include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit...
[linux-3.10.git] / arch / mips / sibyte / common / sb_tbprof.c
1 /*
2  * This program is free software; you can redistribute it and/or
3  * modify it under the terms of the GNU General Public License
4  * as published by the Free Software Foundation; either version 2
5  * of the License, or (at your option) any later version.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  *
12  * You should have received a copy of the GNU General Public License
13  * along with this program; if not, write to the Free Software
14  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
15  *
16  * Copyright (C) 2001, 2002, 2003 Broadcom Corporation
17  * Copyright (C) 2007 Ralf Baechle <ralf@linux-mips.org>
18  * Copyright (C) 2007 MIPS Technologies, Inc.
19  *    written by Ralf Baechle <ralf@linux-mips.org>
20  */
21
22 #undef DEBUG
23
24 #include <linux/device.h>
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/types.h>
28 #include <linux/init.h>
29 #include <linux/interrupt.h>
30 #include <linux/vmalloc.h>
31 #include <linux/fs.h>
32 #include <linux/errno.h>
33 #include <linux/wait.h>
34 #include <asm/io.h>
35 #include <asm/sibyte/sb1250.h>
36
37 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
38 #include <asm/sibyte/bcm1480_regs.h>
39 #include <asm/sibyte/bcm1480_scd.h>
40 #include <asm/sibyte/bcm1480_int.h>
41 #elif defined(CONFIG_SIBYTE_SB1250) || defined(CONFIG_SIBYTE_BCM112X)
42 #include <asm/sibyte/sb1250_regs.h>
43 #include <asm/sibyte/sb1250_scd.h>
44 #include <asm/sibyte/sb1250_int.h>
45 #else
46 #error invalid SiByte UART configuation
47 #endif
48
49 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
50 #undef K_INT_TRACE_FREEZE
51 #define K_INT_TRACE_FREEZE K_BCM1480_INT_TRACE_FREEZE
52 #undef K_INT_PERF_CNT
53 #define K_INT_PERF_CNT K_BCM1480_INT_PERF_CNT
54 #endif
55
56 #include <asm/system.h>
57 #include <asm/uaccess.h>
58
59 #define SBPROF_TB_MAJOR 240
60
61 typedef u64 tb_sample_t[6*256];
62
63 enum open_status {
64         SB_CLOSED,
65         SB_OPENING,
66         SB_OPEN
67 };
68
69 struct sbprof_tb {
70         wait_queue_head_t       tb_sync;
71         wait_queue_head_t       tb_read;
72         struct mutex            lock;
73         enum open_status        open;
74         tb_sample_t             *sbprof_tbbuf;
75         int                     next_tb_sample;
76
77         volatile int            tb_enable;
78         volatile int            tb_armed;
79
80 };
81
82 static struct sbprof_tb sbp;
83
84 #define MAX_SAMPLE_BYTES (24*1024*1024)
85 #define MAX_TBSAMPLE_BYTES (12*1024*1024)
86
87 #define MAX_SAMPLES (MAX_SAMPLE_BYTES/sizeof(u_int32_t))
88 #define TB_SAMPLE_SIZE (sizeof(tb_sample_t))
89 #define MAX_TB_SAMPLES (MAX_TBSAMPLE_BYTES/TB_SAMPLE_SIZE)
90
91 /* ioctls */
92 #define SBPROF_ZBSTART          _IOW('s', 0, int)
93 #define SBPROF_ZBSTOP           _IOW('s', 1, int)
94 #define SBPROF_ZBWAITFULL       _IOW('s', 2, int)
95
96 /*
97  * Routines for using 40-bit SCD cycle counter
98  *
99  * Client responsible for either handling interrupts or making sure
100  * the cycles counter never saturates, e.g., by doing
101  * zclk_timer_init(0) at least every 2^40 - 1 ZCLKs.
102  */
103
104 /*
105  * Configures SCD counter 0 to count ZCLKs starting from val;
106  * Configures SCD counters1,2,3 to count nothing.
107  * Must not be called while gathering ZBbus profiles.
108  */
109
110 #define zclk_timer_init(val) \
111   __asm__ __volatile__ (".set push;" \
112                         ".set mips64;" \
113                         "la   $8, 0xb00204c0;" /* SCD perf_cnt_cfg */ \
114                         "sd   %0, 0x10($8);"   /* write val to counter0 */ \
115                         "sd   %1, 0($8);"      /* config counter0 for zclks*/ \
116                         ".set pop" \
117                         : /* no outputs */ \
118                                                      /* enable, counter0 */ \
119                         : /* inputs */ "r"(val), "r" ((1ULL << 33) | 1ULL) \
120                         : /* modifies */ "$8" )
121
122
123 /* Reads SCD counter 0 and puts result in value
124    unsigned long long val; */
125 #define zclk_get(val) \
126   __asm__ __volatile__ (".set push;" \
127                         ".set mips64;" \
128                         "la   $8, 0xb00204c0;" /* SCD perf_cnt_cfg */ \
129                         "ld   %0, 0x10($8);"   /* write val to counter0 */ \
130                         ".set pop" \
131                         : /* outputs */ "=r"(val) \
132                         : /* inputs */ \
133                         : /* modifies */ "$8" )
134
135 #define DEVNAME "sb_tbprof"
136
137 #define TB_FULL (sbp.next_tb_sample == MAX_TB_SAMPLES)
138
139 /*
140  * Support for ZBbus sampling using the trace buffer
141  *
142  * We use the SCD performance counter interrupt, caused by a Zclk counter
143  * overflow, to trigger the start of tracing.
144  *
145  * We set the trace buffer to sample everything and freeze on
146  * overflow.
147  *
148  * We map the interrupt for trace_buffer_freeze to handle it on CPU 0.
149  *
150  */
151
152 static u64 tb_period;
153
154 static void arm_tb(void)
155 {
156         u64 scdperfcnt;
157         u64 next = (1ULL << 40) - tb_period;
158         u64 tb_options = M_SCD_TRACE_CFG_FREEZE_FULL;
159
160         /*
161          * Generate an SCD_PERFCNT interrupt in TB_PERIOD Zclks to
162          * trigger start of trace.  XXX vary sampling period
163          */
164         __raw_writeq(0, IOADDR(A_SCD_PERF_CNT_1));
165         scdperfcnt = __raw_readq(IOADDR(A_SCD_PERF_CNT_CFG));
166
167         /*
168          * Unfortunately, in Pass 2 we must clear all counters to knock down
169          * a previous interrupt request.  This means that bus profiling
170          * requires ALL of the SCD perf counters.
171          */
172 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
173         __raw_writeq((scdperfcnt & ~M_SPC_CFG_SRC1) |
174                                                 /* keep counters 0,2,3,4,5,6,7 as is */
175                      V_SPC_CFG_SRC1(1),         /* counter 1 counts cycles */
176                      IOADDR(A_BCM1480_SCD_PERF_CNT_CFG0));
177         __raw_writeq(
178                      M_SPC_CFG_ENABLE |         /* enable counting */
179                      M_SPC_CFG_CLEAR |          /* clear all counters */
180                      V_SPC_CFG_SRC1(1),         /* counter 1 counts cycles */
181                      IOADDR(A_BCM1480_SCD_PERF_CNT_CFG1));
182 #else
183         __raw_writeq((scdperfcnt & ~M_SPC_CFG_SRC1) |
184                                                 /* keep counters 0,2,3 as is */
185                      M_SPC_CFG_ENABLE |         /* enable counting */
186                      M_SPC_CFG_CLEAR |          /* clear all counters */
187                      V_SPC_CFG_SRC1(1),         /* counter 1 counts cycles */
188                      IOADDR(A_SCD_PERF_CNT_CFG));
189 #endif
190         __raw_writeq(next, IOADDR(A_SCD_PERF_CNT_1));
191         /* Reset the trace buffer */
192         __raw_writeq(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
193 #if 0 && defined(M_SCD_TRACE_CFG_FORCECNT)
194         /* XXXKW may want to expose control to the data-collector */
195         tb_options |= M_SCD_TRACE_CFG_FORCECNT;
196 #endif
197         __raw_writeq(tb_options, IOADDR(A_SCD_TRACE_CFG));
198         sbp.tb_armed = 1;
199 }
200
201 static irqreturn_t sbprof_tb_intr(int irq, void *dev_id)
202 {
203         int i;
204
205         pr_debug(DEVNAME ": tb_intr\n");
206
207         if (sbp.next_tb_sample < MAX_TB_SAMPLES) {
208                 /* XXX should use XKPHYS to make writes bypass L2 */
209                 u64 *p = sbp.sbprof_tbbuf[sbp.next_tb_sample++];
210                 /* Read out trace */
211                 __raw_writeq(M_SCD_TRACE_CFG_START_READ,
212                              IOADDR(A_SCD_TRACE_CFG));
213                 __asm__ __volatile__ ("sync" : : : "memory");
214                 /* Loop runs backwards because bundles are read out in reverse order */
215                 for (i = 256 * 6; i > 0; i -= 6) {
216                         /* Subscripts decrease to put bundle in the order */
217                         /*   t0 lo, t0 hi, t1 lo, t1 hi, t2 lo, t2 hi */
218                         p[i - 1] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
219                         /* read t2 hi */
220                         p[i - 2] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
221                         /* read t2 lo */
222                         p[i - 3] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
223                         /* read t1 hi */
224                         p[i - 4] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
225                         /* read t1 lo */
226                         p[i - 5] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
227                         /* read t0 hi */
228                         p[i - 6] = __raw_readq(IOADDR(A_SCD_TRACE_READ));
229                         /* read t0 lo */
230                 }
231                 if (!sbp.tb_enable) {
232                         pr_debug(DEVNAME ": tb_intr shutdown\n");
233                         __raw_writeq(M_SCD_TRACE_CFG_RESET,
234                                      IOADDR(A_SCD_TRACE_CFG));
235                         sbp.tb_armed = 0;
236                         wake_up_interruptible(&sbp.tb_sync);
237                 } else {
238                         /* knock down current interrupt and get another one later */
239                         arm_tb();
240                 }
241         } else {
242                 /* No more trace buffer samples */
243                 pr_debug(DEVNAME ": tb_intr full\n");
244                 __raw_writeq(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
245                 sbp.tb_armed = 0;
246                 if (!sbp.tb_enable)
247                         wake_up_interruptible(&sbp.tb_sync);
248                 wake_up_interruptible(&sbp.tb_read);
249         }
250         return IRQ_HANDLED;
251 }
252
253 static irqreturn_t sbprof_pc_intr(int irq, void *dev_id)
254 {
255         printk(DEVNAME ": unexpected pc_intr");
256         return IRQ_NONE;
257 }
258
259 /*
260  * Requires: Already called zclk_timer_init with a value that won't
261  *           saturate 40 bits.  No subsequent use of SCD performance counters
262  *           or trace buffer.
263  */
264
265 static int sbprof_zbprof_start(struct file *filp)
266 {
267         u64 scdperfcnt;
268         int err;
269
270         if (xchg(&sbp.tb_enable, 1))
271                 return -EBUSY;
272
273         pr_debug(DEVNAME ": starting\n");
274
275         sbp.next_tb_sample = 0;
276         filp->f_pos = 0;
277
278         err = request_irq(K_INT_TRACE_FREEZE, sbprof_tb_intr, 0,
279                           DEVNAME " trace freeze", &sbp);
280         if (err)
281                 return -EBUSY;
282
283         /* Make sure there isn't a perf-cnt interrupt waiting */
284         scdperfcnt = __raw_readq(IOADDR(A_SCD_PERF_CNT_CFG));
285         /* Disable and clear counters, override SRC_1 */
286         __raw_writeq((scdperfcnt & ~(M_SPC_CFG_SRC1 | M_SPC_CFG_ENABLE)) |
287                      M_SPC_CFG_ENABLE | M_SPC_CFG_CLEAR | V_SPC_CFG_SRC1(1),
288                      IOADDR(A_SCD_PERF_CNT_CFG));
289
290         /*
291          * We grab this interrupt to prevent others from trying to use
292          * it, even though we don't want to service the interrupts
293          * (they only feed into the trace-on-interrupt mechanism)
294          */
295         if (request_irq(K_INT_PERF_CNT, sbprof_pc_intr, 0, DEVNAME " scd perfcnt", &sbp)) {
296                 free_irq(K_INT_TRACE_FREEZE, &sbp);
297                 return -EBUSY;
298         }
299
300         /*
301          * I need the core to mask these, but the interrupt mapper to
302          *  pass them through.  I am exploiting my knowledge that
303          *  cp0_status masks out IP[5]. krw
304          */
305 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
306         __raw_writeq(K_BCM1480_INT_MAP_I3,
307                      IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_INTERRUPT_MAP_BASE_L) +
308                             ((K_BCM1480_INT_PERF_CNT & 0x3f) << 3)));
309 #else
310         __raw_writeq(K_INT_MAP_I3,
311                      IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MAP_BASE) +
312                             (K_INT_PERF_CNT << 3)));
313 #endif
314
315         /* Initialize address traps */
316         __raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_0));
317         __raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_1));
318         __raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_2));
319         __raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_3));
320
321         __raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_0));
322         __raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_1));
323         __raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_2));
324         __raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_3));
325
326         __raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_0));
327         __raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_1));
328         __raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_2));
329         __raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_3));
330
331         /* Initialize Trace Event 0-7 */
332         /*                              when interrupt  */
333         __raw_writeq(M_SCD_TREVT_INTERRUPT, IOADDR(A_SCD_TRACE_EVENT_0));
334         __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_1));
335         __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_2));
336         __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_3));
337         __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_4));
338         __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_5));
339         __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_6));
340         __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_7));
341
342         /* Initialize Trace Sequence 0-7 */
343         /*                                   Start on event 0 (interrupt) */
344         __raw_writeq(V_SCD_TRSEQ_FUNC_START | 0x0fff,
345                      IOADDR(A_SCD_TRACE_SEQUENCE_0));
346         /*                        dsamp when d used | asamp when a used */
347         __raw_writeq(M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE |
348                      K_SCD_TRSEQ_TRIGGER_ALL,
349                      IOADDR(A_SCD_TRACE_SEQUENCE_1));
350         __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_2));
351         __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_3));
352         __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_4));
353         __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_5));
354         __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_6));
355         __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_7));
356
357         /* Now indicate the PERF_CNT interrupt as a trace-relevant interrupt */
358 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
359         __raw_writeq(1ULL << (K_BCM1480_INT_PERF_CNT & 0x3f),
360                      IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_INTERRUPT_TRACE_L)));
361 #else
362         __raw_writeq(1ULL << K_INT_PERF_CNT,
363                      IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_TRACE)));
364 #endif
365         arm_tb();
366
367         pr_debug(DEVNAME ": done starting\n");
368
369         return 0;
370 }
371
372 static int sbprof_zbprof_stop(void)
373 {
374         int err = 0;
375
376         pr_debug(DEVNAME ": stopping\n");
377
378         if (sbp.tb_enable) {
379                 /*
380                  * XXXKW there is a window here where the intr handler may run,
381                  * see the disable, and do the wake_up before this sleep
382                  * happens.
383                  */
384                 pr_debug(DEVNAME ": wait for disarm\n");
385                 err = wait_event_interruptible(sbp.tb_sync, !sbp.tb_armed);
386                 pr_debug(DEVNAME ": disarm complete, stat %d\n", err);
387
388                 if (err)
389                         return err;
390
391                 sbp.tb_enable = 0;
392                 free_irq(K_INT_TRACE_FREEZE, &sbp);
393                 free_irq(K_INT_PERF_CNT, &sbp);
394         }
395
396         pr_debug(DEVNAME ": done stopping\n");
397
398         return err;
399 }
400
401 static int sbprof_tb_open(struct inode *inode, struct file *filp)
402 {
403         int minor;
404
405         minor = iminor(inode);
406         if (minor != 0)
407                 return -ENODEV;
408
409         if (xchg(&sbp.open, SB_OPENING) != SB_CLOSED)
410                 return -EBUSY;
411
412         memset(&sbp, 0, sizeof(struct sbprof_tb));
413         sbp.sbprof_tbbuf = vmalloc(MAX_TBSAMPLE_BYTES);
414         if (!sbp.sbprof_tbbuf) {
415                 sbp.open = SB_CLOSED;
416                 wmb();
417                 return -ENOMEM;
418         }
419
420         memset(sbp.sbprof_tbbuf, 0, MAX_TBSAMPLE_BYTES);
421         init_waitqueue_head(&sbp.tb_sync);
422         init_waitqueue_head(&sbp.tb_read);
423         mutex_init(&sbp.lock);
424
425         sbp.open = SB_OPEN;
426         wmb();
427
428         return 0;
429 }
430
431 static int sbprof_tb_release(struct inode *inode, struct file *filp)
432 {
433         int minor;
434
435         minor = iminor(inode);
436         if (minor != 0 || sbp.open != SB_CLOSED)
437                 return -ENODEV;
438
439         mutex_lock(&sbp.lock);
440
441         if (sbp.tb_armed || sbp.tb_enable)
442                 sbprof_zbprof_stop();
443
444         vfree(sbp.sbprof_tbbuf);
445         sbp.open = SB_CLOSED;
446         wmb();
447
448         mutex_unlock(&sbp.lock);
449
450         return 0;
451 }
452
453 static ssize_t sbprof_tb_read(struct file *filp, char *buf,
454                               size_t size, loff_t *offp)
455 {
456         int cur_sample, sample_off, cur_count, sample_left;
457         char *src;
458         int   count   =  0;
459         char *dest    =  buf;
460         long  cur_off = *offp;
461
462         if (!access_ok(VERIFY_WRITE, buf, size))
463                 return -EFAULT;
464
465         mutex_lock(&sbp.lock);
466
467         count = 0;
468         cur_sample = cur_off / TB_SAMPLE_SIZE;
469         sample_off = cur_off % TB_SAMPLE_SIZE;
470         sample_left = TB_SAMPLE_SIZE - sample_off;
471
472         while (size && (cur_sample < sbp.next_tb_sample)) {
473                 int err;
474
475                 cur_count = size < sample_left ? size : sample_left;
476                 src = (char *)(((long)sbp.sbprof_tbbuf[cur_sample])+sample_off);
477                 err = __copy_to_user(dest, src, cur_count);
478                 if (err) {
479                         *offp = cur_off + cur_count - err;
480                         mutex_unlock(&sbp.lock);
481                         return err;
482                 }
483                 pr_debug(DEVNAME ": read from sample %d, %d bytes\n",
484                          cur_sample, cur_count);
485                 size -= cur_count;
486                 sample_left -= cur_count;
487                 if (!sample_left) {
488                         cur_sample++;
489                         sample_off = 0;
490                         sample_left = TB_SAMPLE_SIZE;
491                 } else {
492                         sample_off += cur_count;
493                 }
494                 cur_off += cur_count;
495                 dest += cur_count;
496                 count += cur_count;
497         }
498         *offp = cur_off;
499         mutex_unlock(&sbp.lock);
500
501         return count;
502 }
503
504 static long sbprof_tb_ioctl(struct file *filp,
505                             unsigned int command,
506                             unsigned long arg)
507 {
508         int err = 0;
509
510         switch (command) {
511         case SBPROF_ZBSTART:
512                 mutex_lock(&sbp.lock);
513                 err = sbprof_zbprof_start(filp);
514                 mutex_unlock(&sbp.lock);
515                 break;
516
517         case SBPROF_ZBSTOP:
518                 mutex_lock(&sbp.lock);
519                 err = sbprof_zbprof_stop();
520                 mutex_unlock(&sbp.lock);
521                 break;
522
523         case SBPROF_ZBWAITFULL: {
524                 err = wait_event_interruptible(sbp.tb_read, TB_FULL);
525                 if (err)
526                         break;
527
528                 err = put_user(TB_FULL, (int *) arg);
529                 break;
530         }
531
532         default:
533                 err = -EINVAL;
534                 break;
535         }
536
537         return err;
538 }
539
540 static const struct file_operations sbprof_tb_fops = {
541         .owner          = THIS_MODULE,
542         .open           = sbprof_tb_open,
543         .release        = sbprof_tb_release,
544         .read           = sbprof_tb_read,
545         .unlocked_ioctl = sbprof_tb_ioctl,
546         .compat_ioctl   = sbprof_tb_ioctl,
547         .mmap           = NULL,
548 };
549
550 static struct class *tb_class;
551 static struct device *tb_dev;
552
553 static int __init sbprof_tb_init(void)
554 {
555         struct device *dev;
556         struct class *tbc;
557         int err;
558
559         if (register_chrdev(SBPROF_TB_MAJOR, DEVNAME, &sbprof_tb_fops)) {
560                 printk(KERN_WARNING DEVNAME ": initialization failed (dev %d)\n",
561                        SBPROF_TB_MAJOR);
562                 return -EIO;
563         }
564
565         tbc = class_create(THIS_MODULE, "sb_tracebuffer");
566         if (IS_ERR(tbc)) {
567                 err = PTR_ERR(tbc);
568                 goto out_chrdev;
569         }
570
571         tb_class = tbc;
572
573         dev = device_create(tbc, NULL, MKDEV(SBPROF_TB_MAJOR, 0), NULL, "tb");
574         if (IS_ERR(dev)) {
575                 err = PTR_ERR(dev);
576                 goto out_class;
577         }
578         tb_dev = dev;
579
580         sbp.open = SB_CLOSED;
581         wmb();
582         tb_period = zbbus_mhz * 10000LL;
583         pr_info(DEVNAME ": initialized - tb_period = %lld\n",
584                 (long long) tb_period);
585         return 0;
586
587 out_class:
588         class_destroy(tb_class);
589 out_chrdev:
590         unregister_chrdev(SBPROF_TB_MAJOR, DEVNAME);
591
592         return err;
593 }
594
595 static void __exit sbprof_tb_cleanup(void)
596 {
597         device_destroy(tb_class, MKDEV(SBPROF_TB_MAJOR, 0));
598         unregister_chrdev(SBPROF_TB_MAJOR, DEVNAME);
599         class_destroy(tb_class);
600 }
601
602 module_init(sbprof_tb_init);
603 module_exit(sbprof_tb_cleanup);
604
605 MODULE_ALIAS_CHARDEV_MAJOR(SBPROF_TB_MAJOR);
606 MODULE_AUTHOR("Ralf Baechle <ralf@linux-mips.org>");
607 MODULE_LICENSE("GPL");