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1/*
2 * SN Platform GRU Driver
3 *
4 * KERNEL SERVICES THAT USE THE GRU
5 *
6 * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22
23#include <linux/kernel.h>
24#include <linux/errno.h>
25#include <linux/slab.h>
26#include <linux/mm.h>
27#include <linux/spinlock.h>
28#include <linux/device.h>
29#include <linux/miscdevice.h>
30#include <linux/proc_fs.h>
31#include <linux/interrupt.h>
32#include <linux/uaccess.h>
33#include <linux/delay.h>
34#include <asm/io_apic.h>
35#include "gru.h"
36#include "grulib.h"
37#include "grutables.h"
38#include "grukservices.h"
39#include "gru_instructions.h"
40#include <asm/uv/uv_hub.h>
41
42/*
43 * Kernel GRU Usage
44 *
45 * The following is an interim algorithm for management of kernel GRU
46 * resources. This will likely be replaced when we better understand the
47 * kernel/user requirements.
48 *
49 * Blade percpu resources reserved for kernel use. These resources are
50 * reserved whenever the the kernel context for the blade is loaded. Note
51 * that the kernel context is not guaranteed to be always available. It is
52 * loaded on demand & can be stolen by a user if the user demand exceeds the
53 * kernel demand. The kernel can always reload the kernel context but
54 * a SLEEP may be required!!!.
55 *
56 * Async Overview:
57 *
58 * Each blade has one "kernel context" that owns GRU kernel resources
59 * located on the blade. Kernel drivers use GRU resources in this context
60 * for sending messages, zeroing memory, etc.
61 *
62 * The kernel context is dynamically loaded on demand. If it is not in
63 * use by the kernel, the kernel context can be unloaded & given to a user.
64 * The kernel context will be reloaded when needed. This may require that
65 * a context be stolen from a user.
66 * NOTE: frequent unloading/reloading of the kernel context is
67 * expensive. We are depending on batch schedulers, cpusets, sane
68 * drivers or some other mechanism to prevent the need for frequent
69 * stealing/reloading.
70 *
71 * The kernel context consists of two parts:
72 * - 1 CB & a few DSRs that are reserved for each cpu on the blade.
73 * Each cpu has it's own private resources & does not share them
74 * with other cpus. These resources are used serially, ie,
75 * locked, used & unlocked on each call to a function in
76 * grukservices.
77 * (Now that we have dynamic loading of kernel contexts, I
78 * may rethink this & allow sharing between cpus....)
79 *
80 * - Additional resources can be reserved long term & used directly
81 * by UV drivers located in the kernel. Drivers using these GRU
82 * resources can use asynchronous GRU instructions that send
83 * interrupts on completion.
84 * - these resources must be explicitly locked/unlocked
85 * - locked resources prevent (obviously) the kernel
86 * context from being unloaded.
87 * - drivers using these resource directly issue their own
88 * GRU instruction and must wait/check completion.
89 *
90 * When these resources are reserved, the caller can optionally
91 * associate a wait_queue with the resources and use asynchronous
92 * GRU instructions. When an async GRU instruction completes, the
93 * driver will do a wakeup on the event.
94 *
95 */
96
97
98#define ASYNC_HAN_TO_BID(h) ((h) - 1)
99#define ASYNC_BID_TO_HAN(b) ((b) + 1)
100#define ASYNC_HAN_TO_BS(h) gru_base[ASYNC_HAN_TO_BID(h)]
101
102#define GRU_NUM_KERNEL_CBR 1
103#define GRU_NUM_KERNEL_DSR_BYTES 256
104#define GRU_NUM_KERNEL_DSR_CL (GRU_NUM_KERNEL_DSR_BYTES / \
105 GRU_CACHE_LINE_BYTES)
106
107/* GRU instruction attributes for all instructions */
108#define IMA IMA_CB_DELAY
109
110/* GRU cacheline size is always 64 bytes - even on arches with 128 byte lines */
111#define __gru_cacheline_aligned__ \
112 __attribute__((__aligned__(GRU_CACHE_LINE_BYTES)))
113
114#define MAGIC 0x1234567887654321UL
115
116/* Default retry count for GRU errors on kernel instructions */
117#define EXCEPTION_RETRY_LIMIT 3
118
119/* Status of message queue sections */
120#define MQS_EMPTY 0
121#define MQS_FULL 1
122#define MQS_NOOP 2
123
124/*----------------- RESOURCE MANAGEMENT -------------------------------------*/
125/* optimized for x86_64 */
126struct message_queue {
127 union gru_mesqhead head __gru_cacheline_aligned__; /* CL 0 */
128 int qlines; /* DW 1 */
129 long hstatus[2];
130 void *next __gru_cacheline_aligned__;/* CL 1 */
131 void *limit;
132 void *start;
133 void *start2;
134 char data ____cacheline_aligned; /* CL 2 */
135};
136
137/* First word in every message - used by mesq interface */
138struct message_header {
139 char present;
140 char present2;
141 char lines;
142 char fill;
143};
144
145#define HSTATUS(mq, h) ((mq) + offsetof(struct message_queue, hstatus[h]))
146
147/*
148 * Reload the blade's kernel context into a GRU chiplet. Called holding
149 * the bs_kgts_sema for READ. Will steal user contexts if necessary.
150 */
151static void gru_load_kernel_context(struct gru_blade_state *bs, int blade_id)
152{
153 struct gru_state *gru;
154 struct gru_thread_state *kgts;
155 void *vaddr;
156 int ctxnum, ncpus;
157
158 up_read(&bs->bs_kgts_sema);
159 down_write(&bs->bs_kgts_sema);
160
161 if (!bs->bs_kgts) {
162 bs->bs_kgts = gru_alloc_gts(NULL, 0, 0, 0, 0, 0);
163 bs->bs_kgts->ts_user_blade_id = blade_id;
164 }
165 kgts = bs->bs_kgts;
166
167 if (!kgts->ts_gru) {
168 STAT(load_kernel_context);
169 ncpus = uv_blade_nr_possible_cpus(blade_id);
170 kgts->ts_cbr_au_count = GRU_CB_COUNT_TO_AU(
171 GRU_NUM_KERNEL_CBR * ncpus + bs->bs_async_cbrs);
172 kgts->ts_dsr_au_count = GRU_DS_BYTES_TO_AU(
173 GRU_NUM_KERNEL_DSR_BYTES * ncpus +
174 bs->bs_async_dsr_bytes);
175 while (!gru_assign_gru_context(kgts)) {
176 msleep(1);
177 gru_steal_context(kgts);
178 }
179 gru_load_context(kgts);
180 gru = bs->bs_kgts->ts_gru;
181 vaddr = gru->gs_gru_base_vaddr;
182 ctxnum = kgts->ts_ctxnum;
183 bs->kernel_cb = get_gseg_base_address_cb(vaddr, ctxnum, 0);
184 bs->kernel_dsr = get_gseg_base_address_ds(vaddr, ctxnum, 0);
185 }
186 downgrade_write(&bs->bs_kgts_sema);
187}
188
189/*
190 * Free all kernel contexts that are not currently in use.
191 * Returns 0 if all freed, else number of inuse context.
192 */
193static int gru_free_kernel_contexts(void)
194{
195 struct gru_blade_state *bs;
196 struct gru_thread_state *kgts;
197 int bid, ret = 0;
198
199 for (bid = 0; bid < GRU_MAX_BLADES; bid++) {
200 bs = gru_base[bid];
201 if (!bs)
202 continue;
203
204 /* Ignore busy contexts. Don't want to block here. */
205 if (down_write_trylock(&bs->bs_kgts_sema)) {
206 kgts = bs->bs_kgts;
207 if (kgts && kgts->ts_gru)
208 gru_unload_context(kgts, 0);
209 bs->bs_kgts = NULL;
210 up_write(&bs->bs_kgts_sema);
211 kfree(kgts);
212 } else {
213 ret++;
214 }
215 }
216 return ret;
217}
218
219/*
220 * Lock & load the kernel context for the specified blade.
221 */
222static struct gru_blade_state *gru_lock_kernel_context(int blade_id)
223{
224 struct gru_blade_state *bs;
225 int bid;
226
227 STAT(lock_kernel_context);
228again:
229 bid = blade_id < 0 ? uv_numa_blade_id() : blade_id;
230 bs = gru_base[bid];
231
232 /* Handle the case where migration occurred while waiting for the sema */
233 down_read(&bs->bs_kgts_sema);
234 if (blade_id < 0 && bid != uv_numa_blade_id()) {
235 up_read(&bs->bs_kgts_sema);
236 goto again;
237 }
238 if (!bs->bs_kgts || !bs->bs_kgts->ts_gru)
239 gru_load_kernel_context(bs, bid);
240 return bs;
241
242}
243
244/*
245 * Unlock the kernel context for the specified blade. Context is not
246 * unloaded but may be stolen before next use.
247 */
248static void gru_unlock_kernel_context(int blade_id)
249{
250 struct gru_blade_state *bs;
251
252 bs = gru_base[blade_id];
253 up_read(&bs->bs_kgts_sema);
254 STAT(unlock_kernel_context);
255}
256
257/*
258 * Reserve & get pointers to the DSR/CBRs reserved for the current cpu.
259 * - returns with preemption disabled
260 */
261static int gru_get_cpu_resources(int dsr_bytes, void **cb, void **dsr)
262{
263 struct gru_blade_state *bs;
264 int lcpu;
265
266 BUG_ON(dsr_bytes > GRU_NUM_KERNEL_DSR_BYTES);
267 preempt_disable();
268 bs = gru_lock_kernel_context(-1);
269 lcpu = uv_blade_processor_id();
270 *cb = bs->kernel_cb + lcpu * GRU_HANDLE_STRIDE;
271 *dsr = bs->kernel_dsr + lcpu * GRU_NUM_KERNEL_DSR_BYTES;
272 return 0;
273}
274
275/*
276 * Free the current cpus reserved DSR/CBR resources.
277 */
278static void gru_free_cpu_resources(void *cb, void *dsr)
279{
280 gru_unlock_kernel_context(uv_numa_blade_id());
281 preempt_enable();
282}
283
284/*
285 * Reserve GRU resources to be used asynchronously.
286 * Note: currently supports only 1 reservation per blade.
287 *
288 * input:
289 * blade_id - blade on which resources should be reserved
290 * cbrs - number of CBRs
291 * dsr_bytes - number of DSR bytes needed
292 * output:
293 * handle to identify resource
294 * (0 = async resources already reserved)
295 */
296unsigned long gru_reserve_async_resources(int blade_id, int cbrs, int dsr_bytes,
297 struct completion *cmp)
298{
299 struct gru_blade_state *bs;
300 struct gru_thread_state *kgts;
301 int ret = 0;
302
303 bs = gru_base[blade_id];
304
305 down_write(&bs->bs_kgts_sema);
306
307 /* Verify no resources already reserved */
308 if (bs->bs_async_dsr_bytes + bs->bs_async_cbrs)
309 goto done;
310 bs->bs_async_dsr_bytes = dsr_bytes;
311 bs->bs_async_cbrs = cbrs;
312 bs->bs_async_wq = cmp;
313 kgts = bs->bs_kgts;
314
315 /* Resources changed. Unload context if already loaded */
316 if (kgts && kgts->ts_gru)
317 gru_unload_context(kgts, 0);
318 ret = ASYNC_BID_TO_HAN(blade_id);
319
320done:
321 up_write(&bs->bs_kgts_sema);
322 return ret;
323}
324
325/*
326 * Release async resources previously reserved.
327 *
328 * input:
329 * han - handle to identify resources
330 */
331void gru_release_async_resources(unsigned long han)
332{
333 struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
334
335 down_write(&bs->bs_kgts_sema);
336 bs->bs_async_dsr_bytes = 0;
337 bs->bs_async_cbrs = 0;
338 bs->bs_async_wq = NULL;
339 up_write(&bs->bs_kgts_sema);
340}
341
342/*
343 * Wait for async GRU instructions to complete.
344 *
345 * input:
346 * han - handle to identify resources
347 */
348void gru_wait_async_cbr(unsigned long han)
349{
350 struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
351
352 wait_for_completion(bs->bs_async_wq);
353 mb();
354}
355
356/*
357 * Lock previous reserved async GRU resources
358 *
359 * input:
360 * han - handle to identify resources
361 * output:
362 * cb - pointer to first CBR
363 * dsr - pointer to first DSR
364 */
365void gru_lock_async_resource(unsigned long han, void **cb, void **dsr)
366{
367 struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
368 int blade_id = ASYNC_HAN_TO_BID(han);
369 int ncpus;
370
371 gru_lock_kernel_context(blade_id);
372 ncpus = uv_blade_nr_possible_cpus(blade_id);
373 if (cb)
374 *cb = bs->kernel_cb + ncpus * GRU_HANDLE_STRIDE;
375 if (dsr)
376 *dsr = bs->kernel_dsr + ncpus * GRU_NUM_KERNEL_DSR_BYTES;
377}
378
379/*
380 * Unlock previous reserved async GRU resources
381 *
382 * input:
383 * han - handle to identify resources
384 */
385void gru_unlock_async_resource(unsigned long han)
386{
387 int blade_id = ASYNC_HAN_TO_BID(han);
388
389 gru_unlock_kernel_context(blade_id);
390}
391
392/*----------------------------------------------------------------------*/
393int gru_get_cb_exception_detail(void *cb,
394 struct control_block_extended_exc_detail *excdet)
395{
396 struct gru_control_block_extended *cbe;
397 struct gru_thread_state *kgts = NULL;
398 unsigned long off;
399 int cbrnum, bid;
400
401 /*
402 * Locate kgts for cb. This algorithm is SLOW but
403 * this function is rarely called (ie., almost never).
404 * Performance does not matter.
405 */
406 for_each_possible_blade(bid) {
407 if (!gru_base[bid])
408 break;
409 kgts = gru_base[bid]->bs_kgts;
410 if (!kgts || !kgts->ts_gru)
411 continue;
412 off = cb - kgts->ts_gru->gs_gru_base_vaddr;
413 if (off < GRU_SIZE)
414 break;
415 kgts = NULL;
416 }
417 BUG_ON(!kgts);
418 cbrnum = thread_cbr_number(kgts, get_cb_number(cb));
419 cbe = get_cbe(GRUBASE(cb), cbrnum);
420 gru_flush_cache(cbe); /* CBE not coherent */
421 sync_core();
422 excdet->opc = cbe->opccpy;
423 excdet->exopc = cbe->exopccpy;
424 excdet->ecause = cbe->ecause;
425 excdet->exceptdet0 = cbe->idef1upd;
426 excdet->exceptdet1 = cbe->idef3upd;
427 gru_flush_cache(cbe);
428 return 0;
429}
430
431char *gru_get_cb_exception_detail_str(int ret, void *cb,
432 char *buf, int size)
433{
434 struct gru_control_block_status *gen = (void *)cb;
435 struct control_block_extended_exc_detail excdet;
436
437 if (ret > 0 && gen->istatus == CBS_EXCEPTION) {
438 gru_get_cb_exception_detail(cb, &excdet);
439 snprintf(buf, size,
440 "GRU:%d exception: cb %p, opc %d, exopc %d, ecause 0x%x,"
441 "excdet0 0x%lx, excdet1 0x%x", smp_processor_id(),
442 gen, excdet.opc, excdet.exopc, excdet.ecause,
443 excdet.exceptdet0, excdet.exceptdet1);
444 } else {
445 snprintf(buf, size, "No exception");
446 }
447 return buf;
448}
449
450static int gru_wait_idle_or_exception(struct gru_control_block_status *gen)
451{
452 while (gen->istatus >= CBS_ACTIVE) {
453 cpu_relax();
454 barrier();
455 }
456 return gen->istatus;
457}
458
459static int gru_retry_exception(void *cb)
460{
461 struct gru_control_block_status *gen = (void *)cb;
462 struct control_block_extended_exc_detail excdet;
463 int retry = EXCEPTION_RETRY_LIMIT;
464
465 while (1) {
466 if (gru_wait_idle_or_exception(gen) == CBS_IDLE)
467 return CBS_IDLE;
468 if (gru_get_cb_message_queue_substatus(cb))
469 return CBS_EXCEPTION;
470 gru_get_cb_exception_detail(cb, &excdet);
471 if ((excdet.ecause & ~EXCEPTION_RETRY_BITS) ||
472 (excdet.cbrexecstatus & CBR_EXS_ABORT_OCC))
473 break;
474 if (retry-- == 0)
475 break;
476 gen->icmd = 1;
477 gru_flush_cache(gen);
478 }
479 return CBS_EXCEPTION;
480}
481
482int gru_check_status_proc(void *cb)
483{
484 struct gru_control_block_status *gen = (void *)cb;
485 int ret;
486
487 ret = gen->istatus;
488 if (ret == CBS_EXCEPTION)
489 ret = gru_retry_exception(cb);
490 rmb();
491 return ret;
492
493}
494
495int gru_wait_proc(void *cb)
496{
497 struct gru_control_block_status *gen = (void *)cb;
498 int ret;
499
500 ret = gru_wait_idle_or_exception(gen);
501 if (ret == CBS_EXCEPTION)
502 ret = gru_retry_exception(cb);
503 rmb();
504 return ret;
505}
506
507void gru_abort(int ret, void *cb, char *str)
508{
509 char buf[GRU_EXC_STR_SIZE];
510
511 panic("GRU FATAL ERROR: %s - %s\n", str,
512 gru_get_cb_exception_detail_str(ret, cb, buf, sizeof(buf)));
513}
514
515void gru_wait_abort_proc(void *cb)
516{
517 int ret;
518
519 ret = gru_wait_proc(cb);
520 if (ret)
521 gru_abort(ret, cb, "gru_wait_abort");
522}
523
524
525/*------------------------------ MESSAGE QUEUES -----------------------------*/
526
527/* Internal status . These are NOT returned to the user. */
528#define MQIE_AGAIN -1 /* try again */
529
530
531/*
532 * Save/restore the "present" flag that is in the second line of 2-line
533 * messages
534 */
535static inline int get_present2(void *p)
536{
537 struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES;
538 return mhdr->present;
539}
540
541static inline void restore_present2(void *p, int val)
542{
543 struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES;
544 mhdr->present = val;
545}
546
547/*
548 * Create a message queue.
549 * qlines - message queue size in cache lines. Includes 2-line header.
550 */
551int gru_create_message_queue(struct gru_message_queue_desc *mqd,
552 void *p, unsigned int bytes, int nasid, int vector, int apicid)
553{
554 struct message_queue *mq = p;
555 unsigned int qlines;
556
557 qlines = bytes / GRU_CACHE_LINE_BYTES - 2;
558 memset(mq, 0, bytes);
559 mq->start = &mq->data;
560 mq->start2 = &mq->data + (qlines / 2 - 1) * GRU_CACHE_LINE_BYTES;
561 mq->next = &mq->data;
562 mq->limit = &mq->data + (qlines - 2) * GRU_CACHE_LINE_BYTES;
563 mq->qlines = qlines;
564 mq->hstatus[0] = 0;
565 mq->hstatus[1] = 1;
566 mq->head = gru_mesq_head(2, qlines / 2 + 1);
567 mqd->mq = mq;
568 mqd->mq_gpa = uv_gpa(mq);
569 mqd->qlines = qlines;
570 mqd->interrupt_pnode = nasid >> 1;
571 mqd->interrupt_vector = vector;
572 mqd->interrupt_apicid = apicid;
573 return 0;
574}
575EXPORT_SYMBOL_GPL(gru_create_message_queue);
576
577/*
578 * Send a NOOP message to a message queue
579 * Returns:
580 * 0 - if queue is full after the send. This is the normal case
581 * but various races can change this.
582 * -1 - if mesq sent successfully but queue not full
583 * >0 - unexpected error. MQE_xxx returned
584 */
585static int send_noop_message(void *cb, struct gru_message_queue_desc *mqd,
586 void *mesg)
587{
588 const struct message_header noop_header = {
589 .present = MQS_NOOP, .lines = 1};
590 unsigned long m;
591 int substatus, ret;
592 struct message_header save_mhdr, *mhdr = mesg;
593
594 STAT(mesq_noop);
595 save_mhdr = *mhdr;
596 *mhdr = noop_header;
597 gru_mesq(cb, mqd->mq_gpa, gru_get_tri(mhdr), 1, IMA);
598 ret = gru_wait(cb);
599
600 if (ret) {
601 substatus = gru_get_cb_message_queue_substatus(cb);
602 switch (substatus) {
603 case CBSS_NO_ERROR:
604 STAT(mesq_noop_unexpected_error);
605 ret = MQE_UNEXPECTED_CB_ERR;
606 break;
607 case CBSS_LB_OVERFLOWED:
608 STAT(mesq_noop_lb_overflow);
609 ret = MQE_CONGESTION;
610 break;
611 case CBSS_QLIMIT_REACHED:
612 STAT(mesq_noop_qlimit_reached);
613 ret = 0;
614 break;
615 case CBSS_AMO_NACKED:
616 STAT(mesq_noop_amo_nacked);
617 ret = MQE_CONGESTION;
618 break;
619 case CBSS_PUT_NACKED:
620 STAT(mesq_noop_put_nacked);
621 m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
622 gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, 1, 1,
623 IMA);
624 if (gru_wait(cb) == CBS_IDLE)
625 ret = MQIE_AGAIN;
626 else
627 ret = MQE_UNEXPECTED_CB_ERR;
628 break;
629 case CBSS_PAGE_OVERFLOW:
630 STAT(mesq_noop_page_overflow);
631 /* fallthru */
632 default:
633 BUG();
634 }
635 }
636 *mhdr = save_mhdr;
637 return ret;
638}
639
640/*
641 * Handle a gru_mesq full.
642 */
643static int send_message_queue_full(void *cb, struct gru_message_queue_desc *mqd,
644 void *mesg, int lines)
645{
646 union gru_mesqhead mqh;
647 unsigned int limit, head;
648 unsigned long avalue;
649 int half, qlines;
650
651 /* Determine if switching to first/second half of q */
652 avalue = gru_get_amo_value(cb);
653 head = gru_get_amo_value_head(cb);
654 limit = gru_get_amo_value_limit(cb);
655
656 qlines = mqd->qlines;
657 half = (limit != qlines);
658
659 if (half)
660 mqh = gru_mesq_head(qlines / 2 + 1, qlines);
661 else
662 mqh = gru_mesq_head(2, qlines / 2 + 1);
663
664 /* Try to get lock for switching head pointer */
665 gru_gamir(cb, EOP_IR_CLR, HSTATUS(mqd->mq_gpa, half), XTYPE_DW, IMA);
666 if (gru_wait(cb) != CBS_IDLE)
667 goto cberr;
668 if (!gru_get_amo_value(cb)) {
669 STAT(mesq_qf_locked);
670 return MQE_QUEUE_FULL;
671 }
672
673 /* Got the lock. Send optional NOP if queue not full, */
674 if (head != limit) {
675 if (send_noop_message(cb, mqd, mesg)) {
676 gru_gamir(cb, EOP_IR_INC, HSTATUS(mqd->mq_gpa, half),
677 XTYPE_DW, IMA);
678 if (gru_wait(cb) != CBS_IDLE)
679 goto cberr;
680 STAT(mesq_qf_noop_not_full);
681 return MQIE_AGAIN;
682 }
683 avalue++;
684 }
685
686 /* Then flip queuehead to other half of queue. */
687 gru_gamer(cb, EOP_ERR_CSWAP, mqd->mq_gpa, XTYPE_DW, mqh.val, avalue,
688 IMA);
689 if (gru_wait(cb) != CBS_IDLE)
690 goto cberr;
691
692 /* If not successfully in swapping queue head, clear the hstatus lock */
693 if (gru_get_amo_value(cb) != avalue) {
694 STAT(mesq_qf_switch_head_failed);
695 gru_gamir(cb, EOP_IR_INC, HSTATUS(mqd->mq_gpa, half), XTYPE_DW,
696 IMA);
697 if (gru_wait(cb) != CBS_IDLE)
698 goto cberr;
699 }
700 return MQIE_AGAIN;
701cberr:
702 STAT(mesq_qf_unexpected_error);
703 return MQE_UNEXPECTED_CB_ERR;
704}
705
706/*
707 * Handle a PUT failure. Note: if message was a 2-line message, one of the
708 * lines might have successfully have been written. Before sending the
709 * message, "present" must be cleared in BOTH lines to prevent the receiver
710 * from prematurely seeing the full message.
711 */
712static int send_message_put_nacked(void *cb, struct gru_message_queue_desc *mqd,
713 void *mesg, int lines)
714{
715 unsigned long m, *val = mesg, gpa, save;
716 int ret;
717
718 m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
719 if (lines == 2) {
720 gru_vset(cb, m, 0, XTYPE_CL, lines, 1, IMA);
721 if (gru_wait(cb) != CBS_IDLE)
722 return MQE_UNEXPECTED_CB_ERR;
723 }
724 gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, lines, 1, IMA);
725 if (gru_wait(cb) != CBS_IDLE)
726 return MQE_UNEXPECTED_CB_ERR;
727
728 if (!mqd->interrupt_vector)
729 return MQE_OK;
730
731 /*
732 * Send a cross-partition interrupt to the SSI that contains the target
733 * message queue. Normally, the interrupt is automatically delivered by
734 * hardware but some error conditions require explicit delivery.
735 * Use the GRU to deliver the interrupt. Otherwise partition failures
736 * could cause unrecovered errors.
737 */
738 gpa = uv_global_gru_mmr_address(mqd->interrupt_pnode, UVH_IPI_INT);
739 save = *val;
740 *val = uv_hub_ipi_value(mqd->interrupt_apicid, mqd->interrupt_vector,
741 dest_Fixed);
742 gru_vstore_phys(cb, gpa, gru_get_tri(mesg), IAA_REGISTER, IMA);
743 ret = gru_wait(cb);
744 *val = save;
745 if (ret != CBS_IDLE)
746 return MQE_UNEXPECTED_CB_ERR;
747 return MQE_OK;
748}
749
750/*
751 * Handle a gru_mesq failure. Some of these failures are software recoverable
752 * or retryable.
753 */
754static int send_message_failure(void *cb, struct gru_message_queue_desc *mqd,
755 void *mesg, int lines)
756{
757 int substatus, ret = 0;
758
759 substatus = gru_get_cb_message_queue_substatus(cb);
760 switch (substatus) {
761 case CBSS_NO_ERROR:
762 STAT(mesq_send_unexpected_error);
763 ret = MQE_UNEXPECTED_CB_ERR;
764 break;
765 case CBSS_LB_OVERFLOWED:
766 STAT(mesq_send_lb_overflow);
767 ret = MQE_CONGESTION;
768 break;
769 case CBSS_QLIMIT_REACHED:
770 STAT(mesq_send_qlimit_reached);
771 ret = send_message_queue_full(cb, mqd, mesg, lines);
772 break;
773 case CBSS_AMO_NACKED:
774 STAT(mesq_send_amo_nacked);
775 ret = MQE_CONGESTION;
776 break;
777 case CBSS_PUT_NACKED:
778 STAT(mesq_send_put_nacked);
779 ret = send_message_put_nacked(cb, mqd, mesg, lines);
780 break;
781 case CBSS_PAGE_OVERFLOW:
782 STAT(mesq_page_overflow);
783 /* fallthru */
784 default:
785 BUG();
786 }
787 return ret;
788}
789
790/*
791 * Send a message to a message queue
792 * mqd message queue descriptor
793 * mesg message. ust be vaddr within a GSEG
794 * bytes message size (<= 2 CL)
795 */
796int gru_send_message_gpa(struct gru_message_queue_desc *mqd, void *mesg,
797 unsigned int bytes)
798{
799 struct message_header *mhdr;
800 void *cb;
801 void *dsr;
802 int istatus, clines, ret;
803
804 STAT(mesq_send);
805 BUG_ON(bytes < sizeof(int) || bytes > 2 * GRU_CACHE_LINE_BYTES);
806
807 clines = DIV_ROUND_UP(bytes, GRU_CACHE_LINE_BYTES);
808 if (gru_get_cpu_resources(bytes, &cb, &dsr))
809 return MQE_BUG_NO_RESOURCES;
810 memcpy(dsr, mesg, bytes);
811 mhdr = dsr;
812 mhdr->present = MQS_FULL;
813 mhdr->lines = clines;
814 if (clines == 2) {
815 mhdr->present2 = get_present2(mhdr);
816 restore_present2(mhdr, MQS_FULL);
817 }
818
819 do {
820 ret = MQE_OK;
821 gru_mesq(cb, mqd->mq_gpa, gru_get_tri(mhdr), clines, IMA);
822 istatus = gru_wait(cb);
823 if (istatus != CBS_IDLE)
824 ret = send_message_failure(cb, mqd, dsr, clines);
825 } while (ret == MQIE_AGAIN);
826 gru_free_cpu_resources(cb, dsr);
827
828 if (ret)
829 STAT(mesq_send_failed);
830 return ret;
831}
832EXPORT_SYMBOL_GPL(gru_send_message_gpa);
833
834/*
835 * Advance the receive pointer for the queue to the next message.
836 */
837void gru_free_message(struct gru_message_queue_desc *mqd, void *mesg)
838{
839 struct message_queue *mq = mqd->mq;
840 struct message_header *mhdr = mq->next;
841 void *next, *pnext;
842 int half = -1;
843 int lines = mhdr->lines;
844
845 if (lines == 2)
846 restore_present2(mhdr, MQS_EMPTY);
847 mhdr->present = MQS_EMPTY;
848
849 pnext = mq->next;
850 next = pnext + GRU_CACHE_LINE_BYTES * lines;
851 if (next == mq->limit) {
852 next = mq->start;
853 half = 1;
854 } else if (pnext < mq->start2 && next >= mq->start2) {
855 half = 0;
856 }
857
858 if (half >= 0)
859 mq->hstatus[half] = 1;
860 mq->next = next;
861}
862EXPORT_SYMBOL_GPL(gru_free_message);
863
864/*
865 * Get next message from message queue. Return NULL if no message
866 * present. User must call next_message() to move to next message.
867 * rmq message queue
868 */
869void *gru_get_next_message(struct gru_message_queue_desc *mqd)
870{
871 struct message_queue *mq = mqd->mq;
872 struct message_header *mhdr = mq->next;
873 int present = mhdr->present;
874
875 /* skip NOOP messages */
876 while (present == MQS_NOOP) {
877 gru_free_message(mqd, mhdr);
878 mhdr = mq->next;
879 present = mhdr->present;
880 }
881
882 /* Wait for both halves of 2 line messages */
883 if (present == MQS_FULL && mhdr->lines == 2 &&
884 get_present2(mhdr) == MQS_EMPTY)
885 present = MQS_EMPTY;
886
887 if (!present) {
888 STAT(mesq_receive_none);
889 return NULL;
890 }
891
892 if (mhdr->lines == 2)
893 restore_present2(mhdr, mhdr->present2);
894
895 STAT(mesq_receive);
896 return mhdr;
897}
898EXPORT_SYMBOL_GPL(gru_get_next_message);
899
900/* ---------------------- GRU DATA COPY FUNCTIONS ---------------------------*/
901
902/*
903 * Load a DW from a global GPA. The GPA can be a memory or MMR address.
904 */
905int gru_read_gpa(unsigned long *value, unsigned long gpa)
906{
907 void *cb;
908 void *dsr;
909 int ret, iaa;
910
911 STAT(read_gpa);
912 if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr))
913 return MQE_BUG_NO_RESOURCES;
914 iaa = gpa >> 62;
915 gru_vload_phys(cb, gpa, gru_get_tri(dsr), iaa, IMA);
916 ret = gru_wait(cb);
917 if (ret == CBS_IDLE)
918 *value = *(unsigned long *)dsr;
919 gru_free_cpu_resources(cb, dsr);
920 return ret;
921}
922EXPORT_SYMBOL_GPL(gru_read_gpa);
923
924
925/*
926 * Copy a block of data using the GRU resources
927 */
928int gru_copy_gpa(unsigned long dest_gpa, unsigned long src_gpa,
929 unsigned int bytes)
930{
931 void *cb;
932 void *dsr;
933 int ret;
934
935 STAT(copy_gpa);
936 if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr))
937 return MQE_BUG_NO_RESOURCES;
938 gru_bcopy(cb, src_gpa, dest_gpa, gru_get_tri(dsr),
939 XTYPE_B, bytes, GRU_NUM_KERNEL_DSR_CL, IMA);
940 ret = gru_wait(cb);
941 gru_free_cpu_resources(cb, dsr);
942 return ret;
943}
944EXPORT_SYMBOL_GPL(gru_copy_gpa);
945
946/* ------------------- KERNEL QUICKTESTS RUN AT STARTUP ----------------*/
947/* Temp - will delete after we gain confidence in the GRU */
948
949static int quicktest0(unsigned long arg)
950{
951 unsigned long word0;
952 unsigned long word1;
953 void *cb;
954 void *dsr;
955 unsigned long *p;
956 int ret = -EIO;
957
958 if (gru_get_cpu_resources(GRU_CACHE_LINE_BYTES, &cb, &dsr))
959 return MQE_BUG_NO_RESOURCES;
960 p = dsr;
961 word0 = MAGIC;
962 word1 = 0;
963
964 gru_vload(cb, uv_gpa(&word0), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA);
965 if (gru_wait(cb) != CBS_IDLE) {
966 printk(KERN_DEBUG "GRU:%d quicktest0: CBR failure 1\n", smp_processor_id());
967 goto done;
968 }
969
970 if (*p != MAGIC) {
971 printk(KERN_DEBUG "GRU:%d quicktest0 bad magic 0x%lx\n", smp_processor_id(), *p);
972 goto done;
973 }
974 gru_vstore(cb, uv_gpa(&word1), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA);
975 if (gru_wait(cb) != CBS_IDLE) {
976 printk(KERN_DEBUG "GRU:%d quicktest0: CBR failure 2\n", smp_processor_id());
977 goto done;
978 }
979
980 if (word0 != word1 || word1 != MAGIC) {
981 printk(KERN_DEBUG
982 "GRU:%d quicktest0 err: found 0x%lx, expected 0x%lx\n",
983 smp_processor_id(), word1, MAGIC);
984 goto done;
985 }
986 ret = 0;
987
988done:
989 gru_free_cpu_resources(cb, dsr);
990 return ret;
991}
992
993#define ALIGNUP(p, q) ((void *)(((unsigned long)(p) + (q) - 1) & ~(q - 1)))
994
995static int quicktest1(unsigned long arg)
996{
997 struct gru_message_queue_desc mqd;
998 void *p, *mq;
999 unsigned long *dw;
1000 int i, ret = -EIO;
1001 char mes[GRU_CACHE_LINE_BYTES], *m;
1002
1003 /* Need 1K cacheline aligned that does not cross page boundary */
1004 p = kmalloc(4096, 0);
1005 if (p == NULL)
1006 return -ENOMEM;
1007 mq = ALIGNUP(p, 1024);
1008 memset(mes, 0xee, sizeof(mes));
1009 dw = mq;
1010
1011 gru_create_message_queue(&mqd, mq, 8 * GRU_CACHE_LINE_BYTES, 0, 0, 0);
1012 for (i = 0; i < 6; i++) {
1013 mes[8] = i;
1014 do {
1015 ret = gru_send_message_gpa(&mqd, mes, sizeof(mes));
1016 } while (ret == MQE_CONGESTION);
1017 if (ret)
1018 break;
1019 }
1020 if (ret != MQE_QUEUE_FULL || i != 4) {
1021 printk(KERN_DEBUG "GRU:%d quicktest1: unexpect status %d, i %d\n",
1022 smp_processor_id(), ret, i);
1023 goto done;
1024 }
1025
1026 for (i = 0; i < 6; i++) {
1027 m = gru_get_next_message(&mqd);
1028 if (!m || m[8] != i)
1029 break;
1030 gru_free_message(&mqd, m);
1031 }
1032 if (i != 4) {
1033 printk(KERN_DEBUG "GRU:%d quicktest2: bad message, i %d, m %p, m8 %d\n",
1034 smp_processor_id(), i, m, m ? m[8] : -1);
1035 goto done;
1036 }
1037 ret = 0;
1038
1039done:
1040 kfree(p);
1041 return ret;
1042}
1043
1044static int quicktest2(unsigned long arg)
1045{
1046 static DECLARE_COMPLETION(cmp);
1047 unsigned long han;
1048 int blade_id = 0;
1049 int numcb = 4;
1050 int ret = 0;
1051 unsigned long *buf;
1052 void *cb0, *cb;
1053 struct gru_control_block_status *gen;
1054 int i, k, istatus, bytes;
1055
1056 bytes = numcb * 4 * 8;
1057 buf = kmalloc(bytes, GFP_KERNEL);
1058 if (!buf)
1059 return -ENOMEM;
1060
1061 ret = -EBUSY;
1062 han = gru_reserve_async_resources(blade_id, numcb, 0, &cmp);
1063 if (!han)
1064 goto done;
1065
1066 gru_lock_async_resource(han, &cb0, NULL);
1067 memset(buf, 0xee, bytes);
1068 for (i = 0; i < numcb; i++)
1069 gru_vset(cb0 + i * GRU_HANDLE_STRIDE, uv_gpa(&buf[i * 4]), 0,
1070 XTYPE_DW, 4, 1, IMA_INTERRUPT);
1071
1072 ret = 0;
1073 k = numcb;
1074 do {
1075 gru_wait_async_cbr(han);
1076 for (i = 0; i < numcb; i++) {
1077 cb = cb0 + i * GRU_HANDLE_STRIDE;
1078 istatus = gru_check_status(cb);
1079 if (istatus != CBS_ACTIVE && istatus != CBS_CALL_OS)
1080 break;
1081 }
1082 if (i == numcb)
1083 continue;
1084 if (istatus != CBS_IDLE) {
1085 printk(KERN_DEBUG "GRU:%d quicktest2: cb %d, exception\n", smp_processor_id(), i);
1086 ret = -EFAULT;
1087 } else if (buf[4 * i] || buf[4 * i + 1] || buf[4 * i + 2] ||
1088 buf[4 * i + 3]) {
1089 printk(KERN_DEBUG "GRU:%d quicktest2:cb %d, buf 0x%lx, 0x%lx, 0x%lx, 0x%lx\n",
1090 smp_processor_id(), i, buf[4 * i], buf[4 * i + 1], buf[4 * i + 2], buf[4 * i + 3]);
1091 ret = -EIO;
1092 }
1093 k--;
1094 gen = cb;
1095 gen->istatus = CBS_CALL_OS; /* don't handle this CBR again */
1096 } while (k);
1097 BUG_ON(cmp.done);
1098
1099 gru_unlock_async_resource(han);
1100 gru_release_async_resources(han);
1101done:
1102 kfree(buf);
1103 return ret;
1104}
1105
1106#define BUFSIZE 200
1107static int quicktest3(unsigned long arg)
1108{
1109 char buf1[BUFSIZE], buf2[BUFSIZE];
1110 int ret = 0;
1111
1112 memset(buf2, 0, sizeof(buf2));
1113 memset(buf1, get_cycles() & 255, sizeof(buf1));
1114 gru_copy_gpa(uv_gpa(buf2), uv_gpa(buf1), BUFSIZE);
1115 if (memcmp(buf1, buf2, BUFSIZE)) {
1116 printk(KERN_DEBUG "GRU:%d quicktest3 error\n", smp_processor_id());
1117 ret = -EIO;
1118 }
1119 return ret;
1120}
1121
1122/*
1123 * Debugging only. User hook for various kernel tests
1124 * of driver & gru.
1125 */
1126int gru_ktest(unsigned long arg)
1127{
1128 int ret = -EINVAL;
1129
1130 switch (arg & 0xff) {
1131 case 0:
1132 ret = quicktest0(arg);
1133 break;
1134 case 1:
1135 ret = quicktest1(arg);
1136 break;
1137 case 2:
1138 ret = quicktest2(arg);
1139 break;
1140 case 3:
1141 ret = quicktest3(arg);
1142 break;
1143 case 99:
1144 ret = gru_free_kernel_contexts();
1145 break;
1146 }
1147 return ret;
1148
1149}
1150
1151int gru_kservices_init(void)
1152{
1153 return 0;
1154}
1155
1156void gru_kservices_exit(void)
1157{
1158 if (gru_free_kernel_contexts())
1159 BUG();
1160}
1161
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * SN Platform GRU Driver
4 *
5 * KERNEL SERVICES THAT USE THE GRU
6 *
7 * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
8 */
9
10#include <linux/kernel.h>
11#include <linux/errno.h>
12#include <linux/slab.h>
13#include <linux/mm.h>
14#include <linux/spinlock.h>
15#include <linux/device.h>
16#include <linux/miscdevice.h>
17#include <linux/proc_fs.h>
18#include <linux/interrupt.h>
19#include <linux/sync_core.h>
20#include <linux/uaccess.h>
21#include <linux/delay.h>
22#include <linux/export.h>
23#include <asm/io_apic.h>
24#include "gru.h"
25#include "grulib.h"
26#include "grutables.h"
27#include "grukservices.h"
28#include "gru_instructions.h"
29#include <asm/uv/uv_hub.h>
30
31/*
32 * Kernel GRU Usage
33 *
34 * The following is an interim algorithm for management of kernel GRU
35 * resources. This will likely be replaced when we better understand the
36 * kernel/user requirements.
37 *
38 * Blade percpu resources reserved for kernel use. These resources are
39 * reserved whenever the kernel context for the blade is loaded. Note
40 * that the kernel context is not guaranteed to be always available. It is
41 * loaded on demand & can be stolen by a user if the user demand exceeds the
42 * kernel demand. The kernel can always reload the kernel context but
43 * a SLEEP may be required!!!.
44 *
45 * Async Overview:
46 *
47 * Each blade has one "kernel context" that owns GRU kernel resources
48 * located on the blade. Kernel drivers use GRU resources in this context
49 * for sending messages, zeroing memory, etc.
50 *
51 * The kernel context is dynamically loaded on demand. If it is not in
52 * use by the kernel, the kernel context can be unloaded & given to a user.
53 * The kernel context will be reloaded when needed. This may require that
54 * a context be stolen from a user.
55 * NOTE: frequent unloading/reloading of the kernel context is
56 * expensive. We are depending on batch schedulers, cpusets, sane
57 * drivers or some other mechanism to prevent the need for frequent
58 * stealing/reloading.
59 *
60 * The kernel context consists of two parts:
61 * - 1 CB & a few DSRs that are reserved for each cpu on the blade.
62 * Each cpu has it's own private resources & does not share them
63 * with other cpus. These resources are used serially, ie,
64 * locked, used & unlocked on each call to a function in
65 * grukservices.
66 * (Now that we have dynamic loading of kernel contexts, I
67 * may rethink this & allow sharing between cpus....)
68 *
69 * - Additional resources can be reserved long term & used directly
70 * by UV drivers located in the kernel. Drivers using these GRU
71 * resources can use asynchronous GRU instructions that send
72 * interrupts on completion.
73 * - these resources must be explicitly locked/unlocked
74 * - locked resources prevent (obviously) the kernel
75 * context from being unloaded.
76 * - drivers using these resource directly issue their own
77 * GRU instruction and must wait/check completion.
78 *
79 * When these resources are reserved, the caller can optionally
80 * associate a wait_queue with the resources and use asynchronous
81 * GRU instructions. When an async GRU instruction completes, the
82 * driver will do a wakeup on the event.
83 *
84 */
85
86
87#define ASYNC_HAN_TO_BID(h) ((h) - 1)
88#define ASYNC_BID_TO_HAN(b) ((b) + 1)
89#define ASYNC_HAN_TO_BS(h) gru_base[ASYNC_HAN_TO_BID(h)]
90
91#define GRU_NUM_KERNEL_CBR 1
92#define GRU_NUM_KERNEL_DSR_BYTES 256
93#define GRU_NUM_KERNEL_DSR_CL (GRU_NUM_KERNEL_DSR_BYTES / \
94 GRU_CACHE_LINE_BYTES)
95
96/* GRU instruction attributes for all instructions */
97#define IMA IMA_CB_DELAY
98
99/* GRU cacheline size is always 64 bytes - even on arches with 128 byte lines */
100#define __gru_cacheline_aligned__ \
101 __attribute__((__aligned__(GRU_CACHE_LINE_BYTES)))
102
103#define MAGIC 0x1234567887654321UL
104
105/* Default retry count for GRU errors on kernel instructions */
106#define EXCEPTION_RETRY_LIMIT 3
107
108/* Status of message queue sections */
109#define MQS_EMPTY 0
110#define MQS_FULL 1
111#define MQS_NOOP 2
112
113/*----------------- RESOURCE MANAGEMENT -------------------------------------*/
114/* optimized for x86_64 */
115struct message_queue {
116 union gru_mesqhead head __gru_cacheline_aligned__; /* CL 0 */
117 int qlines; /* DW 1 */
118 long hstatus[2];
119 void *next __gru_cacheline_aligned__;/* CL 1 */
120 void *limit;
121 void *start;
122 void *start2;
123 char data ____cacheline_aligned; /* CL 2 */
124};
125
126/* First word in every message - used by mesq interface */
127struct message_header {
128 char present;
129 char present2;
130 char lines;
131 char fill;
132};
133
134#define HSTATUS(mq, h) ((mq) + offsetof(struct message_queue, hstatus[h]))
135
136/*
137 * Reload the blade's kernel context into a GRU chiplet. Called holding
138 * the bs_kgts_sema for READ. Will steal user contexts if necessary.
139 */
140static void gru_load_kernel_context(struct gru_blade_state *bs, int blade_id)
141{
142 struct gru_state *gru;
143 struct gru_thread_state *kgts;
144 void *vaddr;
145 int ctxnum, ncpus;
146
147 up_read(&bs->bs_kgts_sema);
148 down_write(&bs->bs_kgts_sema);
149
150 if (!bs->bs_kgts) {
151 do {
152 bs->bs_kgts = gru_alloc_gts(NULL, 0, 0, 0, 0, 0);
153 if (!IS_ERR(bs->bs_kgts))
154 break;
155 msleep(1);
156 } while (true);
157 bs->bs_kgts->ts_user_blade_id = blade_id;
158 }
159 kgts = bs->bs_kgts;
160
161 if (!kgts->ts_gru) {
162 STAT(load_kernel_context);
163 ncpus = uv_blade_nr_possible_cpus(blade_id);
164 kgts->ts_cbr_au_count = GRU_CB_COUNT_TO_AU(
165 GRU_NUM_KERNEL_CBR * ncpus + bs->bs_async_cbrs);
166 kgts->ts_dsr_au_count = GRU_DS_BYTES_TO_AU(
167 GRU_NUM_KERNEL_DSR_BYTES * ncpus +
168 bs->bs_async_dsr_bytes);
169 while (!gru_assign_gru_context(kgts)) {
170 msleep(1);
171 gru_steal_context(kgts);
172 }
173 gru_load_context(kgts);
174 gru = bs->bs_kgts->ts_gru;
175 vaddr = gru->gs_gru_base_vaddr;
176 ctxnum = kgts->ts_ctxnum;
177 bs->kernel_cb = get_gseg_base_address_cb(vaddr, ctxnum, 0);
178 bs->kernel_dsr = get_gseg_base_address_ds(vaddr, ctxnum, 0);
179 }
180 downgrade_write(&bs->bs_kgts_sema);
181}
182
183/*
184 * Free all kernel contexts that are not currently in use.
185 * Returns 0 if all freed, else number of inuse context.
186 */
187static int gru_free_kernel_contexts(void)
188{
189 struct gru_blade_state *bs;
190 struct gru_thread_state *kgts;
191 int bid, ret = 0;
192
193 for (bid = 0; bid < GRU_MAX_BLADES; bid++) {
194 bs = gru_base[bid];
195 if (!bs)
196 continue;
197
198 /* Ignore busy contexts. Don't want to block here. */
199 if (down_write_trylock(&bs->bs_kgts_sema)) {
200 kgts = bs->bs_kgts;
201 if (kgts && kgts->ts_gru)
202 gru_unload_context(kgts, 0);
203 bs->bs_kgts = NULL;
204 up_write(&bs->bs_kgts_sema);
205 kfree(kgts);
206 } else {
207 ret++;
208 }
209 }
210 return ret;
211}
212
213/*
214 * Lock & load the kernel context for the specified blade.
215 */
216static struct gru_blade_state *gru_lock_kernel_context(int blade_id)
217{
218 struct gru_blade_state *bs;
219 int bid;
220
221 STAT(lock_kernel_context);
222again:
223 bid = blade_id < 0 ? uv_numa_blade_id() : blade_id;
224 bs = gru_base[bid];
225
226 /* Handle the case where migration occurred while waiting for the sema */
227 down_read(&bs->bs_kgts_sema);
228 if (blade_id < 0 && bid != uv_numa_blade_id()) {
229 up_read(&bs->bs_kgts_sema);
230 goto again;
231 }
232 if (!bs->bs_kgts || !bs->bs_kgts->ts_gru)
233 gru_load_kernel_context(bs, bid);
234 return bs;
235
236}
237
238/*
239 * Unlock the kernel context for the specified blade. Context is not
240 * unloaded but may be stolen before next use.
241 */
242static void gru_unlock_kernel_context(int blade_id)
243{
244 struct gru_blade_state *bs;
245
246 bs = gru_base[blade_id];
247 up_read(&bs->bs_kgts_sema);
248 STAT(unlock_kernel_context);
249}
250
251/*
252 * Reserve & get pointers to the DSR/CBRs reserved for the current cpu.
253 * - returns with preemption disabled
254 */
255static int gru_get_cpu_resources(int dsr_bytes, void **cb, void **dsr)
256{
257 struct gru_blade_state *bs;
258 int lcpu;
259
260 BUG_ON(dsr_bytes > GRU_NUM_KERNEL_DSR_BYTES);
261 preempt_disable();
262 bs = gru_lock_kernel_context(-1);
263 lcpu = uv_blade_processor_id();
264 *cb = bs->kernel_cb + lcpu * GRU_HANDLE_STRIDE;
265 *dsr = bs->kernel_dsr + lcpu * GRU_NUM_KERNEL_DSR_BYTES;
266 return 0;
267}
268
269/*
270 * Free the current cpus reserved DSR/CBR resources.
271 */
272static void gru_free_cpu_resources(void *cb, void *dsr)
273{
274 gru_unlock_kernel_context(uv_numa_blade_id());
275 preempt_enable();
276}
277
278/*
279 * Reserve GRU resources to be used asynchronously.
280 * Note: currently supports only 1 reservation per blade.
281 *
282 * input:
283 * blade_id - blade on which resources should be reserved
284 * cbrs - number of CBRs
285 * dsr_bytes - number of DSR bytes needed
286 * output:
287 * handle to identify resource
288 * (0 = async resources already reserved)
289 */
290unsigned long gru_reserve_async_resources(int blade_id, int cbrs, int dsr_bytes,
291 struct completion *cmp)
292{
293 struct gru_blade_state *bs;
294 struct gru_thread_state *kgts;
295 int ret = 0;
296
297 bs = gru_base[blade_id];
298
299 down_write(&bs->bs_kgts_sema);
300
301 /* Verify no resources already reserved */
302 if (bs->bs_async_dsr_bytes + bs->bs_async_cbrs)
303 goto done;
304 bs->bs_async_dsr_bytes = dsr_bytes;
305 bs->bs_async_cbrs = cbrs;
306 bs->bs_async_wq = cmp;
307 kgts = bs->bs_kgts;
308
309 /* Resources changed. Unload context if already loaded */
310 if (kgts && kgts->ts_gru)
311 gru_unload_context(kgts, 0);
312 ret = ASYNC_BID_TO_HAN(blade_id);
313
314done:
315 up_write(&bs->bs_kgts_sema);
316 return ret;
317}
318
319/*
320 * Release async resources previously reserved.
321 *
322 * input:
323 * han - handle to identify resources
324 */
325void gru_release_async_resources(unsigned long han)
326{
327 struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
328
329 down_write(&bs->bs_kgts_sema);
330 bs->bs_async_dsr_bytes = 0;
331 bs->bs_async_cbrs = 0;
332 bs->bs_async_wq = NULL;
333 up_write(&bs->bs_kgts_sema);
334}
335
336/*
337 * Wait for async GRU instructions to complete.
338 *
339 * input:
340 * han - handle to identify resources
341 */
342void gru_wait_async_cbr(unsigned long han)
343{
344 struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
345
346 wait_for_completion(bs->bs_async_wq);
347 mb();
348}
349
350/*
351 * Lock previous reserved async GRU resources
352 *
353 * input:
354 * han - handle to identify resources
355 * output:
356 * cb - pointer to first CBR
357 * dsr - pointer to first DSR
358 */
359void gru_lock_async_resource(unsigned long han, void **cb, void **dsr)
360{
361 struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
362 int blade_id = ASYNC_HAN_TO_BID(han);
363 int ncpus;
364
365 gru_lock_kernel_context(blade_id);
366 ncpus = uv_blade_nr_possible_cpus(blade_id);
367 if (cb)
368 *cb = bs->kernel_cb + ncpus * GRU_HANDLE_STRIDE;
369 if (dsr)
370 *dsr = bs->kernel_dsr + ncpus * GRU_NUM_KERNEL_DSR_BYTES;
371}
372
373/*
374 * Unlock previous reserved async GRU resources
375 *
376 * input:
377 * han - handle to identify resources
378 */
379void gru_unlock_async_resource(unsigned long han)
380{
381 int blade_id = ASYNC_HAN_TO_BID(han);
382
383 gru_unlock_kernel_context(blade_id);
384}
385
386/*----------------------------------------------------------------------*/
387int gru_get_cb_exception_detail(void *cb,
388 struct control_block_extended_exc_detail *excdet)
389{
390 struct gru_control_block_extended *cbe;
391 struct gru_thread_state *kgts = NULL;
392 unsigned long off;
393 int cbrnum, bid;
394
395 /*
396 * Locate kgts for cb. This algorithm is SLOW but
397 * this function is rarely called (ie., almost never).
398 * Performance does not matter.
399 */
400 for_each_possible_blade(bid) {
401 if (!gru_base[bid])
402 break;
403 kgts = gru_base[bid]->bs_kgts;
404 if (!kgts || !kgts->ts_gru)
405 continue;
406 off = cb - kgts->ts_gru->gs_gru_base_vaddr;
407 if (off < GRU_SIZE)
408 break;
409 kgts = NULL;
410 }
411 BUG_ON(!kgts);
412 cbrnum = thread_cbr_number(kgts, get_cb_number(cb));
413 cbe = get_cbe(GRUBASE(cb), cbrnum);
414 gru_flush_cache(cbe); /* CBE not coherent */
415 sync_core();
416 excdet->opc = cbe->opccpy;
417 excdet->exopc = cbe->exopccpy;
418 excdet->ecause = cbe->ecause;
419 excdet->exceptdet0 = cbe->idef1upd;
420 excdet->exceptdet1 = cbe->idef3upd;
421 gru_flush_cache(cbe);
422 return 0;
423}
424
425static char *gru_get_cb_exception_detail_str(int ret, void *cb,
426 char *buf, int size)
427{
428 struct gru_control_block_status *gen = cb;
429 struct control_block_extended_exc_detail excdet;
430
431 if (ret > 0 && gen->istatus == CBS_EXCEPTION) {
432 gru_get_cb_exception_detail(cb, &excdet);
433 snprintf(buf, size,
434 "GRU:%d exception: cb %p, opc %d, exopc %d, ecause 0x%x,"
435 "excdet0 0x%lx, excdet1 0x%x", smp_processor_id(),
436 gen, excdet.opc, excdet.exopc, excdet.ecause,
437 excdet.exceptdet0, excdet.exceptdet1);
438 } else {
439 snprintf(buf, size, "No exception");
440 }
441 return buf;
442}
443
444static int gru_wait_idle_or_exception(struct gru_control_block_status *gen)
445{
446 while (gen->istatus >= CBS_ACTIVE) {
447 cpu_relax();
448 barrier();
449 }
450 return gen->istatus;
451}
452
453static int gru_retry_exception(void *cb)
454{
455 struct gru_control_block_status *gen = cb;
456 struct control_block_extended_exc_detail excdet;
457 int retry = EXCEPTION_RETRY_LIMIT;
458
459 while (1) {
460 if (gru_wait_idle_or_exception(gen) == CBS_IDLE)
461 return CBS_IDLE;
462 if (gru_get_cb_message_queue_substatus(cb))
463 return CBS_EXCEPTION;
464 gru_get_cb_exception_detail(cb, &excdet);
465 if ((excdet.ecause & ~EXCEPTION_RETRY_BITS) ||
466 (excdet.cbrexecstatus & CBR_EXS_ABORT_OCC))
467 break;
468 if (retry-- == 0)
469 break;
470 gen->icmd = 1;
471 gru_flush_cache(gen);
472 }
473 return CBS_EXCEPTION;
474}
475
476int gru_check_status_proc(void *cb)
477{
478 struct gru_control_block_status *gen = cb;
479 int ret;
480
481 ret = gen->istatus;
482 if (ret == CBS_EXCEPTION)
483 ret = gru_retry_exception(cb);
484 rmb();
485 return ret;
486
487}
488
489int gru_wait_proc(void *cb)
490{
491 struct gru_control_block_status *gen = cb;
492 int ret;
493
494 ret = gru_wait_idle_or_exception(gen);
495 if (ret == CBS_EXCEPTION)
496 ret = gru_retry_exception(cb);
497 rmb();
498 return ret;
499}
500
501static void gru_abort(int ret, void *cb, char *str)
502{
503 char buf[GRU_EXC_STR_SIZE];
504
505 panic("GRU FATAL ERROR: %s - %s\n", str,
506 gru_get_cb_exception_detail_str(ret, cb, buf, sizeof(buf)));
507}
508
509void gru_wait_abort_proc(void *cb)
510{
511 int ret;
512
513 ret = gru_wait_proc(cb);
514 if (ret)
515 gru_abort(ret, cb, "gru_wait_abort");
516}
517
518
519/*------------------------------ MESSAGE QUEUES -----------------------------*/
520
521/* Internal status . These are NOT returned to the user. */
522#define MQIE_AGAIN -1 /* try again */
523
524
525/*
526 * Save/restore the "present" flag that is in the second line of 2-line
527 * messages
528 */
529static inline int get_present2(void *p)
530{
531 struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES;
532 return mhdr->present;
533}
534
535static inline void restore_present2(void *p, int val)
536{
537 struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES;
538 mhdr->present = val;
539}
540
541/*
542 * Create a message queue.
543 * qlines - message queue size in cache lines. Includes 2-line header.
544 */
545int gru_create_message_queue(struct gru_message_queue_desc *mqd,
546 void *p, unsigned int bytes, int nasid, int vector, int apicid)
547{
548 struct message_queue *mq = p;
549 unsigned int qlines;
550
551 qlines = bytes / GRU_CACHE_LINE_BYTES - 2;
552 memset(mq, 0, bytes);
553 mq->start = &mq->data;
554 mq->start2 = &mq->data + (qlines / 2 - 1) * GRU_CACHE_LINE_BYTES;
555 mq->next = &mq->data;
556 mq->limit = &mq->data + (qlines - 2) * GRU_CACHE_LINE_BYTES;
557 mq->qlines = qlines;
558 mq->hstatus[0] = 0;
559 mq->hstatus[1] = 1;
560 mq->head = gru_mesq_head(2, qlines / 2 + 1);
561 mqd->mq = mq;
562 mqd->mq_gpa = uv_gpa(mq);
563 mqd->qlines = qlines;
564 mqd->interrupt_pnode = nasid >> 1;
565 mqd->interrupt_vector = vector;
566 mqd->interrupt_apicid = apicid;
567 return 0;
568}
569EXPORT_SYMBOL_GPL(gru_create_message_queue);
570
571/*
572 * Send a NOOP message to a message queue
573 * Returns:
574 * 0 - if queue is full after the send. This is the normal case
575 * but various races can change this.
576 * -1 - if mesq sent successfully but queue not full
577 * >0 - unexpected error. MQE_xxx returned
578 */
579static int send_noop_message(void *cb, struct gru_message_queue_desc *mqd,
580 void *mesg)
581{
582 const struct message_header noop_header = {
583 .present = MQS_NOOP, .lines = 1};
584 unsigned long m;
585 int substatus, ret;
586 struct message_header save_mhdr, *mhdr = mesg;
587
588 STAT(mesq_noop);
589 save_mhdr = *mhdr;
590 *mhdr = noop_header;
591 gru_mesq(cb, mqd->mq_gpa, gru_get_tri(mhdr), 1, IMA);
592 ret = gru_wait(cb);
593
594 if (ret) {
595 substatus = gru_get_cb_message_queue_substatus(cb);
596 switch (substatus) {
597 case CBSS_NO_ERROR:
598 STAT(mesq_noop_unexpected_error);
599 ret = MQE_UNEXPECTED_CB_ERR;
600 break;
601 case CBSS_LB_OVERFLOWED:
602 STAT(mesq_noop_lb_overflow);
603 ret = MQE_CONGESTION;
604 break;
605 case CBSS_QLIMIT_REACHED:
606 STAT(mesq_noop_qlimit_reached);
607 ret = 0;
608 break;
609 case CBSS_AMO_NACKED:
610 STAT(mesq_noop_amo_nacked);
611 ret = MQE_CONGESTION;
612 break;
613 case CBSS_PUT_NACKED:
614 STAT(mesq_noop_put_nacked);
615 m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
616 gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, 1, 1,
617 IMA);
618 if (gru_wait(cb) == CBS_IDLE)
619 ret = MQIE_AGAIN;
620 else
621 ret = MQE_UNEXPECTED_CB_ERR;
622 break;
623 case CBSS_PAGE_OVERFLOW:
624 STAT(mesq_noop_page_overflow);
625 fallthrough;
626 default:
627 BUG();
628 }
629 }
630 *mhdr = save_mhdr;
631 return ret;
632}
633
634/*
635 * Handle a gru_mesq full.
636 */
637static int send_message_queue_full(void *cb, struct gru_message_queue_desc *mqd,
638 void *mesg, int lines)
639{
640 union gru_mesqhead mqh;
641 unsigned int limit, head;
642 unsigned long avalue;
643 int half, qlines;
644
645 /* Determine if switching to first/second half of q */
646 avalue = gru_get_amo_value(cb);
647 head = gru_get_amo_value_head(cb);
648 limit = gru_get_amo_value_limit(cb);
649
650 qlines = mqd->qlines;
651 half = (limit != qlines);
652
653 if (half)
654 mqh = gru_mesq_head(qlines / 2 + 1, qlines);
655 else
656 mqh = gru_mesq_head(2, qlines / 2 + 1);
657
658 /* Try to get lock for switching head pointer */
659 gru_gamir(cb, EOP_IR_CLR, HSTATUS(mqd->mq_gpa, half), XTYPE_DW, IMA);
660 if (gru_wait(cb) != CBS_IDLE)
661 goto cberr;
662 if (!gru_get_amo_value(cb)) {
663 STAT(mesq_qf_locked);
664 return MQE_QUEUE_FULL;
665 }
666
667 /* Got the lock. Send optional NOP if queue not full, */
668 if (head != limit) {
669 if (send_noop_message(cb, mqd, mesg)) {
670 gru_gamir(cb, EOP_IR_INC, HSTATUS(mqd->mq_gpa, half),
671 XTYPE_DW, IMA);
672 if (gru_wait(cb) != CBS_IDLE)
673 goto cberr;
674 STAT(mesq_qf_noop_not_full);
675 return MQIE_AGAIN;
676 }
677 avalue++;
678 }
679
680 /* Then flip queuehead to other half of queue. */
681 gru_gamer(cb, EOP_ERR_CSWAP, mqd->mq_gpa, XTYPE_DW, mqh.val, avalue,
682 IMA);
683 if (gru_wait(cb) != CBS_IDLE)
684 goto cberr;
685
686 /* If not successfully in swapping queue head, clear the hstatus lock */
687 if (gru_get_amo_value(cb) != avalue) {
688 STAT(mesq_qf_switch_head_failed);
689 gru_gamir(cb, EOP_IR_INC, HSTATUS(mqd->mq_gpa, half), XTYPE_DW,
690 IMA);
691 if (gru_wait(cb) != CBS_IDLE)
692 goto cberr;
693 }
694 return MQIE_AGAIN;
695cberr:
696 STAT(mesq_qf_unexpected_error);
697 return MQE_UNEXPECTED_CB_ERR;
698}
699
700/*
701 * Handle a PUT failure. Note: if message was a 2-line message, one of the
702 * lines might have successfully have been written. Before sending the
703 * message, "present" must be cleared in BOTH lines to prevent the receiver
704 * from prematurely seeing the full message.
705 */
706static int send_message_put_nacked(void *cb, struct gru_message_queue_desc *mqd,
707 void *mesg, int lines)
708{
709 unsigned long m;
710 int ret, loops = 200; /* experimentally determined */
711
712 m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
713 if (lines == 2) {
714 gru_vset(cb, m, 0, XTYPE_CL, lines, 1, IMA);
715 if (gru_wait(cb) != CBS_IDLE)
716 return MQE_UNEXPECTED_CB_ERR;
717 }
718 gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, lines, 1, IMA);
719 if (gru_wait(cb) != CBS_IDLE)
720 return MQE_UNEXPECTED_CB_ERR;
721
722 if (!mqd->interrupt_vector)
723 return MQE_OK;
724
725 /*
726 * Send a noop message in order to deliver a cross-partition interrupt
727 * to the SSI that contains the target message queue. Normally, the
728 * interrupt is automatically delivered by hardware following mesq
729 * operations, but some error conditions require explicit delivery.
730 * The noop message will trigger delivery. Otherwise partition failures
731 * could cause unrecovered errors.
732 */
733 do {
734 ret = send_noop_message(cb, mqd, mesg);
735 } while ((ret == MQIE_AGAIN || ret == MQE_CONGESTION) && (loops-- > 0));
736
737 if (ret == MQIE_AGAIN || ret == MQE_CONGESTION) {
738 /*
739 * Don't indicate to the app to resend the message, as it's
740 * already been successfully sent. We simply send an OK
741 * (rather than fail the send with MQE_UNEXPECTED_CB_ERR),
742 * assuming that the other side is receiving enough
743 * interrupts to get this message processed anyway.
744 */
745 ret = MQE_OK;
746 }
747 return ret;
748}
749
750/*
751 * Handle a gru_mesq failure. Some of these failures are software recoverable
752 * or retryable.
753 */
754static int send_message_failure(void *cb, struct gru_message_queue_desc *mqd,
755 void *mesg, int lines)
756{
757 int substatus, ret = 0;
758
759 substatus = gru_get_cb_message_queue_substatus(cb);
760 switch (substatus) {
761 case CBSS_NO_ERROR:
762 STAT(mesq_send_unexpected_error);
763 ret = MQE_UNEXPECTED_CB_ERR;
764 break;
765 case CBSS_LB_OVERFLOWED:
766 STAT(mesq_send_lb_overflow);
767 ret = MQE_CONGESTION;
768 break;
769 case CBSS_QLIMIT_REACHED:
770 STAT(mesq_send_qlimit_reached);
771 ret = send_message_queue_full(cb, mqd, mesg, lines);
772 break;
773 case CBSS_AMO_NACKED:
774 STAT(mesq_send_amo_nacked);
775 ret = MQE_CONGESTION;
776 break;
777 case CBSS_PUT_NACKED:
778 STAT(mesq_send_put_nacked);
779 ret = send_message_put_nacked(cb, mqd, mesg, lines);
780 break;
781 case CBSS_PAGE_OVERFLOW:
782 STAT(mesq_page_overflow);
783 fallthrough;
784 default:
785 BUG();
786 }
787 return ret;
788}
789
790/*
791 * Send a message to a message queue
792 * mqd message queue descriptor
793 * mesg message. ust be vaddr within a GSEG
794 * bytes message size (<= 2 CL)
795 */
796int gru_send_message_gpa(struct gru_message_queue_desc *mqd, void *mesg,
797 unsigned int bytes)
798{
799 struct message_header *mhdr;
800 void *cb;
801 void *dsr;
802 int istatus, clines, ret;
803
804 STAT(mesq_send);
805 BUG_ON(bytes < sizeof(int) || bytes > 2 * GRU_CACHE_LINE_BYTES);
806
807 clines = DIV_ROUND_UP(bytes, GRU_CACHE_LINE_BYTES);
808 if (gru_get_cpu_resources(bytes, &cb, &dsr))
809 return MQE_BUG_NO_RESOURCES;
810 memcpy(dsr, mesg, bytes);
811 mhdr = dsr;
812 mhdr->present = MQS_FULL;
813 mhdr->lines = clines;
814 if (clines == 2) {
815 mhdr->present2 = get_present2(mhdr);
816 restore_present2(mhdr, MQS_FULL);
817 }
818
819 do {
820 ret = MQE_OK;
821 gru_mesq(cb, mqd->mq_gpa, gru_get_tri(mhdr), clines, IMA);
822 istatus = gru_wait(cb);
823 if (istatus != CBS_IDLE)
824 ret = send_message_failure(cb, mqd, dsr, clines);
825 } while (ret == MQIE_AGAIN);
826 gru_free_cpu_resources(cb, dsr);
827
828 if (ret)
829 STAT(mesq_send_failed);
830 return ret;
831}
832EXPORT_SYMBOL_GPL(gru_send_message_gpa);
833
834/*
835 * Advance the receive pointer for the queue to the next message.
836 */
837void gru_free_message(struct gru_message_queue_desc *mqd, void *mesg)
838{
839 struct message_queue *mq = mqd->mq;
840 struct message_header *mhdr = mq->next;
841 void *next, *pnext;
842 int half = -1;
843 int lines = mhdr->lines;
844
845 if (lines == 2)
846 restore_present2(mhdr, MQS_EMPTY);
847 mhdr->present = MQS_EMPTY;
848
849 pnext = mq->next;
850 next = pnext + GRU_CACHE_LINE_BYTES * lines;
851 if (next == mq->limit) {
852 next = mq->start;
853 half = 1;
854 } else if (pnext < mq->start2 && next >= mq->start2) {
855 half = 0;
856 }
857
858 if (half >= 0)
859 mq->hstatus[half] = 1;
860 mq->next = next;
861}
862EXPORT_SYMBOL_GPL(gru_free_message);
863
864/*
865 * Get next message from message queue. Return NULL if no message
866 * present. User must call next_message() to move to next message.
867 * rmq message queue
868 */
869void *gru_get_next_message(struct gru_message_queue_desc *mqd)
870{
871 struct message_queue *mq = mqd->mq;
872 struct message_header *mhdr = mq->next;
873 int present = mhdr->present;
874
875 /* skip NOOP messages */
876 while (present == MQS_NOOP) {
877 gru_free_message(mqd, mhdr);
878 mhdr = mq->next;
879 present = mhdr->present;
880 }
881
882 /* Wait for both halves of 2 line messages */
883 if (present == MQS_FULL && mhdr->lines == 2 &&
884 get_present2(mhdr) == MQS_EMPTY)
885 present = MQS_EMPTY;
886
887 if (!present) {
888 STAT(mesq_receive_none);
889 return NULL;
890 }
891
892 if (mhdr->lines == 2)
893 restore_present2(mhdr, mhdr->present2);
894
895 STAT(mesq_receive);
896 return mhdr;
897}
898EXPORT_SYMBOL_GPL(gru_get_next_message);
899
900/* ---------------------- GRU DATA COPY FUNCTIONS ---------------------------*/
901
902/*
903 * Load a DW from a global GPA. The GPA can be a memory or MMR address.
904 */
905int gru_read_gpa(unsigned long *value, unsigned long gpa)
906{
907 void *cb;
908 void *dsr;
909 int ret, iaa;
910
911 STAT(read_gpa);
912 if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr))
913 return MQE_BUG_NO_RESOURCES;
914 iaa = gpa >> 62;
915 gru_vload_phys(cb, gpa, gru_get_tri(dsr), iaa, IMA);
916 ret = gru_wait(cb);
917 if (ret == CBS_IDLE)
918 *value = *(unsigned long *)dsr;
919 gru_free_cpu_resources(cb, dsr);
920 return ret;
921}
922EXPORT_SYMBOL_GPL(gru_read_gpa);
923
924
925/*
926 * Copy a block of data using the GRU resources
927 */
928int gru_copy_gpa(unsigned long dest_gpa, unsigned long src_gpa,
929 unsigned int bytes)
930{
931 void *cb;
932 void *dsr;
933 int ret;
934
935 STAT(copy_gpa);
936 if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr))
937 return MQE_BUG_NO_RESOURCES;
938 gru_bcopy(cb, src_gpa, dest_gpa, gru_get_tri(dsr),
939 XTYPE_B, bytes, GRU_NUM_KERNEL_DSR_CL, IMA);
940 ret = gru_wait(cb);
941 gru_free_cpu_resources(cb, dsr);
942 return ret;
943}
944EXPORT_SYMBOL_GPL(gru_copy_gpa);
945
946/* ------------------- KERNEL QUICKTESTS RUN AT STARTUP ----------------*/
947/* Temp - will delete after we gain confidence in the GRU */
948
949static int quicktest0(unsigned long arg)
950{
951 unsigned long word0;
952 unsigned long word1;
953 void *cb;
954 void *dsr;
955 unsigned long *p;
956 int ret = -EIO;
957
958 if (gru_get_cpu_resources(GRU_CACHE_LINE_BYTES, &cb, &dsr))
959 return MQE_BUG_NO_RESOURCES;
960 p = dsr;
961 word0 = MAGIC;
962 word1 = 0;
963
964 gru_vload(cb, uv_gpa(&word0), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA);
965 if (gru_wait(cb) != CBS_IDLE) {
966 printk(KERN_DEBUG "GRU:%d quicktest0: CBR failure 1\n", smp_processor_id());
967 goto done;
968 }
969
970 if (*p != MAGIC) {
971 printk(KERN_DEBUG "GRU:%d quicktest0 bad magic 0x%lx\n", smp_processor_id(), *p);
972 goto done;
973 }
974 gru_vstore(cb, uv_gpa(&word1), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA);
975 if (gru_wait(cb) != CBS_IDLE) {
976 printk(KERN_DEBUG "GRU:%d quicktest0: CBR failure 2\n", smp_processor_id());
977 goto done;
978 }
979
980 if (word0 != word1 || word1 != MAGIC) {
981 printk(KERN_DEBUG
982 "GRU:%d quicktest0 err: found 0x%lx, expected 0x%lx\n",
983 smp_processor_id(), word1, MAGIC);
984 goto done;
985 }
986 ret = 0;
987
988done:
989 gru_free_cpu_resources(cb, dsr);
990 return ret;
991}
992
993#define ALIGNUP(p, q) ((void *)(((unsigned long)(p) + (q) - 1) & ~(q - 1)))
994
995static int quicktest1(unsigned long arg)
996{
997 struct gru_message_queue_desc mqd;
998 void *p, *mq;
999 int i, ret = -EIO;
1000 char mes[GRU_CACHE_LINE_BYTES], *m;
1001
1002 /* Need 1K cacheline aligned that does not cross page boundary */
1003 p = kmalloc(4096, 0);
1004 if (p == NULL)
1005 return -ENOMEM;
1006 mq = ALIGNUP(p, 1024);
1007 memset(mes, 0xee, sizeof(mes));
1008
1009 gru_create_message_queue(&mqd, mq, 8 * GRU_CACHE_LINE_BYTES, 0, 0, 0);
1010 for (i = 0; i < 6; i++) {
1011 mes[8] = i;
1012 do {
1013 ret = gru_send_message_gpa(&mqd, mes, sizeof(mes));
1014 } while (ret == MQE_CONGESTION);
1015 if (ret)
1016 break;
1017 }
1018 if (ret != MQE_QUEUE_FULL || i != 4) {
1019 printk(KERN_DEBUG "GRU:%d quicktest1: unexpected status %d, i %d\n",
1020 smp_processor_id(), ret, i);
1021 goto done;
1022 }
1023
1024 for (i = 0; i < 6; i++) {
1025 m = gru_get_next_message(&mqd);
1026 if (!m || m[8] != i)
1027 break;
1028 gru_free_message(&mqd, m);
1029 }
1030 if (i != 4) {
1031 printk(KERN_DEBUG "GRU:%d quicktest2: bad message, i %d, m %p, m8 %d\n",
1032 smp_processor_id(), i, m, m ? m[8] : -1);
1033 goto done;
1034 }
1035 ret = 0;
1036
1037done:
1038 kfree(p);
1039 return ret;
1040}
1041
1042static int quicktest2(unsigned long arg)
1043{
1044 static DECLARE_COMPLETION(cmp);
1045 unsigned long han;
1046 int blade_id = 0;
1047 int numcb = 4;
1048 int ret = 0;
1049 unsigned long *buf;
1050 void *cb0, *cb;
1051 struct gru_control_block_status *gen;
1052 int i, k, istatus, bytes;
1053
1054 bytes = numcb * 4 * 8;
1055 buf = kmalloc(bytes, GFP_KERNEL);
1056 if (!buf)
1057 return -ENOMEM;
1058
1059 ret = -EBUSY;
1060 han = gru_reserve_async_resources(blade_id, numcb, 0, &cmp);
1061 if (!han)
1062 goto done;
1063
1064 gru_lock_async_resource(han, &cb0, NULL);
1065 memset(buf, 0xee, bytes);
1066 for (i = 0; i < numcb; i++)
1067 gru_vset(cb0 + i * GRU_HANDLE_STRIDE, uv_gpa(&buf[i * 4]), 0,
1068 XTYPE_DW, 4, 1, IMA_INTERRUPT);
1069
1070 ret = 0;
1071 k = numcb;
1072 do {
1073 gru_wait_async_cbr(han);
1074 for (i = 0; i < numcb; i++) {
1075 cb = cb0 + i * GRU_HANDLE_STRIDE;
1076 istatus = gru_check_status(cb);
1077 if (istatus != CBS_ACTIVE && istatus != CBS_CALL_OS)
1078 break;
1079 }
1080 if (i == numcb)
1081 continue;
1082 if (istatus != CBS_IDLE) {
1083 printk(KERN_DEBUG "GRU:%d quicktest2: cb %d, exception\n", smp_processor_id(), i);
1084 ret = -EFAULT;
1085 } else if (buf[4 * i] || buf[4 * i + 1] || buf[4 * i + 2] ||
1086 buf[4 * i + 3]) {
1087 printk(KERN_DEBUG "GRU:%d quicktest2:cb %d, buf 0x%lx, 0x%lx, 0x%lx, 0x%lx\n",
1088 smp_processor_id(), i, buf[4 * i], buf[4 * i + 1], buf[4 * i + 2], buf[4 * i + 3]);
1089 ret = -EIO;
1090 }
1091 k--;
1092 gen = cb;
1093 gen->istatus = CBS_CALL_OS; /* don't handle this CBR again */
1094 } while (k);
1095 BUG_ON(cmp.done);
1096
1097 gru_unlock_async_resource(han);
1098 gru_release_async_resources(han);
1099done:
1100 kfree(buf);
1101 return ret;
1102}
1103
1104#define BUFSIZE 200
1105static int quicktest3(unsigned long arg)
1106{
1107 char buf1[BUFSIZE], buf2[BUFSIZE];
1108 int ret = 0;
1109
1110 memset(buf2, 0, sizeof(buf2));
1111 memset(buf1, get_cycles() & 255, sizeof(buf1));
1112 gru_copy_gpa(uv_gpa(buf2), uv_gpa(buf1), BUFSIZE);
1113 if (memcmp(buf1, buf2, BUFSIZE)) {
1114 printk(KERN_DEBUG "GRU:%d quicktest3 error\n", smp_processor_id());
1115 ret = -EIO;
1116 }
1117 return ret;
1118}
1119
1120/*
1121 * Debugging only. User hook for various kernel tests
1122 * of driver & gru.
1123 */
1124int gru_ktest(unsigned long arg)
1125{
1126 int ret = -EINVAL;
1127
1128 switch (arg & 0xff) {
1129 case 0:
1130 ret = quicktest0(arg);
1131 break;
1132 case 1:
1133 ret = quicktest1(arg);
1134 break;
1135 case 2:
1136 ret = quicktest2(arg);
1137 break;
1138 case 3:
1139 ret = quicktest3(arg);
1140 break;
1141 case 99:
1142 ret = gru_free_kernel_contexts();
1143 break;
1144 }
1145 return ret;
1146
1147}
1148
1149int gru_kservices_init(void)
1150{
1151 return 0;
1152}
1153
1154void gru_kservices_exit(void)
1155{
1156 if (gru_free_kernel_contexts())
1157 BUG();
1158}
1159