diff options
author | Christoph Hellwig <hch@lst.de> | 2017-05-26 11:03:10 +0200 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2017-05-26 12:52:19 +0200 |
commit | 07903ada96139ced48f2f893fe57a26a8fbc6043 (patch) | |
tree | fbe10541b66d424b70767012bbc7717f4b8628a7 /drivers/char/mmtimer.c | |
parent | Linux 4.12-rc2 (diff) | |
download | linux-07903ada96139ced48f2f893fe57a26a8fbc6043.tar.xz linux-07903ada96139ced48f2f893fe57a26a8fbc6043.zip |
mmtimer: Remove the SGI SN2 mmtimer driver
This driver supports direct system clock access on the ancient SGI SN2
IA64 systems, and implement the only non-builtin k_clock instance.
Remove it as any remaining IA64 altix user will be running just as old
distros anyway.
Dimitri Sivanich stated: "Since this is SN2 specific, this can be removed."
Note that this does not affect the never uv_mmtimer driver for x86-based
Altix systems.
[ tglx: Added comment to CLOCK_SGI_CYCLE ]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Link: http://lkml.kernel.org/r/20170526090311.3377-2-hch@lst.de
Diffstat (limited to 'drivers/char/mmtimer.c')
-rw-r--r-- | drivers/char/mmtimer.c | 858 |
1 files changed, 0 insertions, 858 deletions
diff --git a/drivers/char/mmtimer.c b/drivers/char/mmtimer.c deleted file mode 100644 index 0e7fcb04f01e..000000000000 --- a/drivers/char/mmtimer.c +++ /dev/null @@ -1,858 +0,0 @@ -/* - * 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/fs.h> -#include <linux/mmtimer.h> -#include <linux/miscdevice.h> -#include <linux/posix-timers.h> -#include <linux/interrupt.h> -#include <linux/time.h> -#include <linux/math64.h> -#include <linux/mutex.h> -#include <linux/slab.h> - -#include <linux/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 */ - -static struct k_clock sgi_clock; - -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 DEFINE_MUTEX(mmtimer_mutex); -static long mmtimer_ioctl(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, - .unlocked_ioctl = mmtimer_ioctl, - .llseek = noop_llseek, -}; - -/* - * We only have comparison registers RTC1-4 currently available per - * node. RTC0 is used by SAL. - */ -/* Check for an RTC interrupt pending */ -static int 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 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 mmtimer_setup_int_0(int cpu, 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(cpu) << - 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 mmtimer_setup_int_1(int cpu, 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(cpu) << - 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 mmtimer_setup_int_2(int cpu, 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(cpu) << - 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 mmtimer_setup(int cpu, int comparator, unsigned long expires, - u64 *set_completion_time) -{ - switch (comparator) { - case 0: - mmtimer_setup_int_0(cpu, expires); - break; - case 1: - mmtimer_setup_int_1(cpu, expires); - break; - case 2: - mmtimer_setup_int_2(cpu, expires); - break; - } - /* We might've missed our expiration time */ - *set_completion_time = rtc_time(); - if (*set_completion_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 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 COMPARATOR 1 /* The comparator to use */ - -#define TIMER_OFF 0xbadcabLL /* Timer is not setup */ -#define TIMER_SET 0 /* Comparator is set for this timer */ - -#define MMTIMER_INTERVAL_RETRY_INCREMENT_DEFAULT 40 - -/* There is one of these for each timer */ -struct mmtimer { - struct rb_node list; - struct k_itimer *timer; - int cpu; -}; - -struct mmtimer_node { - spinlock_t lock ____cacheline_aligned; - struct rb_root timer_head; - struct rb_node *next; - struct tasklet_struct tasklet; -}; -static struct mmtimer_node *timers; - -static unsigned mmtimer_interval_retry_increment = - MMTIMER_INTERVAL_RETRY_INCREMENT_DEFAULT; -module_param(mmtimer_interval_retry_increment, uint, 0644); -MODULE_PARM_DESC(mmtimer_interval_retry_increment, - "RTC ticks to add to expiration on interval retry (default 40)"); - -/* - * Add a new mmtimer struct to the node's mmtimer list. - * This function assumes the struct mmtimer_node is locked. - */ -static void mmtimer_add_list(struct mmtimer *n) -{ - int nodeid = n->timer->it.mmtimer.node; - unsigned long expires = n->timer->it.mmtimer.expires; - struct rb_node **link = &timers[nodeid].timer_head.rb_node; - struct rb_node *parent = NULL; - struct mmtimer *x; - - /* - * Find the right place in the rbtree: - */ - while (*link) { - parent = *link; - x = rb_entry(parent, struct mmtimer, list); - - if (expires < x->timer->it.mmtimer.expires) - link = &(*link)->rb_left; - else - link = &(*link)->rb_right; - } - - /* - * Insert the timer to the rbtree and check whether it - * replaces the first pending timer - */ - rb_link_node(&n->list, parent, link); - rb_insert_color(&n->list, &timers[nodeid].timer_head); - - if (!timers[nodeid].next || expires < rb_entry(timers[nodeid].next, - struct mmtimer, list)->timer->it.mmtimer.expires) - timers[nodeid].next = &n->list; -} - -/* - * Set the comparator for the next timer. - * This function assumes the struct mmtimer_node is locked. - */ -static void mmtimer_set_next_timer(int nodeid) -{ - struct mmtimer_node *n = &timers[nodeid]; - struct mmtimer *x; - struct k_itimer *t; - u64 expires, exp, set_completion_time; - int i; - -restart: - if (n->next == NULL) - return; - - x = rb_entry(n->next, struct mmtimer, list); - t = x->timer; - if (!t->it.mmtimer.incr) { - /* Not an interval timer */ - if (!mmtimer_setup(x->cpu, COMPARATOR, - t->it.mmtimer.expires, - &set_completion_time)) { - /* Late setup, fire now */ - tasklet_schedule(&n->tasklet); - } - return; - } - - /* Interval timer */ - i = 0; - expires = exp = t->it.mmtimer.expires; - while (!mmtimer_setup(x->cpu, COMPARATOR, expires, - &set_completion_time)) { - int to; - - i++; - expires = set_completion_time + - mmtimer_interval_retry_increment + (1 << i); - /* Calculate overruns as we go. */ - to = ((u64)(expires - exp) / t->it.mmtimer.incr); - if (to) { - t->it_overrun += to; - t->it.mmtimer.expires += t->it.mmtimer.incr * to; - exp = t->it.mmtimer.expires; - } - if (i > 20) { - printk(KERN_ALERT "mmtimer: cannot reschedule timer\n"); - t->it.mmtimer.clock = TIMER_OFF; - n->next = rb_next(&x->list); - rb_erase(&x->list, &n->timer_head); - kfree(x); - goto restart; - } - } -} - -/** - * mmtimer_ioctl - ioctl interface for /dev/mmtimer - * @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 long mmtimer_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - int ret = 0; - - mutex_lock(&mmtimer_mutex); - - 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))) - ret = -EFAULT; - break; - - case MMTIMER_GETFREQ: /* frequency in Hz */ - if(copy_to_user((unsigned long __user *)arg, - &sn_rtc_cycles_per_second, - sizeof(unsigned long))) - ret = -EFAULT; - 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))) - ret = -EFAULT; - break; - default: - ret = -ENOTTY; - break; - } - mutex_unlock(&mmtimer_mutex); - 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 = { - .minor = SGI_MMTIMER, - .name = MMTIMER_NAME, - .fops = &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 timespec64 *tp) -{ - u64 nsec; - - nsec = rtc_time() * sgi_clock_period - + sgi_clock_offset.tv_nsec; - *tp = ns_to_timespec64(nsec); - tp->tv_sec += sgi_clock_offset.tv_sec; - return 0; -}; - -static int sgi_clock_set(const clockid_t clockid, const struct timespec64 *tp) -{ - - u64 nsec; - u32 rem; - - nsec = rtc_time() * sgi_clock_period; - - sgi_clock_offset.tv_sec = tp->tv_sec - div_u64_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; -} - -/** - * 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) -{ - unsigned long expires = 0; - int result = IRQ_NONE; - unsigned indx = cpu_to_node(smp_processor_id()); - struct mmtimer *base; - - spin_lock(&timers[indx].lock); - base = rb_entry(timers[indx].next, struct mmtimer, list); - if (base == NULL) { - spin_unlock(&timers[indx].lock); - return result; - } - - 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(COMPARATOR) > 0) || - (expires && (expires <= rtc_time()))) { - mmtimer_clr_int_pending(COMPARATOR); - tasklet_schedule(&timers[indx].tasklet); - result = IRQ_HANDLED; - } - } - spin_unlock(&timers[indx].lock); - return result; -} - -static void mmtimer_tasklet(unsigned long data) -{ - int nodeid = data; - struct mmtimer_node *mn = &timers[nodeid]; - struct mmtimer *x; - struct k_itimer *t; - unsigned long flags; - - /* Send signal and deal with periodic signals */ - spin_lock_irqsave(&mn->lock, flags); - if (!mn->next) - goto out; - - x = rb_entry(mn->next, struct mmtimer, list); - t = x->timer; - - if (t->it.mmtimer.clock == TIMER_OFF) - goto out; - - t->it_overrun = 0; - - mn->next = rb_next(&x->list); - rb_erase(&x->list, &mn->timer_head); - - if (posix_timer_event(t, 0) != 0) - t->it_overrun++; - - if(t->it.mmtimer.incr) { - t->it.mmtimer.expires += t->it.mmtimer.incr; - mmtimer_add_list(x); - } else { - /* Ensure we don't false trigger in mmtimer_interrupt */ - t->it.mmtimer.clock = TIMER_OFF; - t->it.mmtimer.expires = 0; - kfree(x); - } - /* Set comparator for next timer, if there is one */ - mmtimer_set_next_timer(nodeid); - - t->it_overrun_last = t->it_overrun; -out: - spin_unlock_irqrestore(&mn->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) -{ - cnodeid_t nodeid = timr->it.mmtimer.node; - unsigned long irqflags; - - spin_lock_irqsave(&timers[nodeid].lock, irqflags); - if (timr->it.mmtimer.clock != TIMER_OFF) { - unsigned long expires = timr->it.mmtimer.expires; - struct rb_node *n = timers[nodeid].timer_head.rb_node; - struct mmtimer *uninitialized_var(t); - int r = 0; - - timr->it.mmtimer.clock = TIMER_OFF; - timr->it.mmtimer.expires = 0; - - while (n) { - t = rb_entry(n, struct mmtimer, list); - if (t->timer == timr) - break; - - if (expires < t->timer->it.mmtimer.expires) - n = n->rb_left; - else - n = n->rb_right; - } - - if (!n) { - spin_unlock_irqrestore(&timers[nodeid].lock, irqflags); - return 0; - } - - if (timers[nodeid].next == n) { - timers[nodeid].next = rb_next(n); - r = 1; - } - - rb_erase(n, &timers[nodeid].timer_head); - kfree(t); - - if (r) { - mmtimer_disable_int(cnodeid_to_nasid(nodeid), - COMPARATOR); - mmtimer_set_next_timer(nodeid); - } - } - spin_unlock_irqrestore(&timers[nodeid].lock, irqflags); - return 0; -} - -/* Assumption: it_lock is already held with irq's disabled */ -static void sgi_timer_get(struct k_itimer *timr, struct itimerspec64 *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; - } - - cur_setting->it_interval = ns_to_timespec64(timr->it.mmtimer.incr * sgi_clock_period); - cur_setting->it_value = ns_to_timespec64((timr->it.mmtimer.expires - rtc_time()) * sgi_clock_period); -} - - -static int sgi_timer_set(struct k_itimer *timr, int flags, - struct itimerspec64 *new_setting, - struct itimerspec64 *old_setting) -{ - unsigned long when, period, irqflags; - int err = 0; - cnodeid_t nodeid; - struct mmtimer *base; - struct rb_node *n; - - if (old_setting) - sgi_timer_get(timr, old_setting); - - sgi_timer_del(timr); - when = timespec64_to_ns(&new_setting->it_value); - period = timespec64_to_ns(&new_setting->it_interval); - - if (when == 0) - /* Clear timer */ - return 0; - - base = kmalloc(sizeof(struct mmtimer), GFP_KERNEL); - if (base == NULL) - return -ENOMEM; - - if (flags & TIMER_ABSTIME) { - struct timespec64 n; - unsigned long now; - - getnstimeofday64(&n); - now = timespec64_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()); - - /* Lock the node timer structure */ - spin_lock_irqsave(&timers[nodeid].lock, irqflags); - - base->timer = timr; - base->cpu = smp_processor_id(); - - timr->it.mmtimer.clock = TIMER_SET; - timr->it.mmtimer.node = nodeid; - timr->it.mmtimer.incr = period; - timr->it.mmtimer.expires = when; - - n = timers[nodeid].next; - - /* Add the new struct mmtimer to node's timer list */ - mmtimer_add_list(base); - - if (timers[nodeid].next == n) { - /* No need to reprogram comparator for now */ - spin_unlock_irqrestore(&timers[nodeid].lock, irqflags); - preempt_enable(); - return err; - } - - /* We need to reprogram the comparator */ - if (n) - mmtimer_disable_int(cnodeid_to_nasid(nodeid), COMPARATOR); - - mmtimer_set_next_timer(nodeid); - - /* Unlock the node timer structure */ - spin_unlock_irqrestore(&timers[nodeid].lock, irqflags); - - preempt_enable(); - - return err; -} - -static int sgi_clock_getres(const clockid_t which_clock, struct timespec64 *tp) -{ - tp->tv_sec = 0; - tp->tv_nsec = sgi_clock_period; - return 0; -} - -static struct k_clock sgi_clock = { - .clock_set = sgi_clock_set, - .clock_get = sgi_clock_get, - .clock_getres = sgi_clock_getres, - .timer_create = sgi_timer_create, - .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) -{ - 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 = kzalloc(sizeof(struct mmtimer_node)*maxn, GFP_KERNEL); - if (!timers) { - printk(KERN_ERR "%s: failed to allocate memory for device\n", - MMTIMER_NAME); - goto out3; - } - - /* Initialize struct mmtimer's for each online node */ - for_each_online_node(node) { - spin_lock_init(&timers[node].lock); - tasklet_init(&timers[node].tasklet, mmtimer_tasklet, - (unsigned long) node); - } - - sgi_clock_period = NSEC_PER_SEC / sn_rtc_cycles_per_second; - posix_timers_register_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; - -out3: - misc_deregister(&mmtimer_miscdev); -out2: - free_irq(SGI_MMTIMER_VECTOR, NULL); -out1: - return -1; -} - -module_init(mmtimer_init); |