1 // SPDX-License-Identifier: GPL-2.0
3 * core function to access sclp interface
5 * Copyright IBM Corp. 1999, 2009
7 * Author(s): Martin Peschke <mpeschke@de.ibm.com>
8 * Martin Schwidefsky <schwidefsky@de.ibm.com>
11 #include <linux/kernel_stat.h>
12 #include <linux/module.h>
13 #include <linux/err.h>
14 #include <linux/panic_notifier.h>
15 #include <linux/spinlock.h>
16 #include <linux/interrupt.h>
17 #include <linux/timer.h>
18 #include <linux/reboot.h>
19 #include <linux/jiffies.h>
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <asm/types.h>
24 #include <asm/debug.h>
28 #define SCLP_HEADER "sclp: "
30 struct sclp_trace_entry {
31 char id[4] __nonstring;
36 #define SCLP_TRACE_ENTRY_SIZE sizeof(struct sclp_trace_entry)
37 #define SCLP_TRACE_MAX_SIZE 128
38 #define SCLP_TRACE_EVENT_MAX_SIZE 64
40 /* Debug trace area intended for all entries in abbreviated form. */
41 DEFINE_STATIC_DEBUG_INFO(sclp_debug, "sclp", 8, 1, SCLP_TRACE_ENTRY_SIZE,
42 &debug_hex_ascii_view);
44 /* Error trace area intended for full entries relating to failed requests. */
45 DEFINE_STATIC_DEBUG_INFO(sclp_debug_err, "sclp_err", 4, 1,
46 SCLP_TRACE_ENTRY_SIZE, &debug_hex_ascii_view);
48 /* Lock to protect internal data consistency. */
49 static DEFINE_SPINLOCK(sclp_lock);
51 /* Mask of events that we can send to the sclp interface. */
52 static sccb_mask_t sclp_receive_mask;
54 /* Mask of events that we can receive from the sclp interface. */
55 static sccb_mask_t sclp_send_mask;
57 /* List of registered event listeners and senders. */
58 static LIST_HEAD(sclp_reg_list);
60 /* List of queued requests. */
61 static LIST_HEAD(sclp_req_queue);
63 /* Data for read and init requests. */
64 static struct sclp_req sclp_read_req;
65 static struct sclp_req sclp_init_req;
66 static void *sclp_read_sccb;
67 static struct init_sccb *sclp_init_sccb;
69 /* Number of console pages to allocate, used by sclp_con.c and sclp_vt220.c */
70 int sclp_console_pages = SCLP_CONSOLE_PAGES;
71 /* Flag to indicate if buffer pages are dropped on buffer full condition */
72 int sclp_console_drop = 1;
73 /* Number of times the console dropped buffer pages */
74 unsigned long sclp_console_full;
76 /* The currently active SCLP command word. */
77 static sclp_cmdw_t active_cmd;
79 static inline void sclp_trace(int prio, char *id, u32 a, u64 b, bool err)
81 struct sclp_trace_entry e;
83 memset(&e, 0, sizeof(e));
84 strncpy(e.id, id, sizeof(e.id));
87 debug_event(&sclp_debug, prio, &e, sizeof(e));
89 debug_event(&sclp_debug_err, 0, &e, sizeof(e));
92 static inline int no_zeroes_len(void *data, int len)
96 /* Minimize trace area usage by not tracing trailing zeroes. */
97 while (len > SCLP_TRACE_ENTRY_SIZE && d[len - 1] == 0)
103 static inline void sclp_trace_bin(int prio, void *d, int len, int errlen)
105 debug_event(&sclp_debug, prio, d, no_zeroes_len(d, len));
107 debug_event(&sclp_debug_err, 0, d, no_zeroes_len(d, errlen));
110 static inline int abbrev_len(sclp_cmdw_t cmd, struct sccb_header *sccb)
112 struct evbuf_header *evbuf = (struct evbuf_header *)(sccb + 1);
113 int len = sccb->length, limit = SCLP_TRACE_MAX_SIZE;
115 /* Full SCCB tracing if debug level is set to max. */
116 if (sclp_debug.level == DEBUG_MAX_LEVEL)
119 /* Minimal tracing for console writes. */
120 if (cmd == SCLP_CMDW_WRITE_EVENT_DATA &&
121 (evbuf->type == EVTYP_MSG || evbuf->type == EVTYP_VT220MSG))
122 limit = SCLP_TRACE_ENTRY_SIZE;
124 return min(len, limit);
127 static inline void sclp_trace_sccb(int prio, char *id, u32 a, u64 b,
128 sclp_cmdw_t cmd, struct sccb_header *sccb,
131 sclp_trace(prio, id, a, b, err);
133 sclp_trace_bin(prio + 1, sccb, abbrev_len(cmd, sccb),
134 err ? sccb->length : 0);
138 static inline void sclp_trace_evbuf(int prio, char *id, u32 a, u64 b,
139 struct evbuf_header *evbuf, bool err)
141 sclp_trace(prio, id, a, b, err);
142 sclp_trace_bin(prio + 1, evbuf,
143 min((int)evbuf->length, (int)SCLP_TRACE_EVENT_MAX_SIZE),
144 err ? evbuf->length : 0);
147 static inline void sclp_trace_req(int prio, char *id, struct sclp_req *req,
150 struct sccb_header *sccb = req->sccb;
161 summary.status = req->status;
162 summary.response = sccb ? sccb->response_code : 0;
163 summary.timeout = (u16)req->queue_timeout;
164 summary.start_count = (u16)req->start_count;
166 sclp_trace(prio, id, __pa(sccb), summary.b, err);
169 static inline void sclp_trace_register(int prio, char *id, u32 a, u64 b,
170 struct sclp_register *reg)
177 d.receive = reg->receive_mask;
178 d.send = reg->send_mask;
180 sclp_trace(prio, id, a, b, false);
181 sclp_trace_bin(prio, &d, sizeof(d), 0);
184 static int __init sclp_setup_console_pages(char *str)
188 rc = kstrtoint(str, 0, &pages);
189 if (!rc && pages >= SCLP_CONSOLE_PAGES)
190 sclp_console_pages = pages;
194 __setup("sclp_con_pages=", sclp_setup_console_pages);
196 static int __init sclp_setup_console_drop(char *str)
200 rc = kstrtoint(str, 0, &drop);
202 sclp_console_drop = drop;
206 __setup("sclp_con_drop=", sclp_setup_console_drop);
208 /* Timer for request retries. */
209 static struct timer_list sclp_request_timer;
211 /* Timer for queued requests. */
212 static struct timer_list sclp_queue_timer;
214 /* Internal state: is a request active at the sclp? */
215 static volatile enum sclp_running_state_t {
216 sclp_running_state_idle,
217 sclp_running_state_running,
218 sclp_running_state_reset_pending
219 } sclp_running_state = sclp_running_state_idle;
221 /* Internal state: is a read request pending? */
222 static volatile enum sclp_reading_state_t {
223 sclp_reading_state_idle,
224 sclp_reading_state_reading
225 } sclp_reading_state = sclp_reading_state_idle;
227 /* Internal state: is the driver currently serving requests? */
228 static volatile enum sclp_activation_state_t {
229 sclp_activation_state_active,
230 sclp_activation_state_deactivating,
231 sclp_activation_state_inactive,
232 sclp_activation_state_activating
233 } sclp_activation_state = sclp_activation_state_active;
235 /* Internal state: is an init mask request pending? */
236 static volatile enum sclp_mask_state_t {
237 sclp_mask_state_idle,
238 sclp_mask_state_initializing
239 } sclp_mask_state = sclp_mask_state_idle;
241 /* Maximum retry counts */
242 #define SCLP_INIT_RETRY 3
243 #define SCLP_MASK_RETRY 3
245 /* Timeout intervals in seconds.*/
246 #define SCLP_BUSY_INTERVAL 10
247 #define SCLP_RETRY_INTERVAL 30
249 static void sclp_request_timeout(bool force_restart);
250 static void sclp_process_queue(void);
251 static void __sclp_make_read_req(void);
252 static int sclp_init_mask(int calculate);
253 static int sclp_init(void);
256 __sclp_queue_read_req(void)
258 if (sclp_reading_state == sclp_reading_state_idle) {
259 sclp_reading_state = sclp_reading_state_reading;
260 __sclp_make_read_req();
261 /* Add request to head of queue */
262 list_add(&sclp_read_req.list, &sclp_req_queue);
266 /* Set up request retry timer. Called while sclp_lock is locked. */
268 __sclp_set_request_timer(unsigned long time, void (*cb)(struct timer_list *))
270 del_timer(&sclp_request_timer);
271 sclp_request_timer.function = cb;
272 sclp_request_timer.expires = jiffies + time;
273 add_timer(&sclp_request_timer);
276 static void sclp_request_timeout_restart(struct timer_list *unused)
278 sclp_request_timeout(true);
281 static void sclp_request_timeout_normal(struct timer_list *unused)
283 sclp_request_timeout(false);
286 /* Request timeout handler. Restart the request queue. If force_restart,
287 * force restart of running request. */
288 static void sclp_request_timeout(bool force_restart)
292 /* TMO: A timeout occurred (a=force_restart) */
293 sclp_trace(2, "TMO", force_restart, 0, true);
295 spin_lock_irqsave(&sclp_lock, flags);
297 if (sclp_running_state == sclp_running_state_running) {
298 /* Break running state and queue NOP read event request
299 * to get a defined interface state. */
300 __sclp_queue_read_req();
301 sclp_running_state = sclp_running_state_idle;
304 __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ,
305 sclp_request_timeout_normal);
307 spin_unlock_irqrestore(&sclp_lock, flags);
308 sclp_process_queue();
312 * Returns the expire value in jiffies of the next pending request timeout,
313 * if any. Needs to be called with sclp_lock.
315 static unsigned long __sclp_req_queue_find_next_timeout(void)
317 unsigned long expires_next = 0;
318 struct sclp_req *req;
320 list_for_each_entry(req, &sclp_req_queue, list) {
321 if (!req->queue_expires)
324 (time_before(req->queue_expires, expires_next)))
325 expires_next = req->queue_expires;
331 * Returns expired request, if any, and removes it from the list.
333 static struct sclp_req *__sclp_req_queue_remove_expired_req(void)
335 unsigned long flags, now;
336 struct sclp_req *req;
338 spin_lock_irqsave(&sclp_lock, flags);
340 /* Don't need list_for_each_safe because we break out after list_del */
341 list_for_each_entry(req, &sclp_req_queue, list) {
342 if (!req->queue_expires)
344 if (time_before_eq(req->queue_expires, now)) {
345 if (req->status == SCLP_REQ_QUEUED) {
346 req->status = SCLP_REQ_QUEUED_TIMEOUT;
347 list_del(&req->list);
354 spin_unlock_irqrestore(&sclp_lock, flags);
359 * Timeout handler for queued requests. Removes request from list and
360 * invokes callback. This timer can be set per request in situations where
361 * waiting too long would be harmful to the system, e.g. during SE reboot.
363 static void sclp_req_queue_timeout(struct timer_list *unused)
365 unsigned long flags, expires_next;
366 struct sclp_req *req;
369 req = __sclp_req_queue_remove_expired_req();
372 /* RQTM: Request timed out (a=sccb, b=summary) */
373 sclp_trace_req(2, "RQTM", req, true);
376 if (req && req->callback)
377 req->callback(req, req->callback_data);
380 spin_lock_irqsave(&sclp_lock, flags);
381 expires_next = __sclp_req_queue_find_next_timeout();
383 mod_timer(&sclp_queue_timer, expires_next);
384 spin_unlock_irqrestore(&sclp_lock, flags);
387 static int sclp_service_call_trace(sclp_cmdw_t command, void *sccb)
389 static u64 srvc_count;
392 /* SRV1: Service call about to be issued (a=command, b=sccb address) */
393 sclp_trace_sccb(0, "SRV1", command, (u64)sccb, command, sccb, false);
395 rc = sclp_service_call(command, sccb);
397 /* SRV2: Service call was issued (a=rc, b=SRVC sequence number) */
398 sclp_trace(0, "SRV2", -rc, ++srvc_count, rc != 0);
401 active_cmd = command;
406 /* Try to start a request. Return zero if the request was successfully
407 * started or if it will be started at a later time. Return non-zero otherwise.
408 * Called while sclp_lock is locked. */
410 __sclp_start_request(struct sclp_req *req)
414 if (sclp_running_state != sclp_running_state_idle)
416 del_timer(&sclp_request_timer);
417 rc = sclp_service_call_trace(req->command, req->sccb);
421 /* Successfully started request */
422 req->status = SCLP_REQ_RUNNING;
423 sclp_running_state = sclp_running_state_running;
424 __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ,
425 sclp_request_timeout_restart);
427 } else if (rc == -EBUSY) {
428 /* Try again later */
429 __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ,
430 sclp_request_timeout_normal);
434 req->status = SCLP_REQ_FAILED;
438 /* Try to start queued requests. */
440 sclp_process_queue(void)
442 struct sclp_req *req;
446 spin_lock_irqsave(&sclp_lock, flags);
447 if (sclp_running_state != sclp_running_state_idle) {
448 spin_unlock_irqrestore(&sclp_lock, flags);
451 del_timer(&sclp_request_timer);
452 while (!list_empty(&sclp_req_queue)) {
453 req = list_entry(sclp_req_queue.next, struct sclp_req, list);
454 rc = __sclp_start_request(req);
458 if (req->start_count > 1) {
459 /* Cannot abort already submitted request - could still
460 * be active at the SCLP */
461 __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ,
462 sclp_request_timeout_normal);
465 /* Post-processing for aborted request */
466 list_del(&req->list);
468 /* RQAB: Request aborted (a=sccb, b=summary) */
469 sclp_trace_req(2, "RQAB", req, true);
472 spin_unlock_irqrestore(&sclp_lock, flags);
473 req->callback(req, req->callback_data);
474 spin_lock_irqsave(&sclp_lock, flags);
477 spin_unlock_irqrestore(&sclp_lock, flags);
480 static int __sclp_can_add_request(struct sclp_req *req)
482 if (req == &sclp_init_req)
484 if (sclp_init_state != sclp_init_state_initialized)
486 if (sclp_activation_state != sclp_activation_state_active)
491 /* Queue a new request. Return zero on success, non-zero otherwise. */
493 sclp_add_request(struct sclp_req *req)
498 spin_lock_irqsave(&sclp_lock, flags);
499 if (!__sclp_can_add_request(req)) {
500 spin_unlock_irqrestore(&sclp_lock, flags);
504 /* RQAD: Request was added (a=sccb, b=caller) */
505 sclp_trace(2, "RQAD", __pa(req->sccb), _RET_IP_, false);
507 req->status = SCLP_REQ_QUEUED;
508 req->start_count = 0;
509 list_add_tail(&req->list, &sclp_req_queue);
511 if (req->queue_timeout) {
512 req->queue_expires = jiffies + req->queue_timeout * HZ;
513 if (!timer_pending(&sclp_queue_timer) ||
514 time_after(sclp_queue_timer.expires, req->queue_expires))
515 mod_timer(&sclp_queue_timer, req->queue_expires);
517 req->queue_expires = 0;
518 /* Start if request is first in list */
519 if (sclp_running_state == sclp_running_state_idle &&
520 req->list.prev == &sclp_req_queue) {
521 rc = __sclp_start_request(req);
523 list_del(&req->list);
525 spin_unlock_irqrestore(&sclp_lock, flags);
529 EXPORT_SYMBOL(sclp_add_request);
531 /* Dispatch events found in request buffer to registered listeners. Return 0
532 * if all events were dispatched, non-zero otherwise. */
534 sclp_dispatch_evbufs(struct sccb_header *sccb)
537 struct evbuf_header *evbuf;
539 struct sclp_register *reg;
543 spin_lock_irqsave(&sclp_lock, flags);
545 for (offset = sizeof(struct sccb_header); offset < sccb->length;
546 offset += evbuf->length) {
547 evbuf = (struct evbuf_header *) ((addr_t) sccb + offset);
548 /* Check for malformed hardware response */
549 if (evbuf->length == 0)
551 /* Search for event handler */
553 list_for_each(l, &sclp_reg_list) {
554 reg = list_entry(l, struct sclp_register, list);
555 if (reg->receive_mask & SCLP_EVTYP_MASK(evbuf->type))
561 /* EVNT: Event callback (b=receiver) */
562 sclp_trace_evbuf(2, "EVNT", 0, reg ? (u64)reg->receiver_fn : 0,
565 if (reg && reg->receiver_fn) {
566 spin_unlock_irqrestore(&sclp_lock, flags);
567 reg->receiver_fn(evbuf);
568 spin_lock_irqsave(&sclp_lock, flags);
569 } else if (reg == NULL)
572 spin_unlock_irqrestore(&sclp_lock, flags);
576 /* Read event data request callback. */
578 sclp_read_cb(struct sclp_req *req, void *data)
581 struct sccb_header *sccb;
583 sccb = (struct sccb_header *) req->sccb;
584 if (req->status == SCLP_REQ_DONE && (sccb->response_code == 0x20 ||
585 sccb->response_code == 0x220))
586 sclp_dispatch_evbufs(sccb);
587 spin_lock_irqsave(&sclp_lock, flags);
588 sclp_reading_state = sclp_reading_state_idle;
589 spin_unlock_irqrestore(&sclp_lock, flags);
592 /* Prepare read event data request. Called while sclp_lock is locked. */
593 static void __sclp_make_read_req(void)
595 struct sccb_header *sccb;
597 sccb = (struct sccb_header *) sclp_read_sccb;
599 memset(&sclp_read_req, 0, sizeof(struct sclp_req));
600 sclp_read_req.command = SCLP_CMDW_READ_EVENT_DATA;
601 sclp_read_req.status = SCLP_REQ_QUEUED;
602 sclp_read_req.start_count = 0;
603 sclp_read_req.callback = sclp_read_cb;
604 sclp_read_req.sccb = sccb;
605 sccb->length = PAGE_SIZE;
606 sccb->function_code = 0;
607 sccb->control_mask[2] = 0x80;
610 /* Search request list for request with matching sccb. Return request if found,
611 * NULL otherwise. Called while sclp_lock is locked. */
612 static inline struct sclp_req *
613 __sclp_find_req(u32 sccb)
616 struct sclp_req *req;
618 list_for_each(l, &sclp_req_queue) {
619 req = list_entry(l, struct sclp_req, list);
620 if (sccb == __pa(req->sccb))
626 static bool ok_response(u32 sccb_int, sclp_cmdw_t cmd)
628 struct sccb_header *sccb = (struct sccb_header *)__va(sccb_int);
629 struct evbuf_header *evbuf;
635 /* Check SCCB response. */
636 response = sccb->response_code & 0xff;
637 if (response != 0x10 && response != 0x20)
640 /* Check event-processed flag on outgoing events. */
641 if (cmd == SCLP_CMDW_WRITE_EVENT_DATA) {
642 evbuf = (struct evbuf_header *)(sccb + 1);
643 if (!(evbuf->flags & 0x80))
650 /* Handler for external interruption. Perform request post-processing.
651 * Prepare read event data request if necessary. Start processing of next
652 * request on queue. */
653 static void sclp_interrupt_handler(struct ext_code ext_code,
654 unsigned int param32, unsigned long param64)
656 struct sclp_req *req;
660 inc_irq_stat(IRQEXT_SCP);
661 spin_lock(&sclp_lock);
662 finished_sccb = param32 & 0xfffffff8;
663 evbuf_pending = param32 & 0x3;
665 /* INT: Interrupt received (a=intparm, b=cmd) */
666 sclp_trace_sccb(0, "INT", param32, active_cmd, active_cmd,
667 (struct sccb_header *)__va(finished_sccb),
668 !ok_response(finished_sccb, active_cmd));
671 del_timer(&sclp_request_timer);
672 sclp_running_state = sclp_running_state_reset_pending;
673 req = __sclp_find_req(finished_sccb);
675 /* Request post-processing */
676 list_del(&req->list);
677 req->status = SCLP_REQ_DONE;
679 /* RQOK: Request success (a=sccb, b=summary) */
680 sclp_trace_req(2, "RQOK", req, false);
683 spin_unlock(&sclp_lock);
684 req->callback(req, req->callback_data);
685 spin_lock(&sclp_lock);
688 /* UNEX: Unexpected SCCB completion (a=sccb address) */
689 sclp_trace(0, "UNEX", finished_sccb, 0, true);
691 sclp_running_state = sclp_running_state_idle;
695 sclp_activation_state == sclp_activation_state_active)
696 __sclp_queue_read_req();
697 spin_unlock(&sclp_lock);
698 sclp_process_queue();
701 /* Convert interval in jiffies to TOD ticks. */
703 sclp_tod_from_jiffies(unsigned long jiffies)
705 return (u64) (jiffies / HZ) << 32;
708 /* Wait until a currently running request finished. Note: while this function
709 * is running, no timers are served on the calling CPU. */
713 unsigned long long old_tick;
715 unsigned long cr0, cr0_sync;
716 static u64 sync_count;
720 /* SYN1: Synchronous wait start (a=runstate, b=sync count) */
721 sclp_trace(4, "SYN1", sclp_running_state, ++sync_count, false);
723 /* We'll be disabling timer interrupts, so we need a custom timeout
726 if (timer_pending(&sclp_request_timer)) {
727 /* Get timeout TOD value */
728 timeout = get_tod_clock_fast() +
729 sclp_tod_from_jiffies(sclp_request_timer.expires -
732 local_irq_save(flags);
733 /* Prevent bottom half from executing once we force interrupts open */
734 irq_context = in_interrupt();
737 /* Enable service-signal interruption, disable timer interrupts */
738 old_tick = local_tick_disable();
740 __ctl_store(cr0, 0, 0);
741 cr0_sync = cr0 & ~CR0_IRQ_SUBCLASS_MASK;
742 cr0_sync |= 1UL << (63 - 54);
743 __ctl_load(cr0_sync, 0, 0);
744 __arch_local_irq_stosm(0x01);
745 /* Loop until driver state indicates finished request */
746 while (sclp_running_state != sclp_running_state_idle) {
747 /* Check for expired request timer */
748 if (get_tod_clock_fast() > timeout && del_timer(&sclp_request_timer))
749 sclp_request_timer.function(&sclp_request_timer);
753 __ctl_load(cr0, 0, 0);
756 local_tick_enable(old_tick);
757 local_irq_restore(flags);
759 /* SYN2: Synchronous wait end (a=runstate, b=sync_count) */
760 sclp_trace(4, "SYN2", sclp_running_state, sync_count, false);
762 EXPORT_SYMBOL(sclp_sync_wait);
764 /* Dispatch changes in send and receive mask to registered listeners. */
766 sclp_dispatch_state_change(void)
769 struct sclp_register *reg;
771 sccb_mask_t receive_mask;
772 sccb_mask_t send_mask;
775 spin_lock_irqsave(&sclp_lock, flags);
777 list_for_each(l, &sclp_reg_list) {
778 reg = list_entry(l, struct sclp_register, list);
779 receive_mask = reg->send_mask & sclp_receive_mask;
780 send_mask = reg->receive_mask & sclp_send_mask;
781 if (reg->sclp_receive_mask != receive_mask ||
782 reg->sclp_send_mask != send_mask) {
783 reg->sclp_receive_mask = receive_mask;
784 reg->sclp_send_mask = send_mask;
789 spin_unlock_irqrestore(&sclp_lock, flags);
790 if (reg && reg->state_change_fn) {
791 /* STCG: State-change callback (b=callback) */
792 sclp_trace(2, "STCG", 0, (u64)reg->state_change_fn,
795 reg->state_change_fn(reg);
800 struct sclp_statechangebuf {
801 struct evbuf_header header;
802 u8 validity_sclp_active_facility_mask : 1;
803 u8 validity_sclp_receive_mask : 1;
804 u8 validity_sclp_send_mask : 1;
805 u8 validity_read_data_function_mask : 1;
808 u64 sclp_active_facility_mask;
809 u8 masks[2 * 1021 + 4]; /* variable length */
811 * u8 sclp_receive_mask[mask_length];
812 * u8 sclp_send_mask[mask_length];
813 * u32 read_data_function_mask;
815 } __attribute__((packed));
818 /* State change event callback. Inform listeners of changes. */
820 sclp_state_change_cb(struct evbuf_header *evbuf)
823 struct sclp_statechangebuf *scbuf;
825 BUILD_BUG_ON(sizeof(struct sclp_statechangebuf) > PAGE_SIZE);
827 scbuf = (struct sclp_statechangebuf *) evbuf;
828 spin_lock_irqsave(&sclp_lock, flags);
829 if (scbuf->validity_sclp_receive_mask)
830 sclp_receive_mask = sccb_get_recv_mask(scbuf);
831 if (scbuf->validity_sclp_send_mask)
832 sclp_send_mask = sccb_get_send_mask(scbuf);
833 spin_unlock_irqrestore(&sclp_lock, flags);
834 if (scbuf->validity_sclp_active_facility_mask)
835 sclp.facilities = scbuf->sclp_active_facility_mask;
836 sclp_dispatch_state_change();
839 static struct sclp_register sclp_state_change_event = {
840 .receive_mask = EVTYP_STATECHANGE_MASK,
841 .receiver_fn = sclp_state_change_cb
844 /* Calculate receive and send mask of currently registered listeners.
845 * Called while sclp_lock is locked. */
847 __sclp_get_mask(sccb_mask_t *receive_mask, sccb_mask_t *send_mask)
850 struct sclp_register *t;
854 list_for_each(l, &sclp_reg_list) {
855 t = list_entry(l, struct sclp_register, list);
856 *receive_mask |= t->receive_mask;
857 *send_mask |= t->send_mask;
861 /* Register event listener. Return 0 on success, non-zero otherwise. */
863 sclp_register(struct sclp_register *reg)
866 sccb_mask_t receive_mask;
867 sccb_mask_t send_mask;
870 /* REG: Event listener registered (b=caller) */
871 sclp_trace_register(2, "REG", 0, _RET_IP_, reg);
876 spin_lock_irqsave(&sclp_lock, flags);
877 /* Check event mask for collisions */
878 __sclp_get_mask(&receive_mask, &send_mask);
879 if (reg->receive_mask & receive_mask || reg->send_mask & send_mask) {
880 spin_unlock_irqrestore(&sclp_lock, flags);
883 /* Trigger initial state change callback */
884 reg->sclp_receive_mask = 0;
885 reg->sclp_send_mask = 0;
886 list_add(®->list, &sclp_reg_list);
887 spin_unlock_irqrestore(&sclp_lock, flags);
888 rc = sclp_init_mask(1);
890 spin_lock_irqsave(&sclp_lock, flags);
891 list_del(®->list);
892 spin_unlock_irqrestore(&sclp_lock, flags);
897 EXPORT_SYMBOL(sclp_register);
899 /* Unregister event listener. */
901 sclp_unregister(struct sclp_register *reg)
905 /* UREG: Event listener unregistered (b=caller) */
906 sclp_trace_register(2, "UREG", 0, _RET_IP_, reg);
908 spin_lock_irqsave(&sclp_lock, flags);
909 list_del(®->list);
910 spin_unlock_irqrestore(&sclp_lock, flags);
914 EXPORT_SYMBOL(sclp_unregister);
916 /* Remove event buffers which are marked processed. Return the number of
917 * remaining event buffers. */
919 sclp_remove_processed(struct sccb_header *sccb)
921 struct evbuf_header *evbuf;
925 evbuf = (struct evbuf_header *) (sccb + 1);
927 remaining = sccb->length - sizeof(struct sccb_header);
928 while (remaining > 0) {
929 remaining -= evbuf->length;
930 if (evbuf->flags & 0x80) {
931 sccb->length -= evbuf->length;
932 memcpy(evbuf, (void *) ((addr_t) evbuf + evbuf->length),
936 evbuf = (struct evbuf_header *)
937 ((addr_t) evbuf + evbuf->length);
943 EXPORT_SYMBOL(sclp_remove_processed);
945 /* Prepare init mask request. Called while sclp_lock is locked. */
947 __sclp_make_init_req(sccb_mask_t receive_mask, sccb_mask_t send_mask)
949 struct init_sccb *sccb = sclp_init_sccb;
952 memset(&sclp_init_req, 0, sizeof(struct sclp_req));
953 sclp_init_req.command = SCLP_CMDW_WRITE_EVENT_MASK;
954 sclp_init_req.status = SCLP_REQ_FILLED;
955 sclp_init_req.start_count = 0;
956 sclp_init_req.callback = NULL;
957 sclp_init_req.callback_data = NULL;
958 sclp_init_req.sccb = sccb;
959 sccb->header.length = sizeof(*sccb);
960 if (sclp_mask_compat_mode)
961 sccb->mask_length = SCLP_MASK_SIZE_COMPAT;
963 sccb->mask_length = sizeof(sccb_mask_t);
964 sccb_set_recv_mask(sccb, receive_mask);
965 sccb_set_send_mask(sccb, send_mask);
966 sccb_set_sclp_recv_mask(sccb, 0);
967 sccb_set_sclp_send_mask(sccb, 0);
970 /* Start init mask request. If calculate is non-zero, calculate the mask as
971 * requested by registered listeners. Use zero mask otherwise. Return 0 on
972 * success, non-zero otherwise. */
974 sclp_init_mask(int calculate)
977 struct init_sccb *sccb = sclp_init_sccb;
978 sccb_mask_t receive_mask;
979 sccb_mask_t send_mask;
984 spin_lock_irqsave(&sclp_lock, flags);
985 /* Check if interface is in appropriate state */
986 if (sclp_mask_state != sclp_mask_state_idle) {
987 spin_unlock_irqrestore(&sclp_lock, flags);
990 if (sclp_activation_state == sclp_activation_state_inactive) {
991 spin_unlock_irqrestore(&sclp_lock, flags);
994 sclp_mask_state = sclp_mask_state_initializing;
997 __sclp_get_mask(&receive_mask, &send_mask);
1003 for (retry = 0; retry <= SCLP_MASK_RETRY; retry++) {
1004 /* Prepare request */
1005 __sclp_make_init_req(receive_mask, send_mask);
1006 spin_unlock_irqrestore(&sclp_lock, flags);
1007 if (sclp_add_request(&sclp_init_req)) {
1008 /* Try again later */
1009 wait = jiffies + SCLP_BUSY_INTERVAL * HZ;
1010 while (time_before(jiffies, wait))
1012 spin_lock_irqsave(&sclp_lock, flags);
1015 while (sclp_init_req.status != SCLP_REQ_DONE &&
1016 sclp_init_req.status != SCLP_REQ_FAILED)
1018 spin_lock_irqsave(&sclp_lock, flags);
1019 if (sclp_init_req.status == SCLP_REQ_DONE &&
1020 sccb->header.response_code == 0x20) {
1021 /* Successful request */
1023 sclp_receive_mask = sccb_get_sclp_recv_mask(sccb);
1024 sclp_send_mask = sccb_get_sclp_send_mask(sccb);
1026 sclp_receive_mask = 0;
1029 spin_unlock_irqrestore(&sclp_lock, flags);
1030 sclp_dispatch_state_change();
1031 spin_lock_irqsave(&sclp_lock, flags);
1036 sclp_mask_state = sclp_mask_state_idle;
1037 spin_unlock_irqrestore(&sclp_lock, flags);
1041 /* Deactivate SCLP interface. On success, new requests will be rejected,
1042 * events will no longer be dispatched. Return 0 on success, non-zero
1045 sclp_deactivate(void)
1047 unsigned long flags;
1050 spin_lock_irqsave(&sclp_lock, flags);
1051 /* Deactivate can only be called when active */
1052 if (sclp_activation_state != sclp_activation_state_active) {
1053 spin_unlock_irqrestore(&sclp_lock, flags);
1056 sclp_activation_state = sclp_activation_state_deactivating;
1057 spin_unlock_irqrestore(&sclp_lock, flags);
1058 rc = sclp_init_mask(0);
1059 spin_lock_irqsave(&sclp_lock, flags);
1061 sclp_activation_state = sclp_activation_state_inactive;
1063 sclp_activation_state = sclp_activation_state_active;
1064 spin_unlock_irqrestore(&sclp_lock, flags);
1068 EXPORT_SYMBOL(sclp_deactivate);
1070 /* Reactivate SCLP interface after sclp_deactivate. On success, new
1071 * requests will be accepted, events will be dispatched again. Return 0 on
1072 * success, non-zero otherwise. */
1074 sclp_reactivate(void)
1076 unsigned long flags;
1079 spin_lock_irqsave(&sclp_lock, flags);
1080 /* Reactivate can only be called when inactive */
1081 if (sclp_activation_state != sclp_activation_state_inactive) {
1082 spin_unlock_irqrestore(&sclp_lock, flags);
1085 sclp_activation_state = sclp_activation_state_activating;
1086 spin_unlock_irqrestore(&sclp_lock, flags);
1087 rc = sclp_init_mask(1);
1088 spin_lock_irqsave(&sclp_lock, flags);
1090 sclp_activation_state = sclp_activation_state_active;
1092 sclp_activation_state = sclp_activation_state_inactive;
1093 spin_unlock_irqrestore(&sclp_lock, flags);
1097 EXPORT_SYMBOL(sclp_reactivate);
1099 /* Handler for external interruption used during initialization. Modify
1100 * request state to done. */
1101 static void sclp_check_handler(struct ext_code ext_code,
1102 unsigned int param32, unsigned long param64)
1106 inc_irq_stat(IRQEXT_SCP);
1107 finished_sccb = param32 & 0xfffffff8;
1108 /* Is this the interrupt we are waiting for? */
1109 if (finished_sccb == 0)
1111 if (finished_sccb != __pa(sclp_init_sccb))
1112 panic("sclp: unsolicited interrupt for buffer at 0x%x\n",
1114 spin_lock(&sclp_lock);
1115 if (sclp_running_state == sclp_running_state_running) {
1116 sclp_init_req.status = SCLP_REQ_DONE;
1117 sclp_running_state = sclp_running_state_idle;
1119 spin_unlock(&sclp_lock);
1122 /* Initial init mask request timed out. Modify request state to failed. */
1124 sclp_check_timeout(struct timer_list *unused)
1126 unsigned long flags;
1128 spin_lock_irqsave(&sclp_lock, flags);
1129 if (sclp_running_state == sclp_running_state_running) {
1130 sclp_init_req.status = SCLP_REQ_FAILED;
1131 sclp_running_state = sclp_running_state_idle;
1133 spin_unlock_irqrestore(&sclp_lock, flags);
1136 /* Perform a check of the SCLP interface. Return zero if the interface is
1137 * available and there are no pending requests from a previous instance.
1138 * Return non-zero otherwise. */
1140 sclp_check_interface(void)
1142 struct init_sccb *sccb;
1143 unsigned long flags;
1147 spin_lock_irqsave(&sclp_lock, flags);
1148 /* Prepare init mask command */
1149 rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler);
1151 spin_unlock_irqrestore(&sclp_lock, flags);
1154 for (retry = 0; retry <= SCLP_INIT_RETRY; retry++) {
1155 __sclp_make_init_req(0, 0);
1156 sccb = (struct init_sccb *) sclp_init_req.sccb;
1157 rc = sclp_service_call_trace(sclp_init_req.command, sccb);
1160 sclp_init_req.status = SCLP_REQ_RUNNING;
1161 sclp_running_state = sclp_running_state_running;
1162 __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ,
1163 sclp_check_timeout);
1164 spin_unlock_irqrestore(&sclp_lock, flags);
1165 /* Enable service-signal interruption - needs to happen
1166 * with IRQs enabled. */
1167 irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
1168 /* Wait for signal from interrupt or timeout */
1170 /* Disable service-signal interruption - needs to happen
1171 * with IRQs enabled. */
1172 irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL);
1173 spin_lock_irqsave(&sclp_lock, flags);
1174 del_timer(&sclp_request_timer);
1176 if (sclp_init_req.status == SCLP_REQ_DONE) {
1177 if (sccb->header.response_code == 0x20) {
1180 } else if (sccb->header.response_code == 0x74f0) {
1181 if (!sclp_mask_compat_mode) {
1182 sclp_mask_compat_mode = true;
1188 unregister_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler);
1189 spin_unlock_irqrestore(&sclp_lock, flags);
1193 /* Reboot event handler. Reset send and receive mask to prevent pending SCLP
1194 * events from interfering with rebooted system. */
1196 sclp_reboot_event(struct notifier_block *this, unsigned long event, void *ptr)
1202 static struct notifier_block sclp_reboot_notifier = {
1203 .notifier_call = sclp_reboot_event
1206 static ssize_t con_pages_show(struct device_driver *dev, char *buf)
1208 return sprintf(buf, "%i\n", sclp_console_pages);
1211 static DRIVER_ATTR_RO(con_pages);
1213 static ssize_t con_drop_show(struct device_driver *dev, char *buf)
1215 return sprintf(buf, "%i\n", sclp_console_drop);
1218 static DRIVER_ATTR_RO(con_drop);
1220 static ssize_t con_full_show(struct device_driver *dev, char *buf)
1222 return sprintf(buf, "%lu\n", sclp_console_full);
1225 static DRIVER_ATTR_RO(con_full);
1227 static struct attribute *sclp_drv_attrs[] = {
1228 &driver_attr_con_pages.attr,
1229 &driver_attr_con_drop.attr,
1230 &driver_attr_con_full.attr,
1233 static struct attribute_group sclp_drv_attr_group = {
1234 .attrs = sclp_drv_attrs,
1236 static const struct attribute_group *sclp_drv_attr_groups[] = {
1237 &sclp_drv_attr_group,
1241 static struct platform_driver sclp_pdrv = {
1244 .groups = sclp_drv_attr_groups,
1248 /* Initialize SCLP driver. Return zero if driver is operational, non-zero
1253 unsigned long flags;
1256 spin_lock_irqsave(&sclp_lock, flags);
1257 /* Check for previous or running initialization */
1258 if (sclp_init_state != sclp_init_state_uninitialized)
1260 sclp_init_state = sclp_init_state_initializing;
1261 sclp_read_sccb = (void *) __get_free_page(GFP_ATOMIC | GFP_DMA);
1262 sclp_init_sccb = (void *) __get_free_page(GFP_ATOMIC | GFP_DMA);
1263 BUG_ON(!sclp_read_sccb || !sclp_init_sccb);
1264 /* Set up variables */
1265 list_add(&sclp_state_change_event.list, &sclp_reg_list);
1266 timer_setup(&sclp_request_timer, NULL, 0);
1267 timer_setup(&sclp_queue_timer, sclp_req_queue_timeout, 0);
1268 /* Check interface */
1269 spin_unlock_irqrestore(&sclp_lock, flags);
1270 rc = sclp_check_interface();
1271 spin_lock_irqsave(&sclp_lock, flags);
1273 goto fail_init_state_uninitialized;
1274 /* Register reboot handler */
1275 rc = register_reboot_notifier(&sclp_reboot_notifier);
1277 goto fail_init_state_uninitialized;
1278 /* Register interrupt handler */
1279 rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_interrupt_handler);
1281 goto fail_unregister_reboot_notifier;
1282 sclp_init_state = sclp_init_state_initialized;
1283 spin_unlock_irqrestore(&sclp_lock, flags);
1284 /* Enable service-signal external interruption - needs to happen with
1286 irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
1290 fail_unregister_reboot_notifier:
1291 unregister_reboot_notifier(&sclp_reboot_notifier);
1292 fail_init_state_uninitialized:
1293 sclp_init_state = sclp_init_state_uninitialized;
1294 free_page((unsigned long) sclp_read_sccb);
1295 free_page((unsigned long) sclp_init_sccb);
1297 spin_unlock_irqrestore(&sclp_lock, flags);
1301 static __init int sclp_initcall(void)
1305 rc = platform_driver_register(&sclp_pdrv);
1312 arch_initcall(sclp_initcall);