1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (c) 2000-2007 Silicon Graphics, Inc.  All Rights Reserved.
7  */
8 
9 #include <linux/module.h>
10 #include <asm/sn/nodepda.h>
11 #include <asm/sn/addrs.h>
12 #include <asm/sn/arch.h>
13 #include <asm/sn/sn_cpuid.h>
14 #include <asm/sn/pda.h>
15 #include <asm/sn/shubio.h>
16 #include <asm/nodedata.h>
17 #include <asm/delay.h>
18 
19 #include <linux/bootmem.h>
20 #include <linux/string.h>
21 #include <linux/sched.h>
22 #include <linux/slab.h>
23 
24 #include <asm/sn/bte.h>
25 
26 #ifndef L1_CACHE_MASK
27 #define L1_CACHE_MASK (L1_CACHE_BYTES - 1)
28 #endif
29 
30 /* two interfaces on two btes */
31 #define MAX_INTERFACES_TO_TRY		4
32 #define MAX_NODES_TO_TRY		2
33 
bte_if_on_node(nasid_t nasid,int interface)34 static struct bteinfo_s *bte_if_on_node(nasid_t nasid, int interface)
35 {
36 	nodepda_t *tmp_nodepda;
37 
38 	if (nasid_to_cnodeid(nasid) == -1)
39 		return (struct bteinfo_s *)NULL;
40 
41 	tmp_nodepda = NODEPDA(nasid_to_cnodeid(nasid));
42 	return &tmp_nodepda->bte_if[interface];
43 
44 }
45 
bte_start_transfer(struct bteinfo_s * bte,u64 len,u64 mode)46 static inline void bte_start_transfer(struct bteinfo_s *bte, u64 len, u64 mode)
47 {
48 	if (is_shub2()) {
49 		BTE_CTRL_STORE(bte, (IBLS_BUSY | ((len) | (mode) << 24)));
50 	} else {
51 		BTE_LNSTAT_STORE(bte, len);
52 		BTE_CTRL_STORE(bte, mode);
53 	}
54 }
55 
56 /************************************************************************
57  * Block Transfer Engine copy related functions.
58  *
59  ***********************************************************************/
60 
61 /*
62  * bte_copy(src, dest, len, mode, notification)
63  *
64  * Use the block transfer engine to move kernel memory from src to dest
65  * using the assigned mode.
66  *
67  * Parameters:
68  *   src - physical address of the transfer source.
69  *   dest - physical address of the transfer destination.
70  *   len - number of bytes to transfer from source to dest.
71  *   mode - hardware defined.  See reference information
72  *          for IBCT0/1 in the SHUB Programmers Reference
73  *   notification - kernel virtual address of the notification cache
74  *                  line.  If NULL, the default is used and
75  *                  the bte_copy is synchronous.
76  *
77  * NOTE:  This function requires src, dest, and len to
78  * be cacheline aligned.
79  */
bte_copy(u64 src,u64 dest,u64 len,u64 mode,void * notification)80 bte_result_t bte_copy(u64 src, u64 dest, u64 len, u64 mode, void *notification)
81 {
82 	u64 transfer_size;
83 	u64 transfer_stat;
84 	u64 notif_phys_addr;
85 	struct bteinfo_s *bte;
86 	bte_result_t bte_status;
87 	unsigned long irq_flags;
88 	unsigned long itc_end = 0;
89 	int nasid_to_try[MAX_NODES_TO_TRY];
90 	int my_nasid = cpuid_to_nasid(raw_smp_processor_id());
91 	int bte_if_index, nasid_index;
92 	int bte_first, btes_per_node = BTES_PER_NODE;
93 
94 	BTE_PRINTK(("bte_copy(0x%lx, 0x%lx, 0x%lx, 0x%lx, 0x%p)\n",
95 		    src, dest, len, mode, notification));
96 
97 	if (len == 0) {
98 		return BTE_SUCCESS;
99 	}
100 
101 	BUG_ON(len & L1_CACHE_MASK);
102 	BUG_ON(src & L1_CACHE_MASK);
103 	BUG_ON(dest & L1_CACHE_MASK);
104 	BUG_ON(len > BTE_MAX_XFER);
105 
106 	/*
107 	 * Start with interface corresponding to cpu number
108 	 */
109 	bte_first = raw_smp_processor_id() % btes_per_node;
110 
111 	if (mode & BTE_USE_DEST) {
112 		/* try remote then local */
113 		nasid_to_try[0] = NASID_GET(dest);
114 		if (mode & BTE_USE_ANY) {
115 			nasid_to_try[1] = my_nasid;
116 		} else {
117 			nasid_to_try[1] = (int)NULL;
118 		}
119 	} else {
120 		/* try local then remote */
121 		nasid_to_try[0] = my_nasid;
122 		if (mode & BTE_USE_ANY) {
123 			nasid_to_try[1] = NASID_GET(dest);
124 		} else {
125 			nasid_to_try[1] = (int)NULL;
126 		}
127 	}
128 
129 retry_bteop:
130 	do {
131 		local_irq_save(irq_flags);
132 
133 		bte_if_index = bte_first;
134 		nasid_index = 0;
135 
136 		/* Attempt to lock one of the BTE interfaces. */
137 		while (nasid_index < MAX_NODES_TO_TRY) {
138 			bte = bte_if_on_node(nasid_to_try[nasid_index],bte_if_index);
139 
140 			if (bte == NULL) {
141 				nasid_index++;
142 				continue;
143 			}
144 
145 			if (spin_trylock(&bte->spinlock)) {
146 				if (!(*bte->most_rcnt_na & BTE_WORD_AVAILABLE) ||
147 				    (BTE_LNSTAT_LOAD(bte) & BTE_ACTIVE)) {
148 					/* Got the lock but BTE still busy */
149 					spin_unlock(&bte->spinlock);
150 				} else {
151 					/* we got the lock and it's not busy */
152 					break;
153 				}
154 			}
155 
156 			bte_if_index = (bte_if_index + 1) % btes_per_node; /* Next interface */
157 			if (bte_if_index == bte_first) {
158 				/*
159 				 * We've tried all interfaces on this node
160 				 */
161 				nasid_index++;
162 			}
163 
164 			bte = NULL;
165 		}
166 
167 		if (bte != NULL) {
168 			break;
169 		}
170 
171 		local_irq_restore(irq_flags);
172 
173 		if (!(mode & BTE_WACQUIRE)) {
174 			return BTEFAIL_NOTAVAIL;
175 		}
176 	} while (1);
177 
178 	if (notification == NULL) {
179 		/* User does not want to be notified. */
180 		bte->most_rcnt_na = &bte->notify;
181 	} else {
182 		bte->most_rcnt_na = notification;
183 	}
184 
185 	/* Calculate the number of cache lines to transfer. */
186 	transfer_size = ((len >> L1_CACHE_SHIFT) & BTE_LEN_MASK);
187 
188 	/* Initialize the notification to a known value. */
189 	*bte->most_rcnt_na = BTE_WORD_BUSY;
190 	notif_phys_addr = (u64)bte->most_rcnt_na;
191 
192 	/* Set the source and destination registers */
193 	BTE_PRINTKV(("IBSA = 0x%lx)\n", src));
194 	BTE_SRC_STORE(bte, src);
195 	BTE_PRINTKV(("IBDA = 0x%lx)\n", dest));
196 	BTE_DEST_STORE(bte, dest);
197 
198 	/* Set the notification register */
199 	BTE_PRINTKV(("IBNA = 0x%lx)\n", notif_phys_addr));
200 	BTE_NOTIF_STORE(bte, notif_phys_addr);
201 
202 	/* Initiate the transfer */
203 	BTE_PRINTK(("IBCT = 0x%lx)\n", BTE_VALID_MODE(mode)));
204 	bte_start_transfer(bte, transfer_size, BTE_VALID_MODE(mode));
205 
206 	itc_end = ia64_get_itc() + (40000000 * local_cpu_data->cyc_per_usec);
207 
208 	spin_unlock_irqrestore(&bte->spinlock, irq_flags);
209 
210 	if (notification != NULL) {
211 		return BTE_SUCCESS;
212 	}
213 
214 	while ((transfer_stat = *bte->most_rcnt_na) == BTE_WORD_BUSY) {
215 		cpu_relax();
216 		if (ia64_get_itc() > itc_end) {
217 			BTE_PRINTK(("BTE timeout nasid 0x%x bte%d IBLS = 0x%lx na 0x%lx\n",
218 				NASID_GET(bte->bte_base_addr), bte->bte_num,
219 				BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na) );
220 			bte->bte_error_count++;
221 			bte->bh_error = IBLS_ERROR;
222 			bte_error_handler((unsigned long)NODEPDA(bte->bte_cnode));
223 			*bte->most_rcnt_na = BTE_WORD_AVAILABLE;
224 			goto retry_bteop;
225 		}
226 	}
227 
228 	BTE_PRINTKV((" Delay Done.  IBLS = 0x%lx, most_rcnt_na = 0x%lx\n",
229 		     BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na));
230 
231 	if (transfer_stat & IBLS_ERROR) {
232 		bte_status = BTE_GET_ERROR_STATUS(transfer_stat);
233 	} else {
234 		bte_status = BTE_SUCCESS;
235 	}
236 	*bte->most_rcnt_na = BTE_WORD_AVAILABLE;
237 
238 	BTE_PRINTK(("Returning status is 0x%lx and most_rcnt_na is 0x%lx\n",
239 		    BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na));
240 
241 	return bte_status;
242 }
243 
244 EXPORT_SYMBOL(bte_copy);
245 
246 /*
247  * bte_unaligned_copy(src, dest, len, mode)
248  *
249  * use the block transfer engine to move kernel
250  * memory from src to dest using the assigned mode.
251  *
252  * Parameters:
253  *   src - physical address of the transfer source.
254  *   dest - physical address of the transfer destination.
255  *   len - number of bytes to transfer from source to dest.
256  *   mode - hardware defined.  See reference information
257  *          for IBCT0/1 in the SGI documentation.
258  *
259  * NOTE: If the source, dest, and len are all cache line aligned,
260  * then it would be _FAR_ preferable to use bte_copy instead.
261  */
bte_unaligned_copy(u64 src,u64 dest,u64 len,u64 mode)262 bte_result_t bte_unaligned_copy(u64 src, u64 dest, u64 len, u64 mode)
263 {
264 	int destFirstCacheOffset;
265 	u64 headBteSource;
266 	u64 headBteLen;
267 	u64 headBcopySrcOffset;
268 	u64 headBcopyDest;
269 	u64 headBcopyLen;
270 	u64 footBteSource;
271 	u64 footBteLen;
272 	u64 footBcopyDest;
273 	u64 footBcopyLen;
274 	bte_result_t rv;
275 	char *bteBlock, *bteBlock_unaligned;
276 
277 	if (len == 0) {
278 		return BTE_SUCCESS;
279 	}
280 
281 	/* temporary buffer used during unaligned transfers */
282 	bteBlock_unaligned = kmalloc(len + 3 * L1_CACHE_BYTES, GFP_KERNEL);
283 	if (bteBlock_unaligned == NULL) {
284 		return BTEFAIL_NOTAVAIL;
285 	}
286 	bteBlock = (char *)L1_CACHE_ALIGN((u64) bteBlock_unaligned);
287 
288 	headBcopySrcOffset = src & L1_CACHE_MASK;
289 	destFirstCacheOffset = dest & L1_CACHE_MASK;
290 
291 	/*
292 	 * At this point, the transfer is broken into
293 	 * (up to) three sections.  The first section is
294 	 * from the start address to the first physical
295 	 * cache line, the second is from the first physical
296 	 * cache line to the last complete cache line,
297 	 * and the third is from the last cache line to the
298 	 * end of the buffer.  The first and third sections
299 	 * are handled by bte copying into a temporary buffer
300 	 * and then bcopy'ing the necessary section into the
301 	 * final location.  The middle section is handled with
302 	 * a standard bte copy.
303 	 *
304 	 * One nasty exception to the above rule is when the
305 	 * source and destination are not symmetrically
306 	 * mis-aligned.  If the source offset from the first
307 	 * cache line is different from the destination offset,
308 	 * we make the first section be the entire transfer
309 	 * and the bcopy the entire block into place.
310 	 */
311 	if (headBcopySrcOffset == destFirstCacheOffset) {
312 
313 		/*
314 		 * Both the source and destination are the same
315 		 * distance from a cache line boundary so we can
316 		 * use the bte to transfer the bulk of the
317 		 * data.
318 		 */
319 		headBteSource = src & ~L1_CACHE_MASK;
320 		headBcopyDest = dest;
321 		if (headBcopySrcOffset) {
322 			headBcopyLen =
323 			    (len >
324 			     (L1_CACHE_BYTES -
325 			      headBcopySrcOffset) ? L1_CACHE_BYTES
326 			     - headBcopySrcOffset : len);
327 			headBteLen = L1_CACHE_BYTES;
328 		} else {
329 			headBcopyLen = 0;
330 			headBteLen = 0;
331 		}
332 
333 		if (len > headBcopyLen) {
334 			footBcopyLen = (len - headBcopyLen) & L1_CACHE_MASK;
335 			footBteLen = L1_CACHE_BYTES;
336 
337 			footBteSource = src + len - footBcopyLen;
338 			footBcopyDest = dest + len - footBcopyLen;
339 
340 			if (footBcopyDest == (headBcopyDest + headBcopyLen)) {
341 				/*
342 				 * We have two contiguous bcopy
343 				 * blocks.  Merge them.
344 				 */
345 				headBcopyLen += footBcopyLen;
346 				headBteLen += footBteLen;
347 			} else if (footBcopyLen > 0) {
348 				rv = bte_copy(footBteSource,
349 					      ia64_tpa((unsigned long)bteBlock),
350 					      footBteLen, mode, NULL);
351 				if (rv != BTE_SUCCESS) {
352 					kfree(bteBlock_unaligned);
353 					return rv;
354 				}
355 
356 				memcpy(__va(footBcopyDest),
357 				       (char *)bteBlock, footBcopyLen);
358 			}
359 		} else {
360 			footBcopyLen = 0;
361 			footBteLen = 0;
362 		}
363 
364 		if (len > (headBcopyLen + footBcopyLen)) {
365 			/* now transfer the middle. */
366 			rv = bte_copy((src + headBcopyLen),
367 				      (dest +
368 				       headBcopyLen),
369 				      (len - headBcopyLen -
370 				       footBcopyLen), mode, NULL);
371 			if (rv != BTE_SUCCESS) {
372 				kfree(bteBlock_unaligned);
373 				return rv;
374 			}
375 
376 		}
377 	} else {
378 
379 		/*
380 		 * The transfer is not symmetric, we will
381 		 * allocate a buffer large enough for all the
382 		 * data, bte_copy into that buffer and then
383 		 * bcopy to the destination.
384 		 */
385 
386 		headBcopySrcOffset = src & L1_CACHE_MASK;
387 		headBcopyDest = dest;
388 		headBcopyLen = len;
389 
390 		headBteSource = src - headBcopySrcOffset;
391 		/* Add the leading and trailing bytes from source */
392 		headBteLen = L1_CACHE_ALIGN(len + headBcopySrcOffset);
393 	}
394 
395 	if (headBcopyLen > 0) {
396 		rv = bte_copy(headBteSource,
397 			      ia64_tpa((unsigned long)bteBlock), headBteLen,
398 			      mode, NULL);
399 		if (rv != BTE_SUCCESS) {
400 			kfree(bteBlock_unaligned);
401 			return rv;
402 		}
403 
404 		memcpy(__va(headBcopyDest), ((char *)bteBlock +
405 					     headBcopySrcOffset), headBcopyLen);
406 	}
407 	kfree(bteBlock_unaligned);
408 	return BTE_SUCCESS;
409 }
410 
411 EXPORT_SYMBOL(bte_unaligned_copy);
412 
413 /************************************************************************
414  * Block Transfer Engine initialization functions.
415  *
416  ***********************************************************************/
417 
418 /*
419  * bte_init_node(nodepda, cnode)
420  *
421  * Initialize the nodepda structure with BTE base addresses and
422  * spinlocks.
423  */
bte_init_node(nodepda_t * mynodepda,cnodeid_t cnode)424 void bte_init_node(nodepda_t * mynodepda, cnodeid_t cnode)
425 {
426 	int i;
427 
428 	/*
429 	 * Indicate that all the block transfer engines on this node
430 	 * are available.
431 	 */
432 
433 	/*
434 	 * Allocate one bte_recover_t structure per node.  It holds
435 	 * the recovery lock for node.  All the bte interface structures
436 	 * will point at this one bte_recover structure to get the lock.
437 	 */
438 	spin_lock_init(&mynodepda->bte_recovery_lock);
439 	init_timer(&mynodepda->bte_recovery_timer);
440 	mynodepda->bte_recovery_timer.function = bte_error_handler;
441 	mynodepda->bte_recovery_timer.data = (unsigned long)mynodepda;
442 
443 	for (i = 0; i < BTES_PER_NODE; i++) {
444 		u64 *base_addr;
445 
446 		/* Which link status register should we use? */
447 		base_addr = (u64 *)
448 		    REMOTE_HUB_ADDR(cnodeid_to_nasid(cnode), BTE_BASE_ADDR(i));
449 		mynodepda->bte_if[i].bte_base_addr = base_addr;
450 		mynodepda->bte_if[i].bte_source_addr = BTE_SOURCE_ADDR(base_addr);
451 		mynodepda->bte_if[i].bte_destination_addr = BTE_DEST_ADDR(base_addr);
452 		mynodepda->bte_if[i].bte_control_addr = BTE_CTRL_ADDR(base_addr);
453 		mynodepda->bte_if[i].bte_notify_addr = BTE_NOTIF_ADDR(base_addr);
454 
455 		/*
456 		 * Initialize the notification and spinlock
457 		 * so the first transfer can occur.
458 		 */
459 		mynodepda->bte_if[i].most_rcnt_na =
460 		    &(mynodepda->bte_if[i].notify);
461 		mynodepda->bte_if[i].notify = BTE_WORD_AVAILABLE;
462 		spin_lock_init(&mynodepda->bte_if[i].spinlock);
463 
464 		mynodepda->bte_if[i].bte_cnode = cnode;
465 		mynodepda->bte_if[i].bte_error_count = 0;
466 		mynodepda->bte_if[i].bte_num = i;
467 		mynodepda->bte_if[i].cleanup_active = 0;
468 		mynodepda->bte_if[i].bh_error = 0;
469 	}
470 
471 }
472