Index: linux-2.6.9/include/linux/time.h
===================================================================
--- linux-2.6.9.orig/include/linux/time.h 2004-10-20 19:38:03.000000000 -0700
+++ linux-2.6.9/include/linux/time.h 2004-10-20 20:07:38.000000000 -0700
@@ -160,7 +160,7 @@
/*
* The IDs of various hardware clocks
*/
-
+#define CLOCK_SGI_CYCLE 10
#define CLOCK_SGI_CYCLE 10
#define MAX_CLOCKS 16
Index: linux-2.6.9/drivers/char/mmtimer.c
===================================================================
--- linux-2.6.9.orig/drivers/char/mmtimer.c 2004-10-20 19:38:01.000000000 -0700
+++ linux-2.6.9/drivers/char/mmtimer.c 2004-10-20 20:23:01.000000000 -0700
@@ -13,6 +13,9 @@
*
* 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.
*/
#include <linux/types.h>
@@ -26,20 +29,23 @@
#include <linux/mmtimer.h>
#include <linux/miscdevice.h>
#include <linux/posix-timers.h>
+#include <linux/interrupt.h>
+#include <asm/sn/arch.h>
#include <asm/uaccess.h>
#include <asm/sn/addrs.h>
#include <asm/sn/clksupport.h>
+#include <asm/sn/intr.h>
#include <asm/sn/shub_mmr.h>
MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>");
-MODULE_DESCRIPTION("Multimedia timer support");
+MODULE_DESCRIPTION("SGI Altix RTC Timer");
MODULE_LICENSE("GPL");
/* name of the device, usually in /dev */
#define MMTIMER_NAME "mmtimer"
-#define MMTIMER_DESC "IA-PC Multimedia Timer"
-#define MMTIMER_VERSION "1.0"
+#define MMTIMER_DESC "SGI ALtix RTC Timer"
+#define MMTIMER_VERSION "2.0"
#define RTC_BITS 55 /* 55 bits for this implementation */
@@ -58,6 +64,171 @@
.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 interrupt and clear the pending bit if
+ * one is waiting.
+*/
+static int inline mmtimer_int_pending(int comparator) {
+ int pending = 0;
+
+ switch (comparator) {
+ case 0:
+ if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED)) &
+ SH_EVENT_OCCURRED_RTC1_INT_MASK) {
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS),
+ SH_EVENT_OCCURRED_RTC1_INT_MASK);
+ pending = 1;
+ }
+ break;
+ case 1:
+ if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED)) &
+ SH_EVENT_OCCURRED_RTC2_INT_MASK) {
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS),
+ SH_EVENT_OCCURRED_RTC2_INT_MASK);
+ pending = 1;
+ }
+ break;
+ case 2:
+ if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED)) &
+ SH_EVENT_OCCURRED_RTC3_INT_MASK) {
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS),
+ SH_EVENT_OCCURRED_RTC3_INT_MASK);
+ pending = 1;
+ }
+ break;
+ default:
+ return -EFAULT;
+ }
+ return pending;
+}
+
+static void inline mmtimer_set_comparator(int comparator, unsigned long expires) {
+
+ switch (comparator) {
+ case 0:
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), expires);
+ break;
+ case 1:
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), expires);
+ break;
+ case 2:
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), expires);
+ }
+}
+
+static void inline mmtimer_set_int_0(long expires) {
+ u64 val;
+
+ /* Disable interrupt */
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 0UL);
+
+ 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 interrupt before setting compare value.
+ * Doing this after setting the compare value can result
+ * in an interrupt pending without ever calling the handler
+ * (probably a timing issue).
+ */
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 1UL);
+
+ /* Set compare value */
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), expires);
+}
+
+static void inline mmtimer_set_int_1(long expires) {
+ u64 val;
+
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 0UL);
+
+ 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);
+}
+
+static void inline mmtimer_set_int_2(long expires) {
+ u64 val;
+
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 0UL);
+
+ 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);
+}
+
+static int inline mmtimer_set_int(int comparator, long expires) {
+ switch (comparator) {
+ case 0:
+ mmtimer_set_int_0(expires);
+ break;
+ case 1:
+ mmtimer_set_int_1(expires);
+ break;
+ case 2:
+ mmtimer_set_int_2(expires);
+ break;
+ default:
+ return -EFAULT;
+ }
+ return 0;
+}
+
+static int inline mmtimer_disable_int(int comparator) {
+ switch (comparator) {
+ case 0:
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 0UL);
+ break;
+ case 1:
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 0UL);
+ break;
+ case 2:
+ HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 0UL);
+ break;
+ default:
+ return -EFAULT;
+ }
+ return 0;
+}
+
+#define TIMER_OFF 0xbadcabLL
+
+typedef struct mmtimer {
+ struct k_itimer *timer;
+ spinlock_t lock;
+} 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
@@ -183,6 +354,15 @@
static struct timespec sgi_clock_offset;
static int sgi_clock_period;
+/*****
+ * Posix Timer Interface
+ * The posix timer interface provides full support for the posix timer
+ * interface and allows the scheduling of up to three timers.
+ */
+
+static struct timespec sgi_clock_offset;
+static int sgi_clock_period;
+
static int sgi_clock_get(struct timespec *tp) {
u64 nsec;
@@ -194,12 +374,12 @@
};
static int sgi_clock_set(struct timespec *tp) {
-
+
u64 nsec;
u64 rem;
nsec = readq(RTC_COUNTER_ADDR) * 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)
@@ -211,12 +391,201 @@
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 on cpus services
+ * by the SHUB. It is therefore safe to locally access to 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;
+ int result = IRQ_NONE;
+
+ printk("mmtimer interrupt:\n");
+ /*
+ * Do this once for each comparison register
+ */
+ for (i = 0; i < NUM_COMPARATORS; i++) {
+ if (mmtimer_int_pending(i)>0) {
+ struct k_itimer *t = base[i].timer;
+ unsigned long flags;
+
+ printk("mmtimer: processing int on %d expires=%lu incr=%lu rtc=%lu\n",i,t->it_timer.expires, t->it_incr,readq(RTC_COUNTER_ADDR));
+ spin_lock_irqsave(&t->it_lock, flags);
+
+ if (timer_event(t, 0) == 0) {
+ if(t->it_incr == 0) goto clear_timer;
+ t->it_timer.expires += t->it_incr;
+ mmtimer_set_comparator(i, t->it_timer.expires);
+ } else {
+ printk(KERN_WARNING "mmtimer unable to deliver signal");
+ t->it_overrun++;
+clear_timer:
+ mmtimer_disable_int(i);
+ t->it_timer.magic = TIMER_OFF;
+ base[i].timer = NULL;
+ }
+
+ spin_unlock_irqrestore(&t->it_lock, flags);
+ result = IRQ_HANDLED;
+ }
+ }
+ return result;
+}
+
+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
+ */
+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;
+
+ if (i != TIMER_OFF) {
+ spin_lock(&t->lock);
+ mmtimer_disable_int(i);
+ t->timer = NULL;
+ timr->it_timer.magic = TIMER_OFF;
+ spin_unlock(&t->lock);
+ printk("mmtimer: interrupt %d node %d disabled.\n",i, nodeid);
+ }
+ 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)
+
+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);
+ /* readq is atomic so no locking needed */
+ ns_to_timespec(cur_setting->it_value, (timr->it_timer.expires - readq(RTC_COUNTER_ADDR))* 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, irqflags;
+ int err = 0;
+ cnodeid_t nodeid = cpuid_to_cnodeid(smp_processor_id());
+ mmtimer_t *base = timers + nodeid * NUM_COMPARATORS;
+
+ if (old_setting)
+ sgi_timer_get(timr, old_setting);
+
+ sgi_timer_del(timr);
+ when = timespec_to_ns(new_setting->it_value);
+
+ if (when == 0)
+ /* Clear timer */
+ return 0;
+
+ if (flags & TIMER_ABSTIME) {
+ struct timespec n;
+
+ getnstimeofday(&n);
+ when -= timespec_to_ns(n);
+ }
+
+ /* If the time is less than 100ns, fire now and do not set up */
+ if (when < 100) {
+ timer_event(timr, 0);
+ return 0;
+ }
+
+ /* 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();
+retry:
+ for(i = 0; i< NUM_COMPARATORS; i++) {
+ if (!base[i].timer) {
+ break;
+ }
+ }
+
+ if (i == NUM_COMPARATORS) {
+ preempt_enable();
+ return -EBUSY;
+ }
+
+ /* Avoid someone else using this timer by locking .. */
+ spin_lock_irqsave(&base[i].lock, irqflags);
+
+ if (base[i].timer) {
+ spin_unlock_irqrestore(&base[i].lock, irqflags);
+ goto retry;
+ }
+
+ /* Check once more in case we got held off by another IRQ */
+ if (when < 100) {
+ spin_unlock_irqrestore(&base[i].lock, irqflags);
+ preempt_enable();
+ timer_event(timr, 0);
+ return 0;
+ }
+
+ timr->it_timer.magic = i;
+ timr->it_timer.data = nodeid;
+ timr->it_incr = timespec_to_ns(new_setting->it_interval) / sgi_clock_period;
+
+ if (timr->it_incr && timr->it_incr < 3) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ timr->it_timer.expires = when / sgi_clock_period + readq(RTC_COUNTER_ADDR);
+ base[i].timer = timr;
+ if (mmtimer_set_int(i, timr->it_timer.expires)) {
+ err = -EINVAL;
+ }
+out:
+ spin_unlock_irqrestore(&base[i].lock, irqflags);
+ preempt_enable();
+ printk("mmtimer enabled %d. Comparator=%ld. RTC=%ld\n",i, timr->it_timer.expires,readq(RTC_COUNTER_ADDR));
+
+ return err;
+}
+
static struct k_clock sgi_clock = {
.res = 0,
.clock_set = sgi_clock_set,
.clock_get = sgi_clock_get,
- .timer_create = do_posix_clock_notimer_create,
- .nsleep = do_posix_clock_nonanosleep
+ .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
};
/**
@@ -226,6 +595,8 @@
*/
static int __init mmtimer_init(void)
{
+ unsigned i;
+
if (!ia64_platform_is("sn2"))
return -1;
@@ -241,6 +612,17 @@
mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second /
2) / sn_rtc_cycles_per_second;
+ 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;
+ }
+
+ for (i=0; i< NUM_COMPARATORS*MAX_COMPACT_NODES; i++) {
+ spin_lock_init(&timers[i].lock);
+ timers[i].timer = NULL;
+ }
+
strcpy(mmtimer_miscdev.devfs_name, MMTIMER_NAME);
if (misc_register(&mmtimer_miscdev)) {
printk(KERN_ERR "%s: failed to register device\n",
@@ -251,6 +633,9 @@
sgi_clock_period = sgi_clock.res = NSEC_PER_SEC / sn_rtc_cycles_per_second;
register_posix_clock(CLOCK_SGI_CYCLE, &sgi_clock);
+ 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);
Index: linux-2.6.9/include/asm/sn/intr.h
===================================================================
--- linux-2.6.9.orig/include/asm/sn/intr.h 2004-10-20 19:38:03.000000000 -0700
+++ linux-2.6.9/include/asm/sn/intr.h 2004-10-20 20:21:32.000000000 -0700
@@ -11,6 +11,7 @@
#define SGI_UART_VECTOR (0xe9)
#define SGI_PCIBR_ERROR (0x33)
+#define SGI_MMTIMER_VECTOR (0xed)
// These two IRQ's are used by partitioning.
#define SGI_XPC_ACTIVATE (0x30)