Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 2 | * Timer device implementation for SGI SN platforms. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * |
| 4 | * This file is subject to the terms and conditions of the GNU General Public |
| 5 | * License. See the file "COPYING" in the main directory of this archive |
| 6 | * for more details. |
| 7 | * |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 8 | * Copyright (c) 2001-2006 Silicon Graphics, Inc. All rights reserved. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | * |
| 10 | * This driver exports an API that should be supportable by any HPET or IA-PC |
| 11 | * multimedia timer. The code below is currently specific to the SGI Altix |
| 12 | * SHub RTC, however. |
| 13 | * |
| 14 | * 11/01/01 - jbarnes - initial revision |
| 15 | * 9/10/04 - Christoph Lameter - remove interrupt support for kernel inclusion |
| 16 | * 10/1/04 - Christoph Lameter - provide posix clock CLOCK_SGI_CYCLE |
| 17 | * 10/13/04 - Christoph Lameter, Dimitri Sivanich - provide timer interrupt |
| 18 | * support via the posix timer interface |
| 19 | */ |
| 20 | |
| 21 | #include <linux/types.h> |
| 22 | #include <linux/kernel.h> |
| 23 | #include <linux/ioctl.h> |
| 24 | #include <linux/module.h> |
| 25 | #include <linux/init.h> |
| 26 | #include <linux/errno.h> |
| 27 | #include <linux/mm.h> |
Alexey Dobriyan | 4e950f6 | 2007-07-30 02:36:13 +0400 | [diff] [blame] | 28 | #include <linux/fs.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | #include <linux/mmtimer.h> |
| 30 | #include <linux/miscdevice.h> |
| 31 | #include <linux/posix-timers.h> |
| 32 | #include <linux/interrupt.h> |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 33 | #include <linux/time.h> |
| 34 | #include <linux/math64.h> |
Arnd Bergmann | 613655f | 2010-06-02 14:28:52 +0200 | [diff] [blame] | 35 | #include <linux/mutex.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 36 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | |
| 38 | #include <asm/uaccess.h> |
| 39 | #include <asm/sn/addrs.h> |
| 40 | #include <asm/sn/intr.h> |
| 41 | #include <asm/sn/shub_mmr.h> |
| 42 | #include <asm/sn/nodepda.h> |
| 43 | #include <asm/sn/shubio.h> |
| 44 | |
| 45 | MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>"); |
| 46 | MODULE_DESCRIPTION("SGI Altix RTC Timer"); |
| 47 | MODULE_LICENSE("GPL"); |
| 48 | |
| 49 | /* name of the device, usually in /dev */ |
| 50 | #define MMTIMER_NAME "mmtimer" |
| 51 | #define MMTIMER_DESC "SGI Altix RTC Timer" |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 52 | #define MMTIMER_VERSION "2.1" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | |
| 54 | #define RTC_BITS 55 /* 55 bits for this implementation */ |
| 55 | |
Thomas Gleixner | e5e542e | 2011-02-01 13:51:53 +0000 | [diff] [blame] | 56 | static struct k_clock sgi_clock; |
| 57 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | extern unsigned long sn_rtc_cycles_per_second; |
| 59 | |
| 60 | #define RTC_COUNTER_ADDR ((long *)LOCAL_MMR_ADDR(SH_RTC)) |
| 61 | |
| 62 | #define rtc_time() (*RTC_COUNTER_ADDR) |
| 63 | |
Arnd Bergmann | 613655f | 2010-06-02 14:28:52 +0200 | [diff] [blame] | 64 | static DEFINE_MUTEX(mmtimer_mutex); |
Alan Cox | 4cddb88 | 2008-05-22 21:42:44 +0100 | [diff] [blame] | 65 | static long mmtimer_ioctl(struct file *file, unsigned int cmd, |
| 66 | unsigned long arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma); |
| 68 | |
| 69 | /* |
| 70 | * Period in femtoseconds (10^-15 s) |
| 71 | */ |
| 72 | static unsigned long mmtimer_femtoperiod = 0; |
| 73 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 74 | static const struct file_operations mmtimer_fops = { |
Alan Cox | 4cddb88 | 2008-05-22 21:42:44 +0100 | [diff] [blame] | 75 | .owner = THIS_MODULE, |
| 76 | .mmap = mmtimer_mmap, |
| 77 | .unlocked_ioctl = mmtimer_ioctl, |
Arnd Bergmann | 6038f37 | 2010-08-15 18:52:59 +0200 | [diff] [blame] | 78 | .llseek = noop_llseek, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | }; |
| 80 | |
| 81 | /* |
| 82 | * We only have comparison registers RTC1-4 currently available per |
| 83 | * node. RTC0 is used by SAL. |
| 84 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | /* Check for an RTC interrupt pending */ |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 86 | static int mmtimer_int_pending(int comparator) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 87 | { |
| 88 | if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED)) & |
| 89 | SH_EVENT_OCCURRED_RTC1_INT_MASK << comparator) |
| 90 | return 1; |
| 91 | else |
| 92 | return 0; |
| 93 | } |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 94 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | /* Clear the RTC interrupt pending bit */ |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 96 | static void mmtimer_clr_int_pending(int comparator) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | { |
| 98 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS), |
| 99 | SH_EVENT_OCCURRED_RTC1_INT_MASK << comparator); |
| 100 | } |
| 101 | |
| 102 | /* Setup timer on comparator RTC1 */ |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 103 | static void mmtimer_setup_int_0(int cpu, u64 expires) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | { |
| 105 | u64 val; |
| 106 | |
| 107 | /* Disable interrupt */ |
| 108 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 0UL); |
| 109 | |
| 110 | /* Initialize comparator value */ |
| 111 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), -1L); |
| 112 | |
| 113 | /* Clear pending bit */ |
| 114 | mmtimer_clr_int_pending(0); |
| 115 | |
| 116 | val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC1_INT_CONFIG_IDX_SHFT) | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 117 | ((u64)cpu_physical_id(cpu) << |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | SH_RTC1_INT_CONFIG_PID_SHFT); |
| 119 | |
| 120 | /* Set configuration */ |
| 121 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_CONFIG), val); |
| 122 | |
| 123 | /* Enable RTC interrupts */ |
| 124 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 1UL); |
| 125 | |
| 126 | /* Initialize comparator value */ |
| 127 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), expires); |
| 128 | |
| 129 | |
| 130 | } |
| 131 | |
| 132 | /* Setup timer on comparator RTC2 */ |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 133 | static void mmtimer_setup_int_1(int cpu, u64 expires) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | { |
| 135 | u64 val; |
| 136 | |
| 137 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 0UL); |
| 138 | |
| 139 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), -1L); |
| 140 | |
| 141 | mmtimer_clr_int_pending(1); |
| 142 | |
| 143 | val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC2_INT_CONFIG_IDX_SHFT) | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 144 | ((u64)cpu_physical_id(cpu) << |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | SH_RTC2_INT_CONFIG_PID_SHFT); |
| 146 | |
| 147 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_CONFIG), val); |
| 148 | |
| 149 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 1UL); |
| 150 | |
| 151 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), expires); |
| 152 | } |
| 153 | |
| 154 | /* Setup timer on comparator RTC3 */ |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 155 | static void mmtimer_setup_int_2(int cpu, u64 expires) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | { |
| 157 | u64 val; |
| 158 | |
| 159 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 0UL); |
| 160 | |
| 161 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), -1L); |
| 162 | |
| 163 | mmtimer_clr_int_pending(2); |
| 164 | |
| 165 | val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC3_INT_CONFIG_IDX_SHFT) | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 166 | ((u64)cpu_physical_id(cpu) << |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | SH_RTC3_INT_CONFIG_PID_SHFT); |
| 168 | |
| 169 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_CONFIG), val); |
| 170 | |
| 171 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 1UL); |
| 172 | |
| 173 | HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), expires); |
| 174 | } |
| 175 | |
| 176 | /* |
| 177 | * This function must be called with interrupts disabled and preemption off |
| 178 | * in order to insure that the setup succeeds in a deterministic time frame. |
| 179 | * It will check if the interrupt setup succeeded. |
| 180 | */ |
Dimitri Sivanich | dcade5e | 2010-10-27 15:34:20 -0700 | [diff] [blame] | 181 | static int mmtimer_setup(int cpu, int comparator, unsigned long expires, |
| 182 | u64 *set_completion_time) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | switch (comparator) { |
| 185 | case 0: |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 186 | mmtimer_setup_int_0(cpu, expires); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | break; |
| 188 | case 1: |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 189 | mmtimer_setup_int_1(cpu, expires); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | break; |
| 191 | case 2: |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 192 | mmtimer_setup_int_2(cpu, expires); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | break; |
| 194 | } |
| 195 | /* We might've missed our expiration time */ |
Dimitri Sivanich | dcade5e | 2010-10-27 15:34:20 -0700 | [diff] [blame] | 196 | *set_completion_time = rtc_time(); |
| 197 | if (*set_completion_time <= expires) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | return 1; |
| 199 | |
| 200 | /* |
| 201 | * If an interrupt is already pending then its okay |
| 202 | * if not then we failed |
| 203 | */ |
| 204 | return mmtimer_int_pending(comparator); |
| 205 | } |
| 206 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 207 | static int mmtimer_disable_int(long nasid, int comparator) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | { |
| 209 | switch (comparator) { |
| 210 | case 0: |
| 211 | nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), |
| 212 | 0UL) : REMOTE_HUB_S(nasid, SH_RTC1_INT_ENABLE, 0UL); |
| 213 | break; |
| 214 | case 1: |
| 215 | nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), |
| 216 | 0UL) : REMOTE_HUB_S(nasid, SH_RTC2_INT_ENABLE, 0UL); |
| 217 | break; |
| 218 | case 2: |
| 219 | nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), |
| 220 | 0UL) : REMOTE_HUB_S(nasid, SH_RTC3_INT_ENABLE, 0UL); |
| 221 | break; |
| 222 | default: |
| 223 | return -EFAULT; |
| 224 | } |
| 225 | return 0; |
| 226 | } |
| 227 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 228 | #define COMPARATOR 1 /* The comparator to use */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 230 | #define TIMER_OFF 0xbadcabLL /* Timer is not setup */ |
| 231 | #define TIMER_SET 0 /* Comparator is set for this timer */ |
| 232 | |
Dimitri Sivanich | dcade5e | 2010-10-27 15:34:20 -0700 | [diff] [blame] | 233 | #define MMTIMER_INTERVAL_RETRY_INCREMENT_DEFAULT 40 |
| 234 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 235 | /* There is one of these for each timer */ |
| 236 | struct mmtimer { |
| 237 | struct rb_node list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | struct k_itimer *timer; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | int cpu; |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 240 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 242 | struct mmtimer_node { |
| 243 | spinlock_t lock ____cacheline_aligned; |
| 244 | struct rb_root timer_head; |
| 245 | struct rb_node *next; |
| 246 | struct tasklet_struct tasklet; |
| 247 | }; |
| 248 | static struct mmtimer_node *timers; |
| 249 | |
Dimitri Sivanich | dcade5e | 2010-10-27 15:34:20 -0700 | [diff] [blame] | 250 | static unsigned mmtimer_interval_retry_increment = |
| 251 | MMTIMER_INTERVAL_RETRY_INCREMENT_DEFAULT; |
| 252 | module_param(mmtimer_interval_retry_increment, uint, 0644); |
| 253 | MODULE_PARM_DESC(mmtimer_interval_retry_increment, |
| 254 | "RTC ticks to add to expiration on interval retry (default 40)"); |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 255 | |
| 256 | /* |
| 257 | * Add a new mmtimer struct to the node's mmtimer list. |
| 258 | * This function assumes the struct mmtimer_node is locked. |
| 259 | */ |
| 260 | static void mmtimer_add_list(struct mmtimer *n) |
| 261 | { |
| 262 | int nodeid = n->timer->it.mmtimer.node; |
| 263 | unsigned long expires = n->timer->it.mmtimer.expires; |
| 264 | struct rb_node **link = &timers[nodeid].timer_head.rb_node; |
| 265 | struct rb_node *parent = NULL; |
| 266 | struct mmtimer *x; |
| 267 | |
| 268 | /* |
| 269 | * Find the right place in the rbtree: |
| 270 | */ |
| 271 | while (*link) { |
| 272 | parent = *link; |
| 273 | x = rb_entry(parent, struct mmtimer, list); |
| 274 | |
| 275 | if (expires < x->timer->it.mmtimer.expires) |
| 276 | link = &(*link)->rb_left; |
| 277 | else |
| 278 | link = &(*link)->rb_right; |
| 279 | } |
| 280 | |
| 281 | /* |
| 282 | * Insert the timer to the rbtree and check whether it |
| 283 | * replaces the first pending timer |
| 284 | */ |
| 285 | rb_link_node(&n->list, parent, link); |
| 286 | rb_insert_color(&n->list, &timers[nodeid].timer_head); |
| 287 | |
| 288 | if (!timers[nodeid].next || expires < rb_entry(timers[nodeid].next, |
| 289 | struct mmtimer, list)->timer->it.mmtimer.expires) |
| 290 | timers[nodeid].next = &n->list; |
| 291 | } |
| 292 | |
| 293 | /* |
| 294 | * Set the comparator for the next timer. |
| 295 | * This function assumes the struct mmtimer_node is locked. |
| 296 | */ |
| 297 | static void mmtimer_set_next_timer(int nodeid) |
| 298 | { |
| 299 | struct mmtimer_node *n = &timers[nodeid]; |
| 300 | struct mmtimer *x; |
| 301 | struct k_itimer *t; |
Dimitri Sivanich | dcade5e | 2010-10-27 15:34:20 -0700 | [diff] [blame] | 302 | u64 expires, exp, set_completion_time; |
| 303 | int i; |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 304 | |
| 305 | restart: |
| 306 | if (n->next == NULL) |
| 307 | return; |
| 308 | |
| 309 | x = rb_entry(n->next, struct mmtimer, list); |
| 310 | t = x->timer; |
| 311 | if (!t->it.mmtimer.incr) { |
| 312 | /* Not an interval timer */ |
| 313 | if (!mmtimer_setup(x->cpu, COMPARATOR, |
Dimitri Sivanich | dcade5e | 2010-10-27 15:34:20 -0700 | [diff] [blame] | 314 | t->it.mmtimer.expires, |
| 315 | &set_completion_time)) { |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 316 | /* Late setup, fire now */ |
| 317 | tasklet_schedule(&n->tasklet); |
| 318 | } |
| 319 | return; |
| 320 | } |
| 321 | |
| 322 | /* Interval timer */ |
Dimitri Sivanich | dcade5e | 2010-10-27 15:34:20 -0700 | [diff] [blame] | 323 | i = 0; |
| 324 | expires = exp = t->it.mmtimer.expires; |
| 325 | while (!mmtimer_setup(x->cpu, COMPARATOR, expires, |
| 326 | &set_completion_time)) { |
| 327 | int to; |
| 328 | |
| 329 | i++; |
| 330 | expires = set_completion_time + |
| 331 | mmtimer_interval_retry_increment + (1 << i); |
| 332 | /* Calculate overruns as we go. */ |
| 333 | to = ((u64)(expires - exp) / t->it.mmtimer.incr); |
| 334 | if (to) { |
| 335 | t->it_overrun += to; |
| 336 | t->it.mmtimer.expires += t->it.mmtimer.incr * to; |
| 337 | exp = t->it.mmtimer.expires; |
| 338 | } |
| 339 | if (i > 20) { |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 340 | printk(KERN_ALERT "mmtimer: cannot reschedule timer\n"); |
| 341 | t->it.mmtimer.clock = TIMER_OFF; |
| 342 | n->next = rb_next(&x->list); |
| 343 | rb_erase(&x->list, &n->timer_head); |
| 344 | kfree(x); |
| 345 | goto restart; |
| 346 | } |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 347 | } |
| 348 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 349 | |
| 350 | /** |
| 351 | * mmtimer_ioctl - ioctl interface for /dev/mmtimer |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | * @file: file structure for the device |
| 353 | * @cmd: command to execute |
| 354 | * @arg: optional argument to command |
| 355 | * |
| 356 | * Executes the command specified by @cmd. Returns 0 for success, < 0 for |
| 357 | * failure. |
| 358 | * |
| 359 | * Valid commands: |
| 360 | * |
| 361 | * %MMTIMER_GETOFFSET - Should return the offset (relative to the start |
| 362 | * of the page where the registers are mapped) for the counter in question. |
| 363 | * |
| 364 | * %MMTIMER_GETRES - Returns the resolution of the clock in femto (10^-15) |
| 365 | * seconds |
| 366 | * |
| 367 | * %MMTIMER_GETFREQ - Copies the frequency of the clock in Hz to the address |
| 368 | * specified by @arg |
| 369 | * |
| 370 | * %MMTIMER_GETBITS - Returns the number of bits in the clock's counter |
| 371 | * |
| 372 | * %MMTIMER_MMAPAVAIL - Returns 1 if the registers can be mmap'd into userspace |
| 373 | * |
| 374 | * %MMTIMER_GETCOUNTER - Gets the current value in the counter and places it |
| 375 | * in the address specified by @arg. |
| 376 | */ |
Alan Cox | 4cddb88 | 2008-05-22 21:42:44 +0100 | [diff] [blame] | 377 | static long mmtimer_ioctl(struct file *file, unsigned int cmd, |
| 378 | unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | { |
| 380 | int ret = 0; |
| 381 | |
Arnd Bergmann | 613655f | 2010-06-02 14:28:52 +0200 | [diff] [blame] | 382 | mutex_lock(&mmtimer_mutex); |
Alan Cox | 4cddb88 | 2008-05-22 21:42:44 +0100 | [diff] [blame] | 383 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | switch (cmd) { |
| 385 | case MMTIMER_GETOFFSET: /* offset of the counter */ |
| 386 | /* |
| 387 | * SN RTC registers are on their own 64k page |
| 388 | */ |
| 389 | if(PAGE_SIZE <= (1 << 16)) |
| 390 | ret = (((long)RTC_COUNTER_ADDR) & (PAGE_SIZE-1)) / 8; |
| 391 | else |
| 392 | ret = -ENOSYS; |
| 393 | break; |
| 394 | |
| 395 | case MMTIMER_GETRES: /* resolution of the clock in 10^-15 s */ |
| 396 | if(copy_to_user((unsigned long __user *)arg, |
| 397 | &mmtimer_femtoperiod, sizeof(unsigned long))) |
Alan Cox | 4cddb88 | 2008-05-22 21:42:44 +0100 | [diff] [blame] | 398 | ret = -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 399 | break; |
| 400 | |
| 401 | case MMTIMER_GETFREQ: /* frequency in Hz */ |
| 402 | if(copy_to_user((unsigned long __user *)arg, |
| 403 | &sn_rtc_cycles_per_second, |
| 404 | sizeof(unsigned long))) |
Alan Cox | 4cddb88 | 2008-05-22 21:42:44 +0100 | [diff] [blame] | 405 | ret = -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | break; |
| 407 | |
| 408 | case MMTIMER_GETBITS: /* number of bits in the clock */ |
| 409 | ret = RTC_BITS; |
| 410 | break; |
| 411 | |
| 412 | case MMTIMER_MMAPAVAIL: /* can we mmap the clock into userspace? */ |
| 413 | ret = (PAGE_SIZE <= (1 << 16)) ? 1 : 0; |
| 414 | break; |
| 415 | |
| 416 | case MMTIMER_GETCOUNTER: |
| 417 | if(copy_to_user((unsigned long __user *)arg, |
| 418 | RTC_COUNTER_ADDR, sizeof(unsigned long))) |
Alan Cox | 4cddb88 | 2008-05-22 21:42:44 +0100 | [diff] [blame] | 419 | ret = -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 420 | break; |
| 421 | default: |
Alan Cox | 4cddb88 | 2008-05-22 21:42:44 +0100 | [diff] [blame] | 422 | ret = -ENOTTY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | break; |
| 424 | } |
Arnd Bergmann | 613655f | 2010-06-02 14:28:52 +0200 | [diff] [blame] | 425 | mutex_unlock(&mmtimer_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 426 | return ret; |
| 427 | } |
| 428 | |
| 429 | /** |
| 430 | * mmtimer_mmap - maps the clock's registers into userspace |
| 431 | * @file: file structure for the device |
| 432 | * @vma: VMA to map the registers into |
| 433 | * |
| 434 | * Calls remap_pfn_range() to map the clock's registers into |
| 435 | * the calling process' address space. |
| 436 | */ |
| 437 | static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma) |
| 438 | { |
| 439 | unsigned long mmtimer_addr; |
| 440 | |
| 441 | if (vma->vm_end - vma->vm_start != PAGE_SIZE) |
| 442 | return -EINVAL; |
| 443 | |
| 444 | if (vma->vm_flags & VM_WRITE) |
| 445 | return -EPERM; |
| 446 | |
| 447 | if (PAGE_SIZE > (1 << 16)) |
| 448 | return -ENOSYS; |
| 449 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 450 | vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); |
| 451 | |
| 452 | mmtimer_addr = __pa(RTC_COUNTER_ADDR); |
| 453 | mmtimer_addr &= ~(PAGE_SIZE - 1); |
| 454 | mmtimer_addr &= 0xfffffffffffffffUL; |
| 455 | |
| 456 | if (remap_pfn_range(vma, vma->vm_start, mmtimer_addr >> PAGE_SHIFT, |
| 457 | PAGE_SIZE, vma->vm_page_prot)) { |
| 458 | printk(KERN_ERR "remap_pfn_range failed in mmtimer.c\n"); |
| 459 | return -EAGAIN; |
| 460 | } |
| 461 | |
| 462 | return 0; |
| 463 | } |
| 464 | |
| 465 | static struct miscdevice mmtimer_miscdev = { |
| 466 | SGI_MMTIMER, |
| 467 | MMTIMER_NAME, |
| 468 | &mmtimer_fops |
| 469 | }; |
| 470 | |
| 471 | static struct timespec sgi_clock_offset; |
| 472 | static int sgi_clock_period; |
| 473 | |
| 474 | /* |
| 475 | * Posix Timer Interface |
| 476 | */ |
| 477 | |
| 478 | static struct timespec sgi_clock_offset; |
| 479 | static int sgi_clock_period; |
| 480 | |
| 481 | static int sgi_clock_get(clockid_t clockid, struct timespec *tp) |
| 482 | { |
| 483 | u64 nsec; |
| 484 | |
| 485 | nsec = rtc_time() * sgi_clock_period |
| 486 | + sgi_clock_offset.tv_nsec; |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 487 | *tp = ns_to_timespec(nsec); |
| 488 | tp->tv_sec += sgi_clock_offset.tv_sec; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | return 0; |
| 490 | }; |
| 491 | |
Richard Cochran | 1e6d767 | 2011-02-01 13:50:58 +0000 | [diff] [blame] | 492 | static int sgi_clock_set(const clockid_t clockid, const struct timespec *tp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 493 | { |
| 494 | |
| 495 | u64 nsec; |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 496 | u32 rem; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | |
| 498 | nsec = rtc_time() * sgi_clock_period; |
| 499 | |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 500 | sgi_clock_offset.tv_sec = tp->tv_sec - div_u64_rem(nsec, NSEC_PER_SEC, &rem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | |
| 502 | if (rem <= tp->tv_nsec) |
| 503 | sgi_clock_offset.tv_nsec = tp->tv_sec - rem; |
| 504 | else { |
| 505 | sgi_clock_offset.tv_nsec = tp->tv_sec + NSEC_PER_SEC - rem; |
| 506 | sgi_clock_offset.tv_sec--; |
| 507 | } |
| 508 | return 0; |
| 509 | } |
| 510 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 511 | /** |
| 512 | * mmtimer_interrupt - timer interrupt handler |
| 513 | * @irq: irq received |
| 514 | * @dev_id: device the irq came from |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | * |
| 516 | * Called when one of the comarators matches the counter, This |
| 517 | * routine will send signals to processes that have requested |
| 518 | * them. |
| 519 | * |
| 520 | * This interrupt is run in an interrupt context |
| 521 | * by the SHUB. It is therefore safe to locally access SHub |
| 522 | * registers. |
| 523 | */ |
| 524 | static irqreturn_t |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 525 | mmtimer_interrupt(int irq, void *dev_id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 527 | unsigned long expires = 0; |
| 528 | int result = IRQ_NONE; |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 529 | unsigned indx = cpu_to_node(smp_processor_id()); |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 530 | struct mmtimer *base; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 531 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 532 | spin_lock(&timers[indx].lock); |
| 533 | base = rb_entry(timers[indx].next, struct mmtimer, list); |
| 534 | if (base == NULL) { |
| 535 | spin_unlock(&timers[indx].lock); |
| 536 | return result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | } |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 538 | |
| 539 | if (base->cpu == smp_processor_id()) { |
| 540 | if (base->timer) |
| 541 | expires = base->timer->it.mmtimer.expires; |
| 542 | /* expires test won't work with shared irqs */ |
| 543 | if ((mmtimer_int_pending(COMPARATOR) > 0) || |
| 544 | (expires && (expires <= rtc_time()))) { |
| 545 | mmtimer_clr_int_pending(COMPARATOR); |
| 546 | tasklet_schedule(&timers[indx].tasklet); |
| 547 | result = IRQ_HANDLED; |
| 548 | } |
| 549 | } |
| 550 | spin_unlock(&timers[indx].lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | return result; |
| 552 | } |
| 553 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 554 | static void mmtimer_tasklet(unsigned long data) |
| 555 | { |
| 556 | int nodeid = data; |
| 557 | struct mmtimer_node *mn = &timers[nodeid]; |
Julia Lawall | 0fbcae2 | 2010-03-10 15:23:52 -0800 | [diff] [blame] | 558 | struct mmtimer *x; |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 559 | struct k_itimer *t; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | unsigned long flags; |
| 561 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | /* Send signal and deal with periodic signals */ |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 563 | spin_lock_irqsave(&mn->lock, flags); |
| 564 | if (!mn->next) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 565 | goto out; |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 566 | |
| 567 | x = rb_entry(mn->next, struct mmtimer, list); |
| 568 | t = x->timer; |
| 569 | |
| 570 | if (t->it.mmtimer.clock == TIMER_OFF) |
| 571 | goto out; |
| 572 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | t->it_overrun = 0; |
| 574 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 575 | mn->next = rb_next(&x->list); |
| 576 | rb_erase(&x->list, &mn->timer_head); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 578 | if (posix_timer_event(t, 0) != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 579 | t->it_overrun++; |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 580 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 581 | if(t->it.mmtimer.incr) { |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 582 | t->it.mmtimer.expires += t->it.mmtimer.incr; |
| 583 | mmtimer_add_list(x); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | } else { |
| 585 | /* Ensure we don't false trigger in mmtimer_interrupt */ |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 586 | t->it.mmtimer.clock = TIMER_OFF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | t->it.mmtimer.expires = 0; |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 588 | kfree(x); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | } |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 590 | /* Set comparator for next timer, if there is one */ |
| 591 | mmtimer_set_next_timer(nodeid); |
| 592 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 593 | t->it_overrun_last = t->it_overrun; |
| 594 | out: |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 595 | spin_unlock_irqrestore(&mn->lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 596 | } |
| 597 | |
| 598 | static int sgi_timer_create(struct k_itimer *timer) |
| 599 | { |
| 600 | /* Insure that a newly created timer is off */ |
| 601 | timer->it.mmtimer.clock = TIMER_OFF; |
| 602 | return 0; |
| 603 | } |
| 604 | |
| 605 | /* This does not really delete a timer. It just insures |
| 606 | * that the timer is not active |
| 607 | * |
| 608 | * Assumption: it_lock is already held with irq's disabled |
| 609 | */ |
| 610 | static int sgi_timer_del(struct k_itimer *timr) |
| 611 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | cnodeid_t nodeid = timr->it.mmtimer.node; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 613 | unsigned long irqflags; |
| 614 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 615 | spin_lock_irqsave(&timers[nodeid].lock, irqflags); |
| 616 | if (timr->it.mmtimer.clock != TIMER_OFF) { |
| 617 | unsigned long expires = timr->it.mmtimer.expires; |
| 618 | struct rb_node *n = timers[nodeid].timer_head.rb_node; |
| 619 | struct mmtimer *uninitialized_var(t); |
| 620 | int r = 0; |
| 621 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 622 | timr->it.mmtimer.clock = TIMER_OFF; |
| 623 | timr->it.mmtimer.expires = 0; |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 624 | |
| 625 | while (n) { |
| 626 | t = rb_entry(n, struct mmtimer, list); |
| 627 | if (t->timer == timr) |
| 628 | break; |
| 629 | |
| 630 | if (expires < t->timer->it.mmtimer.expires) |
| 631 | n = n->rb_left; |
| 632 | else |
| 633 | n = n->rb_right; |
| 634 | } |
| 635 | |
| 636 | if (!n) { |
| 637 | spin_unlock_irqrestore(&timers[nodeid].lock, irqflags); |
| 638 | return 0; |
| 639 | } |
| 640 | |
| 641 | if (timers[nodeid].next == n) { |
| 642 | timers[nodeid].next = rb_next(n); |
| 643 | r = 1; |
| 644 | } |
| 645 | |
| 646 | rb_erase(n, &timers[nodeid].timer_head); |
| 647 | kfree(t); |
| 648 | |
| 649 | if (r) { |
| 650 | mmtimer_disable_int(cnodeid_to_nasid(nodeid), |
| 651 | COMPARATOR); |
| 652 | mmtimer_set_next_timer(nodeid); |
| 653 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 654 | } |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 655 | spin_unlock_irqrestore(&timers[nodeid].lock, irqflags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 656 | return 0; |
| 657 | } |
| 658 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 659 | /* Assumption: it_lock is already held with irq's disabled */ |
| 660 | static void sgi_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting) |
| 661 | { |
| 662 | |
| 663 | if (timr->it.mmtimer.clock == TIMER_OFF) { |
| 664 | cur_setting->it_interval.tv_nsec = 0; |
| 665 | cur_setting->it_interval.tv_sec = 0; |
| 666 | cur_setting->it_value.tv_nsec = 0; |
| 667 | cur_setting->it_value.tv_sec =0; |
| 668 | return; |
| 669 | } |
| 670 | |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 671 | cur_setting->it_interval = ns_to_timespec(timr->it.mmtimer.incr * sgi_clock_period); |
| 672 | cur_setting->it_value = ns_to_timespec((timr->it.mmtimer.expires - rtc_time()) * sgi_clock_period); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | } |
| 674 | |
| 675 | |
| 676 | static int sgi_timer_set(struct k_itimer *timr, int flags, |
| 677 | struct itimerspec * new_setting, |
| 678 | struct itimerspec * old_setting) |
| 679 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | unsigned long when, period, irqflags; |
| 681 | int err = 0; |
| 682 | cnodeid_t nodeid; |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 683 | struct mmtimer *base; |
| 684 | struct rb_node *n; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 685 | |
| 686 | if (old_setting) |
| 687 | sgi_timer_get(timr, old_setting); |
| 688 | |
| 689 | sgi_timer_del(timr); |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 690 | when = timespec_to_ns(&new_setting->it_value); |
| 691 | period = timespec_to_ns(&new_setting->it_interval); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | |
| 693 | if (when == 0) |
| 694 | /* Clear timer */ |
| 695 | return 0; |
| 696 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 697 | base = kmalloc(sizeof(struct mmtimer), GFP_KERNEL); |
| 698 | if (base == NULL) |
| 699 | return -ENOMEM; |
| 700 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 701 | if (flags & TIMER_ABSTIME) { |
| 702 | struct timespec n; |
| 703 | unsigned long now; |
| 704 | |
| 705 | getnstimeofday(&n); |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 706 | now = timespec_to_ns(&n); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | if (when > now) |
| 708 | when -= now; |
| 709 | else |
| 710 | /* Fire the timer immediately */ |
| 711 | when = 0; |
| 712 | } |
| 713 | |
| 714 | /* |
| 715 | * Convert to sgi clock period. Need to keep rtc_time() as near as possible |
| 716 | * to getnstimeofday() in order to be as faithful as possible to the time |
| 717 | * specified. |
| 718 | */ |
| 719 | when = (when + sgi_clock_period - 1) / sgi_clock_period + rtc_time(); |
| 720 | period = (period + sgi_clock_period - 1) / sgi_clock_period; |
| 721 | |
| 722 | /* |
| 723 | * We are allocating a local SHub comparator. If we would be moved to another |
| 724 | * cpu then another SHub may be local to us. Prohibit that by switching off |
| 725 | * preemption. |
| 726 | */ |
| 727 | preempt_disable(); |
| 728 | |
Tony Luck | 55642d3 | 2005-09-15 17:00:10 -0700 | [diff] [blame] | 729 | nodeid = cpu_to_node(smp_processor_id()); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 730 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 731 | /* Lock the node timer structure */ |
| 732 | spin_lock_irqsave(&timers[nodeid].lock, irqflags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 733 | |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 734 | base->timer = timr; |
| 735 | base->cpu = smp_processor_id(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 736 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 737 | timr->it.mmtimer.clock = TIMER_SET; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | timr->it.mmtimer.node = nodeid; |
| 739 | timr->it.mmtimer.incr = period; |
| 740 | timr->it.mmtimer.expires = when; |
| 741 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 742 | n = timers[nodeid].next; |
| 743 | |
| 744 | /* Add the new struct mmtimer to node's timer list */ |
| 745 | mmtimer_add_list(base); |
| 746 | |
| 747 | if (timers[nodeid].next == n) { |
| 748 | /* No need to reprogram comparator for now */ |
| 749 | spin_unlock_irqrestore(&timers[nodeid].lock, irqflags); |
| 750 | preempt_enable(); |
| 751 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 752 | } |
| 753 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 754 | /* We need to reprogram the comparator */ |
| 755 | if (n) |
| 756 | mmtimer_disable_int(cnodeid_to_nasid(nodeid), COMPARATOR); |
| 757 | |
| 758 | mmtimer_set_next_timer(nodeid); |
| 759 | |
| 760 | /* Unlock the node timer structure */ |
| 761 | spin_unlock_irqrestore(&timers[nodeid].lock, irqflags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 762 | |
| 763 | preempt_enable(); |
| 764 | |
| 765 | return err; |
| 766 | } |
| 767 | |
Thomas Gleixner | e5e542e | 2011-02-01 13:51:53 +0000 | [diff] [blame] | 768 | static int sgi_clock_getres(const clockid_t which_clock, struct timespec *tp) |
| 769 | { |
| 770 | tp->tv_sec = 0; |
Thomas Gleixner | ebaac75 | 2011-02-01 13:51:56 +0000 | [diff] [blame^] | 771 | tp->tv_nsec = sgi_clock_period; |
Thomas Gleixner | e5e542e | 2011-02-01 13:51:53 +0000 | [diff] [blame] | 772 | return 0; |
| 773 | } |
| 774 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 775 | static struct k_clock sgi_clock = { |
Thomas Gleixner | 2fd1f04 | 2011-02-01 13:51:03 +0000 | [diff] [blame] | 776 | .clock_set = sgi_clock_set, |
| 777 | .clock_get = sgi_clock_get, |
Thomas Gleixner | e5e542e | 2011-02-01 13:51:53 +0000 | [diff] [blame] | 778 | .clock_getres = sgi_clock_getres, |
Thomas Gleixner | 2fd1f04 | 2011-02-01 13:51:03 +0000 | [diff] [blame] | 779 | .timer_create = sgi_timer_create, |
Thomas Gleixner | 2fd1f04 | 2011-02-01 13:51:03 +0000 | [diff] [blame] | 780 | .timer_set = sgi_timer_set, |
| 781 | .timer_del = sgi_timer_del, |
| 782 | .timer_get = sgi_timer_get |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 783 | }; |
| 784 | |
| 785 | /** |
| 786 | * mmtimer_init - device initialization routine |
| 787 | * |
| 788 | * Does initial setup for the mmtimer device. |
| 789 | */ |
| 790 | static int __init mmtimer_init(void) |
| 791 | { |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 792 | cnodeid_t node, maxn = -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 793 | |
| 794 | if (!ia64_platform_is("sn2")) |
Bjorn Helgaas | f032f90 | 2006-03-03 15:34:34 -0700 | [diff] [blame] | 795 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | |
| 797 | /* |
| 798 | * Sanity check the cycles/sec variable |
| 799 | */ |
| 800 | if (sn_rtc_cycles_per_second < 100000) { |
| 801 | printk(KERN_ERR "%s: unable to determine clock frequency\n", |
| 802 | MMTIMER_NAME); |
Neil Horman | 5d469ec | 2006-12-06 20:37:08 -0800 | [diff] [blame] | 803 | goto out1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 804 | } |
| 805 | |
| 806 | mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second / |
| 807 | 2) / sn_rtc_cycles_per_second; |
| 808 | |
Thomas Gleixner | 0f2ed4c | 2006-07-01 19:29:33 -0700 | [diff] [blame] | 809 | if (request_irq(SGI_MMTIMER_VECTOR, mmtimer_interrupt, IRQF_PERCPU, MMTIMER_NAME, NULL)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 810 | printk(KERN_WARNING "%s: unable to allocate interrupt.", |
| 811 | MMTIMER_NAME); |
Neil Horman | 5d469ec | 2006-12-06 20:37:08 -0800 | [diff] [blame] | 812 | goto out1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 813 | } |
| 814 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 815 | if (misc_register(&mmtimer_miscdev)) { |
| 816 | printk(KERN_ERR "%s: failed to register device\n", |
| 817 | MMTIMER_NAME); |
Neil Horman | 5d469ec | 2006-12-06 20:37:08 -0800 | [diff] [blame] | 818 | goto out2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | } |
| 820 | |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 821 | /* Get max numbered node, calculate slots needed */ |
| 822 | for_each_online_node(node) { |
| 823 | maxn = node; |
| 824 | } |
| 825 | maxn++; |
| 826 | |
| 827 | /* Allocate list of node ptrs to mmtimer_t's */ |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 828 | timers = kzalloc(sizeof(struct mmtimer_node)*maxn, GFP_KERNEL); |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 829 | if (timers == NULL) { |
| 830 | printk(KERN_ERR "%s: failed to allocate memory for device\n", |
| 831 | MMTIMER_NAME); |
Neil Horman | 5d469ec | 2006-12-06 20:37:08 -0800 | [diff] [blame] | 832 | goto out3; |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 833 | } |
| 834 | |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 835 | /* Initialize struct mmtimer's for each online node */ |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 836 | for_each_online_node(node) { |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 837 | spin_lock_init(&timers[node].lock); |
| 838 | tasklet_init(&timers[node].tasklet, mmtimer_tasklet, |
| 839 | (unsigned long) node); |
Dimitri Sivanich | 76832c2 | 2006-01-06 11:33:41 -0600 | [diff] [blame] | 840 | } |
| 841 | |
Thomas Gleixner | ebaac75 | 2011-02-01 13:51:56 +0000 | [diff] [blame^] | 842 | sgi_clock_period = NSEC_PER_SEC / sn_rtc_cycles_per_second; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 843 | register_posix_clock(CLOCK_SGI_CYCLE, &sgi_clock); |
| 844 | |
| 845 | printk(KERN_INFO "%s: v%s, %ld MHz\n", MMTIMER_DESC, MMTIMER_VERSION, |
| 846 | sn_rtc_cycles_per_second/(unsigned long)1E6); |
| 847 | |
| 848 | return 0; |
Neil Horman | 5d469ec | 2006-12-06 20:37:08 -0800 | [diff] [blame] | 849 | |
Neil Horman | 5d469ec | 2006-12-06 20:37:08 -0800 | [diff] [blame] | 850 | out3: |
Dimitri Sivanich | cbacdd9 | 2008-04-30 00:53:35 -0700 | [diff] [blame] | 851 | kfree(timers); |
Neil Horman | 5d469ec | 2006-12-06 20:37:08 -0800 | [diff] [blame] | 852 | misc_deregister(&mmtimer_miscdev); |
| 853 | out2: |
| 854 | free_irq(SGI_MMTIMER_VECTOR, NULL); |
| 855 | out1: |
| 856 | return -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 857 | } |
| 858 | |
| 859 | module_init(mmtimer_init); |