xref: /openbmc/linux/arch/powerpc/platforms/pseries/lpar.c (revision cc1adb5f32557f10f48e8febbef7278a2db9d593)
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 <linux/static_key.h>
30 #include <asm/processor.h>
31 #include <asm/mmu.h>
32 #include <asm/page.h>
33 #include <asm/pgtable.h>
34 #include <asm/machdep.h>
35 #include <asm/mmu_context.h>
36 #include <asm/iommu.h>
37 #include <asm/tlbflush.h>
38 #include <asm/tlb.h>
39 #include <asm/prom.h>
40 #include <asm/cputable.h>
41 #include <asm/udbg.h>
42 #include <asm/smp.h>
43 #include <asm/trace.h>
44 #include <asm/firmware.h>
45 #include <asm/plpar_wrappers.h>
46 
47 #include "pseries.h"
48 
49 /* Flag bits for H_BULK_REMOVE */
50 #define HBR_REQUEST	0x4000000000000000UL
51 #define HBR_RESPONSE	0x8000000000000000UL
52 #define HBR_END		0xc000000000000000UL
53 #define HBR_AVPN	0x0200000000000000UL
54 #define HBR_ANDCOND	0x0100000000000000UL
55 
56 
57 /* in hvCall.S */
58 EXPORT_SYMBOL(plpar_hcall);
59 EXPORT_SYMBOL(plpar_hcall9);
60 EXPORT_SYMBOL(plpar_hcall_norets);
61 
62 extern void pSeries_find_serial_port(void);
63 
64 void vpa_init(int cpu)
65 {
66 	int hwcpu = get_hard_smp_processor_id(cpu);
67 	unsigned long addr;
68 	long ret;
69 	struct paca_struct *pp;
70 	struct dtl_entry *dtl;
71 
72 	/*
73 	 * The spec says it "may be problematic" if CPU x registers the VPA of
74 	 * CPU y. We should never do that, but wail if we ever do.
75 	 */
76 	WARN_ON(cpu != smp_processor_id());
77 
78 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
79 		lppaca_of(cpu).vmxregs_in_use = 1;
80 
81 	if (cpu_has_feature(CPU_FTR_ARCH_207S))
82 		lppaca_of(cpu).ebb_regs_in_use = 1;
83 
84 	addr = __pa(&lppaca_of(cpu));
85 	ret = register_vpa(hwcpu, addr);
86 
87 	if (ret) {
88 		pr_err("WARNING: VPA registration for cpu %d (hw %d) of area "
89 		       "%lx failed with %ld\n", cpu, hwcpu, addr, ret);
90 		return;
91 	}
92 	/*
93 	 * PAPR says this feature is SLB-Buffer but firmware never
94 	 * reports that.  All SPLPAR support SLB shadow buffer.
95 	 */
96 	addr = __pa(paca[cpu].slb_shadow_ptr);
97 	if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
98 		ret = register_slb_shadow(hwcpu, addr);
99 		if (ret)
100 			pr_err("WARNING: SLB shadow buffer registration for "
101 			       "cpu %d (hw %d) of area %lx failed with %ld\n",
102 			       cpu, hwcpu, addr, ret);
103 	}
104 
105 	/*
106 	 * Register dispatch trace log, if one has been allocated.
107 	 */
108 	pp = &paca[cpu];
109 	dtl = pp->dispatch_log;
110 	if (dtl) {
111 		pp->dtl_ridx = 0;
112 		pp->dtl_curr = dtl;
113 		lppaca_of(cpu).dtl_idx = 0;
114 
115 		/* hypervisor reads buffer length from this field */
116 		dtl->enqueue_to_dispatch_time = cpu_to_be32(DISPATCH_LOG_BYTES);
117 		ret = register_dtl(hwcpu, __pa(dtl));
118 		if (ret)
119 			pr_err("WARNING: DTL registration of cpu %d (hw %d) "
120 			       "failed with %ld\n", smp_processor_id(),
121 			       hwcpu, ret);
122 		lppaca_of(cpu).dtl_enable_mask = 2;
123 	}
124 }
125 
126 static long pSeries_lpar_hpte_insert(unsigned long hpte_group,
127 				     unsigned long vpn, unsigned long pa,
128 				     unsigned long rflags, unsigned long vflags,
129 				     int psize, int apsize, int ssize)
130 {
131 	unsigned long lpar_rc;
132 	unsigned long flags;
133 	unsigned long slot;
134 	unsigned long hpte_v, hpte_r;
135 
136 	if (!(vflags & HPTE_V_BOLTED))
137 		pr_devel("hpte_insert(group=%lx, vpn=%016lx, "
138 			 "pa=%016lx, rflags=%lx, vflags=%lx, psize=%d)\n",
139 			 hpte_group, vpn,  pa, rflags, vflags, psize);
140 
141 	hpte_v = hpte_encode_v(vpn, psize, apsize, ssize) | vflags | HPTE_V_VALID;
142 	hpte_r = hpte_encode_r(pa, psize, apsize) | rflags;
143 
144 	if (!(vflags & HPTE_V_BOLTED))
145 		pr_devel(" hpte_v=%016lx, hpte_r=%016lx\n", hpte_v, hpte_r);
146 
147 	/* Now fill in the actual HPTE */
148 	/* Set CEC cookie to 0         */
149 	/* Zero page = 0               */
150 	/* I-cache Invalidate = 0      */
151 	/* I-cache synchronize = 0     */
152 	/* Exact = 0                   */
153 	flags = 0;
154 
155 	/* Make pHyp happy */
156 	if ((rflags & _PAGE_NO_CACHE) && !(rflags & _PAGE_WRITETHRU))
157 		hpte_r &= ~HPTE_R_M;
158 
159 	if (firmware_has_feature(FW_FEATURE_XCMO) && !(hpte_r & HPTE_R_N))
160 		flags |= H_COALESCE_CAND;
161 
162 	lpar_rc = plpar_pte_enter(flags, hpte_group, hpte_v, hpte_r, &slot);
163 	if (unlikely(lpar_rc == H_PTEG_FULL)) {
164 		if (!(vflags & HPTE_V_BOLTED))
165 			pr_devel(" full\n");
166 		return -1;
167 	}
168 
169 	/*
170 	 * Since we try and ioremap PHBs we don't own, the pte insert
171 	 * will fail. However we must catch the failure in hash_page
172 	 * or we will loop forever, so return -2 in this case.
173 	 */
174 	if (unlikely(lpar_rc != H_SUCCESS)) {
175 		if (!(vflags & HPTE_V_BOLTED))
176 			pr_devel(" lpar err %ld\n", lpar_rc);
177 		return -2;
178 	}
179 	if (!(vflags & HPTE_V_BOLTED))
180 		pr_devel(" -> slot: %lu\n", slot & 7);
181 
182 	/* Because of iSeries, we have to pass down the secondary
183 	 * bucket bit here as well
184 	 */
185 	return (slot & 7) | (!!(vflags & HPTE_V_SECONDARY) << 3);
186 }
187 
188 static DEFINE_SPINLOCK(pSeries_lpar_tlbie_lock);
189 
190 static long pSeries_lpar_hpte_remove(unsigned long hpte_group)
191 {
192 	unsigned long slot_offset;
193 	unsigned long lpar_rc;
194 	int i;
195 	unsigned long dummy1, dummy2;
196 
197 	/* pick a random slot to start at */
198 	slot_offset = mftb() & 0x7;
199 
200 	for (i = 0; i < HPTES_PER_GROUP; i++) {
201 
202 		/* don't remove a bolted entry */
203 		lpar_rc = plpar_pte_remove(H_ANDCOND, hpte_group + slot_offset,
204 					   (0x1UL << 4), &dummy1, &dummy2);
205 		if (lpar_rc == H_SUCCESS)
206 			return i;
207 
208 		/*
209 		 * The test for adjunct partition is performed before the
210 		 * ANDCOND test.  H_RESOURCE may be returned, so we need to
211 		 * check for that as well.
212 		 */
213 		BUG_ON(lpar_rc != H_NOT_FOUND && lpar_rc != H_RESOURCE);
214 
215 		slot_offset++;
216 		slot_offset &= 0x7;
217 	}
218 
219 	return -1;
220 }
221 
222 static void pSeries_lpar_hptab_clear(void)
223 {
224 	unsigned long size_bytes = 1UL << ppc64_pft_size;
225 	unsigned long hpte_count = size_bytes >> 4;
226 	struct {
227 		unsigned long pteh;
228 		unsigned long ptel;
229 	} ptes[4];
230 	long lpar_rc;
231 	unsigned long i, j;
232 
233 	/* Read in batches of 4,
234 	 * invalidate only valid entries not in the VRMA
235 	 * hpte_count will be a multiple of 4
236          */
237 	for (i = 0; i < hpte_count; i += 4) {
238 		lpar_rc = plpar_pte_read_4_raw(0, i, (void *)ptes);
239 		if (lpar_rc != H_SUCCESS)
240 			continue;
241 		for (j = 0; j < 4; j++){
242 			if ((ptes[j].pteh & HPTE_V_VRMA_MASK) ==
243 				HPTE_V_VRMA_MASK)
244 				continue;
245 			if (ptes[j].pteh & HPTE_V_VALID)
246 				plpar_pte_remove_raw(0, i + j, 0,
247 					&(ptes[j].pteh), &(ptes[j].ptel));
248 		}
249 	}
250 
251 #ifdef __LITTLE_ENDIAN__
252 	/* Reset exceptions to big endian */
253 	if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
254 		long rc;
255 
256 		rc = pseries_big_endian_exceptions();
257 		/*
258 		 * At this point it is unlikely panic() will get anything
259 		 * out to the user, but at least this will stop us from
260 		 * continuing on further and creating an even more
261 		 * difficult to debug situation.
262 		 */
263 		if (rc)
264 			panic("Could not enable big endian exceptions");
265 	}
266 #endif
267 }
268 
269 /*
270  * NOTE: for updatepp ops we are fortunate that the linux "newpp" bits and
271  * the low 3 bits of flags happen to line up.  So no transform is needed.
272  * We can probably optimize here and assume the high bits of newpp are
273  * already zero.  For now I am paranoid.
274  */
275 static long pSeries_lpar_hpte_updatepp(unsigned long slot,
276 				       unsigned long newpp,
277 				       unsigned long vpn,
278 				       int psize, int apsize,
279 				       int ssize, int local)
280 {
281 	unsigned long lpar_rc;
282 	unsigned long flags = (newpp & 7) | H_AVPN;
283 	unsigned long want_v;
284 
285 	want_v = hpte_encode_avpn(vpn, psize, ssize);
286 
287 	pr_devel("    update: avpnv=%016lx, hash=%016lx, f=%lx, psize: %d ...",
288 		 want_v, slot, flags, psize);
289 
290 	lpar_rc = plpar_pte_protect(flags, slot, want_v);
291 
292 	if (lpar_rc == H_NOT_FOUND) {
293 		pr_devel("not found !\n");
294 		return -1;
295 	}
296 
297 	pr_devel("ok\n");
298 
299 	BUG_ON(lpar_rc != H_SUCCESS);
300 
301 	return 0;
302 }
303 
304 static unsigned long pSeries_lpar_hpte_getword0(unsigned long slot)
305 {
306 	unsigned long dword0;
307 	unsigned long lpar_rc;
308 	unsigned long dummy_word1;
309 	unsigned long flags;
310 
311 	/* Read 1 pte at a time                        */
312 	/* Do not need RPN to logical page translation */
313 	/* No cross CEC PFT access                     */
314 	flags = 0;
315 
316 	lpar_rc = plpar_pte_read(flags, slot, &dword0, &dummy_word1);
317 
318 	BUG_ON(lpar_rc != H_SUCCESS);
319 
320 	return dword0;
321 }
322 
323 static long pSeries_lpar_hpte_find(unsigned long vpn, int psize, int ssize)
324 {
325 	unsigned long hash;
326 	unsigned long i;
327 	long slot;
328 	unsigned long want_v, hpte_v;
329 
330 	hash = hpt_hash(vpn, mmu_psize_defs[psize].shift, ssize);
331 	want_v = hpte_encode_avpn(vpn, psize, ssize);
332 
333 	/* Bolted entries are always in the primary group */
334 	slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
335 	for (i = 0; i < HPTES_PER_GROUP; i++) {
336 		hpte_v = pSeries_lpar_hpte_getword0(slot);
337 
338 		if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID))
339 			/* HPTE matches */
340 			return slot;
341 		++slot;
342 	}
343 
344 	return -1;
345 }
346 
347 static void pSeries_lpar_hpte_updateboltedpp(unsigned long newpp,
348 					     unsigned long ea,
349 					     int psize, int ssize)
350 {
351 	unsigned long vpn;
352 	unsigned long lpar_rc, slot, vsid, flags;
353 
354 	vsid = get_kernel_vsid(ea, ssize);
355 	vpn = hpt_vpn(ea, vsid, ssize);
356 
357 	slot = pSeries_lpar_hpte_find(vpn, psize, ssize);
358 	BUG_ON(slot == -1);
359 
360 	flags = newpp & 7;
361 	lpar_rc = plpar_pte_protect(flags, slot, 0);
362 
363 	BUG_ON(lpar_rc != H_SUCCESS);
364 }
365 
366 static void pSeries_lpar_hpte_invalidate(unsigned long slot, unsigned long vpn,
367 					 int psize, int apsize,
368 					 int ssize, int local)
369 {
370 	unsigned long want_v;
371 	unsigned long lpar_rc;
372 	unsigned long dummy1, dummy2;
373 
374 	pr_devel("    inval : slot=%lx, vpn=%016lx, psize: %d, local: %d\n",
375 		 slot, vpn, psize, local);
376 
377 	want_v = hpte_encode_avpn(vpn, psize, ssize);
378 	lpar_rc = plpar_pte_remove(H_AVPN, slot, want_v, &dummy1, &dummy2);
379 	if (lpar_rc == H_NOT_FOUND)
380 		return;
381 
382 	BUG_ON(lpar_rc != H_SUCCESS);
383 }
384 
385 /*
386  * Limit iterations holding pSeries_lpar_tlbie_lock to 3. We also need
387  * to make sure that we avoid bouncing the hypervisor tlbie lock.
388  */
389 #define PPC64_HUGE_HPTE_BATCH 12
390 
391 static void __pSeries_lpar_hugepage_invalidate(unsigned long *slot,
392 					     unsigned long *vpn, int count,
393 					     int psize, int ssize)
394 {
395 	unsigned long param[8];
396 	int i = 0, pix = 0, rc;
397 	unsigned long flags = 0;
398 	int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
399 
400 	if (lock_tlbie)
401 		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
402 
403 	for (i = 0; i < count; i++) {
404 
405 		if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
406 			pSeries_lpar_hpte_invalidate(slot[i], vpn[i], psize, 0,
407 						     ssize, 0);
408 		} else {
409 			param[pix] = HBR_REQUEST | HBR_AVPN | slot[i];
410 			param[pix+1] = hpte_encode_avpn(vpn[i], psize, ssize);
411 			pix += 2;
412 			if (pix == 8) {
413 				rc = plpar_hcall9(H_BULK_REMOVE, param,
414 						  param[0], param[1], param[2],
415 						  param[3], param[4], param[5],
416 						  param[6], param[7]);
417 				BUG_ON(rc != H_SUCCESS);
418 				pix = 0;
419 			}
420 		}
421 	}
422 	if (pix) {
423 		param[pix] = HBR_END;
424 		rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
425 				  param[2], param[3], param[4], param[5],
426 				  param[6], param[7]);
427 		BUG_ON(rc != H_SUCCESS);
428 	}
429 
430 	if (lock_tlbie)
431 		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
432 }
433 
434 static void pSeries_lpar_hugepage_invalidate(struct mm_struct *mm,
435 				       unsigned char *hpte_slot_array,
436 				       unsigned long addr, int psize)
437 {
438 	int ssize = 0, i, index = 0;
439 	unsigned long s_addr = addr;
440 	unsigned int max_hpte_count, valid;
441 	unsigned long vpn_array[PPC64_HUGE_HPTE_BATCH];
442 	unsigned long slot_array[PPC64_HUGE_HPTE_BATCH];
443 	unsigned long shift, hidx, vpn = 0, vsid, hash, slot;
444 
445 	shift = mmu_psize_defs[psize].shift;
446 	max_hpte_count = 1U << (PMD_SHIFT - shift);
447 
448 	for (i = 0; i < max_hpte_count; i++) {
449 		valid = hpte_valid(hpte_slot_array, i);
450 		if (!valid)
451 			continue;
452 		hidx =  hpte_hash_index(hpte_slot_array, i);
453 
454 		/* get the vpn */
455 		addr = s_addr + (i * (1ul << shift));
456 		if (!is_kernel_addr(addr)) {
457 			ssize = user_segment_size(addr);
458 			vsid = get_vsid(mm->context.id, addr, ssize);
459 			WARN_ON(vsid == 0);
460 		} else {
461 			vsid = get_kernel_vsid(addr, mmu_kernel_ssize);
462 			ssize = mmu_kernel_ssize;
463 		}
464 
465 		vpn = hpt_vpn(addr, vsid, ssize);
466 		hash = hpt_hash(vpn, shift, ssize);
467 		if (hidx & _PTEIDX_SECONDARY)
468 			hash = ~hash;
469 
470 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
471 		slot += hidx & _PTEIDX_GROUP_IX;
472 
473 		slot_array[index] = slot;
474 		vpn_array[index] = vpn;
475 		if (index == PPC64_HUGE_HPTE_BATCH - 1) {
476 			/*
477 			 * Now do a bluk invalidate
478 			 */
479 			__pSeries_lpar_hugepage_invalidate(slot_array,
480 							   vpn_array,
481 							   PPC64_HUGE_HPTE_BATCH,
482 							   psize, ssize);
483 			index = 0;
484 		} else
485 			index++;
486 	}
487 	if (index)
488 		__pSeries_lpar_hugepage_invalidate(slot_array, vpn_array,
489 						   index, psize, ssize);
490 }
491 
492 static void pSeries_lpar_hpte_removebolted(unsigned long ea,
493 					   int psize, int ssize)
494 {
495 	unsigned long vpn;
496 	unsigned long slot, vsid;
497 
498 	vsid = get_kernel_vsid(ea, ssize);
499 	vpn = hpt_vpn(ea, vsid, ssize);
500 
501 	slot = pSeries_lpar_hpte_find(vpn, psize, ssize);
502 	BUG_ON(slot == -1);
503 	/*
504 	 * lpar doesn't use the passed actual page size
505 	 */
506 	pSeries_lpar_hpte_invalidate(slot, vpn, psize, 0, ssize, 0);
507 }
508 
509 /*
510  * Take a spinlock around flushes to avoid bouncing the hypervisor tlbie
511  * lock.
512  */
513 static void pSeries_lpar_flush_hash_range(unsigned long number, int local)
514 {
515 	unsigned long vpn;
516 	unsigned long i, pix, rc;
517 	unsigned long flags = 0;
518 	struct ppc64_tlb_batch *batch = &__get_cpu_var(ppc64_tlb_batch);
519 	int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
520 	unsigned long param[9];
521 	unsigned long hash, index, shift, hidx, slot;
522 	real_pte_t pte;
523 	int psize, ssize;
524 
525 	if (lock_tlbie)
526 		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
527 
528 	psize = batch->psize;
529 	ssize = batch->ssize;
530 	pix = 0;
531 	for (i = 0; i < number; i++) {
532 		vpn = batch->vpn[i];
533 		pte = batch->pte[i];
534 		pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) {
535 			hash = hpt_hash(vpn, shift, ssize);
536 			hidx = __rpte_to_hidx(pte, index);
537 			if (hidx & _PTEIDX_SECONDARY)
538 				hash = ~hash;
539 			slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
540 			slot += hidx & _PTEIDX_GROUP_IX;
541 			if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
542 				/*
543 				 * lpar doesn't use the passed actual page size
544 				 */
545 				pSeries_lpar_hpte_invalidate(slot, vpn, psize,
546 							     0, ssize, local);
547 			} else {
548 				param[pix] = HBR_REQUEST | HBR_AVPN | slot;
549 				param[pix+1] = hpte_encode_avpn(vpn, psize,
550 								ssize);
551 				pix += 2;
552 				if (pix == 8) {
553 					rc = plpar_hcall9(H_BULK_REMOVE, param,
554 						param[0], param[1], param[2],
555 						param[3], param[4], param[5],
556 						param[6], param[7]);
557 					BUG_ON(rc != H_SUCCESS);
558 					pix = 0;
559 				}
560 			}
561 		} pte_iterate_hashed_end();
562 	}
563 	if (pix) {
564 		param[pix] = HBR_END;
565 		rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
566 				  param[2], param[3], param[4], param[5],
567 				  param[6], param[7]);
568 		BUG_ON(rc != H_SUCCESS);
569 	}
570 
571 	if (lock_tlbie)
572 		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
573 }
574 
575 static int __init disable_bulk_remove(char *str)
576 {
577 	if (strcmp(str, "off") == 0 &&
578 	    firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
579 			printk(KERN_INFO "Disabling BULK_REMOVE firmware feature");
580 			powerpc_firmware_features &= ~FW_FEATURE_BULK_REMOVE;
581 	}
582 	return 1;
583 }
584 
585 __setup("bulk_remove=", disable_bulk_remove);
586 
587 void __init hpte_init_lpar(void)
588 {
589 	ppc_md.hpte_invalidate	= pSeries_lpar_hpte_invalidate;
590 	ppc_md.hpte_updatepp	= pSeries_lpar_hpte_updatepp;
591 	ppc_md.hpte_updateboltedpp = pSeries_lpar_hpte_updateboltedpp;
592 	ppc_md.hpte_insert	= pSeries_lpar_hpte_insert;
593 	ppc_md.hpte_remove	= pSeries_lpar_hpte_remove;
594 	ppc_md.hpte_removebolted = pSeries_lpar_hpte_removebolted;
595 	ppc_md.flush_hash_range	= pSeries_lpar_flush_hash_range;
596 	ppc_md.hpte_clear_all   = pSeries_lpar_hptab_clear;
597 	ppc_md.hugepage_invalidate = pSeries_lpar_hugepage_invalidate;
598 }
599 
600 #ifdef CONFIG_PPC_SMLPAR
601 #define CMO_FREE_HINT_DEFAULT 1
602 static int cmo_free_hint_flag = CMO_FREE_HINT_DEFAULT;
603 
604 static int __init cmo_free_hint(char *str)
605 {
606 	char *parm;
607 	parm = strstrip(str);
608 
609 	if (strcasecmp(parm, "no") == 0 || strcasecmp(parm, "off") == 0) {
610 		printk(KERN_INFO "cmo_free_hint: CMO free page hinting is not active.\n");
611 		cmo_free_hint_flag = 0;
612 		return 1;
613 	}
614 
615 	cmo_free_hint_flag = 1;
616 	printk(KERN_INFO "cmo_free_hint: CMO free page hinting is active.\n");
617 
618 	if (strcasecmp(parm, "yes") == 0 || strcasecmp(parm, "on") == 0)
619 		return 1;
620 
621 	return 0;
622 }
623 
624 __setup("cmo_free_hint=", cmo_free_hint);
625 
626 static void pSeries_set_page_state(struct page *page, int order,
627 				   unsigned long state)
628 {
629 	int i, j;
630 	unsigned long cmo_page_sz, addr;
631 
632 	cmo_page_sz = cmo_get_page_size();
633 	addr = __pa((unsigned long)page_address(page));
634 
635 	for (i = 0; i < (1 << order); i++, addr += PAGE_SIZE) {
636 		for (j = 0; j < PAGE_SIZE; j += cmo_page_sz)
637 			plpar_hcall_norets(H_PAGE_INIT, state, addr + j, 0);
638 	}
639 }
640 
641 void arch_free_page(struct page *page, int order)
642 {
643 	if (!cmo_free_hint_flag || !firmware_has_feature(FW_FEATURE_CMO))
644 		return;
645 
646 	pSeries_set_page_state(page, order, H_PAGE_SET_UNUSED);
647 }
648 EXPORT_SYMBOL(arch_free_page);
649 
650 #endif
651 
652 #ifdef CONFIG_TRACEPOINTS
653 #ifdef CONFIG_JUMP_LABEL
654 struct static_key hcall_tracepoint_key = STATIC_KEY_INIT;
655 
656 void hcall_tracepoint_regfunc(void)
657 {
658 	static_key_slow_inc(&hcall_tracepoint_key);
659 }
660 
661 void hcall_tracepoint_unregfunc(void)
662 {
663 	static_key_slow_dec(&hcall_tracepoint_key);
664 }
665 #else
666 /*
667  * We optimise our hcall path by placing hcall_tracepoint_refcount
668  * directly in the TOC so we can check if the hcall tracepoints are
669  * enabled via a single load.
670  */
671 
672 /* NB: reg/unreg are called while guarded with the tracepoints_mutex */
673 extern long hcall_tracepoint_refcount;
674 
675 void hcall_tracepoint_regfunc(void)
676 {
677 	hcall_tracepoint_refcount++;
678 }
679 
680 void hcall_tracepoint_unregfunc(void)
681 {
682 	hcall_tracepoint_refcount--;
683 }
684 #endif
685 
686 /*
687  * Since the tracing code might execute hcalls we need to guard against
688  * recursion. One example of this are spinlocks calling H_YIELD on
689  * shared processor partitions.
690  */
691 static DEFINE_PER_CPU(unsigned int, hcall_trace_depth);
692 
693 
694 void __trace_hcall_entry(unsigned long opcode, unsigned long *args)
695 {
696 	unsigned long flags;
697 	unsigned int *depth;
698 
699 	/*
700 	 * We cannot call tracepoints inside RCU idle regions which
701 	 * means we must not trace H_CEDE.
702 	 */
703 	if (opcode == H_CEDE)
704 		return;
705 
706 	local_irq_save(flags);
707 
708 	depth = &__get_cpu_var(hcall_trace_depth);
709 
710 	if (*depth)
711 		goto out;
712 
713 	(*depth)++;
714 	preempt_disable();
715 	trace_hcall_entry(opcode, args);
716 	(*depth)--;
717 
718 out:
719 	local_irq_restore(flags);
720 }
721 
722 void __trace_hcall_exit(long opcode, unsigned long retval,
723 			unsigned long *retbuf)
724 {
725 	unsigned long flags;
726 	unsigned int *depth;
727 
728 	if (opcode == H_CEDE)
729 		return;
730 
731 	local_irq_save(flags);
732 
733 	depth = &__get_cpu_var(hcall_trace_depth);
734 
735 	if (*depth)
736 		goto out;
737 
738 	(*depth)++;
739 	trace_hcall_exit(opcode, retval, retbuf);
740 	preempt_enable();
741 	(*depth)--;
742 
743 out:
744 	local_irq_restore(flags);
745 }
746 #endif
747 
748 /**
749  * h_get_mpp
750  * H_GET_MPP hcall returns info in 7 parms
751  */
752 int h_get_mpp(struct hvcall_mpp_data *mpp_data)
753 {
754 	int rc;
755 	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
756 
757 	rc = plpar_hcall9(H_GET_MPP, retbuf);
758 
759 	mpp_data->entitled_mem = retbuf[0];
760 	mpp_data->mapped_mem = retbuf[1];
761 
762 	mpp_data->group_num = (retbuf[2] >> 2 * 8) & 0xffff;
763 	mpp_data->pool_num = retbuf[2] & 0xffff;
764 
765 	mpp_data->mem_weight = (retbuf[3] >> 7 * 8) & 0xff;
766 	mpp_data->unallocated_mem_weight = (retbuf[3] >> 6 * 8) & 0xff;
767 	mpp_data->unallocated_entitlement = retbuf[3] & 0xffffffffffffUL;
768 
769 	mpp_data->pool_size = retbuf[4];
770 	mpp_data->loan_request = retbuf[5];
771 	mpp_data->backing_mem = retbuf[6];
772 
773 	return rc;
774 }
775 EXPORT_SYMBOL(h_get_mpp);
776 
777 int h_get_mpp_x(struct hvcall_mpp_x_data *mpp_x_data)
778 {
779 	int rc;
780 	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE] = { 0 };
781 
782 	rc = plpar_hcall9(H_GET_MPP_X, retbuf);
783 
784 	mpp_x_data->coalesced_bytes = retbuf[0];
785 	mpp_x_data->pool_coalesced_bytes = retbuf[1];
786 	mpp_x_data->pool_purr_cycles = retbuf[2];
787 	mpp_x_data->pool_spurr_cycles = retbuf[3];
788 
789 	return rc;
790 }
791