Merge branch 'u300' into devel

Conflicts:
	arch/arm/Makefile
Updates:
	arch/arm/mach-u300/core.c
	arch/arm/mach-u300/timer.c

1 files changed, 422 insertions, 0 deletions

diff --git a/arch/arm/mach-u300/timer.c b/arch/arm/mach-u300/timer.c
new file mode 100644
index 000000000000..cce53204880e
--- /dev/null
+++ b/arch/arm/mach-u300/timer.c
@@ -0,0 +1,422 @@
+/*
+ *
+ * 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 <mach/hardware.h>
+
+/* Generic stuff */
+#include <asm/mach/map.h>
+#include <asm/mach/time.h>
+#include <asm/mach/irq.h>
+
+#include "clock.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,
+        /* 22 calculated using the algorithm in arch/mips/kernel/time.c */
+        .shift          = 22,
+        .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,
+};
+
+/* Use general purpose timer 2 as clock source */
+static cycle_t u300_get_cycles(struct clocksource *cs)
+{
+        return (cycles_t) readl(U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2CC);
+}
+
+static struct clocksource clocksource_u300_1mhz = {
+        .name           = "GPT2",
+        .rating         = 300, /* Reasonably fast and accurate clock source */
+        .read           = u300_get_cycles,
+        .mask           = CLOCKSOURCE_MASK(32), /* 32 bits */
+        /* 22 calculated using the algorithm in arch/mips/kernel/time.c */
+        .shift          = 22,
+        .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+
+/*
+ * This sets up the system timers, clock source and clock event.
+ */
+static void __init u300_timer_init(void)
+{
+        u300_enable_timer_clock();
+        /*
+         * 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);
+
+        /* This is a pure microsecond clock source */
+        clocksource_u300_1mhz.mult =
+                clocksource_khz2mult(1000, clocksource_u300_1mhz.shift);
+        if (clocksource_register(&clocksource_u300_1mhz))
+                printk(KERN_ERR "timer: failed to initialize clock "
+                       "source %s\n", clocksource_u300_1mhz.name);
+
+        clockevent_u300_1mhz.mult =
+                div_sc(1000000, NSEC_PER_SEC, clockevent_u300_1mhz.shift);
+        /* 32bit counter, so 32bits delta is max */
+        clockevent_u300_1mhz.max_delta_ns =
+                clockevent_delta2ns(0xffffffff, &clockevent_u300_1mhz);
+        /* This timer is slow enough to set for 1 cycle == 1 MHz */
+        clockevent_u300_1mhz.min_delta_ns =
+                clockevent_delta2ns(1, &clockevent_u300_1mhz);
+        clockevent_u300_1mhz.cpumask = cpumask_of(0);
+        clockevents_register_device(&clockevent_u300_1mhz);
+        /*
+         * 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,
+};