2 * Linux on zSeries Channel Measurement Facility support
4 * Copyright IBM Corp. 2000, 2006
6 * Authors: Arnd Bergmann <arndb@de.ibm.com>
7 * Cornelia Huck <cornelia.huck@de.ibm.com>
9 * original idea from Natarajan Krishnaswami <nkrishna@us.ibm.com>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2, or (at your option)
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 #define KMSG_COMPONENT "cio"
27 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
29 #include <linux/bootmem.h>
30 #include <linux/device.h>
31 #include <linux/init.h>
32 #include <linux/list.h>
33 #include <linux/module.h>
34 #include <linux/moduleparam.h>
35 #include <linux/slab.h>
36 #include <linux/timex.h> /* get_tod_clock() */
38 #include <asm/ccwdev.h>
41 #include <asm/div64.h>
50 * parameter to enable cmf during boot, possible uses are:
51 * "s390cmf" -- enable cmf and allocate 2 MB of ram so measuring can be
52 * used on any subchannel
53 * "s390cmf=<num>" -- enable cmf and allocate enough memory to measure
54 * <num> subchannel, where <num> is an integer
55 * between 1 and 65535, default is 1024
57 #define ARGSTRING "s390cmf"
59 /* indices for READCMB */
61 /* basic and exended format: */
64 cmb_device_connect_time,
65 cmb_function_pending_time,
66 cmb_device_disconnect_time,
67 cmb_control_unit_queuing_time,
68 cmb_device_active_only_time,
69 /* extended format only: */
71 cmb_initial_command_response_time,
75 * enum cmb_format - types of supported measurement block formats
77 * @CMF_BASIC: traditional channel measurement blocks supported
78 * by all machines that we run on
79 * @CMF_EXTENDED: improved format that was introduced with the z990
81 * @CMF_AUTODETECT: default: use extended format when running on a machine
82 * supporting extended format, otherwise fall back to
92 * format - actual format for all measurement blocks
94 * The format module parameter can be set to a value of 0 (zero)
95 * or 1, indicating basic or extended format as described for
98 static int format = CMF_AUTODETECT;
99 module_param(format, bint, 0444);
102 * struct cmb_operations - functions to use depending on cmb_format
104 * Most of these functions operate on a struct ccw_device. There is only
105 * one instance of struct cmb_operations because the format of the measurement
106 * data is guaranteed to be the same for every ccw_device.
108 * @alloc: allocate memory for a channel measurement block,
109 * either with the help of a special pool or with kmalloc
110 * @free: free memory allocated with @alloc
111 * @set: enable or disable measurement
112 * @read: read a measurement entry at an index
113 * @readall: read a measurement block in a common format
114 * @reset: clear the data in the associated measurement block and
115 * reset its time stamp
117 struct cmb_operations {
118 int (*alloc) (struct ccw_device *);
119 void (*free) (struct ccw_device *);
120 int (*set) (struct ccw_device *, u32);
121 u64 (*read) (struct ccw_device *, int);
122 int (*readall)(struct ccw_device *, struct cmbdata *);
123 void (*reset) (struct ccw_device *);
125 struct attribute_group *attr_group;
127 static struct cmb_operations *cmbops;
130 void *hw_block; /* Pointer to block updated by hardware */
131 void *last_block; /* Last changed block copied from hardware block */
132 int size; /* Size of hw_block and last_block */
133 unsigned long long last_update; /* when last_block was updated */
137 * Our user interface is designed in terms of nanoseconds,
138 * while the hardware measures total times in its own
141 static inline u64 time_to_nsec(u32 value)
143 return ((u64)value) * 128000ull;
147 * Users are usually interested in average times,
148 * not accumulated time.
149 * This also helps us with atomicity problems
150 * when reading sinlge values.
152 static inline u64 time_to_avg_nsec(u32 value, u32 count)
156 /* no samples yet, avoid division by 0 */
160 /* value comes in units of 128 µsec */
161 ret = time_to_nsec(value);
168 * Activate or deactivate the channel monitor. When area is NULL,
169 * the monitor is deactivated. The channel monitor needs to
170 * be active in order to measure subchannels, which also need
173 static inline void cmf_activate(void *area, unsigned int onoff)
175 register void * __gpr2 asm("2");
176 register long __gpr1 asm("1");
179 __gpr1 = onoff ? 2 : 0;
180 /* activate channel measurement */
181 asm("schm" : : "d" (__gpr2), "d" (__gpr1) );
184 static int set_schib(struct ccw_device *cdev, u32 mme, int mbfc,
185 unsigned long address)
187 struct subchannel *sch = to_subchannel(cdev->dev.parent);
190 sch->config.mme = mme;
191 sch->config.mbfc = mbfc;
192 /* address can be either a block address or a block index */
194 sch->config.mba = address;
196 sch->config.mbi = address;
198 ret = cio_commit_config(sch);
199 if (!mme && ret == -ENODEV) {
201 * The task was to disable measurement block updates but
202 * the subchannel is already gone. Report success.
209 struct set_schib_struct {
212 unsigned long address;
213 wait_queue_head_t wait;
218 static void cmf_set_schib_release(struct kref *kref)
220 struct set_schib_struct *set_data;
222 set_data = container_of(kref, struct set_schib_struct, kref);
226 #define CMF_PENDING 1
228 static int set_schib_wait(struct ccw_device *cdev, u32 mme,
229 int mbfc, unsigned long address)
231 struct set_schib_struct *set_data;
234 spin_lock_irq(cdev->ccwlock);
235 if (!cdev->private->cmb) {
239 set_data = kzalloc(sizeof(struct set_schib_struct), GFP_ATOMIC);
244 init_waitqueue_head(&set_data->wait);
245 kref_init(&set_data->kref);
247 set_data->mbfc = mbfc;
248 set_data->address = address;
250 ret = set_schib(cdev, mme, mbfc, address);
254 if (cdev->private->state != DEV_STATE_ONLINE) {
255 /* if the device is not online, don't even try again */
260 cdev->private->state = DEV_STATE_CMFCHANGE;
261 set_data->ret = CMF_PENDING;
262 cdev->private->cmb_wait = set_data;
264 spin_unlock_irq(cdev->ccwlock);
265 if (wait_event_interruptible(set_data->wait,
266 set_data->ret != CMF_PENDING)) {
267 spin_lock_irq(cdev->ccwlock);
268 if (set_data->ret == CMF_PENDING) {
269 set_data->ret = -ERESTARTSYS;
270 if (cdev->private->state == DEV_STATE_CMFCHANGE)
271 cdev->private->state = DEV_STATE_ONLINE;
273 spin_unlock_irq(cdev->ccwlock);
275 spin_lock_irq(cdev->ccwlock);
276 cdev->private->cmb_wait = NULL;
279 kref_put(&set_data->kref, cmf_set_schib_release);
281 spin_unlock_irq(cdev->ccwlock);
285 void retry_set_schib(struct ccw_device *cdev)
287 struct set_schib_struct *set_data;
289 set_data = cdev->private->cmb_wait;
294 kref_get(&set_data->kref);
295 set_data->ret = set_schib(cdev, set_data->mme, set_data->mbfc,
297 wake_up(&set_data->wait);
298 kref_put(&set_data->kref, cmf_set_schib_release);
301 static int cmf_copy_block(struct ccw_device *cdev)
303 struct subchannel *sch;
306 struct cmb_data *cmb_data;
308 sch = to_subchannel(cdev->dev.parent);
310 if (cio_update_schib(sch))
313 if (scsw_fctl(&sch->schib.scsw) & SCSW_FCTL_START_FUNC) {
314 /* Don't copy if a start function is in progress. */
315 if ((!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_SUSPENDED)) &&
316 (scsw_actl(&sch->schib.scsw) &
317 (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) &&
318 (!(scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_SEC_STATUS)))
321 cmb_data = cdev->private->cmb;
322 hw_block = cmb_data->hw_block;
323 if (!memcmp(cmb_data->last_block, hw_block, cmb_data->size))
324 /* No need to copy. */
326 reference_buf = kzalloc(cmb_data->size, GFP_ATOMIC);
329 /* Ensure consistency of block copied from hardware. */
331 memcpy(cmb_data->last_block, hw_block, cmb_data->size);
332 memcpy(reference_buf, hw_block, cmb_data->size);
333 } while (memcmp(cmb_data->last_block, reference_buf, cmb_data->size));
334 cmb_data->last_update = get_tod_clock();
335 kfree(reference_buf);
339 struct copy_block_struct {
340 wait_queue_head_t wait;
345 static void cmf_copy_block_release(struct kref *kref)
347 struct copy_block_struct *copy_block;
349 copy_block = container_of(kref, struct copy_block_struct, kref);
353 static int cmf_cmb_copy_wait(struct ccw_device *cdev)
355 struct copy_block_struct *copy_block;
359 spin_lock_irqsave(cdev->ccwlock, flags);
360 if (!cdev->private->cmb) {
364 copy_block = kzalloc(sizeof(struct copy_block_struct), GFP_ATOMIC);
369 init_waitqueue_head(©_block->wait);
370 kref_init(©_block->kref);
372 ret = cmf_copy_block(cdev);
376 if (cdev->private->state != DEV_STATE_ONLINE) {
381 cdev->private->state = DEV_STATE_CMFUPDATE;
382 copy_block->ret = CMF_PENDING;
383 cdev->private->cmb_wait = copy_block;
385 spin_unlock_irqrestore(cdev->ccwlock, flags);
386 if (wait_event_interruptible(copy_block->wait,
387 copy_block->ret != CMF_PENDING)) {
388 spin_lock_irqsave(cdev->ccwlock, flags);
389 if (copy_block->ret == CMF_PENDING) {
390 copy_block->ret = -ERESTARTSYS;
391 if (cdev->private->state == DEV_STATE_CMFUPDATE)
392 cdev->private->state = DEV_STATE_ONLINE;
394 spin_unlock_irqrestore(cdev->ccwlock, flags);
396 spin_lock_irqsave(cdev->ccwlock, flags);
397 cdev->private->cmb_wait = NULL;
398 ret = copy_block->ret;
400 kref_put(©_block->kref, cmf_copy_block_release);
402 spin_unlock_irqrestore(cdev->ccwlock, flags);
406 void cmf_retry_copy_block(struct ccw_device *cdev)
408 struct copy_block_struct *copy_block;
410 copy_block = cdev->private->cmb_wait;
415 kref_get(©_block->kref);
416 copy_block->ret = cmf_copy_block(cdev);
417 wake_up(©_block->wait);
418 kref_put(©_block->kref, cmf_copy_block_release);
421 static void cmf_generic_reset(struct ccw_device *cdev)
423 struct cmb_data *cmb_data;
425 spin_lock_irq(cdev->ccwlock);
426 cmb_data = cdev->private->cmb;
428 memset(cmb_data->last_block, 0, cmb_data->size);
430 * Need to reset hw block as well to make the hardware start
433 memset(cmb_data->hw_block, 0, cmb_data->size);
434 cmb_data->last_update = 0;
436 cdev->private->cmb_start_time = get_tod_clock();
437 spin_unlock_irq(cdev->ccwlock);
441 * struct cmb_area - container for global cmb data
443 * @mem: pointer to CMBs (only in basic measurement mode)
444 * @list: contains a linked list of all subchannels
445 * @num_channels: number of channels to be measured
446 * @lock: protect concurrent access to @mem and @list
450 struct list_head list;
455 static struct cmb_area cmb_area = {
456 .lock = __SPIN_LOCK_UNLOCKED(cmb_area.lock),
457 .list = LIST_HEAD_INIT(cmb_area.list),
458 .num_channels = 1024,
461 /* ****** old style CMB handling ********/
464 * Basic channel measurement blocks are allocated in one contiguous
465 * block of memory, which can not be moved as long as any channel
466 * is active. Therefore, a maximum number of subchannels needs to
467 * be defined somewhere. This is a module parameter, defaulting to
468 * a reasonable value of 1024, or 32 kb of memory.
469 * Current kernels don't allow kmalloc with more than 128kb, so the
473 module_param_named(maxchannels, cmb_area.num_channels, uint, 0444);
476 * struct cmb - basic channel measurement block
477 * @ssch_rsch_count: number of ssch and rsch
478 * @sample_count: number of samples
479 * @device_connect_time: time of device connect
480 * @function_pending_time: time of function pending
481 * @device_disconnect_time: time of device disconnect
482 * @control_unit_queuing_time: time of control unit queuing
483 * @device_active_only_time: time of device active only
484 * @reserved: unused in basic measurement mode
486 * The measurement block as used by the hardware. The fields are described
487 * further in z/Architecture Principles of Operation, chapter 17.
489 * The cmb area made up from these blocks must be a contiguous array and may
490 * not be reallocated or freed.
491 * Only one cmb area can be present in the system.
496 u32 device_connect_time;
497 u32 function_pending_time;
498 u32 device_disconnect_time;
499 u32 control_unit_queuing_time;
500 u32 device_active_only_time;
505 * Insert a single device into the cmb_area list.
506 * Called with cmb_area.lock held from alloc_cmb.
508 static int alloc_cmb_single(struct ccw_device *cdev,
509 struct cmb_data *cmb_data)
512 struct ccw_device_private *node;
515 spin_lock_irq(cdev->ccwlock);
516 if (!list_empty(&cdev->private->cmb_list)) {
522 * Find first unused cmb in cmb_area.mem.
523 * This is a little tricky: cmb_area.list
524 * remains sorted by ->cmb->hw_data pointers.
527 list_for_each_entry(node, &cmb_area.list, cmb_list) {
528 struct cmb_data *data;
530 if ((struct cmb*)data->hw_block > cmb)
534 if (cmb - cmb_area.mem >= cmb_area.num_channels) {
540 list_add_tail(&cdev->private->cmb_list, &node->cmb_list);
541 cmb_data->hw_block = cmb;
542 cdev->private->cmb = cmb_data;
545 spin_unlock_irq(cdev->ccwlock);
549 static int alloc_cmb(struct ccw_device *cdev)
554 struct cmb_data *cmb_data;
556 /* Allocate private cmb_data. */
557 cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
561 cmb_data->last_block = kzalloc(sizeof(struct cmb), GFP_KERNEL);
562 if (!cmb_data->last_block) {
566 cmb_data->size = sizeof(struct cmb);
567 spin_lock(&cmb_area.lock);
570 /* there is no user yet, so we need a new area */
571 size = sizeof(struct cmb) * cmb_area.num_channels;
572 WARN_ON(!list_empty(&cmb_area.list));
574 spin_unlock(&cmb_area.lock);
575 mem = (void*)__get_free_pages(GFP_KERNEL | GFP_DMA,
577 spin_lock(&cmb_area.lock);
580 /* ok, another thread was faster */
581 free_pages((unsigned long)mem, get_order(size));
588 memset(mem, 0, size);
590 cmf_activate(cmb_area.mem, 1);
594 /* do the actual allocation */
595 ret = alloc_cmb_single(cdev, cmb_data);
597 spin_unlock(&cmb_area.lock);
599 kfree(cmb_data->last_block);
605 static void free_cmb(struct ccw_device *cdev)
607 struct ccw_device_private *priv;
608 struct cmb_data *cmb_data;
610 spin_lock(&cmb_area.lock);
611 spin_lock_irq(cdev->ccwlock);
613 priv = cdev->private;
614 cmb_data = priv->cmb;
617 kfree(cmb_data->last_block);
619 list_del_init(&priv->cmb_list);
621 if (list_empty(&cmb_area.list)) {
623 size = sizeof(struct cmb) * cmb_area.num_channels;
624 cmf_activate(NULL, 0);
625 free_pages((unsigned long)cmb_area.mem, get_order(size));
628 spin_unlock_irq(cdev->ccwlock);
629 spin_unlock(&cmb_area.lock);
632 static int set_cmb(struct ccw_device *cdev, u32 mme)
635 struct cmb_data *cmb_data;
638 spin_lock_irqsave(cdev->ccwlock, flags);
639 if (!cdev->private->cmb) {
640 spin_unlock_irqrestore(cdev->ccwlock, flags);
643 cmb_data = cdev->private->cmb;
644 offset = mme ? (struct cmb *)cmb_data->hw_block - cmb_area.mem : 0;
645 spin_unlock_irqrestore(cdev->ccwlock, flags);
647 return set_schib_wait(cdev, mme, 0, offset);
650 static u64 read_cmb(struct ccw_device *cdev, int index)
657 ret = cmf_cmb_copy_wait(cdev);
661 spin_lock_irqsave(cdev->ccwlock, flags);
662 if (!cdev->private->cmb) {
666 cmb = ((struct cmb_data *)cdev->private->cmb)->last_block;
669 case cmb_ssch_rsch_count:
670 ret = cmb->ssch_rsch_count;
672 case cmb_sample_count:
673 ret = cmb->sample_count;
675 case cmb_device_connect_time:
676 val = cmb->device_connect_time;
678 case cmb_function_pending_time:
679 val = cmb->function_pending_time;
681 case cmb_device_disconnect_time:
682 val = cmb->device_disconnect_time;
684 case cmb_control_unit_queuing_time:
685 val = cmb->control_unit_queuing_time;
687 case cmb_device_active_only_time:
688 val = cmb->device_active_only_time;
694 ret = time_to_avg_nsec(val, cmb->sample_count);
696 spin_unlock_irqrestore(cdev->ccwlock, flags);
700 static int readall_cmb(struct ccw_device *cdev, struct cmbdata *data)
703 struct cmb_data *cmb_data;
708 ret = cmf_cmb_copy_wait(cdev);
711 spin_lock_irqsave(cdev->ccwlock, flags);
712 cmb_data = cdev->private->cmb;
717 if (cmb_data->last_update == 0) {
721 cmb = cmb_data->last_block;
722 time = cmb_data->last_update - cdev->private->cmb_start_time;
724 memset(data, 0, sizeof(struct cmbdata));
726 /* we only know values before device_busy_time */
727 data->size = offsetof(struct cmbdata, device_busy_time);
729 /* convert to nanoseconds */
730 data->elapsed_time = (time * 1000) >> 12;
732 /* copy data to new structure */
733 data->ssch_rsch_count = cmb->ssch_rsch_count;
734 data->sample_count = cmb->sample_count;
736 /* time fields are converted to nanoseconds while copying */
737 data->device_connect_time = time_to_nsec(cmb->device_connect_time);
738 data->function_pending_time = time_to_nsec(cmb->function_pending_time);
739 data->device_disconnect_time =
740 time_to_nsec(cmb->device_disconnect_time);
741 data->control_unit_queuing_time
742 = time_to_nsec(cmb->control_unit_queuing_time);
743 data->device_active_only_time
744 = time_to_nsec(cmb->device_active_only_time);
747 spin_unlock_irqrestore(cdev->ccwlock, flags);
751 static void reset_cmb(struct ccw_device *cdev)
753 cmf_generic_reset(cdev);
756 static struct attribute_group cmf_attr_group;
758 static struct cmb_operations cmbops_basic = {
763 .readall = readall_cmb,
765 .attr_group = &cmf_attr_group,
768 /* ******** extended cmb handling ********/
771 * struct cmbe - extended channel measurement block
772 * @ssch_rsch_count: number of ssch and rsch
773 * @sample_count: number of samples
774 * @device_connect_time: time of device connect
775 * @function_pending_time: time of function pending
776 * @device_disconnect_time: time of device disconnect
777 * @control_unit_queuing_time: time of control unit queuing
778 * @device_active_only_time: time of device active only
779 * @device_busy_time: time of device busy
780 * @initial_command_response_time: initial command response time
783 * The measurement block as used by the hardware. May be in any 64 bit physical
785 * The fields are described further in z/Architecture Principles of Operation,
786 * third edition, chapter 17.
791 u32 device_connect_time;
792 u32 function_pending_time;
793 u32 device_disconnect_time;
794 u32 control_unit_queuing_time;
795 u32 device_active_only_time;
796 u32 device_busy_time;
797 u32 initial_command_response_time;
799 } __packed __aligned(64);
801 static struct kmem_cache *cmbe_cache;
803 static int alloc_cmbe(struct ccw_device *cdev)
805 struct cmb_data *cmb_data;
809 cmbe = kmem_cache_zalloc(cmbe_cache, GFP_KERNEL);
813 cmb_data = kzalloc(sizeof(*cmb_data), GFP_KERNEL);
817 cmb_data->last_block = kzalloc(sizeof(struct cmbe), GFP_KERNEL);
818 if (!cmb_data->last_block)
821 cmb_data->size = sizeof(*cmbe);
822 cmb_data->hw_block = cmbe;
824 spin_lock(&cmb_area.lock);
825 spin_lock_irq(cdev->ccwlock);
826 if (cdev->private->cmb)
829 cdev->private->cmb = cmb_data;
831 /* activate global measurement if this is the first channel */
832 if (list_empty(&cmb_area.list))
833 cmf_activate(NULL, 1);
834 list_add_tail(&cdev->private->cmb_list, &cmb_area.list);
836 spin_unlock_irq(cdev->ccwlock);
837 spin_unlock(&cmb_area.lock);
841 spin_unlock_irq(cdev->ccwlock);
842 spin_unlock(&cmb_area.lock);
846 kfree(cmb_data->last_block);
848 kmem_cache_free(cmbe_cache, cmbe);
853 static void free_cmbe(struct ccw_device *cdev)
855 struct cmb_data *cmb_data;
857 spin_lock(&cmb_area.lock);
858 spin_lock_irq(cdev->ccwlock);
859 cmb_data = cdev->private->cmb;
860 cdev->private->cmb = NULL;
862 kfree(cmb_data->last_block);
863 kmem_cache_free(cmbe_cache, cmb_data->hw_block);
867 /* deactivate global measurement if this is the last channel */
868 list_del_init(&cdev->private->cmb_list);
869 if (list_empty(&cmb_area.list))
870 cmf_activate(NULL, 0);
871 spin_unlock_irq(cdev->ccwlock);
872 spin_unlock(&cmb_area.lock);
875 static int set_cmbe(struct ccw_device *cdev, u32 mme)
878 struct cmb_data *cmb_data;
881 spin_lock_irqsave(cdev->ccwlock, flags);
882 if (!cdev->private->cmb) {
883 spin_unlock_irqrestore(cdev->ccwlock, flags);
886 cmb_data = cdev->private->cmb;
887 mba = mme ? (unsigned long) cmb_data->hw_block : 0;
888 spin_unlock_irqrestore(cdev->ccwlock, flags);
890 return set_schib_wait(cdev, mme, 1, mba);
894 static u64 read_cmbe(struct ccw_device *cdev, int index)
897 struct cmb_data *cmb_data;
902 ret = cmf_cmb_copy_wait(cdev);
906 spin_lock_irqsave(cdev->ccwlock, flags);
907 cmb_data = cdev->private->cmb;
912 cmb = cmb_data->last_block;
915 case cmb_ssch_rsch_count:
916 ret = cmb->ssch_rsch_count;
918 case cmb_sample_count:
919 ret = cmb->sample_count;
921 case cmb_device_connect_time:
922 val = cmb->device_connect_time;
924 case cmb_function_pending_time:
925 val = cmb->function_pending_time;
927 case cmb_device_disconnect_time:
928 val = cmb->device_disconnect_time;
930 case cmb_control_unit_queuing_time:
931 val = cmb->control_unit_queuing_time;
933 case cmb_device_active_only_time:
934 val = cmb->device_active_only_time;
936 case cmb_device_busy_time:
937 val = cmb->device_busy_time;
939 case cmb_initial_command_response_time:
940 val = cmb->initial_command_response_time;
946 ret = time_to_avg_nsec(val, cmb->sample_count);
948 spin_unlock_irqrestore(cdev->ccwlock, flags);
952 static int readall_cmbe(struct ccw_device *cdev, struct cmbdata *data)
955 struct cmb_data *cmb_data;
960 ret = cmf_cmb_copy_wait(cdev);
963 spin_lock_irqsave(cdev->ccwlock, flags);
964 cmb_data = cdev->private->cmb;
969 if (cmb_data->last_update == 0) {
973 time = cmb_data->last_update - cdev->private->cmb_start_time;
975 memset (data, 0, sizeof(struct cmbdata));
977 /* we only know values before device_busy_time */
978 data->size = offsetof(struct cmbdata, device_busy_time);
980 /* conver to nanoseconds */
981 data->elapsed_time = (time * 1000) >> 12;
983 cmb = cmb_data->last_block;
984 /* copy data to new structure */
985 data->ssch_rsch_count = cmb->ssch_rsch_count;
986 data->sample_count = cmb->sample_count;
988 /* time fields are converted to nanoseconds while copying */
989 data->device_connect_time = time_to_nsec(cmb->device_connect_time);
990 data->function_pending_time = time_to_nsec(cmb->function_pending_time);
991 data->device_disconnect_time =
992 time_to_nsec(cmb->device_disconnect_time);
993 data->control_unit_queuing_time
994 = time_to_nsec(cmb->control_unit_queuing_time);
995 data->device_active_only_time
996 = time_to_nsec(cmb->device_active_only_time);
997 data->device_busy_time = time_to_nsec(cmb->device_busy_time);
998 data->initial_command_response_time
999 = time_to_nsec(cmb->initial_command_response_time);
1003 spin_unlock_irqrestore(cdev->ccwlock, flags);
1007 static void reset_cmbe(struct ccw_device *cdev)
1009 cmf_generic_reset(cdev);
1012 static struct attribute_group cmf_attr_group_ext;
1014 static struct cmb_operations cmbops_extended = {
1015 .alloc = alloc_cmbe,
1019 .readall = readall_cmbe,
1020 .reset = reset_cmbe,
1021 .attr_group = &cmf_attr_group_ext,
1024 static ssize_t cmb_show_attr(struct device *dev, char *buf, enum cmb_index idx)
1026 return sprintf(buf, "%lld\n",
1027 (unsigned long long) cmf_read(to_ccwdev(dev), idx));
1030 static ssize_t cmb_show_avg_sample_interval(struct device *dev,
1031 struct device_attribute *attr,
1034 struct ccw_device *cdev;
1036 unsigned long count;
1037 struct cmb_data *cmb_data;
1039 cdev = to_ccwdev(dev);
1040 count = cmf_read(cdev, cmb_sample_count);
1041 spin_lock_irq(cdev->ccwlock);
1042 cmb_data = cdev->private->cmb;
1044 interval = cmb_data->last_update -
1045 cdev->private->cmb_start_time;
1046 interval = (interval * 1000) >> 12;
1050 spin_unlock_irq(cdev->ccwlock);
1051 return sprintf(buf, "%ld\n", interval);
1054 static ssize_t cmb_show_avg_utilization(struct device *dev,
1055 struct device_attribute *attr,
1058 struct cmbdata data;
1063 ret = cmf_readall(to_ccwdev(dev), &data);
1064 if (ret == -EAGAIN || ret == -ENODEV)
1065 /* No data (yet/currently) available to use for calculation. */
1066 return sprintf(buf, "n/a\n");
1070 utilization = data.device_connect_time +
1071 data.function_pending_time +
1072 data.device_disconnect_time;
1074 /* shift to avoid long long division */
1075 while (-1ul < (data.elapsed_time | utilization)) {
1077 data.elapsed_time >>= 8;
1080 /* calculate value in 0.1 percent units */
1081 t = (unsigned long) data.elapsed_time / 1000;
1082 u = (unsigned long) utilization / t;
1084 return sprintf(buf, "%02ld.%01ld%%\n", u/ 10, u - (u/ 10) * 10);
1087 #define cmf_attr(name) \
1088 static ssize_t show_##name(struct device *dev, \
1089 struct device_attribute *attr, char *buf) \
1090 { return cmb_show_attr((dev), buf, cmb_##name); } \
1091 static DEVICE_ATTR(name, 0444, show_##name, NULL);
1093 #define cmf_attr_avg(name) \
1094 static ssize_t show_avg_##name(struct device *dev, \
1095 struct device_attribute *attr, char *buf) \
1096 { return cmb_show_attr((dev), buf, cmb_##name); } \
1097 static DEVICE_ATTR(avg_##name, 0444, show_avg_##name, NULL);
1099 cmf_attr(ssch_rsch_count);
1100 cmf_attr(sample_count);
1101 cmf_attr_avg(device_connect_time);
1102 cmf_attr_avg(function_pending_time);
1103 cmf_attr_avg(device_disconnect_time);
1104 cmf_attr_avg(control_unit_queuing_time);
1105 cmf_attr_avg(device_active_only_time);
1106 cmf_attr_avg(device_busy_time);
1107 cmf_attr_avg(initial_command_response_time);
1109 static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval,
1111 static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL);
1113 static struct attribute *cmf_attributes[] = {
1114 &dev_attr_avg_sample_interval.attr,
1115 &dev_attr_avg_utilization.attr,
1116 &dev_attr_ssch_rsch_count.attr,
1117 &dev_attr_sample_count.attr,
1118 &dev_attr_avg_device_connect_time.attr,
1119 &dev_attr_avg_function_pending_time.attr,
1120 &dev_attr_avg_device_disconnect_time.attr,
1121 &dev_attr_avg_control_unit_queuing_time.attr,
1122 &dev_attr_avg_device_active_only_time.attr,
1126 static struct attribute_group cmf_attr_group = {
1128 .attrs = cmf_attributes,
1131 static struct attribute *cmf_attributes_ext[] = {
1132 &dev_attr_avg_sample_interval.attr,
1133 &dev_attr_avg_utilization.attr,
1134 &dev_attr_ssch_rsch_count.attr,
1135 &dev_attr_sample_count.attr,
1136 &dev_attr_avg_device_connect_time.attr,
1137 &dev_attr_avg_function_pending_time.attr,
1138 &dev_attr_avg_device_disconnect_time.attr,
1139 &dev_attr_avg_control_unit_queuing_time.attr,
1140 &dev_attr_avg_device_active_only_time.attr,
1141 &dev_attr_avg_device_busy_time.attr,
1142 &dev_attr_avg_initial_command_response_time.attr,
1146 static struct attribute_group cmf_attr_group_ext = {
1148 .attrs = cmf_attributes_ext,
1151 static ssize_t cmb_enable_show(struct device *dev,
1152 struct device_attribute *attr,
1155 struct ccw_device *cdev = to_ccwdev(dev);
1158 spin_lock_irq(cdev->ccwlock);
1159 enabled = !!cdev->private->cmb;
1160 spin_unlock_irq(cdev->ccwlock);
1162 return sprintf(buf, "%d\n", enabled);
1165 static ssize_t cmb_enable_store(struct device *dev,
1166 struct device_attribute *attr, const char *buf,
1169 struct ccw_device *cdev = to_ccwdev(dev);
1173 ret = kstrtoul(buf, 16, &val);
1179 ret = disable_cmf(cdev);
1182 ret = enable_cmf(cdev);
1188 return ret ? ret : c;
1190 DEVICE_ATTR_RW(cmb_enable);
1192 int ccw_set_cmf(struct ccw_device *cdev, int enable)
1194 return cmbops->set(cdev, enable ? 2 : 0);
1198 * enable_cmf() - switch on the channel measurement for a specific device
1199 * @cdev: The ccw device to be enabled
1201 * Returns %0 for success or a negative error value.
1206 int enable_cmf(struct ccw_device *cdev)
1210 device_lock(&cdev->dev);
1211 get_device(&cdev->dev);
1212 ret = cmbops->alloc(cdev);
1215 cmbops->reset(cdev);
1216 ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
1221 ret = cmbops->set(cdev, 2);
1223 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
1228 put_device(&cdev->dev);
1230 device_unlock(&cdev->dev);
1235 * __disable_cmf() - switch off the channel measurement for a specific device
1236 * @cdev: The ccw device to be disabled
1238 * Returns %0 for success or a negative error value.
1241 * non-atomic, device_lock() held.
1243 int __disable_cmf(struct ccw_device *cdev)
1247 ret = cmbops->set(cdev, 0);
1251 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
1253 put_device(&cdev->dev);
1259 * disable_cmf() - switch off the channel measurement for a specific device
1260 * @cdev: The ccw device to be disabled
1262 * Returns %0 for success or a negative error value.
1267 int disable_cmf(struct ccw_device *cdev)
1271 device_lock(&cdev->dev);
1272 ret = __disable_cmf(cdev);
1273 device_unlock(&cdev->dev);
1279 * cmf_read() - read one value from the current channel measurement block
1280 * @cdev: the channel to be read
1281 * @index: the index of the value to be read
1283 * Returns the value read or %0 if the value cannot be read.
1288 u64 cmf_read(struct ccw_device *cdev, int index)
1290 return cmbops->read(cdev, index);
1294 * cmf_readall() - read the current channel measurement block
1295 * @cdev: the channel to be read
1296 * @data: a pointer to a data block that will be filled
1298 * Returns %0 on success, a negative error value otherwise.
1303 int cmf_readall(struct ccw_device *cdev, struct cmbdata *data)
1305 return cmbops->readall(cdev, data);
1308 /* Reenable cmf when a disconnected device becomes available again. */
1309 int cmf_reenable(struct ccw_device *cdev)
1311 cmbops->reset(cdev);
1312 return cmbops->set(cdev, 2);
1316 * cmf_reactivate() - reactivate measurement block updates
1318 * Use this during resume from hibernate.
1320 void cmf_reactivate(void)
1322 spin_lock(&cmb_area.lock);
1323 if (!list_empty(&cmb_area.list))
1324 cmf_activate(cmb_area.mem, 1);
1325 spin_unlock(&cmb_area.lock);
1328 static int __init init_cmbe(void)
1330 cmbe_cache = kmem_cache_create("cmbe_cache", sizeof(struct cmbe),
1331 __alignof__(struct cmbe), 0, NULL);
1333 return cmbe_cache ? 0 : -ENOMEM;
1336 static int __init init_cmf(void)
1338 char *format_string;
1339 char *detect_string;
1343 * If the user did not give a parameter, see if we are running on a
1344 * machine supporting extended measurement blocks, otherwise fall back
1347 if (format == CMF_AUTODETECT) {
1348 if (!css_general_characteristics.ext_mb) {
1351 format = CMF_EXTENDED;
1353 detect_string = "autodetected";
1355 detect_string = "parameter";
1360 format_string = "basic";
1361 cmbops = &cmbops_basic;
1364 format_string = "extended";
1365 cmbops = &cmbops_extended;
1374 pr_info("Channel measurement facility initialized using format "
1375 "%s (mode %s)\n", format_string, detect_string);
1378 module_init(init_cmf);
1381 MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
1382 MODULE_LICENSE("GPL");
1383 MODULE_DESCRIPTION("channel measurement facility base driver\n"
1384 "Copyright IBM Corp. 2003\n");
1386 EXPORT_SYMBOL_GPL(enable_cmf);
1387 EXPORT_SYMBOL_GPL(disable_cmf);
1388 EXPORT_SYMBOL_GPL(cmf_read);
1389 EXPORT_SYMBOL_GPL(cmf_readall);