1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
4  */
5 
6 #include <linux/cpu.h>
7 #include <linux/kvm_host.h>
8 #include <linux/preempt.h>
9 #include <linux/export.h>
10 #include <linux/sched.h>
11 #include <linux/spinlock.h>
12 #include <linux/init.h>
13 #include <linux/memblock.h>
14 #include <linux/sizes.h>
15 #include <linux/cma.h>
16 #include <linux/bitops.h>
17 
18 #include <asm/asm-prototypes.h>
19 #include <asm/cputable.h>
20 #include <asm/kvm_ppc.h>
21 #include <asm/kvm_book3s.h>
22 #include <asm/archrandom.h>
23 #include <asm/xics.h>
24 #include <asm/xive.h>
25 #include <asm/dbell.h>
26 #include <asm/cputhreads.h>
27 #include <asm/io.h>
28 #include <asm/opal.h>
29 #include <asm/smp.h>
30 
31 #define KVM_CMA_CHUNK_ORDER	18
32 
33 #include "book3s_xics.h"
34 #include "book3s_xive.h"
35 
36 /*
37  * The XIVE module will populate these when it loads
38  */
39 unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu);
40 unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server);
41 int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server,
42 		       unsigned long mfrr);
43 int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr);
44 int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr);
45 EXPORT_SYMBOL_GPL(__xive_vm_h_xirr);
46 EXPORT_SYMBOL_GPL(__xive_vm_h_ipoll);
47 EXPORT_SYMBOL_GPL(__xive_vm_h_ipi);
48 EXPORT_SYMBOL_GPL(__xive_vm_h_cppr);
49 EXPORT_SYMBOL_GPL(__xive_vm_h_eoi);
50 
51 /*
52  * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206)
53  * should be power of 2.
54  */
55 #define HPT_ALIGN_PAGES		((1 << 18) >> PAGE_SHIFT) /* 256k */
56 /*
57  * By default we reserve 5% of memory for hash pagetable allocation.
58  */
59 static unsigned long kvm_cma_resv_ratio = 5;
60 
61 static struct cma *kvm_cma;
62 
63 static int __init early_parse_kvm_cma_resv(char *p)
64 {
65 	pr_debug("%s(%s)\n", __func__, p);
66 	if (!p)
67 		return -EINVAL;
68 	return kstrtoul(p, 0, &kvm_cma_resv_ratio);
69 }
70 early_param("kvm_cma_resv_ratio", early_parse_kvm_cma_resv);
71 
72 struct page *kvm_alloc_hpt_cma(unsigned long nr_pages)
73 {
74 	VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT);
75 
76 	return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES),
77 			 false);
78 }
79 EXPORT_SYMBOL_GPL(kvm_alloc_hpt_cma);
80 
81 void kvm_free_hpt_cma(struct page *page, unsigned long nr_pages)
82 {
83 	cma_release(kvm_cma, page, nr_pages);
84 }
85 EXPORT_SYMBOL_GPL(kvm_free_hpt_cma);
86 
87 /**
88  * kvm_cma_reserve() - reserve area for kvm hash pagetable
89  *
90  * This function reserves memory from early allocator. It should be
91  * called by arch specific code once the memblock allocator
92  * has been activated and all other subsystems have already allocated/reserved
93  * memory.
94  */
95 void __init kvm_cma_reserve(void)
96 {
97 	unsigned long align_size;
98 	struct memblock_region *reg;
99 	phys_addr_t selected_size = 0;
100 
101 	/*
102 	 * We need CMA reservation only when we are in HV mode
103 	 */
104 	if (!cpu_has_feature(CPU_FTR_HVMODE))
105 		return;
106 	/*
107 	 * We cannot use memblock_phys_mem_size() here, because
108 	 * memblock_analyze() has not been called yet.
109 	 */
110 	for_each_memblock(memory, reg)
111 		selected_size += memblock_region_memory_end_pfn(reg) -
112 				 memblock_region_memory_base_pfn(reg);
113 
114 	selected_size = (selected_size * kvm_cma_resv_ratio / 100) << PAGE_SHIFT;
115 	if (selected_size) {
116 		pr_debug("%s: reserving %ld MiB for global area\n", __func__,
117 			 (unsigned long)selected_size / SZ_1M);
118 		align_size = HPT_ALIGN_PAGES << PAGE_SHIFT;
119 		cma_declare_contiguous(0, selected_size, 0, align_size,
120 			KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, false, "kvm_cma",
121 			&kvm_cma);
122 	}
123 }
124 
125 /*
126  * Real-mode H_CONFER implementation.
127  * We check if we are the only vcpu out of this virtual core
128  * still running in the guest and not ceded.  If so, we pop up
129  * to the virtual-mode implementation; if not, just return to
130  * the guest.
131  */
132 long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target,
133 			    unsigned int yield_count)
134 {
135 	struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore;
136 	int ptid = local_paca->kvm_hstate.ptid;
137 	int threads_running;
138 	int threads_ceded;
139 	int threads_conferring;
140 	u64 stop = get_tb() + 10 * tb_ticks_per_usec;
141 	int rv = H_SUCCESS; /* => don't yield */
142 
143 	set_bit(ptid, &vc->conferring_threads);
144 	while ((get_tb() < stop) && !VCORE_IS_EXITING(vc)) {
145 		threads_running = VCORE_ENTRY_MAP(vc);
146 		threads_ceded = vc->napping_threads;
147 		threads_conferring = vc->conferring_threads;
148 		if ((threads_ceded | threads_conferring) == threads_running) {
149 			rv = H_TOO_HARD; /* => do yield */
150 			break;
151 		}
152 	}
153 	clear_bit(ptid, &vc->conferring_threads);
154 	return rv;
155 }
156 
157 /*
158  * When running HV mode KVM we need to block certain operations while KVM VMs
159  * exist in the system. We use a counter of VMs to track this.
160  *
161  * One of the operations we need to block is onlining of secondaries, so we
162  * protect hv_vm_count with get/put_online_cpus().
163  */
164 static atomic_t hv_vm_count;
165 
166 void kvm_hv_vm_activated(void)
167 {
168 	get_online_cpus();
169 	atomic_inc(&hv_vm_count);
170 	put_online_cpus();
171 }
172 EXPORT_SYMBOL_GPL(kvm_hv_vm_activated);
173 
174 void kvm_hv_vm_deactivated(void)
175 {
176 	get_online_cpus();
177 	atomic_dec(&hv_vm_count);
178 	put_online_cpus();
179 }
180 EXPORT_SYMBOL_GPL(kvm_hv_vm_deactivated);
181 
182 bool kvm_hv_mode_active(void)
183 {
184 	return atomic_read(&hv_vm_count) != 0;
185 }
186 
187 extern int hcall_real_table[], hcall_real_table_end[];
188 
189 int kvmppc_hcall_impl_hv_realmode(unsigned long cmd)
190 {
191 	cmd /= 4;
192 	if (cmd < hcall_real_table_end - hcall_real_table &&
193 	    hcall_real_table[cmd])
194 		return 1;
195 
196 	return 0;
197 }
198 EXPORT_SYMBOL_GPL(kvmppc_hcall_impl_hv_realmode);
199 
200 int kvmppc_hwrng_present(void)
201 {
202 	return powernv_hwrng_present();
203 }
204 EXPORT_SYMBOL_GPL(kvmppc_hwrng_present);
205 
206 long kvmppc_h_random(struct kvm_vcpu *vcpu)
207 {
208 	int r;
209 
210 	/* Only need to do the expensive mfmsr() on radix */
211 	if (kvm_is_radix(vcpu->kvm) && (mfmsr() & MSR_IR))
212 		r = powernv_get_random_long(&vcpu->arch.regs.gpr[4]);
213 	else
214 		r = powernv_get_random_real_mode(&vcpu->arch.regs.gpr[4]);
215 	if (r)
216 		return H_SUCCESS;
217 
218 	return H_HARDWARE;
219 }
220 
221 /*
222  * Send an interrupt or message to another CPU.
223  * The caller needs to include any barrier needed to order writes
224  * to memory vs. the IPI/message.
225  */
226 void kvmhv_rm_send_ipi(int cpu)
227 {
228 	void __iomem *xics_phys;
229 	unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER);
230 
231 	/* For a nested hypervisor, use the XICS via hcall */
232 	if (kvmhv_on_pseries()) {
233 		unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
234 
235 		plpar_hcall_raw(H_IPI, retbuf, get_hard_smp_processor_id(cpu),
236 				IPI_PRIORITY);
237 		return;
238 	}
239 
240 	/* On POWER9 we can use msgsnd for any destination cpu. */
241 	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
242 		msg |= get_hard_smp_processor_id(cpu);
243 		__asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg));
244 		return;
245 	}
246 
247 	/* On POWER8 for IPIs to threads in the same core, use msgsnd. */
248 	if (cpu_has_feature(CPU_FTR_ARCH_207S) &&
249 	    cpu_first_thread_sibling(cpu) ==
250 	    cpu_first_thread_sibling(raw_smp_processor_id())) {
251 		msg |= cpu_thread_in_core(cpu);
252 		__asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg));
253 		return;
254 	}
255 
256 	/* We should never reach this */
257 	if (WARN_ON_ONCE(xics_on_xive()))
258 	    return;
259 
260 	/* Else poke the target with an IPI */
261 	xics_phys = paca_ptrs[cpu]->kvm_hstate.xics_phys;
262 	if (xics_phys)
263 		__raw_rm_writeb(IPI_PRIORITY, xics_phys + XICS_MFRR);
264 	else
265 		opal_int_set_mfrr(get_hard_smp_processor_id(cpu), IPI_PRIORITY);
266 }
267 
268 /*
269  * The following functions are called from the assembly code
270  * in book3s_hv_rmhandlers.S.
271  */
272 static void kvmhv_interrupt_vcore(struct kvmppc_vcore *vc, int active)
273 {
274 	int cpu = vc->pcpu;
275 
276 	/* Order setting of exit map vs. msgsnd/IPI */
277 	smp_mb();
278 	for (; active; active >>= 1, ++cpu)
279 		if (active & 1)
280 			kvmhv_rm_send_ipi(cpu);
281 }
282 
283 void kvmhv_commence_exit(int trap)
284 {
285 	struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore;
286 	int ptid = local_paca->kvm_hstate.ptid;
287 	struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode;
288 	int me, ee, i, t;
289 	int cpu0;
290 
291 	/* Set our bit in the threads-exiting-guest map in the 0xff00
292 	   bits of vcore->entry_exit_map */
293 	me = 0x100 << ptid;
294 	do {
295 		ee = vc->entry_exit_map;
296 	} while (cmpxchg(&vc->entry_exit_map, ee, ee | me) != ee);
297 
298 	/* Are we the first here? */
299 	if ((ee >> 8) != 0)
300 		return;
301 
302 	/*
303 	 * Trigger the other threads in this vcore to exit the guest.
304 	 * If this is a hypervisor decrementer interrupt then they
305 	 * will be already on their way out of the guest.
306 	 */
307 	if (trap != BOOK3S_INTERRUPT_HV_DECREMENTER)
308 		kvmhv_interrupt_vcore(vc, ee & ~(1 << ptid));
309 
310 	/*
311 	 * If we are doing dynamic micro-threading, interrupt the other
312 	 * subcores to pull them out of their guests too.
313 	 */
314 	if (!sip)
315 		return;
316 
317 	for (i = 0; i < MAX_SUBCORES; ++i) {
318 		vc = sip->vc[i];
319 		if (!vc)
320 			break;
321 		do {
322 			ee = vc->entry_exit_map;
323 			/* Already asked to exit? */
324 			if ((ee >> 8) != 0)
325 				break;
326 		} while (cmpxchg(&vc->entry_exit_map, ee,
327 				 ee | VCORE_EXIT_REQ) != ee);
328 		if ((ee >> 8) == 0)
329 			kvmhv_interrupt_vcore(vc, ee);
330 	}
331 
332 	/*
333 	 * On POWER9 when running a HPT guest on a radix host (sip != NULL),
334 	 * we have to interrupt inactive CPU threads to get them to
335 	 * restore the host LPCR value.
336 	 */
337 	if (sip->lpcr_req) {
338 		if (cmpxchg(&sip->do_restore, 0, 1) == 0) {
339 			vc = local_paca->kvm_hstate.kvm_vcore;
340 			cpu0 = vc->pcpu + ptid - local_paca->kvm_hstate.tid;
341 			for (t = 1; t < threads_per_core; ++t) {
342 				if (sip->napped[t])
343 					kvmhv_rm_send_ipi(cpu0 + t);
344 			}
345 		}
346 	}
347 }
348 
349 struct kvmppc_host_rm_ops *kvmppc_host_rm_ops_hv;
350 EXPORT_SYMBOL_GPL(kvmppc_host_rm_ops_hv);
351 
352 #ifdef CONFIG_KVM_XICS
353 static struct kvmppc_irq_map *get_irqmap(struct kvmppc_passthru_irqmap *pimap,
354 					 u32 xisr)
355 {
356 	int i;
357 
358 	/*
359 	 * We access the mapped array here without a lock.  That
360 	 * is safe because we never reduce the number of entries
361 	 * in the array and we never change the v_hwirq field of
362 	 * an entry once it is set.
363 	 *
364 	 * We have also carefully ordered the stores in the writer
365 	 * and the loads here in the reader, so that if we find a matching
366 	 * hwirq here, the associated GSI and irq_desc fields are valid.
367 	 */
368 	for (i = 0; i < pimap->n_mapped; i++)  {
369 		if (xisr == pimap->mapped[i].r_hwirq) {
370 			/*
371 			 * Order subsequent reads in the caller to serialize
372 			 * with the writer.
373 			 */
374 			smp_rmb();
375 			return &pimap->mapped[i];
376 		}
377 	}
378 	return NULL;
379 }
380 
381 /*
382  * If we have an interrupt that's not an IPI, check if we have a
383  * passthrough adapter and if so, check if this external interrupt
384  * is for the adapter.
385  * We will attempt to deliver the IRQ directly to the target VCPU's
386  * ICP, the virtual ICP (based on affinity - the xive value in ICS).
387  *
388  * If the delivery fails or if this is not for a passthrough adapter,
389  * return to the host to handle this interrupt. We earlier
390  * saved a copy of the XIRR in the PACA, it will be picked up by
391  * the host ICP driver.
392  */
393 static int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again)
394 {
395 	struct kvmppc_passthru_irqmap *pimap;
396 	struct kvmppc_irq_map *irq_map;
397 	struct kvm_vcpu *vcpu;
398 
399 	vcpu = local_paca->kvm_hstate.kvm_vcpu;
400 	if (!vcpu)
401 		return 1;
402 	pimap = kvmppc_get_passthru_irqmap(vcpu->kvm);
403 	if (!pimap)
404 		return 1;
405 	irq_map = get_irqmap(pimap, xisr);
406 	if (!irq_map)
407 		return 1;
408 
409 	/* We're handling this interrupt, generic code doesn't need to */
410 	local_paca->kvm_hstate.saved_xirr = 0;
411 
412 	return kvmppc_deliver_irq_passthru(vcpu, xirr, irq_map, pimap, again);
413 }
414 
415 #else
416 static inline int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again)
417 {
418 	return 1;
419 }
420 #endif
421 
422 /*
423  * Determine what sort of external interrupt is pending (if any).
424  * Returns:
425  *	0 if no interrupt is pending
426  *	1 if an interrupt is pending that needs to be handled by the host
427  *	2 Passthrough that needs completion in the host
428  *	-1 if there was a guest wakeup IPI (which has now been cleared)
429  *	-2 if there is PCI passthrough external interrupt that was handled
430  */
431 static long kvmppc_read_one_intr(bool *again);
432 
433 long kvmppc_read_intr(void)
434 {
435 	long ret = 0;
436 	long rc;
437 	bool again;
438 
439 	if (xive_enabled())
440 		return 1;
441 
442 	do {
443 		again = false;
444 		rc = kvmppc_read_one_intr(&again);
445 		if (rc && (ret == 0 || rc > ret))
446 			ret = rc;
447 	} while (again);
448 	return ret;
449 }
450 
451 static long kvmppc_read_one_intr(bool *again)
452 {
453 	void __iomem *xics_phys;
454 	u32 h_xirr;
455 	__be32 xirr;
456 	u32 xisr;
457 	u8 host_ipi;
458 	int64_t rc;
459 
460 	if (xive_enabled())
461 		return 1;
462 
463 	/* see if a host IPI is pending */
464 	host_ipi = local_paca->kvm_hstate.host_ipi;
465 	if (host_ipi)
466 		return 1;
467 
468 	/* Now read the interrupt from the ICP */
469 	if (kvmhv_on_pseries()) {
470 		unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
471 
472 		rc = plpar_hcall_raw(H_XIRR, retbuf, 0xFF);
473 		xirr = cpu_to_be32(retbuf[0]);
474 	} else {
475 		xics_phys = local_paca->kvm_hstate.xics_phys;
476 		rc = 0;
477 		if (!xics_phys)
478 			rc = opal_int_get_xirr(&xirr, false);
479 		else
480 			xirr = __raw_rm_readl(xics_phys + XICS_XIRR);
481 	}
482 	if (rc < 0)
483 		return 1;
484 
485 	/*
486 	 * Save XIRR for later. Since we get control in reverse endian
487 	 * on LE systems, save it byte reversed and fetch it back in
488 	 * host endian. Note that xirr is the value read from the
489 	 * XIRR register, while h_xirr is the host endian version.
490 	 */
491 	h_xirr = be32_to_cpu(xirr);
492 	local_paca->kvm_hstate.saved_xirr = h_xirr;
493 	xisr = h_xirr & 0xffffff;
494 	/*
495 	 * Ensure that the store/load complete to guarantee all side
496 	 * effects of loading from XIRR has completed
497 	 */
498 	smp_mb();
499 
500 	/* if nothing pending in the ICP */
501 	if (!xisr)
502 		return 0;
503 
504 	/* We found something in the ICP...
505 	 *
506 	 * If it is an IPI, clear the MFRR and EOI it.
507 	 */
508 	if (xisr == XICS_IPI) {
509 		rc = 0;
510 		if (kvmhv_on_pseries()) {
511 			unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
512 
513 			plpar_hcall_raw(H_IPI, retbuf,
514 					hard_smp_processor_id(), 0xff);
515 			plpar_hcall_raw(H_EOI, retbuf, h_xirr);
516 		} else if (xics_phys) {
517 			__raw_rm_writeb(0xff, xics_phys + XICS_MFRR);
518 			__raw_rm_writel(xirr, xics_phys + XICS_XIRR);
519 		} else {
520 			opal_int_set_mfrr(hard_smp_processor_id(), 0xff);
521 			rc = opal_int_eoi(h_xirr);
522 		}
523 		/* If rc > 0, there is another interrupt pending */
524 		*again = rc > 0;
525 
526 		/*
527 		 * Need to ensure side effects of above stores
528 		 * complete before proceeding.
529 		 */
530 		smp_mb();
531 
532 		/*
533 		 * We need to re-check host IPI now in case it got set in the
534 		 * meantime. If it's clear, we bounce the interrupt to the
535 		 * guest
536 		 */
537 		host_ipi = local_paca->kvm_hstate.host_ipi;
538 		if (unlikely(host_ipi != 0)) {
539 			/* We raced with the host,
540 			 * we need to resend that IPI, bummer
541 			 */
542 			if (kvmhv_on_pseries()) {
543 				unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
544 
545 				plpar_hcall_raw(H_IPI, retbuf,
546 						hard_smp_processor_id(),
547 						IPI_PRIORITY);
548 			} else if (xics_phys)
549 				__raw_rm_writeb(IPI_PRIORITY,
550 						xics_phys + XICS_MFRR);
551 			else
552 				opal_int_set_mfrr(hard_smp_processor_id(),
553 						  IPI_PRIORITY);
554 			/* Let side effects complete */
555 			smp_mb();
556 			return 1;
557 		}
558 
559 		/* OK, it's an IPI for us */
560 		local_paca->kvm_hstate.saved_xirr = 0;
561 		return -1;
562 	}
563 
564 	return kvmppc_check_passthru(xisr, xirr, again);
565 }
566 
567 #ifdef CONFIG_KVM_XICS
568 static inline bool is_rm(void)
569 {
570 	return !(mfmsr() & MSR_DR);
571 }
572 
573 unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu)
574 {
575 	if (!kvmppc_xics_enabled(vcpu))
576 		return H_TOO_HARD;
577 	if (xics_on_xive()) {
578 		if (is_rm())
579 			return xive_rm_h_xirr(vcpu);
580 		if (unlikely(!__xive_vm_h_xirr))
581 			return H_NOT_AVAILABLE;
582 		return __xive_vm_h_xirr(vcpu);
583 	} else
584 		return xics_rm_h_xirr(vcpu);
585 }
586 
587 unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu)
588 {
589 	if (!kvmppc_xics_enabled(vcpu))
590 		return H_TOO_HARD;
591 	vcpu->arch.regs.gpr[5] = get_tb();
592 	if (xics_on_xive()) {
593 		if (is_rm())
594 			return xive_rm_h_xirr(vcpu);
595 		if (unlikely(!__xive_vm_h_xirr))
596 			return H_NOT_AVAILABLE;
597 		return __xive_vm_h_xirr(vcpu);
598 	} else
599 		return xics_rm_h_xirr(vcpu);
600 }
601 
602 unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server)
603 {
604 	if (!kvmppc_xics_enabled(vcpu))
605 		return H_TOO_HARD;
606 	if (xics_on_xive()) {
607 		if (is_rm())
608 			return xive_rm_h_ipoll(vcpu, server);
609 		if (unlikely(!__xive_vm_h_ipoll))
610 			return H_NOT_AVAILABLE;
611 		return __xive_vm_h_ipoll(vcpu, server);
612 	} else
613 		return H_TOO_HARD;
614 }
615 
616 int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
617 		    unsigned long mfrr)
618 {
619 	if (!kvmppc_xics_enabled(vcpu))
620 		return H_TOO_HARD;
621 	if (xics_on_xive()) {
622 		if (is_rm())
623 			return xive_rm_h_ipi(vcpu, server, mfrr);
624 		if (unlikely(!__xive_vm_h_ipi))
625 			return H_NOT_AVAILABLE;
626 		return __xive_vm_h_ipi(vcpu, server, mfrr);
627 	} else
628 		return xics_rm_h_ipi(vcpu, server, mfrr);
629 }
630 
631 int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
632 {
633 	if (!kvmppc_xics_enabled(vcpu))
634 		return H_TOO_HARD;
635 	if (xics_on_xive()) {
636 		if (is_rm())
637 			return xive_rm_h_cppr(vcpu, cppr);
638 		if (unlikely(!__xive_vm_h_cppr))
639 			return H_NOT_AVAILABLE;
640 		return __xive_vm_h_cppr(vcpu, cppr);
641 	} else
642 		return xics_rm_h_cppr(vcpu, cppr);
643 }
644 
645 int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
646 {
647 	if (!kvmppc_xics_enabled(vcpu))
648 		return H_TOO_HARD;
649 	if (xics_on_xive()) {
650 		if (is_rm())
651 			return xive_rm_h_eoi(vcpu, xirr);
652 		if (unlikely(!__xive_vm_h_eoi))
653 			return H_NOT_AVAILABLE;
654 		return __xive_vm_h_eoi(vcpu, xirr);
655 	} else
656 		return xics_rm_h_eoi(vcpu, xirr);
657 }
658 #endif /* CONFIG_KVM_XICS */
659 
660 void kvmppc_bad_interrupt(struct pt_regs *regs)
661 {
662 	/*
663 	 * 100 could happen at any time, 200 can happen due to invalid real
664 	 * address access for example (or any time due to a hardware problem).
665 	 */
666 	if (TRAP(regs) == 0x100) {
667 		get_paca()->in_nmi++;
668 		system_reset_exception(regs);
669 		get_paca()->in_nmi--;
670 	} else if (TRAP(regs) == 0x200) {
671 		machine_check_exception(regs);
672 	} else {
673 		die("Bad interrupt in KVM entry/exit code", regs, SIGABRT);
674 	}
675 	panic("Bad KVM trap");
676 }
677 
678 /*
679  * Functions used to switch LPCR HR and UPRT bits on all threads
680  * when entering and exiting HPT guests on a radix host.
681  */
682 
683 #define PHASE_REALMODE		1	/* in real mode */
684 #define PHASE_SET_LPCR		2	/* have set LPCR */
685 #define PHASE_OUT_OF_GUEST	4	/* have finished executing in guest */
686 #define PHASE_RESET_LPCR	8	/* have reset LPCR to host value */
687 
688 #define ALL(p)		(((p) << 24) | ((p) << 16) | ((p) << 8) | (p))
689 
690 static void wait_for_sync(struct kvm_split_mode *sip, int phase)
691 {
692 	int thr = local_paca->kvm_hstate.tid;
693 
694 	sip->lpcr_sync.phase[thr] |= phase;
695 	phase = ALL(phase);
696 	while ((sip->lpcr_sync.allphases & phase) != phase) {
697 		HMT_low();
698 		barrier();
699 	}
700 	HMT_medium();
701 }
702 
703 void kvmhv_p9_set_lpcr(struct kvm_split_mode *sip)
704 {
705 	unsigned long rb, set;
706 
707 	/* wait for every other thread to get to real mode */
708 	wait_for_sync(sip, PHASE_REALMODE);
709 
710 	/* Set LPCR and LPIDR */
711 	mtspr(SPRN_LPCR, sip->lpcr_req);
712 	mtspr(SPRN_LPID, sip->lpidr_req);
713 	isync();
714 
715 	/* Invalidate the TLB on thread 0 */
716 	if (local_paca->kvm_hstate.tid == 0) {
717 		sip->do_set = 0;
718 		asm volatile("ptesync" : : : "memory");
719 		for (set = 0; set < POWER9_TLB_SETS_RADIX; ++set) {
720 			rb = TLBIEL_INVAL_SET_LPID +
721 				(set << TLBIEL_INVAL_SET_SHIFT);
722 			asm volatile(PPC_TLBIEL(%0, %1, 0, 0, 0) : :
723 				     "r" (rb), "r" (0));
724 		}
725 		asm volatile("ptesync" : : : "memory");
726 	}
727 
728 	/* indicate that we have done so and wait for others */
729 	wait_for_sync(sip, PHASE_SET_LPCR);
730 	/* order read of sip->lpcr_sync.allphases vs. sip->do_set */
731 	smp_rmb();
732 }
733 
734 /*
735  * Called when a thread that has been in the guest needs
736  * to reload the host LPCR value - but only on POWER9 when
737  * running a HPT guest on a radix host.
738  */
739 void kvmhv_p9_restore_lpcr(struct kvm_split_mode *sip)
740 {
741 	/* we're out of the guest... */
742 	wait_for_sync(sip, PHASE_OUT_OF_GUEST);
743 
744 	mtspr(SPRN_LPID, 0);
745 	mtspr(SPRN_LPCR, sip->host_lpcr);
746 	isync();
747 
748 	if (local_paca->kvm_hstate.tid == 0) {
749 		sip->do_restore = 0;
750 		smp_wmb();	/* order store of do_restore vs. phase */
751 	}
752 
753 	wait_for_sync(sip, PHASE_RESET_LPCR);
754 	smp_mb();
755 	local_paca->kvm_hstate.kvm_split_mode = NULL;
756 }
757 
758 /*
759  * Is there a PRIV_DOORBELL pending for the guest (on POWER9)?
760  * Can we inject a Decrementer or a External interrupt?
761  */
762 void kvmppc_guest_entry_inject_int(struct kvm_vcpu *vcpu)
763 {
764 	int ext;
765 	unsigned long vec = 0;
766 	unsigned long lpcr;
767 
768 	/* Insert EXTERNAL bit into LPCR at the MER bit position */
769 	ext = (vcpu->arch.pending_exceptions >> BOOK3S_IRQPRIO_EXTERNAL) & 1;
770 	lpcr = mfspr(SPRN_LPCR);
771 	lpcr |= ext << LPCR_MER_SH;
772 	mtspr(SPRN_LPCR, lpcr);
773 	isync();
774 
775 	if (vcpu->arch.shregs.msr & MSR_EE) {
776 		if (ext) {
777 			vec = BOOK3S_INTERRUPT_EXTERNAL;
778 		} else {
779 			long int dec = mfspr(SPRN_DEC);
780 			if (!(lpcr & LPCR_LD))
781 				dec = (int) dec;
782 			if (dec < 0)
783 				vec = BOOK3S_INTERRUPT_DECREMENTER;
784 		}
785 	}
786 	if (vec) {
787 		unsigned long msr, old_msr = vcpu->arch.shregs.msr;
788 
789 		kvmppc_set_srr0(vcpu, kvmppc_get_pc(vcpu));
790 		kvmppc_set_srr1(vcpu, old_msr);
791 		kvmppc_set_pc(vcpu, vec);
792 		msr = vcpu->arch.intr_msr;
793 		if (MSR_TM_ACTIVE(old_msr))
794 			msr |= MSR_TS_S;
795 		vcpu->arch.shregs.msr = msr;
796 	}
797 
798 	if (vcpu->arch.doorbell_request) {
799 		mtspr(SPRN_DPDES, 1);
800 		vcpu->arch.vcore->dpdes = 1;
801 		smp_wmb();
802 		vcpu->arch.doorbell_request = 0;
803 	}
804 }
805 
806 static void flush_guest_tlb(struct kvm *kvm)
807 {
808 	unsigned long rb, set;
809 
810 	rb = PPC_BIT(52);	/* IS = 2 */
811 	if (kvm_is_radix(kvm)) {
812 		/* R=1 PRS=1 RIC=2 */
813 		asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
814 			     : : "r" (rb), "i" (1), "i" (1), "i" (2),
815 			       "r" (0) : "memory");
816 		for (set = 1; set < kvm->arch.tlb_sets; ++set) {
817 			rb += PPC_BIT(51);	/* increment set number */
818 			/* R=1 PRS=1 RIC=0 */
819 			asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
820 				     : : "r" (rb), "i" (1), "i" (1), "i" (0),
821 				       "r" (0) : "memory");
822 		}
823 	} else {
824 		for (set = 0; set < kvm->arch.tlb_sets; ++set) {
825 			/* R=0 PRS=0 RIC=0 */
826 			asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
827 				     : : "r" (rb), "i" (0), "i" (0), "i" (0),
828 				       "r" (0) : "memory");
829 			rb += PPC_BIT(51);	/* increment set number */
830 		}
831 	}
832 	asm volatile("ptesync": : :"memory");
833 	asm volatile(PPC_INVALIDATE_ERAT : : :"memory");
834 }
835 
836 void kvmppc_check_need_tlb_flush(struct kvm *kvm, int pcpu,
837 				 struct kvm_nested_guest *nested)
838 {
839 	cpumask_t *need_tlb_flush;
840 
841 	/*
842 	 * On POWER9, individual threads can come in here, but the
843 	 * TLB is shared between the 4 threads in a core, hence
844 	 * invalidating on one thread invalidates for all.
845 	 * Thus we make all 4 threads use the same bit.
846 	 */
847 	if (cpu_has_feature(CPU_FTR_ARCH_300))
848 		pcpu = cpu_first_thread_sibling(pcpu);
849 
850 	if (nested)
851 		need_tlb_flush = &nested->need_tlb_flush;
852 	else
853 		need_tlb_flush = &kvm->arch.need_tlb_flush;
854 
855 	if (cpumask_test_cpu(pcpu, need_tlb_flush)) {
856 		flush_guest_tlb(kvm);
857 
858 		/* Clear the bit after the TLB flush */
859 		cpumask_clear_cpu(pcpu, need_tlb_flush);
860 	}
861 }
862 EXPORT_SYMBOL_GPL(kvmppc_check_need_tlb_flush);
863