*
* 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/devfs_fs_kernel.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>
-
-/* This is ugly and jbarnes has promised me to fix this later */
-#include "../../arch/ia64/sn/include/shubio.h"
+#include <asm/sn/clksupport.h>
MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>");
-MODULE_DESCRIPTION("SGI Altix RTC Timer");
+MODULE_DESCRIPTION("Multimedia timer support");
MODULE_LICENSE("GPL");
/* name of the device, usually in /dev */
#define MMTIMER_NAME "mmtimer"
-#define MMTIMER_DESC "SGI Altix RTC Timer"
-#define MMTIMER_VERSION "2.0"
+#define MMTIMER_DESC "IA-PC Multimedia Timer"
+#define MMTIMER_VERSION "1.0"
#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);
.ioctl = mmtimer_ioctl,
};
-/*
- * Comparators and their associated info. Shub has
- * three comparison registers.
- */
-
-/*
- * 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.
- * mmtimer_setup will return the cycles that we were too late if the
- * initialization failed.
- */
-static int inline mmtimer_setup(int comparator, unsigned long expires)
-{
-
- long diff;
-
- 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 */
- diff = rtc_time() - expires;
- if (diff > 0) {
- if (mmtimer_int_pending(comparator)) {
- /* We'll get an interrupt for this once we're done */
- return 0;
- }
- /* Looks like we missed it */
- return diff;
- }
-
- return 0;
-}
-
-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;
-
-/*
- * Total number of comparators is comparators/node * MAX nodes/running kernel
- */
-static mmtimer_t timers[NUM_COMPARATORS*MAX_COMPACT_NODES];
-
/**
* mmtimer_ioctl - ioctl interface for /dev/mmtimer
* @inode: inode of the device
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)))
+ if(copy_to_user((unsigned long *)arg, &mmtimer_femtoperiod,
+ sizeof(unsigned long)))
return -EFAULT;
break;
case MMTIMER_GETFREQ: /* frequency in Hz */
- if(copy_to_user((unsigned long __user *)arg,
+ if(copy_to_user((unsigned long *)arg,
&sn_rtc_cycles_per_second,
sizeof(unsigned long)))
return -EFAULT;
break;
case MMTIMER_GETCOUNTER:
- if(copy_to_user((unsigned long __user *)arg,
- RTC_COUNTER_ADDR, sizeof(unsigned long)))
+ if(copy_to_user((unsigned long *)arg, RTC_COUNTER_ADDR,
+ sizeof(unsigned long)))
return -EFAULT;
break;
default:
* @file: file structure for the device
* @vma: VMA to map the registers into
*
- * Calls remap_pfn_range() to map the clock's registers into
+ * Calls remap_page_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)
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");
+ if (remap_page_range(vma, vma->vm_start, mmtimer_addr, PAGE_SIZE,
+ vma->vm_page_prot)) {
+ printk(KERN_ERR "remap_page_range failed in mmtimer.c\n");
return -EAGAIN;
}
&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(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(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_timer.magic = x->i;
- t->it_overrun--;
-
- n = 0;
- do {
-
- t->it_timer.expires += t->it_incr << n;
- t->it_overrun += 1 << n;
- n++;
- if (n > 20)
- return 1;
-
- } while (mmtimer_setup(x->i, t->it_timer.expires));
-
- return 0;
-}
-
-/**
- * mmtimer_interrupt - timer interrupt handler
- * @irq: irq received
- * @dev_id: device the irq came from
- * @regs: register state upon receipt of the interrupt
- *
- * 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, struct pt_regs *regs)
-{
- int i;
- mmtimer_t *base = timers + cpuid_to_cnodeid(smp_processor_id()) *
- NUM_COMPARATORS;
- unsigned long expires = 0;
- int result = IRQ_NONE;
-
- /*
- * Do this once for each comparison register
- */
- for (i = 0; i < NUM_COMPARATORS; i++) {
- /* Make sure this doesn't get reused before tasklet_sched */
- spin_lock(&base[i].lock);
- if (base[i].cpu == smp_processor_id()) {
- if (base[i].timer)
- expires = base[i].timer->it_timer.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[i].tasklet);
- result = IRQ_HANDLED;
- }
- }
- spin_unlock(&base[i].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 (tasklist_lock.write_lock || posix_timer_event(t, 0) != 0) {
-
- // printk(KERN_WARNING "mmtimer: cannot deliver signal.\n");
-
- t->it_overrun++;
- }
- if(t->it_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_timer.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_timer.magic = 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_timer.magic;
- cnodeid_t nodeid = timr->it_timer.data;
- mmtimer_t *t = timers + nodeid * NUM_COMPARATORS +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_timer.magic = TIMER_OFF;
- timr->it_timer.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_timer.magic == 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_incr * sgi_clock_period);
- ns_to_timespec(cur_setting->it_value, (timr->it_timer.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;
-
- getnstimeofday(&n);
- when -= timespec_to_ns(n);
- }
-
- /*
- * 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 = cpuid_to_cnodeid(smp_processor_id());
- base = timers + nodeid * NUM_COMPARATORS;
-retry:
- /* Don't use an allocated timer, or a deleted one that's pending */
- for(i = 0; i< NUM_COMPARATORS; i++) {
- if (!base[i].timer && !base[i].tasklet.state) {
- break;
- }
- }
-
- if (i == NUM_COMPARATORS) {
- preempt_enable();
- return -EBUSY;
- }
-
- spin_lock_irqsave(&base[i].lock, irqflags);
-
- if (base[i].timer || base[i].tasklet.state != 0) {
- spin_unlock_irqrestore(&base[i].lock, irqflags);
- goto retry;
- }
- base[i].timer = timr;
- base[i].cpu = smp_processor_id();
-
- timr->it_timer.magic = i;
- timr->it_timer.data = nodeid;
- timr->it_incr = period;
- timr->it_timer.expires = when;
-
- if (period == 0) {
- if (mmtimer_setup(i, when)) {
- mmtimer_disable_int(-1, i);
- posix_timer_event(timr, 0);
- timr->it_timer.expires = 0;
- }
- } else {
- timr->it_timer.expires -= period;
- if (reschedule_periodic_timer(base+i))
- err = -EINVAL;
- }
-
- spin_unlock_irqrestore(&base[i].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
*
*/
static int __init mmtimer_init(void)
{
- unsigned i;
-
if (!ia64_platform_is("sn2"))
return -1;
mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second /
2) / sn_rtc_cycles_per_second;
- for (i=0; i< NUM_COMPARATORS*MAX_COMPACT_NODES; i++) {
- spin_lock_init(&timers[i].lock);
- timers[i].timer = NULL;
- timers[i].cpu = 0;
- timers[i].i = i % NUM_COMPARATORS;
- tasklet_init(&timers[i].tasklet, mmtimer_tasklet, (unsigned long) (timers+i));
- }
-
- if (request_irq(SGI_MMTIMER_VECTOR, mmtimer_interrupt, SA_PERCPU_IRQ, MMTIMER_NAME, NULL)) {
- printk(KERN_WARNING "%s: unable to allocate interrupt.",
- MMTIMER_NAME);
- return -1;
- }
-
strcpy(mmtimer_miscdev.devfs_name, MMTIMER_NAME);
if (misc_register(&mmtimer_miscdev)) {
printk(KERN_ERR "%s: failed to register device\n",
return -1;
}
- 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);
git://git.onelab.eu / linux-2.6.git / blobdiff