1 /*
2  * pSeries_lpar.c
3  * Copyright (C) 2001 Todd Inglett, IBM Corporation
4  *
5  * pSeries LPAR support.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
20  */
21 
22 /* Enables debugging of low-level hash table routines - careful! */
23 #undef DEBUG
24 
25 #include <linux/kernel.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/console.h>
28 #include <linux/export.h>
29 #include <asm/processor.h>
30 #include <asm/mmu.h>
31 #include <asm/page.h>
32 #include <asm/pgtable.h>
33 #include <asm/machdep.h>
34 #include <asm/mmu_context.h>
35 #include <asm/iommu.h>
36 #include <asm/tlbflush.h>
37 #include <asm/tlb.h>
38 #include <asm/prom.h>
39 #include <asm/cputable.h>
40 #include <asm/udbg.h>
41 #include <asm/smp.h>
42 #include <asm/trace.h>
43 #include <asm/firmware.h>
44 #include <asm/plpar_wrappers.h>
45 
46 #include "pseries.h"
47 
48 /* Flag bits for H_BULK_REMOVE */
49 #define HBR_REQUEST	0x4000000000000000UL
50 #define HBR_RESPONSE	0x8000000000000000UL
51 #define HBR_END		0xc000000000000000UL
52 #define HBR_AVPN	0x0200000000000000UL
53 #define HBR_ANDCOND	0x0100000000000000UL
54 
55 
56 /* in hvCall.S */
57 EXPORT_SYMBOL(plpar_hcall);
58 EXPORT_SYMBOL(plpar_hcall9);
59 EXPORT_SYMBOL(plpar_hcall_norets);
60 
61 extern void pSeries_find_serial_port(void);
62 
63 void vpa_init(int cpu)
64 {
65 	int hwcpu = get_hard_smp_processor_id(cpu);
66 	unsigned long addr;
67 	long ret;
68 	struct paca_struct *pp;
69 	struct dtl_entry *dtl;
70 
71 	/*
72 	 * The spec says it "may be problematic" if CPU x registers the VPA of
73 	 * CPU y. We should never do that, but wail if we ever do.
74 	 */
75 	WARN_ON(cpu != smp_processor_id());
76 
77 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
78 		lppaca_of(cpu).vmxregs_in_use = 1;
79 
80 	if (cpu_has_feature(CPU_FTR_ARCH_207S))
81 		lppaca_of(cpu).ebb_regs_in_use = 1;
82 
83 	addr = __pa(&lppaca_of(cpu));
84 	ret = register_vpa(hwcpu, addr);
85 
86 	if (ret) {
87 		pr_err("WARNING: VPA registration for cpu %d (hw %d) of area "
88 		       "%lx failed with %ld\n", cpu, hwcpu, addr, ret);
89 		return;
90 	}
91 	/*
92 	 * PAPR says this feature is SLB-Buffer but firmware never
93 	 * reports that.  All SPLPAR support SLB shadow buffer.
94 	 */
95 	addr = __pa(paca[cpu].slb_shadow_ptr);
96 	if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
97 		ret = register_slb_shadow(hwcpu, addr);
98 		if (ret)
99 			pr_err("WARNING: SLB shadow buffer registration for "
100 			       "cpu %d (hw %d) of area %lx failed with %ld\n",
101 			       cpu, hwcpu, addr, ret);
102 	}
103 
104 	/*
105 	 * Register dispatch trace log, if one has been allocated.
106 	 */
107 	pp = &paca[cpu];
108 	dtl = pp->dispatch_log;
109 	if (dtl) {
110 		pp->dtl_ridx = 0;
111 		pp->dtl_curr = dtl;
112 		lppaca_of(cpu).dtl_idx = 0;
113 
114 		/* hypervisor reads buffer length from this field */
115 		dtl->enqueue_to_dispatch_time = cpu_to_be32(DISPATCH_LOG_BYTES);
116 		ret = register_dtl(hwcpu, __pa(dtl));
117 		if (ret)
118 			pr_err("WARNING: DTL registration of cpu %d (hw %d) "
119 			       "failed with %ld\n", smp_processor_id(),
120 			       hwcpu, ret);
121 		lppaca_of(cpu).dtl_enable_mask = 2;
122 	}
123 }
124 
125 static long pSeries_lpar_hpte_insert(unsigned long hpte_group,
126 				     unsigned long vpn, unsigned long pa,
127 				     unsigned long rflags, unsigned long vflags,
128 				     int psize, int apsize, int ssize)
129 {
130 	unsigned long lpar_rc;
131 	unsigned long flags;
132 	unsigned long slot;
133 	unsigned long hpte_v, hpte_r;
134 
135 	if (!(vflags & HPTE_V_BOLTED))
136 		pr_devel("hpte_insert(group=%lx, vpn=%016lx, "
137 			 "pa=%016lx, rflags=%lx, vflags=%lx, psize=%d)\n",
138 			 hpte_group, vpn,  pa, rflags, vflags, psize);
139 
140 	hpte_v = hpte_encode_v(vpn, psize, apsize, ssize) | vflags | HPTE_V_VALID;
141 	hpte_r = hpte_encode_r(pa, psize, apsize) | rflags;
142 
143 	if (!(vflags & HPTE_V_BOLTED))
144 		pr_devel(" hpte_v=%016lx, hpte_r=%016lx\n", hpte_v, hpte_r);
145 
146 	/* Now fill in the actual HPTE */
147 	/* Set CEC cookie to 0         */
148 	/* Zero page = 0               */
149 	/* I-cache Invalidate = 0      */
150 	/* I-cache synchronize = 0     */
151 	/* Exact = 0                   */
152 	flags = 0;
153 
154 	/* Make pHyp happy */
155 	if ((rflags & _PAGE_NO_CACHE) && !(rflags & _PAGE_WRITETHRU))
156 		hpte_r &= ~HPTE_R_M;
157 
158 	if (firmware_has_feature(FW_FEATURE_XCMO) && !(hpte_r & HPTE_R_N))
159 		flags |= H_COALESCE_CAND;
160 
161 	lpar_rc = plpar_pte_enter(flags, hpte_group, hpte_v, hpte_r, &slot);
162 	if (unlikely(lpar_rc == H_PTEG_FULL)) {
163 		if (!(vflags & HPTE_V_BOLTED))
164 			pr_devel(" full\n");
165 		return -1;
166 	}
167 
168 	/*
169 	 * Since we try and ioremap PHBs we don't own, the pte insert
170 	 * will fail. However we must catch the failure in hash_page
171 	 * or we will loop forever, so return -2 in this case.
172 	 */
173 	if (unlikely(lpar_rc != H_SUCCESS)) {
174 		if (!(vflags & HPTE_V_BOLTED))
175 			pr_devel(" lpar err %ld\n", lpar_rc);
176 		return -2;
177 	}
178 	if (!(vflags & HPTE_V_BOLTED))
179 		pr_devel(" -> slot: %lu\n", slot & 7);
180 
181 	/* Because of iSeries, we have to pass down the secondary
182 	 * bucket bit here as well
183 	 */
184 	return (slot & 7) | (!!(vflags & HPTE_V_SECONDARY) << 3);
185 }
186 
187 static DEFINE_SPINLOCK(pSeries_lpar_tlbie_lock);
188 
189 static long pSeries_lpar_hpte_remove(unsigned long hpte_group)
190 {
191 	unsigned long slot_offset;
192 	unsigned long lpar_rc;
193 	int i;
194 	unsigned long dummy1, dummy2;
195 
196 	/* pick a random slot to start at */
197 	slot_offset = mftb() & 0x7;
198 
199 	for (i = 0; i < HPTES_PER_GROUP; i++) {
200 
201 		/* don't remove a bolted entry */
202 		lpar_rc = plpar_pte_remove(H_ANDCOND, hpte_group + slot_offset,
203 					   (0x1UL << 4), &dummy1, &dummy2);
204 		if (lpar_rc == H_SUCCESS)
205 			return i;
206 
207 		/*
208 		 * The test for adjunct partition is performed before the
209 		 * ANDCOND test.  H_RESOURCE may be returned, so we need to
210 		 * check for that as well.
211 		 */
212 		BUG_ON(lpar_rc != H_NOT_FOUND && lpar_rc != H_RESOURCE);
213 
214 		slot_offset++;
215 		slot_offset &= 0x7;
216 	}
217 
218 	return -1;
219 }
220 
221 static void pSeries_lpar_hptab_clear(void)
222 {
223 	unsigned long size_bytes = 1UL << ppc64_pft_size;
224 	unsigned long hpte_count = size_bytes >> 4;
225 	struct {
226 		unsigned long pteh;
227 		unsigned long ptel;
228 	} ptes[4];
229 	long lpar_rc;
230 	unsigned long i, j;
231 
232 	/* Read in batches of 4,
233 	 * invalidate only valid entries not in the VRMA
234 	 * hpte_count will be a multiple of 4
235          */
236 	for (i = 0; i < hpte_count; i += 4) {
237 		lpar_rc = plpar_pte_read_4_raw(0, i, (void *)ptes);
238 		if (lpar_rc != H_SUCCESS)
239 			continue;
240 		for (j = 0; j < 4; j++){
241 			if ((ptes[j].pteh & HPTE_V_VRMA_MASK) ==
242 				HPTE_V_VRMA_MASK)
243 				continue;
244 			if (ptes[j].pteh & HPTE_V_VALID)
245 				plpar_pte_remove_raw(0, i + j, 0,
246 					&(ptes[j].pteh), &(ptes[j].ptel));
247 		}
248 	}
249 
250 #ifdef __LITTLE_ENDIAN__
251 	/* Reset exceptions to big endian */
252 	if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
253 		long rc;
254 
255 		rc = pseries_big_endian_exceptions();
256 		/*
257 		 * At this point it is unlikely panic() will get anything
258 		 * out to the user, but at least this will stop us from
259 		 * continuing on further and creating an even more
260 		 * difficult to debug situation.
261 		 */
262 		if (rc)
263 			panic("Could not enable big endian exceptions");
264 	}
265 #endif
266 }
267 
268 /*
269  * NOTE: for updatepp ops we are fortunate that the linux "newpp" bits and
270  * the low 3 bits of flags happen to line up.  So no transform is needed.
271  * We can probably optimize here and assume the high bits of newpp are
272  * already zero.  For now I am paranoid.
273  */
274 static long pSeries_lpar_hpte_updatepp(unsigned long slot,
275 				       unsigned long newpp,
276 				       unsigned long vpn,
277 				       int psize, int apsize,
278 				       int ssize, int local)
279 {
280 	unsigned long lpar_rc;
281 	unsigned long flags = (newpp & 7) | H_AVPN;
282 	unsigned long want_v;
283 
284 	want_v = hpte_encode_avpn(vpn, psize, ssize);
285 
286 	pr_devel("    update: avpnv=%016lx, hash=%016lx, f=%lx, psize: %d ...",
287 		 want_v, slot, flags, psize);
288 
289 	lpar_rc = plpar_pte_protect(flags, slot, want_v);
290 
291 	if (lpar_rc == H_NOT_FOUND) {
292 		pr_devel("not found !\n");
293 		return -1;
294 	}
295 
296 	pr_devel("ok\n");
297 
298 	BUG_ON(lpar_rc != H_SUCCESS);
299 
300 	return 0;
301 }
302 
303 static unsigned long pSeries_lpar_hpte_getword0(unsigned long slot)
304 {
305 	unsigned long dword0;
306 	unsigned long lpar_rc;
307 	unsigned long dummy_word1;
308 	unsigned long flags;
309 
310 	/* Read 1 pte at a time                        */
311 	/* Do not need RPN to logical page translation */
312 	/* No cross CEC PFT access                     */
313 	flags = 0;
314 
315 	lpar_rc = plpar_pte_read(flags, slot, &dword0, &dummy_word1);
316 
317 	BUG_ON(lpar_rc != H_SUCCESS);
318 
319 	return dword0;
320 }
321 
322 static long pSeries_lpar_hpte_find(unsigned long vpn, int psize, int ssize)
323 {
324 	unsigned long hash;
325 	unsigned long i;
326 	long slot;
327 	unsigned long want_v, hpte_v;
328 
329 	hash = hpt_hash(vpn, mmu_psize_defs[psize].shift, ssize);
330 	want_v = hpte_encode_avpn(vpn, psize, ssize);
331 
332 	/* Bolted entries are always in the primary group */
333 	slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
334 	for (i = 0; i < HPTES_PER_GROUP; i++) {
335 		hpte_v = pSeries_lpar_hpte_getword0(slot);
336 
337 		if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID))
338 			/* HPTE matches */
339 			return slot;
340 		++slot;
341 	}
342 
343 	return -1;
344 }
345 
346 static void pSeries_lpar_hpte_updateboltedpp(unsigned long newpp,
347 					     unsigned long ea,
348 					     int psize, int ssize)
349 {
350 	unsigned long vpn;
351 	unsigned long lpar_rc, slot, vsid, flags;
352 
353 	vsid = get_kernel_vsid(ea, ssize);
354 	vpn = hpt_vpn(ea, vsid, ssize);
355 
356 	slot = pSeries_lpar_hpte_find(vpn, psize, ssize);
357 	BUG_ON(slot == -1);
358 
359 	flags = newpp & 7;
360 	lpar_rc = plpar_pte_protect(flags, slot, 0);
361 
362 	BUG_ON(lpar_rc != H_SUCCESS);
363 }
364 
365 static void pSeries_lpar_hpte_invalidate(unsigned long slot, unsigned long vpn,
366 					 int psize, int apsize,
367 					 int ssize, int local)
368 {
369 	unsigned long want_v;
370 	unsigned long lpar_rc;
371 	unsigned long dummy1, dummy2;
372 
373 	pr_devel("    inval : slot=%lx, vpn=%016lx, psize: %d, local: %d\n",
374 		 slot, vpn, psize, local);
375 
376 	want_v = hpte_encode_avpn(vpn, psize, ssize);
377 	lpar_rc = plpar_pte_remove(H_AVPN, slot, want_v, &dummy1, &dummy2);
378 	if (lpar_rc == H_NOT_FOUND)
379 		return;
380 
381 	BUG_ON(lpar_rc != H_SUCCESS);
382 }
383 
384 /*
385  * Limit iterations holding pSeries_lpar_tlbie_lock to 3. We also need
386  * to make sure that we avoid bouncing the hypervisor tlbie lock.
387  */
388 #define PPC64_HUGE_HPTE_BATCH 12
389 
390 static void __pSeries_lpar_hugepage_invalidate(unsigned long *slot,
391 					     unsigned long *vpn, int count,
392 					     int psize, int ssize)
393 {
394 	unsigned long param[8];
395 	int i = 0, pix = 0, rc;
396 	unsigned long flags = 0;
397 	int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
398 
399 	if (lock_tlbie)
400 		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
401 
402 	for (i = 0; i < count; i++) {
403 
404 		if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
405 			pSeries_lpar_hpte_invalidate(slot[i], vpn[i], psize, 0,
406 						     ssize, 0);
407 		} else {
408 			param[pix] = HBR_REQUEST | HBR_AVPN | slot[i];
409 			param[pix+1] = hpte_encode_avpn(vpn[i], psize, ssize);
410 			pix += 2;
411 			if (pix == 8) {
412 				rc = plpar_hcall9(H_BULK_REMOVE, param,
413 						  param[0], param[1], param[2],
414 						  param[3], param[4], param[5],
415 						  param[6], param[7]);
416 				BUG_ON(rc != H_SUCCESS);
417 				pix = 0;
418 			}
419 		}
420 	}
421 	if (pix) {
422 		param[pix] = HBR_END;
423 		rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
424 				  param[2], param[3], param[4], param[5],
425 				  param[6], param[7]);
426 		BUG_ON(rc != H_SUCCESS);
427 	}
428 
429 	if (lock_tlbie)
430 		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
431 }
432 
433 static void pSeries_lpar_hugepage_invalidate(struct mm_struct *mm,
434 				       unsigned char *hpte_slot_array,
435 				       unsigned long addr, int psize)
436 {
437 	int ssize = 0, i, index = 0;
438 	unsigned long s_addr = addr;
439 	unsigned int max_hpte_count, valid;
440 	unsigned long vpn_array[PPC64_HUGE_HPTE_BATCH];
441 	unsigned long slot_array[PPC64_HUGE_HPTE_BATCH];
442 	unsigned long shift, hidx, vpn = 0, vsid, hash, slot;
443 
444 	shift = mmu_psize_defs[psize].shift;
445 	max_hpte_count = 1U << (PMD_SHIFT - shift);
446 
447 	for (i = 0; i < max_hpte_count; i++) {
448 		valid = hpte_valid(hpte_slot_array, i);
449 		if (!valid)
450 			continue;
451 		hidx =  hpte_hash_index(hpte_slot_array, i);
452 
453 		/* get the vpn */
454 		addr = s_addr + (i * (1ul << shift));
455 		if (!is_kernel_addr(addr)) {
456 			ssize = user_segment_size(addr);
457 			vsid = get_vsid(mm->context.id, addr, ssize);
458 			WARN_ON(vsid == 0);
459 		} else {
460 			vsid = get_kernel_vsid(addr, mmu_kernel_ssize);
461 			ssize = mmu_kernel_ssize;
462 		}
463 
464 		vpn = hpt_vpn(addr, vsid, ssize);
465 		hash = hpt_hash(vpn, shift, ssize);
466 		if (hidx & _PTEIDX_SECONDARY)
467 			hash = ~hash;
468 
469 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
470 		slot += hidx & _PTEIDX_GROUP_IX;
471 
472 		slot_array[index] = slot;
473 		vpn_array[index] = vpn;
474 		if (index == PPC64_HUGE_HPTE_BATCH - 1) {
475 			/*
476 			 * Now do a bluk invalidate
477 			 */
478 			__pSeries_lpar_hugepage_invalidate(slot_array,
479 							   vpn_array,
480 							   PPC64_HUGE_HPTE_BATCH,
481 							   psize, ssize);
482 			index = 0;
483 		} else
484 			index++;
485 	}
486 	if (index)
487 		__pSeries_lpar_hugepage_invalidate(slot_array, vpn_array,
488 						   index, psize, ssize);
489 }
490 
491 static void pSeries_lpar_hpte_removebolted(unsigned long ea,
492 					   int psize, int ssize)
493 {
494 	unsigned long vpn;
495 	unsigned long slot, vsid;
496 
497 	vsid = get_kernel_vsid(ea, ssize);
498 	vpn = hpt_vpn(ea, vsid, ssize);
499 
500 	slot = pSeries_lpar_hpte_find(vpn, psize, ssize);
501 	BUG_ON(slot == -1);
502 	/*
503 	 * lpar doesn't use the passed actual page size
504 	 */
505 	pSeries_lpar_hpte_invalidate(slot, vpn, psize, 0, ssize, 0);
506 }
507 
508 /*
509  * Take a spinlock around flushes to avoid bouncing the hypervisor tlbie
510  * lock.
511  */
512 static void pSeries_lpar_flush_hash_range(unsigned long number, int local)
513 {
514 	unsigned long vpn;
515 	unsigned long i, pix, rc;
516 	unsigned long flags = 0;
517 	struct ppc64_tlb_batch *batch = &__get_cpu_var(ppc64_tlb_batch);
518 	int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
519 	unsigned long param[9];
520 	unsigned long hash, index, shift, hidx, slot;
521 	real_pte_t pte;
522 	int psize, ssize;
523 
524 	if (lock_tlbie)
525 		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
526 
527 	psize = batch->psize;
528 	ssize = batch->ssize;
529 	pix = 0;
530 	for (i = 0; i < number; i++) {
531 		vpn = batch->vpn[i];
532 		pte = batch->pte[i];
533 		pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) {
534 			hash = hpt_hash(vpn, shift, ssize);
535 			hidx = __rpte_to_hidx(pte, index);
536 			if (hidx & _PTEIDX_SECONDARY)
537 				hash = ~hash;
538 			slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
539 			slot += hidx & _PTEIDX_GROUP_IX;
540 			if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
541 				/*
542 				 * lpar doesn't use the passed actual page size
543 				 */
544 				pSeries_lpar_hpte_invalidate(slot, vpn, psize,
545 							     0, ssize, local);
546 			} else {
547 				param[pix] = HBR_REQUEST | HBR_AVPN | slot;
548 				param[pix+1] = hpte_encode_avpn(vpn, psize,
549 								ssize);
550 				pix += 2;
551 				if (pix == 8) {
552 					rc = plpar_hcall9(H_BULK_REMOVE, param,
553 						param[0], param[1], param[2],
554 						param[3], param[4], param[5],
555 						param[6], param[7]);
556 					BUG_ON(rc != H_SUCCESS);
557 					pix = 0;
558 				}
559 			}
560 		} pte_iterate_hashed_end();
561 	}
562 	if (pix) {
563 		param[pix] = HBR_END;
564 		rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
565 				  param[2], param[3], param[4], param[5],
566 				  param[6], param[7]);
567 		BUG_ON(rc != H_SUCCESS);
568 	}
569 
570 	if (lock_tlbie)
571 		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
572 }
573 
574 static int __init disable_bulk_remove(char *str)
575 {
576 	if (strcmp(str, "off") == 0 &&
577 	    firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
578 			printk(KERN_INFO "Disabling BULK_REMOVE firmware feature");
579 			powerpc_firmware_features &= ~FW_FEATURE_BULK_REMOVE;
580 	}
581 	return 1;
582 }
583 
584 __setup("bulk_remove=", disable_bulk_remove);
585 
586 void __init hpte_init_lpar(void)
587 {
588 	ppc_md.hpte_invalidate	= pSeries_lpar_hpte_invalidate;
589 	ppc_md.hpte_updatepp	= pSeries_lpar_hpte_updatepp;
590 	ppc_md.hpte_updateboltedpp = pSeries_lpar_hpte_updateboltedpp;
591 	ppc_md.hpte_insert	= pSeries_lpar_hpte_insert;
592 	ppc_md.hpte_remove	= pSeries_lpar_hpte_remove;
593 	ppc_md.hpte_removebolted = pSeries_lpar_hpte_removebolted;
594 	ppc_md.flush_hash_range	= pSeries_lpar_flush_hash_range;
595 	ppc_md.hpte_clear_all   = pSeries_lpar_hptab_clear;
596 	ppc_md.hugepage_invalidate = pSeries_lpar_hugepage_invalidate;
597 }
598 
599 #ifdef CONFIG_PPC_SMLPAR
600 #define CMO_FREE_HINT_DEFAULT 1
601 static int cmo_free_hint_flag = CMO_FREE_HINT_DEFAULT;
602 
603 static int __init cmo_free_hint(char *str)
604 {
605 	char *parm;
606 	parm = strstrip(str);
607 
608 	if (strcasecmp(parm, "no") == 0 || strcasecmp(parm, "off") == 0) {
609 		printk(KERN_INFO "cmo_free_hint: CMO free page hinting is not active.\n");
610 		cmo_free_hint_flag = 0;
611 		return 1;
612 	}
613 
614 	cmo_free_hint_flag = 1;
615 	printk(KERN_INFO "cmo_free_hint: CMO free page hinting is active.\n");
616 
617 	if (strcasecmp(parm, "yes") == 0 || strcasecmp(parm, "on") == 0)
618 		return 1;
619 
620 	return 0;
621 }
622 
623 __setup("cmo_free_hint=", cmo_free_hint);
624 
625 static void pSeries_set_page_state(struct page *page, int order,
626 				   unsigned long state)
627 {
628 	int i, j;
629 	unsigned long cmo_page_sz, addr;
630 
631 	cmo_page_sz = cmo_get_page_size();
632 	addr = __pa((unsigned long)page_address(page));
633 
634 	for (i = 0; i < (1 << order); i++, addr += PAGE_SIZE) {
635 		for (j = 0; j < PAGE_SIZE; j += cmo_page_sz)
636 			plpar_hcall_norets(H_PAGE_INIT, state, addr + j, 0);
637 	}
638 }
639 
640 void arch_free_page(struct page *page, int order)
641 {
642 	if (!cmo_free_hint_flag || !firmware_has_feature(FW_FEATURE_CMO))
643 		return;
644 
645 	pSeries_set_page_state(page, order, H_PAGE_SET_UNUSED);
646 }
647 EXPORT_SYMBOL(arch_free_page);
648 
649 #endif
650 
651 #ifdef CONFIG_TRACEPOINTS
652 /*
653  * We optimise our hcall path by placing hcall_tracepoint_refcount
654  * directly in the TOC so we can check if the hcall tracepoints are
655  * enabled via a single load.
656  */
657 
658 /* NB: reg/unreg are called while guarded with the tracepoints_mutex */
659 extern long hcall_tracepoint_refcount;
660 
661 /*
662  * Since the tracing code might execute hcalls we need to guard against
663  * recursion. One example of this are spinlocks calling H_YIELD on
664  * shared processor partitions.
665  */
666 static DEFINE_PER_CPU(unsigned int, hcall_trace_depth);
667 
668 void hcall_tracepoint_regfunc(void)
669 {
670 	hcall_tracepoint_refcount++;
671 }
672 
673 void hcall_tracepoint_unregfunc(void)
674 {
675 	hcall_tracepoint_refcount--;
676 }
677 
678 void __trace_hcall_entry(unsigned long opcode, unsigned long *args)
679 {
680 	unsigned long flags;
681 	unsigned int *depth;
682 
683 	/*
684 	 * We cannot call tracepoints inside RCU idle regions which
685 	 * means we must not trace H_CEDE.
686 	 */
687 	if (opcode == H_CEDE)
688 		return;
689 
690 	local_irq_save(flags);
691 
692 	depth = &__get_cpu_var(hcall_trace_depth);
693 
694 	if (*depth)
695 		goto out;
696 
697 	(*depth)++;
698 	preempt_disable();
699 	trace_hcall_entry(opcode, args);
700 	(*depth)--;
701 
702 out:
703 	local_irq_restore(flags);
704 }
705 
706 void __trace_hcall_exit(long opcode, unsigned long retval,
707 			unsigned long *retbuf)
708 {
709 	unsigned long flags;
710 	unsigned int *depth;
711 
712 	if (opcode == H_CEDE)
713 		return;
714 
715 	local_irq_save(flags);
716 
717 	depth = &__get_cpu_var(hcall_trace_depth);
718 
719 	if (*depth)
720 		goto out;
721 
722 	(*depth)++;
723 	trace_hcall_exit(opcode, retval, retbuf);
724 	preempt_enable();
725 	(*depth)--;
726 
727 out:
728 	local_irq_restore(flags);
729 }
730 #endif
731 
732 /**
733  * h_get_mpp
734  * H_GET_MPP hcall returns info in 7 parms
735  */
736 int h_get_mpp(struct hvcall_mpp_data *mpp_data)
737 {
738 	int rc;
739 	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
740 
741 	rc = plpar_hcall9(H_GET_MPP, retbuf);
742 
743 	mpp_data->entitled_mem = retbuf[0];
744 	mpp_data->mapped_mem = retbuf[1];
745 
746 	mpp_data->group_num = (retbuf[2] >> 2 * 8) & 0xffff;
747 	mpp_data->pool_num = retbuf[2] & 0xffff;
748 
749 	mpp_data->mem_weight = (retbuf[3] >> 7 * 8) & 0xff;
750 	mpp_data->unallocated_mem_weight = (retbuf[3] >> 6 * 8) & 0xff;
751 	mpp_data->unallocated_entitlement = retbuf[3] & 0xffffffffffffUL;
752 
753 	mpp_data->pool_size = retbuf[4];
754 	mpp_data->loan_request = retbuf[5];
755 	mpp_data->backing_mem = retbuf[6];
756 
757 	return rc;
758 }
759 EXPORT_SYMBOL(h_get_mpp);
760 
761 int h_get_mpp_x(struct hvcall_mpp_x_data *mpp_x_data)
762 {
763 	int rc;
764 	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE] = { 0 };
765 
766 	rc = plpar_hcall9(H_GET_MPP_X, retbuf);
767 
768 	mpp_x_data->coalesced_bytes = retbuf[0];
769 	mpp_x_data->pool_coalesced_bytes = retbuf[1];
770 	mpp_x_data->pool_purr_cycles = retbuf[2];
771 	mpp_x_data->pool_spurr_cycles = retbuf[3];
772 
773 	return rc;
774 }
775