xref: /openbmc/linux/arch/arm64/kvm/vgic/vgic-v3.c (revision e7bae9bb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <linux/irqchip/arm-gic-v3.h>
4 #include <linux/kvm.h>
5 #include <linux/kvm_host.h>
6 #include <kvm/arm_vgic.h>
7 #include <asm/kvm_hyp.h>
8 #include <asm/kvm_mmu.h>
9 #include <asm/kvm_asm.h>
10 
11 #include "vgic.h"
12 
13 static bool group0_trap;
14 static bool group1_trap;
15 static bool common_trap;
16 static bool gicv4_enable;
17 
18 void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
19 {
20 	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
21 
22 	cpuif->vgic_hcr |= ICH_HCR_UIE;
23 }
24 
25 static bool lr_signals_eoi_mi(u64 lr_val)
26 {
27 	return !(lr_val & ICH_LR_STATE) && (lr_val & ICH_LR_EOI) &&
28 	       !(lr_val & ICH_LR_HW);
29 }
30 
31 void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
32 {
33 	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
34 	struct vgic_v3_cpu_if *cpuif = &vgic_cpu->vgic_v3;
35 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
36 	int lr;
37 
38 	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
39 
40 	cpuif->vgic_hcr &= ~ICH_HCR_UIE;
41 
42 	for (lr = 0; lr < cpuif->used_lrs; lr++) {
43 		u64 val = cpuif->vgic_lr[lr];
44 		u32 intid, cpuid;
45 		struct vgic_irq *irq;
46 		bool is_v2_sgi = false;
47 
48 		cpuid = val & GICH_LR_PHYSID_CPUID;
49 		cpuid >>= GICH_LR_PHYSID_CPUID_SHIFT;
50 
51 		if (model == KVM_DEV_TYPE_ARM_VGIC_V3) {
52 			intid = val & ICH_LR_VIRTUAL_ID_MASK;
53 		} else {
54 			intid = val & GICH_LR_VIRTUALID;
55 			is_v2_sgi = vgic_irq_is_sgi(intid);
56 		}
57 
58 		/* Notify fds when the guest EOI'ed a level-triggered IRQ */
59 		if (lr_signals_eoi_mi(val) && vgic_valid_spi(vcpu->kvm, intid))
60 			kvm_notify_acked_irq(vcpu->kvm, 0,
61 					     intid - VGIC_NR_PRIVATE_IRQS);
62 
63 		irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
64 		if (!irq)	/* An LPI could have been unmapped. */
65 			continue;
66 
67 		raw_spin_lock(&irq->irq_lock);
68 
69 		/* Always preserve the active bit */
70 		irq->active = !!(val & ICH_LR_ACTIVE_BIT);
71 
72 		if (irq->active && is_v2_sgi)
73 			irq->active_source = cpuid;
74 
75 		/* Edge is the only case where we preserve the pending bit */
76 		if (irq->config == VGIC_CONFIG_EDGE &&
77 		    (val & ICH_LR_PENDING_BIT)) {
78 			irq->pending_latch = true;
79 
80 			if (is_v2_sgi)
81 				irq->source |= (1 << cpuid);
82 		}
83 
84 		/*
85 		 * Clear soft pending state when level irqs have been acked.
86 		 */
87 		if (irq->config == VGIC_CONFIG_LEVEL && !(val & ICH_LR_STATE))
88 			irq->pending_latch = false;
89 
90 		/*
91 		 * Level-triggered mapped IRQs are special because we only
92 		 * observe rising edges as input to the VGIC.
93 		 *
94 		 * If the guest never acked the interrupt we have to sample
95 		 * the physical line and set the line level, because the
96 		 * device state could have changed or we simply need to
97 		 * process the still pending interrupt later.
98 		 *
99 		 * If this causes us to lower the level, we have to also clear
100 		 * the physical active state, since we will otherwise never be
101 		 * told when the interrupt becomes asserted again.
102 		 */
103 		if (vgic_irq_is_mapped_level(irq) && (val & ICH_LR_PENDING_BIT)) {
104 			irq->line_level = vgic_get_phys_line_level(irq);
105 
106 			if (!irq->line_level)
107 				vgic_irq_set_phys_active(irq, false);
108 		}
109 
110 		raw_spin_unlock(&irq->irq_lock);
111 		vgic_put_irq(vcpu->kvm, irq);
112 	}
113 
114 	cpuif->used_lrs = 0;
115 }
116 
117 /* Requires the irq to be locked already */
118 void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
119 {
120 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
121 	u64 val = irq->intid;
122 	bool allow_pending = true, is_v2_sgi;
123 
124 	is_v2_sgi = (vgic_irq_is_sgi(irq->intid) &&
125 		     model == KVM_DEV_TYPE_ARM_VGIC_V2);
126 
127 	if (irq->active) {
128 		val |= ICH_LR_ACTIVE_BIT;
129 		if (is_v2_sgi)
130 			val |= irq->active_source << GICH_LR_PHYSID_CPUID_SHIFT;
131 		if (vgic_irq_is_multi_sgi(irq)) {
132 			allow_pending = false;
133 			val |= ICH_LR_EOI;
134 		}
135 	}
136 
137 	if (irq->hw) {
138 		val |= ICH_LR_HW;
139 		val |= ((u64)irq->hwintid) << ICH_LR_PHYS_ID_SHIFT;
140 		/*
141 		 * Never set pending+active on a HW interrupt, as the
142 		 * pending state is kept at the physical distributor
143 		 * level.
144 		 */
145 		if (irq->active)
146 			allow_pending = false;
147 	} else {
148 		if (irq->config == VGIC_CONFIG_LEVEL) {
149 			val |= ICH_LR_EOI;
150 
151 			/*
152 			 * Software resampling doesn't work very well
153 			 * if we allow P+A, so let's not do that.
154 			 */
155 			if (irq->active)
156 				allow_pending = false;
157 		}
158 	}
159 
160 	if (allow_pending && irq_is_pending(irq)) {
161 		val |= ICH_LR_PENDING_BIT;
162 
163 		if (irq->config == VGIC_CONFIG_EDGE)
164 			irq->pending_latch = false;
165 
166 		if (vgic_irq_is_sgi(irq->intid) &&
167 		    model == KVM_DEV_TYPE_ARM_VGIC_V2) {
168 			u32 src = ffs(irq->source);
169 
170 			if (WARN_RATELIMIT(!src, "No SGI source for INTID %d\n",
171 					   irq->intid))
172 				return;
173 
174 			val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT;
175 			irq->source &= ~(1 << (src - 1));
176 			if (irq->source) {
177 				irq->pending_latch = true;
178 				val |= ICH_LR_EOI;
179 			}
180 		}
181 	}
182 
183 	/*
184 	 * Level-triggered mapped IRQs are special because we only observe
185 	 * rising edges as input to the VGIC.  We therefore lower the line
186 	 * level here, so that we can take new virtual IRQs.  See
187 	 * vgic_v3_fold_lr_state for more info.
188 	 */
189 	if (vgic_irq_is_mapped_level(irq) && (val & ICH_LR_PENDING_BIT))
190 		irq->line_level = false;
191 
192 	if (irq->group)
193 		val |= ICH_LR_GROUP;
194 
195 	val |= (u64)irq->priority << ICH_LR_PRIORITY_SHIFT;
196 
197 	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = val;
198 }
199 
200 void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
201 {
202 	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = 0;
203 }
204 
205 void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
206 {
207 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
208 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
209 	u32 vmcr;
210 
211 	if (model == KVM_DEV_TYPE_ARM_VGIC_V2) {
212 		vmcr = (vmcrp->ackctl << ICH_VMCR_ACK_CTL_SHIFT) &
213 			ICH_VMCR_ACK_CTL_MASK;
214 		vmcr |= (vmcrp->fiqen << ICH_VMCR_FIQ_EN_SHIFT) &
215 			ICH_VMCR_FIQ_EN_MASK;
216 	} else {
217 		/*
218 		 * When emulating GICv3 on GICv3 with SRE=1 on the
219 		 * VFIQEn bit is RES1 and the VAckCtl bit is RES0.
220 		 */
221 		vmcr = ICH_VMCR_FIQ_EN_MASK;
222 	}
223 
224 	vmcr |= (vmcrp->cbpr << ICH_VMCR_CBPR_SHIFT) & ICH_VMCR_CBPR_MASK;
225 	vmcr |= (vmcrp->eoim << ICH_VMCR_EOIM_SHIFT) & ICH_VMCR_EOIM_MASK;
226 	vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
227 	vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
228 	vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
229 	vmcr |= (vmcrp->grpen0 << ICH_VMCR_ENG0_SHIFT) & ICH_VMCR_ENG0_MASK;
230 	vmcr |= (vmcrp->grpen1 << ICH_VMCR_ENG1_SHIFT) & ICH_VMCR_ENG1_MASK;
231 
232 	cpu_if->vgic_vmcr = vmcr;
233 }
234 
235 void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
236 {
237 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
238 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
239 	u32 vmcr;
240 
241 	vmcr = cpu_if->vgic_vmcr;
242 
243 	if (model == KVM_DEV_TYPE_ARM_VGIC_V2) {
244 		vmcrp->ackctl = (vmcr & ICH_VMCR_ACK_CTL_MASK) >>
245 			ICH_VMCR_ACK_CTL_SHIFT;
246 		vmcrp->fiqen = (vmcr & ICH_VMCR_FIQ_EN_MASK) >>
247 			ICH_VMCR_FIQ_EN_SHIFT;
248 	} else {
249 		/*
250 		 * When emulating GICv3 on GICv3 with SRE=1 on the
251 		 * VFIQEn bit is RES1 and the VAckCtl bit is RES0.
252 		 */
253 		vmcrp->fiqen = 1;
254 		vmcrp->ackctl = 0;
255 	}
256 
257 	vmcrp->cbpr = (vmcr & ICH_VMCR_CBPR_MASK) >> ICH_VMCR_CBPR_SHIFT;
258 	vmcrp->eoim = (vmcr & ICH_VMCR_EOIM_MASK) >> ICH_VMCR_EOIM_SHIFT;
259 	vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
260 	vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
261 	vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
262 	vmcrp->grpen0 = (vmcr & ICH_VMCR_ENG0_MASK) >> ICH_VMCR_ENG0_SHIFT;
263 	vmcrp->grpen1 = (vmcr & ICH_VMCR_ENG1_MASK) >> ICH_VMCR_ENG1_SHIFT;
264 }
265 
266 #define INITIAL_PENDBASER_VALUE						  \
267 	(GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, RaWb)		| \
268 	GIC_BASER_CACHEABILITY(GICR_PENDBASER, OUTER, SameAsInner)	| \
269 	GIC_BASER_SHAREABILITY(GICR_PENDBASER, InnerShareable))
270 
271 void vgic_v3_enable(struct kvm_vcpu *vcpu)
272 {
273 	struct vgic_v3_cpu_if *vgic_v3 = &vcpu->arch.vgic_cpu.vgic_v3;
274 
275 	/*
276 	 * By forcing VMCR to zero, the GIC will restore the binary
277 	 * points to their reset values. Anything else resets to zero
278 	 * anyway.
279 	 */
280 	vgic_v3->vgic_vmcr = 0;
281 
282 	/*
283 	 * If we are emulating a GICv3, we do it in an non-GICv2-compatible
284 	 * way, so we force SRE to 1 to demonstrate this to the guest.
285 	 * Also, we don't support any form of IRQ/FIQ bypass.
286 	 * This goes with the spec allowing the value to be RAO/WI.
287 	 */
288 	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
289 		vgic_v3->vgic_sre = (ICC_SRE_EL1_DIB |
290 				     ICC_SRE_EL1_DFB |
291 				     ICC_SRE_EL1_SRE);
292 		vcpu->arch.vgic_cpu.pendbaser = INITIAL_PENDBASER_VALUE;
293 	} else {
294 		vgic_v3->vgic_sre = 0;
295 	}
296 
297 	vcpu->arch.vgic_cpu.num_id_bits = (kvm_vgic_global_state.ich_vtr_el2 &
298 					   ICH_VTR_ID_BITS_MASK) >>
299 					   ICH_VTR_ID_BITS_SHIFT;
300 	vcpu->arch.vgic_cpu.num_pri_bits = ((kvm_vgic_global_state.ich_vtr_el2 &
301 					    ICH_VTR_PRI_BITS_MASK) >>
302 					    ICH_VTR_PRI_BITS_SHIFT) + 1;
303 
304 	/* Get the show on the road... */
305 	vgic_v3->vgic_hcr = ICH_HCR_EN;
306 	if (group0_trap)
307 		vgic_v3->vgic_hcr |= ICH_HCR_TALL0;
308 	if (group1_trap)
309 		vgic_v3->vgic_hcr |= ICH_HCR_TALL1;
310 	if (common_trap)
311 		vgic_v3->vgic_hcr |= ICH_HCR_TC;
312 }
313 
314 int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq)
315 {
316 	struct kvm_vcpu *vcpu;
317 	int byte_offset, bit_nr;
318 	gpa_t pendbase, ptr;
319 	bool status;
320 	u8 val;
321 	int ret;
322 	unsigned long flags;
323 
324 retry:
325 	vcpu = irq->target_vcpu;
326 	if (!vcpu)
327 		return 0;
328 
329 	pendbase = GICR_PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);
330 
331 	byte_offset = irq->intid / BITS_PER_BYTE;
332 	bit_nr = irq->intid % BITS_PER_BYTE;
333 	ptr = pendbase + byte_offset;
334 
335 	ret = kvm_read_guest_lock(kvm, ptr, &val, 1);
336 	if (ret)
337 		return ret;
338 
339 	status = val & (1 << bit_nr);
340 
341 	raw_spin_lock_irqsave(&irq->irq_lock, flags);
342 	if (irq->target_vcpu != vcpu) {
343 		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
344 		goto retry;
345 	}
346 	irq->pending_latch = status;
347 	vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
348 
349 	if (status) {
350 		/* clear consumed data */
351 		val &= ~(1 << bit_nr);
352 		ret = kvm_write_guest_lock(kvm, ptr, &val, 1);
353 		if (ret)
354 			return ret;
355 	}
356 	return 0;
357 }
358 
359 /**
360  * vgic_v3_save_pending_tables - Save the pending tables into guest RAM
361  * kvm lock and all vcpu lock must be held
362  */
363 int vgic_v3_save_pending_tables(struct kvm *kvm)
364 {
365 	struct vgic_dist *dist = &kvm->arch.vgic;
366 	struct vgic_irq *irq;
367 	gpa_t last_ptr = ~(gpa_t)0;
368 	int ret;
369 	u8 val;
370 
371 	list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
372 		int byte_offset, bit_nr;
373 		struct kvm_vcpu *vcpu;
374 		gpa_t pendbase, ptr;
375 		bool stored;
376 
377 		vcpu = irq->target_vcpu;
378 		if (!vcpu)
379 			continue;
380 
381 		pendbase = GICR_PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);
382 
383 		byte_offset = irq->intid / BITS_PER_BYTE;
384 		bit_nr = irq->intid % BITS_PER_BYTE;
385 		ptr = pendbase + byte_offset;
386 
387 		if (ptr != last_ptr) {
388 			ret = kvm_read_guest_lock(kvm, ptr, &val, 1);
389 			if (ret)
390 				return ret;
391 			last_ptr = ptr;
392 		}
393 
394 		stored = val & (1U << bit_nr);
395 		if (stored == irq->pending_latch)
396 			continue;
397 
398 		if (irq->pending_latch)
399 			val |= 1 << bit_nr;
400 		else
401 			val &= ~(1 << bit_nr);
402 
403 		ret = kvm_write_guest_lock(kvm, ptr, &val, 1);
404 		if (ret)
405 			return ret;
406 	}
407 	return 0;
408 }
409 
410 /**
411  * vgic_v3_rdist_overlap - check if a region overlaps with any
412  * existing redistributor region
413  *
414  * @kvm: kvm handle
415  * @base: base of the region
416  * @size: size of region
417  *
418  * Return: true if there is an overlap
419  */
420 bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size)
421 {
422 	struct vgic_dist *d = &kvm->arch.vgic;
423 	struct vgic_redist_region *rdreg;
424 
425 	list_for_each_entry(rdreg, &d->rd_regions, list) {
426 		if ((base + size > rdreg->base) &&
427 			(base < rdreg->base + vgic_v3_rd_region_size(kvm, rdreg)))
428 			return true;
429 	}
430 	return false;
431 }
432 
433 /*
434  * Check for overlapping regions and for regions crossing the end of memory
435  * for base addresses which have already been set.
436  */
437 bool vgic_v3_check_base(struct kvm *kvm)
438 {
439 	struct vgic_dist *d = &kvm->arch.vgic;
440 	struct vgic_redist_region *rdreg;
441 
442 	if (!IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) &&
443 	    d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
444 		return false;
445 
446 	list_for_each_entry(rdreg, &d->rd_regions, list) {
447 		if (rdreg->base + vgic_v3_rd_region_size(kvm, rdreg) <
448 			rdreg->base)
449 			return false;
450 	}
451 
452 	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base))
453 		return true;
454 
455 	return !vgic_v3_rdist_overlap(kvm, d->vgic_dist_base,
456 				      KVM_VGIC_V3_DIST_SIZE);
457 }
458 
459 /**
460  * vgic_v3_rdist_free_slot - Look up registered rdist regions and identify one
461  * which has free space to put a new rdist region.
462  *
463  * @rd_regions: redistributor region list head
464  *
465  * A redistributor regions maps n redistributors, n = region size / (2 x 64kB).
466  * Stride between redistributors is 0 and regions are filled in the index order.
467  *
468  * Return: the redist region handle, if any, that has space to map a new rdist
469  * region.
470  */
471 struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rd_regions)
472 {
473 	struct vgic_redist_region *rdreg;
474 
475 	list_for_each_entry(rdreg, rd_regions, list) {
476 		if (!vgic_v3_redist_region_full(rdreg))
477 			return rdreg;
478 	}
479 	return NULL;
480 }
481 
482 struct vgic_redist_region *vgic_v3_rdist_region_from_index(struct kvm *kvm,
483 							   u32 index)
484 {
485 	struct list_head *rd_regions = &kvm->arch.vgic.rd_regions;
486 	struct vgic_redist_region *rdreg;
487 
488 	list_for_each_entry(rdreg, rd_regions, list) {
489 		if (rdreg->index == index)
490 			return rdreg;
491 	}
492 	return NULL;
493 }
494 
495 
496 int vgic_v3_map_resources(struct kvm *kvm)
497 {
498 	struct vgic_dist *dist = &kvm->arch.vgic;
499 	struct kvm_vcpu *vcpu;
500 	int ret = 0;
501 	int c;
502 
503 	if (vgic_ready(kvm))
504 		goto out;
505 
506 	kvm_for_each_vcpu(c, vcpu, kvm) {
507 		struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
508 
509 		if (IS_VGIC_ADDR_UNDEF(vgic_cpu->rd_iodev.base_addr)) {
510 			kvm_debug("vcpu %d redistributor base not set\n", c);
511 			ret = -ENXIO;
512 			goto out;
513 		}
514 	}
515 
516 	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base)) {
517 		kvm_err("Need to set vgic distributor addresses first\n");
518 		ret = -ENXIO;
519 		goto out;
520 	}
521 
522 	if (!vgic_v3_check_base(kvm)) {
523 		kvm_err("VGIC redist and dist frames overlap\n");
524 		ret = -EINVAL;
525 		goto out;
526 	}
527 
528 	/*
529 	 * For a VGICv3 we require the userland to explicitly initialize
530 	 * the VGIC before we need to use it.
531 	 */
532 	if (!vgic_initialized(kvm)) {
533 		ret = -EBUSY;
534 		goto out;
535 	}
536 
537 	ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V3);
538 	if (ret) {
539 		kvm_err("Unable to register VGICv3 dist MMIO regions\n");
540 		goto out;
541 	}
542 
543 	if (kvm_vgic_global_state.has_gicv4_1)
544 		vgic_v4_configure_vsgis(kvm);
545 	dist->ready = true;
546 
547 out:
548 	return ret;
549 }
550 
551 DEFINE_STATIC_KEY_FALSE(vgic_v3_cpuif_trap);
552 
553 static int __init early_group0_trap_cfg(char *buf)
554 {
555 	return strtobool(buf, &group0_trap);
556 }
557 early_param("kvm-arm.vgic_v3_group0_trap", early_group0_trap_cfg);
558 
559 static int __init early_group1_trap_cfg(char *buf)
560 {
561 	return strtobool(buf, &group1_trap);
562 }
563 early_param("kvm-arm.vgic_v3_group1_trap", early_group1_trap_cfg);
564 
565 static int __init early_common_trap_cfg(char *buf)
566 {
567 	return strtobool(buf, &common_trap);
568 }
569 early_param("kvm-arm.vgic_v3_common_trap", early_common_trap_cfg);
570 
571 static int __init early_gicv4_enable(char *buf)
572 {
573 	return strtobool(buf, &gicv4_enable);
574 }
575 early_param("kvm-arm.vgic_v4_enable", early_gicv4_enable);
576 
577 /**
578  * vgic_v3_probe - probe for a VGICv3 compatible interrupt controller
579  * @info:	pointer to the GIC description
580  *
581  * Returns 0 if the VGICv3 has been probed successfully, returns an error code
582  * otherwise
583  */
584 int vgic_v3_probe(const struct gic_kvm_info *info)
585 {
586 	u32 ich_vtr_el2 = kvm_call_hyp_ret(__vgic_v3_get_ich_vtr_el2);
587 	int ret;
588 
589 	/*
590 	 * The ListRegs field is 5 bits, but there is an architectural
591 	 * maximum of 16 list registers. Just ignore bit 4...
592 	 */
593 	kvm_vgic_global_state.nr_lr = (ich_vtr_el2 & 0xf) + 1;
594 	kvm_vgic_global_state.can_emulate_gicv2 = false;
595 	kvm_vgic_global_state.ich_vtr_el2 = ich_vtr_el2;
596 
597 	/* GICv4 support? */
598 	if (info->has_v4) {
599 		kvm_vgic_global_state.has_gicv4 = gicv4_enable;
600 		kvm_vgic_global_state.has_gicv4_1 = info->has_v4_1 && gicv4_enable;
601 		kvm_info("GICv4%s support %sabled\n",
602 			 kvm_vgic_global_state.has_gicv4_1 ? ".1" : "",
603 			 gicv4_enable ? "en" : "dis");
604 	}
605 
606 	if (!info->vcpu.start) {
607 		kvm_info("GICv3: no GICV resource entry\n");
608 		kvm_vgic_global_state.vcpu_base = 0;
609 	} else if (!PAGE_ALIGNED(info->vcpu.start)) {
610 		pr_warn("GICV physical address 0x%llx not page aligned\n",
611 			(unsigned long long)info->vcpu.start);
612 		kvm_vgic_global_state.vcpu_base = 0;
613 	} else {
614 		kvm_vgic_global_state.vcpu_base = info->vcpu.start;
615 		kvm_vgic_global_state.can_emulate_gicv2 = true;
616 		ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
617 		if (ret) {
618 			kvm_err("Cannot register GICv2 KVM device.\n");
619 			return ret;
620 		}
621 		kvm_info("vgic-v2@%llx\n", info->vcpu.start);
622 	}
623 	ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V3);
624 	if (ret) {
625 		kvm_err("Cannot register GICv3 KVM device.\n");
626 		kvm_unregister_device_ops(KVM_DEV_TYPE_ARM_VGIC_V2);
627 		return ret;
628 	}
629 
630 	if (kvm_vgic_global_state.vcpu_base == 0)
631 		kvm_info("disabling GICv2 emulation\n");
632 
633 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_30115)) {
634 		group0_trap = true;
635 		group1_trap = true;
636 	}
637 
638 	if (group0_trap || group1_trap || common_trap) {
639 		kvm_info("GICv3 sysreg trapping enabled ([%s%s%s], reduced performance)\n",
640 			 group0_trap ? "G0" : "",
641 			 group1_trap ? "G1" : "",
642 			 common_trap ? "C"  : "");
643 		static_branch_enable(&vgic_v3_cpuif_trap);
644 	}
645 
646 	kvm_vgic_global_state.vctrl_base = NULL;
647 	kvm_vgic_global_state.type = VGIC_V3;
648 	kvm_vgic_global_state.max_gic_vcpus = VGIC_V3_MAX_CPUS;
649 
650 	return 0;
651 }
652 
653 void vgic_v3_load(struct kvm_vcpu *vcpu)
654 {
655 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
656 
657 	/*
658 	 * If dealing with a GICv2 emulation on GICv3, VMCR_EL2.VFIQen
659 	 * is dependent on ICC_SRE_EL1.SRE, and we have to perform the
660 	 * VMCR_EL2 save/restore in the world switch.
661 	 */
662 	if (likely(cpu_if->vgic_sre))
663 		kvm_call_hyp(__vgic_v3_write_vmcr, cpu_if->vgic_vmcr);
664 
665 	kvm_call_hyp(__vgic_v3_restore_aprs, kern_hyp_va(cpu_if));
666 
667 	if (has_vhe())
668 		__vgic_v3_activate_traps(cpu_if);
669 
670 	WARN_ON(vgic_v4_load(vcpu));
671 }
672 
673 void vgic_v3_vmcr_sync(struct kvm_vcpu *vcpu)
674 {
675 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
676 
677 	if (likely(cpu_if->vgic_sre))
678 		cpu_if->vgic_vmcr = kvm_call_hyp_ret(__vgic_v3_read_vmcr);
679 }
680 
681 void vgic_v3_put(struct kvm_vcpu *vcpu)
682 {
683 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
684 
685 	WARN_ON(vgic_v4_put(vcpu, false));
686 
687 	vgic_v3_vmcr_sync(vcpu);
688 
689 	kvm_call_hyp(__vgic_v3_save_aprs, kern_hyp_va(cpu_if));
690 
691 	if (has_vhe())
692 		__vgic_v3_deactivate_traps(cpu_if);
693 }
694