1 files changed, 82 insertions, 413 deletions

diff --git a/arch/x86/kernel/apb_timer.c b/arch/x86/kernel/apb_timer.c
index 92543c73cf8..af5b08ab3b7 100644
--- a/arch/x86/kernel/apb_timer.c
+++ b/arch/x86/kernel/apb_timer.c
@@ -27,15 +27,12 @@
  * timer, but by default APB timer has higher rating than local APIC timers.
  */
 
-#include <linux/clocksource.h>
-#include <linux/clockchips.h>
 #include <linux/delay.h>
+#include <linux/dw_apb_timer.h>
 #include <linux/errno.h>
 #include <linux/init.h>
-#include <linux/sysdev.h>
 #include <linux/slab.h>
 #include <linux/pm.h>
-#include <linux/pci.h>
 #include <linux/sfi.h>
 #include <linux/interrupt.h>
 #include <linux/cpu.h>
@@ -43,77 +40,49 @@
 
 #include <asm/fixmap.h>
 #include <asm/apb_timer.h>
-#include <asm/mrst.h>
+#include <asm/intel-mid.h>
+#include <asm/time.h>
 
-#define APBT_MASK			CLOCKSOURCE_MASK(32)
-#define APBT_SHIFT			22
 #define APBT_CLOCKEVENT_RATING		110
 #define APBT_CLOCKSOURCE_RATING		250
-#define APBT_MIN_DELTA_USEC		200
 
-#define EVT_TO_APBT_DEV(evt) container_of(evt, struct apbt_dev, evt)
 #define APBT_CLOCKEVENT0_NUM   (0)
-#define APBT_CLOCKEVENT1_NUM   (1)
 #define APBT_CLOCKSOURCE_NUM   (2)
 
-static unsigned long apbt_address;
+static phys_addr_t apbt_address;
 static int apb_timer_block_enabled;
 static void __iomem *apbt_virt_address;
-static int phy_cs_timer_id;
 
 /*
  * Common DW APB timer info
  */
-static uint64_t apbt_freq;
-
-static void apbt_set_mode(enum clock_event_mode mode,
-			  struct clock_event_device *evt);
-static int apbt_next_event(unsigned long delta,
-			   struct clock_event_device *evt);
-static cycle_t apbt_read_clocksource(struct clocksource *cs);
-static void apbt_restart_clocksource(struct clocksource *cs);
+static unsigned long apbt_freq;
 
 struct apbt_dev {
-	struct clock_event_device evt;
-	unsigned int num;
-	int cpu;
-	unsigned int irq;
-	unsigned int tick;
-	unsigned int count;
-	unsigned int flags;
-	char name[10];
+	struct dw_apb_clock_event_device	*timer;
+	unsigned int				num;
+	int					cpu;
+	unsigned int				irq;
+	char					name[10];
 };
 
-static DEFINE_PER_CPU(struct apbt_dev, cpu_apbt_dev);
-
-#ifdef CONFIG_SMP
-static unsigned int apbt_num_timers_used;
-static struct apbt_dev *apbt_devs;
-#endif
-
-static	inline unsigned long apbt_readl_reg(unsigned long a)
-{
-	return readl(apbt_virt_address + a);
-}
+static struct dw_apb_clocksource *clocksource_apbt;
 
-static inline void apbt_writel_reg(unsigned long d, unsigned long a)
+static inline void __iomem *adev_virt_addr(struct apbt_dev *adev)
 {
-	writel(d, apbt_virt_address + a);
+	return apbt_virt_address + adev->num * APBTMRS_REG_SIZE;
 }
 
-static inline unsigned long apbt_readl(int n, unsigned long a)
-{
-	return readl(apbt_virt_address + a + n * APBTMRS_REG_SIZE);
-}
+static DEFINE_PER_CPU(struct apbt_dev, cpu_apbt_dev);
 
-static inline void apbt_writel(int n, unsigned long d, unsigned long a)
-{
-	writel(d, apbt_virt_address + a + n * APBTMRS_REG_SIZE);
-}
+#ifdef CONFIG_SMP
+static unsigned int apbt_num_timers_used;
+#endif
 
 static inline void apbt_set_mapping(void)
 {
 	struct sfi_timer_table_entry *mtmr;
+	int phy_cs_timer_id = 0;
 
 	if (apbt_virt_address) {
 		pr_debug("APBT base already mapped\n");
@@ -125,21 +94,18 @@ static inline void apbt_set_mapping(void)
 		       APBT_CLOCKEVENT0_NUM);
 		return;
 	}
-	apbt_address = (unsigned long)mtmr->phys_addr;
+	apbt_address = (phys_addr_t)mtmr->phys_addr;
 	if (!apbt_address) {
 		printk(KERN_WARNING "No timer base from SFI, use default\n");
 		apbt_address = APBT_DEFAULT_BASE;
 	}
 	apbt_virt_address = ioremap_nocache(apbt_address, APBT_MMAP_SIZE);
-	if (apbt_virt_address) {
-		pr_debug("Mapped APBT physical addr %p at virtual addr %p\n",\
-			 (void *)apbt_address, (void *)apbt_virt_address);
-	} else {
-		pr_debug("Failed mapping APBT phy address at %p\n",\
-			 (void *)apbt_address);
+	if (!apbt_virt_address) {
+		pr_debug("Failed mapping APBT phy address at %lu\n",\
+			 (unsigned long)apbt_address);
 		goto panic_noapbt;
 	}
-	apbt_freq = mtmr->freq_hz / USEC_PER_SEC;
+	apbt_freq = mtmr->freq_hz;
 	sfi_free_mtmr(mtmr);
 
 	/* Now figure out the physical timer id for clocksource device */
@@ -148,9 +114,14 @@ static inline void apbt_set_mapping(void)
 		goto panic_noapbt;
 
 	/* Now figure out the physical timer id */
-	phy_cs_timer_id = (unsigned int)(mtmr->phys_addr & 0xff)
-		/ APBTMRS_REG_SIZE;
-	pr_debug("Use timer %d for clocksource\n", phy_cs_timer_id);
+	pr_debug("Use timer %d for clocksource\n",
+		 (int)(mtmr->phys_addr & 0xff) / APBTMRS_REG_SIZE);
+	phy_cs_timer_id = (unsigned int)(mtmr->phys_addr & 0xff) /
+		APBTMRS_REG_SIZE;
+
+	clocksource_apbt = dw_apb_clocksource_init(APBT_CLOCKSOURCE_RATING,
+		"apbt0", apbt_virt_address + phy_cs_timer_id *
+		APBTMRS_REG_SIZE, apbt_freq);
 	return;
 
 panic_noapbt:
@@ -172,83 +143,6 @@ static inline int is_apbt_capable(void)
 	return apbt_virt_address ? 1 : 0;
 }
 
-static struct clocksource clocksource_apbt = {
-	.name		= "apbt",
-	.rating		= APBT_CLOCKSOURCE_RATING,
-	.read		= apbt_read_clocksource,
-	.mask		= APBT_MASK,
-	.shift		= APBT_SHIFT,
-	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
-	.resume		= apbt_restart_clocksource,
-};
-
-/* boot APB clock event device */
-static struct clock_event_device apbt_clockevent = {
-	.name		= "apbt0",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode	= apbt_set_mode,
-	.set_next_event = apbt_next_event,
-	.shift		= APBT_SHIFT,
-	.irq		= 0,
-	.rating		= APBT_CLOCKEVENT_RATING,
-};
-
-/*
- * start count down from 0xffff_ffff. this is done by toggling the enable bit
- * then load initial load count to ~0.
- */
-static void apbt_start_counter(int n)
-{
-	unsigned long ctrl = apbt_readl(n, APBTMR_N_CONTROL);
-
-	ctrl &= ~APBTMR_CONTROL_ENABLE;
-	apbt_writel(n, ctrl, APBTMR_N_CONTROL);
-	apbt_writel(n, ~0, APBTMR_N_LOAD_COUNT);
-	/* enable, mask interrupt */
-	ctrl &= ~APBTMR_CONTROL_MODE_PERIODIC;
-	ctrl |= (APBTMR_CONTROL_ENABLE | APBTMR_CONTROL_INT);
-	apbt_writel(n, ctrl, APBTMR_N_CONTROL);
-	/* read it once to get cached counter value initialized */
-	apbt_read_clocksource(&clocksource_apbt);
-}
-
-static irqreturn_t apbt_interrupt_handler(int irq, void *data)
-{
-	struct apbt_dev *dev = (struct apbt_dev *)data;
-	struct clock_event_device *aevt = &dev->evt;
-
-	if (!aevt->event_handler) {
-		printk(KERN_INFO "Spurious APBT timer interrupt on %d\n",
-		       dev->num);
-		return IRQ_NONE;
-	}
-	aevt->event_handler(aevt);
-	return IRQ_HANDLED;
-}
-
-static void apbt_restart_clocksource(struct clocksource *cs)
-{
-	apbt_start_counter(phy_cs_timer_id);
-}
-
-static void apbt_enable_int(int n)
-{
-	unsigned long ctrl = apbt_readl(n, APBTMR_N_CONTROL);
-	/* clear pending intr */
-	apbt_readl(n, APBTMR_N_EOI);
-	ctrl &= ~APBTMR_CONTROL_INT;
-	apbt_writel(n, ctrl, APBTMR_N_CONTROL);
-}
-
-static void apbt_disable_int(int n)
-{
-	unsigned long ctrl = apbt_readl(n, APBTMR_N_CONTROL);
-
-	ctrl |= APBTMR_CONTROL_INT;
-	apbt_writel(n, ctrl, APBTMR_N_CONTROL);
-}
-
-
 static int __init apbt_clockevent_register(void)
 {
 	struct sfi_timer_table_entry *mtmr;
@@ -261,45 +155,21 @@ static int __init apbt_clockevent_register(void)
 		return -ENODEV;
 	}
 
-	/*
-	 * We need to calculate the scaled math multiplication factor for
-	 * nanosecond to apbt tick conversion.
-	 * mult = (nsec/cycle)*2^APBT_SHIFT
-	 */
-	apbt_clockevent.mult = div_sc((unsigned long) mtmr->freq_hz
-				      , NSEC_PER_SEC, APBT_SHIFT);
-
-	/* Calculate the min / max delta */
-	apbt_clockevent.max_delta_ns = clockevent_delta2ns(0x7FFFFFFF,
-							   &apbt_clockevent);
-	apbt_clockevent.min_delta_ns = clockevent_delta2ns(
-		APBT_MIN_DELTA_USEC*apbt_freq,
-		&apbt_clockevent);
-	/*
-	 * Start apbt with the boot cpu mask and make it
-	 * global if not used for per cpu timer.
-	 */
-	apbt_clockevent.cpumask = cpumask_of(smp_processor_id());
 	adev->num = smp_processor_id();
-	memcpy(&adev->evt, &apbt_clockevent, sizeof(struct clock_event_device));
-
-	if (mrst_timer_options == MRST_TIMER_LAPIC_APBT) {
-		apbt_clockevent.rating = APBT_CLOCKEVENT_RATING - 100;
-		global_clock_event = &adev->evt;
+	adev->timer = dw_apb_clockevent_init(smp_processor_id(), "apbt0",
+		intel_mid_timer_options == INTEL_MID_TIMER_LAPIC_APBT ?
+		APBT_CLOCKEVENT_RATING - 100 : APBT_CLOCKEVENT_RATING,
+		adev_virt_addr(adev), 0, apbt_freq);
+	/* Firmware does EOI handling for us. */
+	adev->timer->eoi = NULL;
+
+	if (intel_mid_timer_options == INTEL_MID_TIMER_LAPIC_APBT) {
+		global_clock_event = &adev->timer->ced;
 		printk(KERN_DEBUG "%s clockevent registered as global\n",
 		       global_clock_event->name);
 	}
 
-	if (request_irq(apbt_clockevent.irq, apbt_interrupt_handler,
-			IRQF_TIMER | IRQF_DISABLED | IRQF_NOBALANCING,
-			apbt_clockevent.name, adev)) {
-		printk(KERN_ERR "Failed request IRQ for APBT%d\n",
-		       apbt_clockevent.irq);
-	}
-
-	clockevents_register_device(&adev->evt);
-	/* Start APBT 0 interrupts */
-	apbt_enable_int(APBT_CLOCKEVENT0_NUM);
+	dw_apb_clockevent_register(adev->timer);
 
 	sfi_free_mtmr(mtmr);
 	return 0;
@@ -313,53 +183,38 @@ static void apbt_setup_irq(struct apbt_dev *adev)
 	if (adev->irq == 0)
 		return;
 
-	if (system_state == SYSTEM_BOOTING) {
-		irq_modify_status(adev->irq, 0, IRQ_MOVE_PCNTXT);
-		/* APB timer irqs are set up as mp_irqs, timer is edge type */
-		__set_irq_handler(adev->irq, handle_edge_irq, 0, "edge");
-		if (request_irq(adev->irq, apbt_interrupt_handler,
-				IRQF_TIMER | IRQF_DISABLED | IRQF_NOBALANCING,
-				adev->name, adev)) {
-			printk(KERN_ERR "Failed request IRQ for APBT%d\n",
-			       adev->num);
-		}
-	} else
-		enable_irq(adev->irq);
+	irq_modify_status(adev->irq, 0, IRQ_MOVE_PCNTXT);
+	irq_set_affinity(adev->irq, cpumask_of(adev->cpu));
+	/* APB timer irqs are set up as mp_irqs, timer is edge type */
+	__irq_set_handler(adev->irq, handle_edge_irq, 0, "edge");
 }
 
 /* Should be called with per cpu */
 void apbt_setup_secondary_clock(void)
 {
 	struct apbt_dev *adev;
-	struct clock_event_device *aevt;
 	int cpu;
 
 	/* Don't register boot CPU clockevent */
 	cpu = smp_processor_id();
 	if (!cpu)
 		return;
-	/*
-	 * We need to calculate the scaled math multiplication factor for
-	 * nanosecond to apbt tick conversion.
-	 * mult = (nsec/cycle)*2^APBT_SHIFT
-	 */
-	printk(KERN_INFO "Init per CPU clockevent %d\n", cpu);
-	adev = &per_cpu(cpu_apbt_dev, cpu);
-	aevt = &adev->evt;
 
-	memcpy(aevt, &apbt_clockevent, sizeof(*aevt));
-	aevt->cpumask = cpumask_of(cpu);
-	aevt->name = adev->name;
-	aevt->mode = CLOCK_EVT_MODE_UNUSED;
+	adev = &__get_cpu_var(cpu_apbt_dev);
+	if (!adev->timer) {
+		adev->timer = dw_apb_clockevent_init(cpu, adev->name,
+			APBT_CLOCKEVENT_RATING, adev_virt_addr(adev),
+			adev->irq, apbt_freq);
+		adev->timer->eoi = NULL;
+	} else {
+		dw_apb_clockevent_resume(adev->timer);
+	}
 
-	printk(KERN_INFO "Registering CPU %d clockevent device %s, mask %08x\n",
-	       cpu, aevt->name, *(u32 *)aevt->cpumask);
+	printk(KERN_INFO "Registering CPU %d clockevent device %s, cpu %08x\n",
+	       cpu, adev->name, adev->cpu);
 
 	apbt_setup_irq(adev);
-
-	clockevents_register_device(aevt);
-
-	apbt_enable_int(cpu);
+	dw_apb_clockevent_register(adev->timer);
 
 	return;
 }
@@ -382,13 +237,12 @@ static int apbt_cpuhp_notify(struct notifier_block *n,
 
 	switch (action & 0xf) {
 	case CPU_DEAD:
-		disable_irq(adev->irq);
-		apbt_disable_int(cpu);
+		dw_apb_clockevent_pause(adev->timer);
 		if (system_state == SYSTEM_RUNNING) {
 			pr_debug("skipping APBT CPU %lu offline\n", cpu);
-		} else if (adev) {
+		} else {
 			pr_debug("APBT clockevent for cpu %lu offline\n", cpu);
-			free_irq(adev->irq, adev);
+			dw_apb_clockevent_stop(adev->timer);
 		}
 		break;
 	default:
@@ -399,7 +253,7 @@ static int apbt_cpuhp_notify(struct notifier_block *n,
 
 static __init int apbt_late_init(void)
 {
-	if (mrst_timer_options == MRST_TIMER_LAPIC_APBT ||
+	if (intel_mid_timer_options == INTEL_MID_TIMER_LAPIC_APBT ||
 		!apb_timer_block_enabled)
 		return 0;
 	/* This notifier should be called after workqueue is ready */
@@ -413,168 +267,16 @@ void apbt_setup_secondary_clock(void) {}
 
 #endif /* CONFIG_SMP */
 
-static void apbt_set_mode(enum clock_event_mode mode,
-			  struct clock_event_device *evt)
-{
-	unsigned long ctrl;
-	uint64_t delta;
-	int timer_num;
-	struct apbt_dev *adev = EVT_TO_APBT_DEV(evt);
-
-	BUG_ON(!apbt_virt_address);
-
-	timer_num = adev->num;
-	pr_debug("%s CPU %d timer %d mode=%d\n",
-		 __func__, first_cpu(*evt->cpumask), timer_num, mode);
-
-	switch (mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * apbt_clockevent.mult;
-		delta >>= apbt_clockevent.shift;
-		ctrl = apbt_readl(timer_num, APBTMR_N_CONTROL);
-		ctrl |= APBTMR_CONTROL_MODE_PERIODIC;
-		apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-		/*
-		 * DW APB p. 46, have to disable timer before load counter,
-		 * may cause sync problem.
-		 */
-		ctrl &= ~APBTMR_CONTROL_ENABLE;
-		apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-		udelay(1);
-		pr_debug("Setting clock period %d for HZ %d\n", (int)delta, HZ);
-		apbt_writel(timer_num, delta, APBTMR_N_LOAD_COUNT);
-		ctrl |= APBTMR_CONTROL_ENABLE;
-		apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-		break;
-		/* APB timer does not have one-shot mode, use free running mode */
-	case CLOCK_EVT_MODE_ONESHOT:
-		ctrl = apbt_readl(timer_num, APBTMR_N_CONTROL);
-		/*
-		 * set free running mode, this mode will let timer reload max
-		 * timeout which will give time (3min on 25MHz clock) to rearm
-		 * the next event, therefore emulate the one-shot mode.
-		 */
-		ctrl &= ~APBTMR_CONTROL_ENABLE;
-		ctrl &= ~APBTMR_CONTROL_MODE_PERIODIC;
-
-		apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-		/* write again to set free running mode */
-		apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-
-		/*
-		 * DW APB p. 46, load counter with all 1s before starting free
-		 * running mode.
-		 */
-		apbt_writel(timer_num, ~0, APBTMR_N_LOAD_COUNT);
-		ctrl &= ~APBTMR_CONTROL_INT;
-		ctrl |= APBTMR_CONTROL_ENABLE;
-		apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-		break;
-
-	case CLOCK_EVT_MODE_UNUSED:
-	case CLOCK_EVT_MODE_SHUTDOWN:
-		apbt_disable_int(timer_num);
-		ctrl = apbt_readl(timer_num, APBTMR_N_CONTROL);
-		ctrl &= ~APBTMR_CONTROL_ENABLE;
-		apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-		break;
-
-	case CLOCK_EVT_MODE_RESUME:
-		apbt_enable_int(timer_num);
-		break;
-	}
-}
-
-static int apbt_next_event(unsigned long delta,
-			   struct clock_event_device *evt)
-{
-	unsigned long ctrl;
-	int timer_num;
-
-	struct apbt_dev *adev = EVT_TO_APBT_DEV(evt);
-
-	timer_num = adev->num;
-	/* Disable timer */
-	ctrl = apbt_readl(timer_num, APBTMR_N_CONTROL);
-	ctrl &= ~APBTMR_CONTROL_ENABLE;
-	apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-	/* write new count */
-	apbt_writel(timer_num, delta, APBTMR_N_LOAD_COUNT);
-	ctrl |= APBTMR_CONTROL_ENABLE;
-	apbt_writel(timer_num, ctrl, APBTMR_N_CONTROL);
-	return 0;
-}
-
-/*
- * APB timer clock is not in sync with pclk on Langwell, which translates to
- * unreliable read value caused by sampling error. the error does not add up
- * overtime and only happens when sampling a 0 as a 1 by mistake. so the time
- * would go backwards. the following code is trying to prevent time traveling
- * backwards. little bit paranoid.
- */
-static cycle_t apbt_read_clocksource(struct clocksource *cs)
-{
-	unsigned long t0, t1, t2;
-	static unsigned long last_read;
-
-bad_count:
-	t1 = apbt_readl(phy_cs_timer_id,
-			APBTMR_N_CURRENT_VALUE);
-	t2 = apbt_readl(phy_cs_timer_id,
-			APBTMR_N_CURRENT_VALUE);
-	if (unlikely(t1 < t2)) {
-		pr_debug("APBT: read current count error %lx:%lx:%lx\n",
-			 t1, t2, t2 - t1);
-		goto bad_count;
-	}
-	/*
-	 * check against cached last read, makes sure time does not go back.
-	 * it could be a normal rollover but we will do tripple check anyway
-	 */
-	if (unlikely(t2 > last_read)) {
-		/* check if we have a normal rollover */
-		unsigned long raw_intr_status =
-			apbt_readl_reg(APBTMRS_RAW_INT_STATUS);
-		/*
-		 * cs timer interrupt is masked but raw intr bit is set if
-		 * rollover occurs. then we read EOI reg to clear it.
-		 */
-		if (raw_intr_status & (1 << phy_cs_timer_id)) {
-			apbt_readl(phy_cs_timer_id, APBTMR_N_EOI);
-			goto out;
-		}
-		pr_debug("APB CS going back %lx:%lx:%lx ",
-			 t2, last_read, t2 - last_read);
-bad_count_x3:
-		pr_debug("triple check enforced\n");
-		t0 = apbt_readl(phy_cs_timer_id,
-				APBTMR_N_CURRENT_VALUE);
-		udelay(1);
-		t1 = apbt_readl(phy_cs_timer_id,
-				APBTMR_N_CURRENT_VALUE);
-		udelay(1);
-		t2 = apbt_readl(phy_cs_timer_id,
-				APBTMR_N_CURRENT_VALUE);
-		if ((t2 > t1) || (t1 > t0)) {
-			printk(KERN_ERR "Error: APB CS tripple check failed\n");
-			goto bad_count_x3;
-		}
-	}
-out:
-	last_read = t2;
-	return (cycle_t)~t2;
-}
-
 static int apbt_clocksource_register(void)
 {
 	u64 start, now;
 	cycle_t t1;
 
 	/* Start the counter, use timer 2 as source, timer 0/1 for event */
-	apbt_start_counter(phy_cs_timer_id);
+	dw_apb_clocksource_start(clocksource_apbt);
 
 	/* Verify whether apbt counter works */
-	t1 = apbt_read_clocksource(&clocksource_apbt);
+	t1 = dw_apb_clocksource_read(clocksource_apbt);
 	rdtscll(start);
 
 	/*
@@ -589,17 +291,10 @@ static int apbt_clocksource_register(void)
 	} while ((now - start) < 200000UL);
 
 	/* APBT is the only always on clocksource, it has to work! */
-	if (t1 == apbt_read_clocksource(&clocksource_apbt))
+	if (t1 == dw_apb_clocksource_read(clocksource_apbt))
 		panic("APBT counter not counting. APBT disabled\n");
 
-	/*
-	 * initialize and register APBT clocksource
-	 * convert that to ns/clock cycle
-	 * mult = (ns/c) * 2^APBT_SHIFT
-	 */
-	clocksource_apbt.mult = div_sc(MSEC_PER_SEC,
-				       (unsigned long) apbt_freq, APBT_SHIFT);
-	clocksource_register(&clocksource_apbt);
+	dw_apb_clocksource_register(clocksource_apbt);
 
 	return 0;
 }
@@ -616,17 +311,13 @@ void __init apbt_time_init(void)
 #ifdef CONFIG_SMP
 	int i;
 	struct sfi_timer_table_entry *p_mtmr;
-	unsigned int percpu_timer;
 	struct apbt_dev *adev;
 #endif
 
 	if (apb_timer_block_enabled)
 		return;
 	apbt_set_mapping();
-	if (apbt_virt_address) {
-		pr_debug("Found APBT version 0x%lx\n",\
-			 apbt_readl_reg(APBTMRS_COMP_VERSION));
-	} else
+	if (!apbt_virt_address)
 		goto out_noapbt;
 	/*
 	 * Read the frequency and check for a sane value, for ESL model
@@ -634,7 +325,7 @@ void __init apbt_time_init(void)
 	 */
 
 	if (apbt_freq < APBT_MIN_FREQ || apbt_freq > APBT_MAX_FREQ) {
-		pr_debug("APBT has invalid freq 0x%llx\n", apbt_freq);
+		pr_debug("APBT has invalid freq 0x%lx\n", apbt_freq);
 		goto out_noapbt;
 	}
 	if (apbt_clocksource_register()) {
@@ -649,41 +340,28 @@ void __init apbt_time_init(void)
 	}
 #ifdef CONFIG_SMP
 	/* kernel cmdline disable apb timer, so we will use lapic timers */
-	if (mrst_timer_options == MRST_TIMER_LAPIC_APBT) {
+	if (intel_mid_timer_options == INTEL_MID_TIMER_LAPIC_APBT) {
 		printk(KERN_INFO "apbt: disabled per cpu timer\n");
 		return;
 	}
 	pr_debug("%s: %d CPUs online\n", __func__, num_online_cpus());
-	if (num_possible_cpus() <= sfi_mtimer_num) {
-		percpu_timer = 1;
+	if (num_possible_cpus() <= sfi_mtimer_num)
 		apbt_num_timers_used = num_possible_cpus();
-	} else {
-		percpu_timer = 0;
+	else
 		apbt_num_timers_used = 1;
-		adev = &per_cpu(cpu_apbt_dev, 0);
-		adev->flags &= ~APBT_DEV_USED;
-	}
 	pr_debug("%s: %d APB timers used\n", __func__, apbt_num_timers_used);
 
 	/* here we set up per CPU timer data structure */
-	apbt_devs = kzalloc(sizeof(struct apbt_dev) * apbt_num_timers_used,
-			    GFP_KERNEL);
-	if (!apbt_devs) {
-		printk(KERN_ERR "Failed to allocate APB timer devices\n");
-		return;
-	}
 	for (i = 0; i < apbt_num_timers_used; i++) {
 		adev = &per_cpu(cpu_apbt_dev, i);
 		adev->num = i;
 		adev->cpu = i;
 		p_mtmr = sfi_get_mtmr(i);
-		if (p_mtmr) {
-			adev->tick = p_mtmr->freq_hz;
+		if (p_mtmr)
 			adev->irq = p_mtmr->irq;
-		} else
+		else
 			printk(KERN_ERR "Failed to get timer for cpu %d\n", i);
-		adev->count = 0;
-		sprintf(adev->name, "apbt%d", i);
+		snprintf(adev->name, sizeof(adev->name) - 1, "apbt%d", i);
 	}
 #endif
 
@@ -695,17 +373,8 @@ out_noapbt:
 	panic("failed to enable APB timer\n");
 }
 
-static inline void apbt_disable(int n)
-{
-	if (is_apbt_capable()) {
-		unsigned long ctrl =  apbt_readl(n, APBTMR_N_CONTROL);
-		ctrl &= ~APBTMR_CONTROL_ENABLE;
-		apbt_writel(n, ctrl, APBTMR_N_CONTROL);
-	}
-}
-
 /* called before apb_timer_enable, use early map */
-unsigned long apbt_quick_calibrate()
+unsigned long apbt_quick_calibrate(void)
 {
 	int i, scale;
 	u64 old, new;
@@ -714,31 +383,31 @@ unsigned long apbt_quick_calibrate()
 	u32 loop, shift;
 
 	apbt_set_mapping();
-	apbt_start_counter(phy_cs_timer_id);
+	dw_apb_clocksource_start(clocksource_apbt);
 
 	/* check if the timer can count down, otherwise return */
-	old = apbt_read_clocksource(&clocksource_apbt);
+	old = dw_apb_clocksource_read(clocksource_apbt);
 	i = 10000;
 	while (--i) {
-		if (old != apbt_read_clocksource(&clocksource_apbt))
+		if (old != dw_apb_clocksource_read(clocksource_apbt))
 			break;
 	}
 	if (!i)
 		goto failed;
 
 	/* count 16 ms */
-	loop = (apbt_freq * 1000) << 4;
+	loop = (apbt_freq / 1000) << 4;
 
 	/* restart the timer to ensure it won't get to 0 in the calibration */
-	apbt_start_counter(phy_cs_timer_id);
+	dw_apb_clocksource_start(clocksource_apbt);
 
-	old = apbt_read_clocksource(&clocksource_apbt);
+	old = dw_apb_clocksource_read(clocksource_apbt);
 	old += loop;
 
 	t1 = __native_read_tsc();
 
 	do {
-		new = apbt_read_clocksource(&clocksource_apbt);
+		new = dw_apb_clocksource_read(clocksource_apbt);
 	} while (new < old);
 
 	t2 = __native_read_tsc();
@@ -750,7 +419,7 @@ unsigned long apbt_quick_calibrate()
 		return 0;
 	}
 	scale = (int)div_u64((t2 - t1), loop >> shift);
-	khz = (scale * apbt_freq * 1000) >> shift;
+	khz = (scale * (apbt_freq / 1000)) >> shift;
 	printk(KERN_INFO "TSC freq calculated by APB timer is %lu khz\n", khz);
 	return khz;
 failed: