| /* | 
 |  * Timer device implementation for SGI SN platforms. | 
 |  * | 
 |  * This file is subject to the terms and conditions of the GNU General Public | 
 |  * License.  See the file "COPYING" in the main directory of this archive | 
 |  * for more details. | 
 |  * | 
 |  * Copyright (c) 2001-2006 Silicon Graphics, Inc.  All rights reserved. | 
 |  * | 
 |  * This driver exports an API that should be supportable by any HPET or IA-PC | 
 |  * multimedia timer.  The code below is currently specific to the SGI Altix | 
 |  * SHub RTC, however. | 
 |  * | 
 |  * 11/01/01 - jbarnes - initial revision | 
 |  * 9/10/04 - Christoph Lameter - remove interrupt support for kernel inclusion | 
 |  * 10/1/04 - Christoph Lameter - provide posix clock CLOCK_SGI_CYCLE | 
 |  * 10/13/04 - Christoph Lameter, Dimitri Sivanich - provide timer interrupt | 
 |  *		support via the posix timer interface | 
 |  */ | 
 |  | 
 | #include <linux/types.h> | 
 | #include <linux/kernel.h> | 
 | #include <linux/ioctl.h> | 
 | #include <linux/module.h> | 
 | #include <linux/init.h> | 
 | #include <linux/errno.h> | 
 | #include <linux/mm.h> | 
 | #include <linux/mmtimer.h> | 
 | #include <linux/miscdevice.h> | 
 | #include <linux/posix-timers.h> | 
 | #include <linux/interrupt.h> | 
 |  | 
 | #include <asm/uaccess.h> | 
 | #include <asm/sn/addrs.h> | 
 | #include <asm/sn/intr.h> | 
 | #include <asm/sn/shub_mmr.h> | 
 | #include <asm/sn/nodepda.h> | 
 | #include <asm/sn/shubio.h> | 
 |  | 
 | MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>"); | 
 | MODULE_DESCRIPTION("SGI Altix RTC Timer"); | 
 | MODULE_LICENSE("GPL"); | 
 |  | 
 | /* name of the device, usually in /dev */ | 
 | #define MMTIMER_NAME "mmtimer" | 
 | #define MMTIMER_DESC "SGI Altix RTC Timer" | 
 | #define MMTIMER_VERSION "2.1" | 
 |  | 
 | #define RTC_BITS 55 /* 55 bits for this implementation */ | 
 |  | 
 | extern unsigned long sn_rtc_cycles_per_second; | 
 |  | 
 | #define RTC_COUNTER_ADDR        ((long *)LOCAL_MMR_ADDR(SH_RTC)) | 
 |  | 
 | #define rtc_time()              (*RTC_COUNTER_ADDR) | 
 |  | 
 | static int mmtimer_ioctl(struct inode *inode, struct file *file, | 
 | 			 unsigned int cmd, unsigned long arg); | 
 | static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma); | 
 |  | 
 | /* | 
 |  * Period in femtoseconds (10^-15 s) | 
 |  */ | 
 | static unsigned long mmtimer_femtoperiod = 0; | 
 |  | 
 | static const struct file_operations mmtimer_fops = { | 
 | 	.owner =	THIS_MODULE, | 
 | 	.mmap =		mmtimer_mmap, | 
 | 	.ioctl =	mmtimer_ioctl, | 
 | }; | 
 |  | 
 | /* | 
 |  * We only have comparison registers RTC1-4 currently available per | 
 |  * node.  RTC0 is used by SAL. | 
 |  */ | 
 | #define NUM_COMPARATORS 3 | 
 | /* Check for an RTC interrupt pending */ | 
 | static int inline mmtimer_int_pending(int comparator) | 
 | { | 
 | 	if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED)) & | 
 | 			SH_EVENT_OCCURRED_RTC1_INT_MASK << comparator) | 
 | 		return 1; | 
 | 	else | 
 | 		return 0; | 
 | } | 
 | /* Clear the RTC interrupt pending bit */ | 
 | static void inline mmtimer_clr_int_pending(int comparator) | 
 | { | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS), | 
 | 		SH_EVENT_OCCURRED_RTC1_INT_MASK << comparator); | 
 | } | 
 |  | 
 | /* Setup timer on comparator RTC1 */ | 
 | static void inline mmtimer_setup_int_0(u64 expires) | 
 | { | 
 | 	u64 val; | 
 |  | 
 | 	/* Disable interrupt */ | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 0UL); | 
 |  | 
 | 	/* Initialize comparator value */ | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), -1L); | 
 |  | 
 | 	/* Clear pending bit */ | 
 | 	mmtimer_clr_int_pending(0); | 
 |  | 
 | 	val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC1_INT_CONFIG_IDX_SHFT) | | 
 | 		((u64)cpu_physical_id(smp_processor_id()) << | 
 | 			SH_RTC1_INT_CONFIG_PID_SHFT); | 
 |  | 
 | 	/* Set configuration */ | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_CONFIG), val); | 
 |  | 
 | 	/* Enable RTC interrupts */ | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 1UL); | 
 |  | 
 | 	/* Initialize comparator value */ | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), expires); | 
 |  | 
 |  | 
 | } | 
 |  | 
 | /* Setup timer on comparator RTC2 */ | 
 | static void inline mmtimer_setup_int_1(u64 expires) | 
 | { | 
 | 	u64 val; | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 0UL); | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), -1L); | 
 |  | 
 | 	mmtimer_clr_int_pending(1); | 
 |  | 
 | 	val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC2_INT_CONFIG_IDX_SHFT) | | 
 | 		((u64)cpu_physical_id(smp_processor_id()) << | 
 | 			SH_RTC2_INT_CONFIG_PID_SHFT); | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_CONFIG), val); | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 1UL); | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), expires); | 
 | } | 
 |  | 
 | /* Setup timer on comparator RTC3 */ | 
 | static void inline mmtimer_setup_int_2(u64 expires) | 
 | { | 
 | 	u64 val; | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 0UL); | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), -1L); | 
 |  | 
 | 	mmtimer_clr_int_pending(2); | 
 |  | 
 | 	val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC3_INT_CONFIG_IDX_SHFT) | | 
 | 		((u64)cpu_physical_id(smp_processor_id()) << | 
 | 			SH_RTC3_INT_CONFIG_PID_SHFT); | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_CONFIG), val); | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 1UL); | 
 |  | 
 | 	HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), expires); | 
 | } | 
 |  | 
 | /* | 
 |  * This function must be called with interrupts disabled and preemption off | 
 |  * in order to insure that the setup succeeds in a deterministic time frame. | 
 |  * It will check if the interrupt setup succeeded. | 
 |  */ | 
 | static int inline mmtimer_setup(int comparator, unsigned long expires) | 
 | { | 
 |  | 
 | 	switch (comparator) { | 
 | 	case 0: | 
 | 		mmtimer_setup_int_0(expires); | 
 | 		break; | 
 | 	case 1: | 
 | 		mmtimer_setup_int_1(expires); | 
 | 		break; | 
 | 	case 2: | 
 | 		mmtimer_setup_int_2(expires); | 
 | 		break; | 
 | 	} | 
 | 	/* We might've missed our expiration time */ | 
 | 	if (rtc_time() < expires) | 
 | 		return 1; | 
 |  | 
 | 	/* | 
 | 	 * If an interrupt is already pending then its okay | 
 | 	 * if not then we failed | 
 | 	 */ | 
 | 	return mmtimer_int_pending(comparator); | 
 | } | 
 |  | 
 | static int inline mmtimer_disable_int(long nasid, int comparator) | 
 | { | 
 | 	switch (comparator) { | 
 | 	case 0: | 
 | 		nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), | 
 | 			0UL) : REMOTE_HUB_S(nasid, SH_RTC1_INT_ENABLE, 0UL); | 
 | 		break; | 
 | 	case 1: | 
 | 		nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), | 
 | 			0UL) : REMOTE_HUB_S(nasid, SH_RTC2_INT_ENABLE, 0UL); | 
 | 		break; | 
 | 	case 2: | 
 | 		nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), | 
 | 			0UL) : REMOTE_HUB_S(nasid, SH_RTC3_INT_ENABLE, 0UL); | 
 | 		break; | 
 | 	default: | 
 | 		return -EFAULT; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | #define TIMER_OFF 0xbadcabLL | 
 |  | 
 | /* There is one of these for each comparator */ | 
 | typedef struct mmtimer { | 
 | 	spinlock_t lock ____cacheline_aligned; | 
 | 	struct k_itimer *timer; | 
 | 	int i; | 
 | 	int cpu; | 
 | 	struct tasklet_struct tasklet; | 
 | } mmtimer_t; | 
 |  | 
 | static mmtimer_t ** timers; | 
 |  | 
 | /** | 
 |  * mmtimer_ioctl - ioctl interface for /dev/mmtimer | 
 |  * @inode: inode of the device | 
 |  * @file: file structure for the device | 
 |  * @cmd: command to execute | 
 |  * @arg: optional argument to command | 
 |  * | 
 |  * Executes the command specified by @cmd.  Returns 0 for success, < 0 for | 
 |  * failure. | 
 |  * | 
 |  * Valid commands: | 
 |  * | 
 |  * %MMTIMER_GETOFFSET - Should return the offset (relative to the start | 
 |  * of the page where the registers are mapped) for the counter in question. | 
 |  * | 
 |  * %MMTIMER_GETRES - Returns the resolution of the clock in femto (10^-15) | 
 |  * seconds | 
 |  * | 
 |  * %MMTIMER_GETFREQ - Copies the frequency of the clock in Hz to the address | 
 |  * specified by @arg | 
 |  * | 
 |  * %MMTIMER_GETBITS - Returns the number of bits in the clock's counter | 
 |  * | 
 |  * %MMTIMER_MMAPAVAIL - Returns 1 if the registers can be mmap'd into userspace | 
 |  * | 
 |  * %MMTIMER_GETCOUNTER - Gets the current value in the counter and places it | 
 |  * in the address specified by @arg. | 
 |  */ | 
 | static int mmtimer_ioctl(struct inode *inode, struct file *file, | 
 | 			 unsigned int cmd, unsigned long arg) | 
 | { | 
 | 	int ret = 0; | 
 |  | 
 | 	switch (cmd) { | 
 | 	case MMTIMER_GETOFFSET:	/* offset of the counter */ | 
 | 		/* | 
 | 		 * SN RTC registers are on their own 64k page | 
 | 		 */ | 
 | 		if(PAGE_SIZE <= (1 << 16)) | 
 | 			ret = (((long)RTC_COUNTER_ADDR) & (PAGE_SIZE-1)) / 8; | 
 | 		else | 
 | 			ret = -ENOSYS; | 
 | 		break; | 
 |  | 
 | 	case MMTIMER_GETRES: /* resolution of the clock in 10^-15 s */ | 
 | 		if(copy_to_user((unsigned long __user *)arg, | 
 | 				&mmtimer_femtoperiod, sizeof(unsigned long))) | 
 | 			return -EFAULT; | 
 | 		break; | 
 |  | 
 | 	case MMTIMER_GETFREQ: /* frequency in Hz */ | 
 | 		if(copy_to_user((unsigned long __user *)arg, | 
 | 				&sn_rtc_cycles_per_second, | 
 | 				sizeof(unsigned long))) | 
 | 			return -EFAULT; | 
 | 		ret = 0; | 
 | 		break; | 
 |  | 
 | 	case MMTIMER_GETBITS: /* number of bits in the clock */ | 
 | 		ret = RTC_BITS; | 
 | 		break; | 
 |  | 
 | 	case MMTIMER_MMAPAVAIL: /* can we mmap the clock into userspace? */ | 
 | 		ret = (PAGE_SIZE <= (1 << 16)) ? 1 : 0; | 
 | 		break; | 
 |  | 
 | 	case MMTIMER_GETCOUNTER: | 
 | 		if(copy_to_user((unsigned long __user *)arg, | 
 | 				RTC_COUNTER_ADDR, sizeof(unsigned long))) | 
 | 			return -EFAULT; | 
 | 		break; | 
 | 	default: | 
 | 		ret = -ENOSYS; | 
 | 		break; | 
 | 	} | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | /** | 
 |  * mmtimer_mmap - maps the clock's registers into userspace | 
 |  * @file: file structure for the device | 
 |  * @vma: VMA to map the registers into | 
 |  * | 
 |  * Calls remap_pfn_range() to map the clock's registers into | 
 |  * the calling process' address space. | 
 |  */ | 
 | static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma) | 
 | { | 
 | 	unsigned long mmtimer_addr; | 
 |  | 
 | 	if (vma->vm_end - vma->vm_start != PAGE_SIZE) | 
 | 		return -EINVAL; | 
 |  | 
 | 	if (vma->vm_flags & VM_WRITE) | 
 | 		return -EPERM; | 
 |  | 
 | 	if (PAGE_SIZE > (1 << 16)) | 
 | 		return -ENOSYS; | 
 |  | 
 | 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); | 
 |  | 
 | 	mmtimer_addr = __pa(RTC_COUNTER_ADDR); | 
 | 	mmtimer_addr &= ~(PAGE_SIZE - 1); | 
 | 	mmtimer_addr &= 0xfffffffffffffffUL; | 
 |  | 
 | 	if (remap_pfn_range(vma, vma->vm_start, mmtimer_addr >> PAGE_SHIFT, | 
 | 					PAGE_SIZE, vma->vm_page_prot)) { | 
 | 		printk(KERN_ERR "remap_pfn_range failed in mmtimer.c\n"); | 
 | 		return -EAGAIN; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static struct miscdevice mmtimer_miscdev = { | 
 | 	SGI_MMTIMER, | 
 | 	MMTIMER_NAME, | 
 | 	&mmtimer_fops | 
 | }; | 
 |  | 
 | static struct timespec sgi_clock_offset; | 
 | static int sgi_clock_period; | 
 |  | 
 | /* | 
 |  * Posix Timer Interface | 
 |  */ | 
 |  | 
 | static struct timespec sgi_clock_offset; | 
 | static int sgi_clock_period; | 
 |  | 
 | static int sgi_clock_get(clockid_t clockid, struct timespec *tp) | 
 | { | 
 | 	u64 nsec; | 
 |  | 
 | 	nsec = rtc_time() * sgi_clock_period | 
 | 			+ sgi_clock_offset.tv_nsec; | 
 | 	tp->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &tp->tv_nsec) | 
 | 			+ sgi_clock_offset.tv_sec; | 
 | 	return 0; | 
 | }; | 
 |  | 
 | static int sgi_clock_set(clockid_t clockid, struct timespec *tp) | 
 | { | 
 |  | 
 | 	u64 nsec; | 
 | 	u64 rem; | 
 |  | 
 | 	nsec = rtc_time() * sgi_clock_period; | 
 |  | 
 | 	sgi_clock_offset.tv_sec = tp->tv_sec - div_long_long_rem(nsec, NSEC_PER_SEC, &rem); | 
 |  | 
 | 	if (rem <= tp->tv_nsec) | 
 | 		sgi_clock_offset.tv_nsec = tp->tv_sec - rem; | 
 | 	else { | 
 | 		sgi_clock_offset.tv_nsec = tp->tv_sec + NSEC_PER_SEC - rem; | 
 | 		sgi_clock_offset.tv_sec--; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | /* | 
 |  * Schedule the next periodic interrupt. This function will attempt | 
 |  * to schedule a periodic interrupt later if necessary. If the scheduling | 
 |  * of an interrupt fails then the time to skip is lengthened | 
 |  * exponentially in order to ensure that the next interrupt | 
 |  * can be properly scheduled.. | 
 |  */ | 
 | static int inline reschedule_periodic_timer(mmtimer_t *x) | 
 | { | 
 | 	int n; | 
 | 	struct k_itimer *t = x->timer; | 
 |  | 
 | 	t->it.mmtimer.clock = x->i; | 
 | 	t->it_overrun--; | 
 |  | 
 | 	n = 0; | 
 | 	do { | 
 |  | 
 | 		t->it.mmtimer.expires += t->it.mmtimer.incr << n; | 
 | 		t->it_overrun += 1 << n; | 
 | 		n++; | 
 | 		if (n > 20) | 
 | 			return 1; | 
 |  | 
 | 	} while (!mmtimer_setup(x->i, t->it.mmtimer.expires)); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | /** | 
 |  * mmtimer_interrupt - timer interrupt handler | 
 |  * @irq: irq received | 
 |  * @dev_id: device the irq came from | 
 |  * | 
 |  * Called when one of the comarators matches the counter, This | 
 |  * routine will send signals to processes that have requested | 
 |  * them. | 
 |  * | 
 |  * This interrupt is run in an interrupt context | 
 |  * by the SHUB. It is therefore safe to locally access SHub | 
 |  * registers. | 
 |  */ | 
 | static irqreturn_t | 
 | mmtimer_interrupt(int irq, void *dev_id) | 
 | { | 
 | 	int i; | 
 | 	unsigned long expires = 0; | 
 | 	int result = IRQ_NONE; | 
 | 	unsigned indx = cpu_to_node(smp_processor_id()); | 
 |  | 
 | 	/* | 
 | 	 * Do this once for each comparison register | 
 | 	 */ | 
 | 	for (i = 0; i < NUM_COMPARATORS; i++) { | 
 | 		mmtimer_t *base = timers[indx] + i; | 
 | 		/* Make sure this doesn't get reused before tasklet_sched */ | 
 | 		spin_lock(&base->lock); | 
 | 		if (base->cpu == smp_processor_id()) { | 
 | 			if (base->timer) | 
 | 				expires = base->timer->it.mmtimer.expires; | 
 | 			/* expires test won't work with shared irqs */ | 
 | 			if ((mmtimer_int_pending(i) > 0) || | 
 | 				(expires && (expires < rtc_time()))) { | 
 | 				mmtimer_clr_int_pending(i); | 
 | 				tasklet_schedule(&base->tasklet); | 
 | 				result = IRQ_HANDLED; | 
 | 			} | 
 | 		} | 
 | 		spin_unlock(&base->lock); | 
 | 		expires = 0; | 
 | 	} | 
 | 	return result; | 
 | } | 
 |  | 
 | void mmtimer_tasklet(unsigned long data) { | 
 | 	mmtimer_t *x = (mmtimer_t *)data; | 
 | 	struct k_itimer *t = x->timer; | 
 | 	unsigned long flags; | 
 |  | 
 | 	if (t == NULL) | 
 | 		return; | 
 |  | 
 | 	/* Send signal and deal with periodic signals */ | 
 | 	spin_lock_irqsave(&t->it_lock, flags); | 
 | 	spin_lock(&x->lock); | 
 | 	/* If timer was deleted between interrupt and here, leave */ | 
 | 	if (t != x->timer) | 
 | 		goto out; | 
 | 	t->it_overrun = 0; | 
 |  | 
 | 	if (posix_timer_event(t, 0) != 0) { | 
 |  | 
 | 		// printk(KERN_WARNING "mmtimer: cannot deliver signal.\n"); | 
 |  | 
 | 		t->it_overrun++; | 
 | 	} | 
 | 	if(t->it.mmtimer.incr) { | 
 | 		/* Periodic timer */ | 
 | 		if (reschedule_periodic_timer(x)) { | 
 | 			printk(KERN_WARNING "mmtimer: unable to reschedule\n"); | 
 | 			x->timer = NULL; | 
 | 		} | 
 | 	} else { | 
 | 		/* Ensure we don't false trigger in mmtimer_interrupt */ | 
 | 		t->it.mmtimer.expires = 0; | 
 | 	} | 
 | 	t->it_overrun_last = t->it_overrun; | 
 | out: | 
 | 	spin_unlock(&x->lock); | 
 | 	spin_unlock_irqrestore(&t->it_lock, flags); | 
 | } | 
 |  | 
 | static int sgi_timer_create(struct k_itimer *timer) | 
 | { | 
 | 	/* Insure that a newly created timer is off */ | 
 | 	timer->it.mmtimer.clock = TIMER_OFF; | 
 | 	return 0; | 
 | } | 
 |  | 
 | /* This does not really delete a timer. It just insures | 
 |  * that the timer is not active | 
 |  * | 
 |  * Assumption: it_lock is already held with irq's disabled | 
 |  */ | 
 | static int sgi_timer_del(struct k_itimer *timr) | 
 | { | 
 | 	int i = timr->it.mmtimer.clock; | 
 | 	cnodeid_t nodeid = timr->it.mmtimer.node; | 
 | 	mmtimer_t *t = timers[nodeid] + i; | 
 | 	unsigned long irqflags; | 
 |  | 
 | 	if (i != TIMER_OFF) { | 
 | 		spin_lock_irqsave(&t->lock, irqflags); | 
 | 		mmtimer_disable_int(cnodeid_to_nasid(nodeid),i); | 
 | 		t->timer = NULL; | 
 | 		timr->it.mmtimer.clock = TIMER_OFF; | 
 | 		timr->it.mmtimer.expires = 0; | 
 | 		spin_unlock_irqrestore(&t->lock, irqflags); | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | #define timespec_to_ns(x) ((x).tv_nsec + (x).tv_sec * NSEC_PER_SEC) | 
 | #define ns_to_timespec(ts, nsec) (ts).tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &(ts).tv_nsec) | 
 |  | 
 | /* Assumption: it_lock is already held with irq's disabled */ | 
 | static void sgi_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting) | 
 | { | 
 |  | 
 | 	if (timr->it.mmtimer.clock == TIMER_OFF) { | 
 | 		cur_setting->it_interval.tv_nsec = 0; | 
 | 		cur_setting->it_interval.tv_sec = 0; | 
 | 		cur_setting->it_value.tv_nsec = 0; | 
 | 		cur_setting->it_value.tv_sec =0; | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	ns_to_timespec(cur_setting->it_interval, timr->it.mmtimer.incr * sgi_clock_period); | 
 | 	ns_to_timespec(cur_setting->it_value, (timr->it.mmtimer.expires - rtc_time())* sgi_clock_period); | 
 | 	return; | 
 | } | 
 |  | 
 |  | 
 | static int sgi_timer_set(struct k_itimer *timr, int flags, | 
 | 	struct itimerspec * new_setting, | 
 | 	struct itimerspec * old_setting) | 
 | { | 
 |  | 
 | 	int i; | 
 | 	unsigned long when, period, irqflags; | 
 | 	int err = 0; | 
 | 	cnodeid_t nodeid; | 
 | 	mmtimer_t *base; | 
 |  | 
 | 	if (old_setting) | 
 | 		sgi_timer_get(timr, old_setting); | 
 |  | 
 | 	sgi_timer_del(timr); | 
 | 	when = timespec_to_ns(new_setting->it_value); | 
 | 	period = timespec_to_ns(new_setting->it_interval); | 
 |  | 
 | 	if (when == 0) | 
 | 		/* Clear timer */ | 
 | 		return 0; | 
 |  | 
 | 	if (flags & TIMER_ABSTIME) { | 
 | 		struct timespec n; | 
 | 		unsigned long now; | 
 |  | 
 | 		getnstimeofday(&n); | 
 | 		now = timespec_to_ns(n); | 
 | 		if (when > now) | 
 | 			when -= now; | 
 | 		else | 
 | 			/* Fire the timer immediately */ | 
 | 			when = 0; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * Convert to sgi clock period. Need to keep rtc_time() as near as possible | 
 | 	 * to getnstimeofday() in order to be as faithful as possible to the time | 
 | 	 * specified. | 
 | 	 */ | 
 | 	when = (when + sgi_clock_period - 1) / sgi_clock_period + rtc_time(); | 
 | 	period = (period + sgi_clock_period - 1)  / sgi_clock_period; | 
 |  | 
 | 	/* | 
 | 	 * We are allocating a local SHub comparator. If we would be moved to another | 
 | 	 * cpu then another SHub may be local to us. Prohibit that by switching off | 
 | 	 * preemption. | 
 | 	 */ | 
 | 	preempt_disable(); | 
 |  | 
 | 	nodeid =  cpu_to_node(smp_processor_id()); | 
 | retry: | 
 | 	/* Don't use an allocated timer, or a deleted one that's pending */ | 
 | 	for(i = 0; i< NUM_COMPARATORS; i++) { | 
 | 		base = timers[nodeid] + i; | 
 | 		if (!base->timer && !base->tasklet.state) { | 
 | 			break; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	if (i == NUM_COMPARATORS) { | 
 | 		preempt_enable(); | 
 | 		return -EBUSY; | 
 | 	} | 
 |  | 
 | 	spin_lock_irqsave(&base->lock, irqflags); | 
 |  | 
 | 	if (base->timer || base->tasklet.state != 0) { | 
 | 		spin_unlock_irqrestore(&base->lock, irqflags); | 
 | 		goto retry; | 
 | 	} | 
 | 	base->timer = timr; | 
 | 	base->cpu = smp_processor_id(); | 
 |  | 
 | 	timr->it.mmtimer.clock = i; | 
 | 	timr->it.mmtimer.node = nodeid; | 
 | 	timr->it.mmtimer.incr = period; | 
 | 	timr->it.mmtimer.expires = when; | 
 |  | 
 | 	if (period == 0) { | 
 | 		if (!mmtimer_setup(i, when)) { | 
 | 			mmtimer_disable_int(-1, i); | 
 | 			posix_timer_event(timr, 0); | 
 | 			timr->it.mmtimer.expires = 0; | 
 | 		} | 
 | 	} else { | 
 | 		timr->it.mmtimer.expires -= period; | 
 | 		if (reschedule_periodic_timer(base)) | 
 | 			err = -EINVAL; | 
 | 	} | 
 |  | 
 | 	spin_unlock_irqrestore(&base->lock, irqflags); | 
 |  | 
 | 	preempt_enable(); | 
 |  | 
 | 	return err; | 
 | } | 
 |  | 
 | static struct k_clock sgi_clock = { | 
 | 	.res = 0, | 
 | 	.clock_set = sgi_clock_set, | 
 | 	.clock_get = sgi_clock_get, | 
 | 	.timer_create = sgi_timer_create, | 
 | 	.nsleep = do_posix_clock_nonanosleep, | 
 | 	.timer_set = sgi_timer_set, | 
 | 	.timer_del = sgi_timer_del, | 
 | 	.timer_get = sgi_timer_get | 
 | }; | 
 |  | 
 | /** | 
 |  * mmtimer_init - device initialization routine | 
 |  * | 
 |  * Does initial setup for the mmtimer device. | 
 |  */ | 
 | static int __init mmtimer_init(void) | 
 | { | 
 | 	unsigned i; | 
 | 	cnodeid_t node, maxn = -1; | 
 |  | 
 | 	if (!ia64_platform_is("sn2")) | 
 | 		return 0; | 
 |  | 
 | 	/* | 
 | 	 * Sanity check the cycles/sec variable | 
 | 	 */ | 
 | 	if (sn_rtc_cycles_per_second < 100000) { | 
 | 		printk(KERN_ERR "%s: unable to determine clock frequency\n", | 
 | 		       MMTIMER_NAME); | 
 | 		goto out1; | 
 | 	} | 
 |  | 
 | 	mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second / | 
 | 			       2) / sn_rtc_cycles_per_second; | 
 |  | 
 | 	if (request_irq(SGI_MMTIMER_VECTOR, mmtimer_interrupt, IRQF_PERCPU, MMTIMER_NAME, NULL)) { | 
 | 		printk(KERN_WARNING "%s: unable to allocate interrupt.", | 
 | 			MMTIMER_NAME); | 
 | 		goto out1; | 
 | 	} | 
 |  | 
 | 	if (misc_register(&mmtimer_miscdev)) { | 
 | 		printk(KERN_ERR "%s: failed to register device\n", | 
 | 		       MMTIMER_NAME); | 
 | 		goto out2; | 
 | 	} | 
 |  | 
 | 	/* Get max numbered node, calculate slots needed */ | 
 | 	for_each_online_node(node) { | 
 | 		maxn = node; | 
 | 	} | 
 | 	maxn++; | 
 |  | 
 | 	/* Allocate list of node ptrs to mmtimer_t's */ | 
 | 	timers = kmalloc(sizeof(mmtimer_t *)*maxn, GFP_KERNEL); | 
 | 	if (timers == NULL) { | 
 | 		printk(KERN_ERR "%s: failed to allocate memory for device\n", | 
 | 				MMTIMER_NAME); | 
 | 		goto out3; | 
 | 	} | 
 |  | 
 | 	memset(timers,0,(sizeof(mmtimer_t *)*maxn)); | 
 |  | 
 | 	/* Allocate mmtimer_t's for each online node */ | 
 | 	for_each_online_node(node) { | 
 | 		timers[node] = kmalloc_node(sizeof(mmtimer_t)*NUM_COMPARATORS, GFP_KERNEL, node); | 
 | 		if (timers[node] == NULL) { | 
 | 			printk(KERN_ERR "%s: failed to allocate memory for device\n", | 
 | 				MMTIMER_NAME); | 
 | 			goto out4; | 
 | 		} | 
 | 		for (i=0; i< NUM_COMPARATORS; i++) { | 
 | 			mmtimer_t * base = timers[node] + i; | 
 |  | 
 | 			spin_lock_init(&base->lock); | 
 | 			base->timer = NULL; | 
 | 			base->cpu = 0; | 
 | 			base->i = i; | 
 | 			tasklet_init(&base->tasklet, mmtimer_tasklet, | 
 | 				(unsigned long) (base)); | 
 | 		} | 
 | 	} | 
 |  | 
 | 	sgi_clock_period = sgi_clock.res = NSEC_PER_SEC / sn_rtc_cycles_per_second; | 
 | 	register_posix_clock(CLOCK_SGI_CYCLE, &sgi_clock); | 
 |  | 
 | 	printk(KERN_INFO "%s: v%s, %ld MHz\n", MMTIMER_DESC, MMTIMER_VERSION, | 
 | 	       sn_rtc_cycles_per_second/(unsigned long)1E6); | 
 |  | 
 | 	return 0; | 
 |  | 
 | out4: | 
 | 	for_each_online_node(node) { | 
 | 		kfree(timers[node]); | 
 | 	} | 
 | out3: | 
 | 	misc_deregister(&mmtimer_miscdev); | 
 | out2: | 
 | 	free_irq(SGI_MMTIMER_VECTOR, NULL); | 
 | out1: | 
 | 	return -1; | 
 | } | 
 |  | 
 | module_init(mmtimer_init); | 
 |  |