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 */ |
115 | struct 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 */ |
127 | struct { |
128 | char ; |
129 | char ; |
130 | char ; |
131 | char ; |
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 | */ |
140 | static 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(sem: &bs->bs_kgts_sema); |
148 | down_write(sem: &bs->bs_kgts_sema); |
149 | |
150 | if (!bs->bs_kgts) { |
151 | do { |
152 | bs->bs_kgts = gru_alloc_gts(NULL, cbr_au_count: 0, dsr_au_count: 0, tlb_preload_count: 0, options: 0, tsid: 0); |
153 | if (!IS_ERR(ptr: bs->bs_kgts)) |
154 | break; |
155 | msleep(msecs: 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(bid: 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(gts: kgts)) { |
170 | msleep(msecs: 1); |
171 | gru_steal_context(gts: kgts); |
172 | } |
173 | gru_load_context(gts: 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(base: vaddr, ctxnum, line: 0); |
178 | bs->kernel_dsr = get_gseg_base_address_ds(base: vaddr, ctxnum, line: 0); |
179 | } |
180 | downgrade_write(sem: &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 | */ |
187 | static 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(sem: &bs->bs_kgts_sema)) { |
200 | kgts = bs->bs_kgts; |
201 | if (kgts && kgts->ts_gru) |
202 | gru_unload_context(gts: kgts, savestate: 0); |
203 | bs->bs_kgts = NULL; |
204 | up_write(sem: &bs->bs_kgts_sema); |
205 | kfree(objp: kgts); |
206 | } else { |
207 | ret++; |
208 | } |
209 | } |
210 | return ret; |
211 | } |
212 | |
213 | /* |
214 | * Lock & load the kernel context for the specified blade. |
215 | */ |
216 | static 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); |
222 | again: |
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(sem: &bs->bs_kgts_sema); |
228 | if (blade_id < 0 && bid != uv_numa_blade_id()) { |
229 | up_read(sem: &bs->bs_kgts_sema); |
230 | goto again; |
231 | } |
232 | if (!bs->bs_kgts || !bs->bs_kgts->ts_gru) |
233 | gru_load_kernel_context(bs, blade_id: 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 | */ |
242 | static 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(sem: &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 | */ |
255 | static 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(blade_id: -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 | */ |
272 | static void gru_free_cpu_resources(void *cb, void *dsr) |
273 | { |
274 | gru_unlock_kernel_context(blade_id: 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 | */ |
290 | unsigned 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(sem: &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(gts: kgts, savestate: 0); |
312 | ret = ASYNC_BID_TO_HAN(blade_id); |
313 | |
314 | done: |
315 | up_write(sem: &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 | */ |
325 | void gru_release_async_resources(unsigned long han) |
326 | { |
327 | struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han); |
328 | |
329 | down_write(sem: &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(sem: &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 | */ |
342 | void 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 | */ |
359 | void 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(bid: 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 | */ |
379 | void 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 | /*----------------------------------------------------------------------*/ |
387 | int 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), ctxnum: cbrnum); |
414 | gru_flush_cache(p: 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(p: cbe); |
422 | return 0; |
423 | } |
424 | |
425 | static 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: &excdet); |
433 | snprintf(buf, size, |
434 | fmt: "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, fmt: "No exception" ); |
440 | } |
441 | return buf; |
442 | } |
443 | |
444 | static 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 | |
453 | static 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: &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(p: gen); |
472 | } |
473 | return CBS_EXCEPTION; |
474 | } |
475 | |
476 | int 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 | |
489 | int 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 | |
501 | static void gru_abort(int ret, void *cb, char *str) |
502 | { |
503 | char buf[GRU_EXC_STR_SIZE]; |
504 | |
505 | panic(fmt: "GRU FATAL ERROR: %s - %s\n" , str, |
506 | gru_get_cb_exception_detail_str(ret, cb, buf, size: sizeof(buf))); |
507 | } |
508 | |
509 | void 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, str: "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 | */ |
529 | static inline int get_present2(void *p) |
530 | { |
531 | struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES; |
532 | return mhdr->present; |
533 | } |
534 | |
535 | static 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 | */ |
545 | int 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(head: 2, limit: qlines / 2 + 1); |
561 | mqd->mq = mq; |
562 | mqd->mq_gpa = uv_gpa(v: 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 | } |
569 | EXPORT_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 | */ |
579 | static int send_noop_message(void *cb, struct gru_message_queue_desc *mqd, |
580 | void *mesg) |
581 | { |
582 | const struct message_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, queue: mqd->mq_gpa, tri0: gru_get_tri(vaddr: mhdr), nelem: 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, mem_addr: m, tri0: gru_get_tri(vaddr: mesg), XTYPE_CL, nelem: 1, stride: 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 | */ |
637 | static 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(head: qlines / 2 + 1, limit: qlines); |
655 | else |
656 | mqh = gru_mesq_head(head: 2, limit: 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, src: mqd->mq_gpa, XTYPE_DW, operand1: mqh.val, operand2: 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; |
695 | cberr: |
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 | */ |
706 | static 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, mem_addr: m, value: 0, XTYPE_CL, nelem: lines, stride: 1, IMA); |
715 | if (gru_wait(cb) != CBS_IDLE) |
716 | return MQE_UNEXPECTED_CB_ERR; |
717 | } |
718 | gru_vstore(cb, mem_addr: m, tri0: gru_get_tri(vaddr: mesg), XTYPE_CL, nelem: lines, stride: 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 | */ |
754 | static 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 | */ |
796 | int 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(dsr_bytes: bytes, cb: &cb, dsr: &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(p: mhdr); |
816 | restore_present2(p: mhdr, MQS_FULL); |
817 | } |
818 | |
819 | do { |
820 | ret = MQE_OK; |
821 | gru_mesq(cb, queue: mqd->mq_gpa, tri0: gru_get_tri(vaddr: mhdr), nelem: clines, IMA); |
822 | istatus = gru_wait(cb); |
823 | if (istatus != CBS_IDLE) |
824 | ret = send_message_failure(cb, mqd, mesg: dsr, lines: 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 | } |
832 | EXPORT_SYMBOL_GPL(gru_send_message_gpa); |
833 | |
834 | /* |
835 | * Advance the receive pointer for the queue to the next message. |
836 | */ |
837 | void 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(p: 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 | } |
862 | EXPORT_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 | */ |
869 | void *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(p: 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(p: mhdr, val: mhdr->present2); |
894 | |
895 | STAT(mesq_receive); |
896 | return mhdr; |
897 | } |
898 | EXPORT_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 | */ |
905 | int 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: &cb, dsr: &dsr)) |
913 | return MQE_BUG_NO_RESOURCES; |
914 | iaa = gpa >> 62; |
915 | gru_vload_phys(cb, gpa, tri0: gru_get_tri(vaddr: 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 | } |
922 | EXPORT_SYMBOL_GPL(gru_read_gpa); |
923 | |
924 | |
925 | /* |
926 | * Copy a block of data using the GRU resources |
927 | */ |
928 | int 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: &cb, dsr: &dsr)) |
937 | return MQE_BUG_NO_RESOURCES; |
938 | gru_bcopy(cb, src: src_gpa, dest: dest_gpa, tri0: gru_get_tri(vaddr: dsr), |
939 | XTYPE_B, nelem: bytes, GRU_NUM_KERNEL_DSR_CL, IMA); |
940 | ret = gru_wait(cb); |
941 | gru_free_cpu_resources(cb, dsr); |
942 | return ret; |
943 | } |
944 | EXPORT_SYMBOL_GPL(gru_copy_gpa); |
945 | |
946 | /* ------------------- KERNEL QUICKTESTS RUN AT STARTUP ----------------*/ |
947 | /* Temp - will delete after we gain confidence in the GRU */ |
948 | |
949 | static 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: &cb, dsr: &dsr)) |
959 | return MQE_BUG_NO_RESOURCES; |
960 | p = dsr; |
961 | word0 = MAGIC; |
962 | word1 = 0; |
963 | |
964 | gru_vload(cb, mem_addr: uv_gpa(v: &word0), tri0: gru_get_tri(vaddr: dsr), XTYPE_DW, nelem: 1, stride: 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, mem_addr: uv_gpa(v: &word1), tri0: gru_get_tri(vaddr: dsr), XTYPE_DW, nelem: 1, stride: 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 | |
988 | done: |
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 | |
995 | static 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(size: 4096, flags: 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 | |
1037 | done: |
1038 | kfree(objp: p); |
1039 | return ret; |
1040 | } |
1041 | |
1042 | static 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(size: bytes, GFP_KERNEL); |
1056 | if (!buf) |
1057 | return -ENOMEM; |
1058 | |
1059 | ret = -EBUSY; |
1060 | han = gru_reserve_async_resources(blade_id, cbrs: numcb, dsr_bytes: 0, cmp: &cmp); |
1061 | if (!han) |
1062 | goto done; |
1063 | |
1064 | gru_lock_async_resource(han, cb: &cb0, NULL); |
1065 | memset(buf, 0xee, bytes); |
1066 | for (i = 0; i < numcb; i++) |
1067 | gru_vset(cb: cb0 + i * GRU_HANDLE_STRIDE, mem_addr: uv_gpa(v: &buf[i * 4]), value: 0, |
1068 | XTYPE_DW, nelem: 4, stride: 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); |
1099 | done: |
1100 | kfree(objp: buf); |
1101 | return ret; |
1102 | } |
1103 | |
1104 | #define BUFSIZE 200 |
1105 | static 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(v: buf2), uv_gpa(v: buf1), BUFSIZE); |
1113 | if (memcmp(p: buf1, q: 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 | */ |
1124 | int 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 | |
1149 | int gru_kservices_init(void) |
1150 | { |
1151 | return 0; |
1152 | } |
1153 | |
1154 | void gru_kservices_exit(void) |
1155 | { |
1156 | if (gru_free_kernel_contexts()) |
1157 | BUG(); |
1158 | } |
1159 | |
1160 | |