMER_APP_GPT2S_IRQ_PENDING_IND (0x00000080)
172	/* GP2 Timer Current Count Register 32bit (R/-) */
173	#define U300_TIMER_APP_GPT2CC (0x00d4)
174	/* GP2 Timer Terminal Count Register 32bit (R/W) */
175	#define U300_TIMER_APP_GPT2TC (0x00d8)
176	/* GP2 Timer Interrupt Enable Register 32bit (-/W) */
177	#define U300_TIMER_APP_GPT2IE (0x00dc)
178	#define U300_TIMER_APP_GPT2IE_IRQ_DISABLE (0x00000000)
179	#define U300_TIMER_APP_GPT2IE_IRQ_ENABLE (0x00000001)
180	/* GP2 Timer Interrupt Acknowledge Register 32bit (-/W) */
181	#define U300_TIMER_APP_GPT2IA (0x00e0)
182	#define U300_TIMER_APP_GPT2IA_IRQ_ACK (0x00000080)
183
184	/* Clock request control register - all four timers */
185	#define U300_TIMER_APP_CRC (0x100)
186	#define U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE (0x00000001)
187
188	#define TICKS_PER_JIFFY ((CLOCK_TICK_RATE + (HZ/2)) / HZ)
189	#define US_PER_TICK ((1000000 + (HZ/2)) / HZ)
190
191	/*
192	* The u300_set_mode() function is always called first, if we
193	* have oneshot timer active, the oneshot scheduling function
194	* u300_set_next_event() is called immediately after.
195	*/
196	static void u300_set_mode(enum clock_event_mode mode,
197	struct clock_event_device *evt)
198	{
199	switch (mode) {
200	case CLOCK_EVT_MODE_PERIODIC:
201	/* Disable interrupts on GPT1 */
202	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
203	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
204	/* Disable GP1 while we're reprogramming it. */
205	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
206	U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
207	/*
208	* Set the periodic mode to a certain number of ticks per
209	* jiffy.
210	*/
211	writel(TICKS_PER_JIFFY,
212	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1TC);
213	/*
214	* Set continuous mode, so the timer keeps triggering
215	* interrupts.
216	*/
217	writel(U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS,
218	U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT1M);
219	/* Enable timer interrupts */
220	writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
221	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
222	/* Then enable the OS timer again */
223	writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
224	U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT1);
225	break;
226	case CLOCK_EVT_MODE_ONESHOT:
227	/* Just break; here? */
228	/*
229	* The actual event will be programmed by the next event hook,
230	* so we just set a dummy value somewhere at the end of the
231	* universe here.
232	*/
233	/* Disable interrupts on GPT1 */
234	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
235	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
236	/* Disable GP1 while we're reprogramming it. */
237	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
238	U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
239	/*
240	* Expire far in the future, u300_set_next_event() will be
241	* called soon...
242	*/
243	writel(0xFFFFFFFF, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1TC);
244	/* We run one shot per tick here! */
245	writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
246	U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT1M);
247	/* Enable interrupts for this timer */
248	writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
249	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
250	/* Enable timer */
251	writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
252	U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT1);
253	break;
254	case CLOCK_EVT_MODE_UNUSED:
255	case CLOCK_EVT_MODE_SHUTDOWN:
256	/* Disable interrupts on GP1 */
257	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
258	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
259	/* Disable GP1 */
260	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
261	U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
262	break;
263	case CLOCK_EVT_MODE_RESUME:
264	/* Ignore this call */
265	break;
266	}
267	}
268
269	/*
270	* The app timer in one shot mode obviously has to be reprogrammed
271	* in EXACTLY this sequence to work properly. Do NOT try to e.g. replace
272	* the interrupt disable + timer disable commands with a reset command,
273	* it will fail miserably. Apparently (and I found this the hard way)
274	* the timer is very sensitive to the instruction order, though you don't
275	* get that impression from the data sheet.
276	*/
277	static int u300_set_next_event(unsigned long cycles,
278	struct clock_event_device *evt)
279
280	{
281	/* Disable interrupts on GPT1 */
282	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
283	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
284	/* Disable GP1 while we're reprogramming it. */
285	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
286	U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
287	/* Reset the General Purpose timer 1. */
288	writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
289	U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT1);
290	/* IRQ in n * cycles */
291	writel(cycles, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1TC);
292	/*
293	* We run one shot per tick here! (This is necessary to reconfigure,
294	* the timer will tilt if you don't!)
295	*/
296	writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
297	U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT1M);
298	/* Enable timer interrupts */
299	writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
300	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
301	/* Then enable the OS timer again */
302	writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
303	U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT1);
304	return 0;
305	}
306
307
308	/* Use general purpose timer 1 as clock event */
309	static struct clock_event_device clockevent_u300_1mhz = {
cde21de1 LW	310	.name = "GPT1",
	311	.rating = 300, /* Reasonably fast and accurate clock event */
	312	.features = CLOCK_EVT_FEAT_PERIODIC \| CLOCK_EVT_FEAT_ONESHOT,
	313	.set_next_event = u300_set_next_event,
	314	.set_mode = u300_set_mode,
bb3cee2b LW	315	};
	316
	317	/* Clock event timer interrupt handler */
	318	static irqreturn_t u300_timer_interrupt(int irq, void *dev_id)
	319	{
	320	struct clock_event_device *evt = &clockevent_u300_1mhz;
	321	/* ACK/Clear timer IRQ for the APP GPT1 Timer */
	322	writel(U300_TIMER_APP_GPT1IA_IRQ_ACK,
	323	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IA);
	324	evt->event_handler(evt);
	325	return IRQ_HANDLED;
	326	}
	327
	328	static struct irqaction u300_timer_irq = {
cde21de1 LW	329	.name = "U300 Timer Tick",
	330	.flags = IRQF_DISABLED \| IRQF_TIMER \| IRQF_IRQPOLL,
	331	.handler = u300_timer_interrupt,
bb3cee2b LW	332	};
bb3cee2b LW	333
a2ca00ea LW	334	/*
	335	* Override the global weak sched_clock symbol with this
	336	* local implementation which uses the clocksource to get some
	337	* better resolution when scheduling the kernel. We accept that
	338	* this wraps around for now, since it is just a relative time
	339	* stamp. (Inspired by OMAP implementation.)
	340	*/
5c21b7ca	341
2f0778af	342	static u32 notrace u300_read_sched_clock(void)
a2ca00ea	343	{
2f0778af	344	return readl(U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2CC);
a2ca00ea LW	345	}
a2ca00ea LW	346
bb3cee2b LW	347
	348	/*
	349	* This sets up the system timers, clock source and clock event.
	350	*/
	351	static void __init u300_timer_init(void)
	352	{
b7276b23	353	struct clk *clk;
3af8a8da	354	unsigned long rate;
b7276b23 LW	355
	356	/* Clock the interrupt controller */
	357	clk = clk_get_sys("apptimer", NULL);
	358	BUG_ON(IS_ERR(clk));
50667d63	359	clk_prepare_enable(clk);
3af8a8da	360	rate = clk_get_rate(clk);
b7276b23	361
2f0778af	362	setup_sched_clock(u300_read_sched_clock, 32, rate);
5c21b7ca	363
bb3cee2b LW	364	/*
	365	* Disable the "OS" and "DD" timers - these are designed for Symbian!
	366	* Example usage in cnh1601578 cpu subsystem pd_timer_app.c
	367	*/
	368	writel(U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE,
	369	U300_TIMER_APP_VBASE + U300_TIMER_APP_CRC);
	370	writel(U300_TIMER_APP_ROST_TIMER_RESET,
	371	U300_TIMER_APP_VBASE + U300_TIMER_APP_ROST);
	372	writel(U300_TIMER_APP_DOST_TIMER_DISABLE,
	373	U300_TIMER_APP_VBASE + U300_TIMER_APP_DOST);
	374	writel(U300_TIMER_APP_RDDT_TIMER_RESET,
	375	U300_TIMER_APP_VBASE + U300_TIMER_APP_RDDT);
	376	writel(U300_TIMER_APP_DDDT_TIMER_DISABLE,
	377	U300_TIMER_APP_VBASE + U300_TIMER_APP_DDDT);
	378
	379	/* Reset the General Purpose timer 1. */
	380	writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
	381	U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT1);
	382
	383	/* Set up the IRQ handler */
	384	setup_irq(IRQ_U300_TIMER_APP_GP1, &u300_timer_irq);
	385
	386	/* Reset the General Purpose timer 2 */
	387	writel(U300_TIMER_APP_RGPT2_TIMER_RESET,
	388	U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT2);
	389	/* Set this timer to run around forever */
	390	writel(0xFFFFFFFFU, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2TC);
	391	/* Set continuous mode so it wraps around */
	392	writel(U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS,
	393	U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT2M);
	394	/* Disable timer interrupts */
	395	writel(U300_TIMER_APP_GPT2IE_IRQ_DISABLE,
	396	U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2IE);
	397	/* Then enable the GP2 timer to use as a free running us counter */
	398	writel(U300_TIMER_APP_EGPT2_TIMER_ENABLE,
	399	U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT2);
	400
234b6ced RK	401	/* Use general purpose timer 2 as clock source */
	402	if (clocksource_mmio_init(U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2CC,
	403	"GPT2", rate, 300, 32, clocksource_mmio_readl_up))
9425032b	404	pr_err("timer: failed to initialize U300 clock source\n");
bb3cee2b	405
cde21de1 LW	406	/* Configure and register the clockevent */
	407	clockevents_config_and_register(&clockevent_u300_1mhz, rate,
	408	1, 0xffffffff);
	409
bb3cee2b LW	410	/*
	411	* TODO: init and register the rest of the timers too, they can be
	412	* used by hrtimers!
	413	*/
	414	}
	415
	416	/*
	417	* Very simple system timer that only register the clock event and
	418	* clock source.
	419	*/
	420	struct sys_timer u300_timer = {
	421	.init = u300_timer_init,
	422	};