xref: /linux/arch/arm64/kvm/vgic/vgic-v3.c (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <linux/irqchip/arm-gic-v3.h>
4 #include <linux/irq.h>
5 #include <linux/irqdomain.h>
6 #include <linux/kvm.h>
7 #include <linux/kvm_host.h>
8 #include <kvm/arm_vgic.h>
9 #include <asm/kvm_hyp.h>
10 #include <asm/kvm_mmu.h>
11 #include <asm/kvm_asm.h>
12 
13 #include "vgic.h"
14 
15 static bool group0_trap;
16 static bool group1_trap;
17 static bool common_trap;
18 static bool gicv4_enable;
19 
20 void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
21 {
22 	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
23 
24 	cpuif->vgic_hcr |= ICH_HCR_UIE;
25 }
26 
27 static bool lr_signals_eoi_mi(u64 lr_val)
28 {
29 	return !(lr_val & ICH_LR_STATE) && (lr_val & ICH_LR_EOI) &&
30 	       !(lr_val & ICH_LR_HW);
31 }
32 
33 void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
34 {
35 	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
36 	struct vgic_v3_cpu_if *cpuif = &vgic_cpu->vgic_v3;
37 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
38 	int lr;
39 
40 	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
41 
42 	cpuif->vgic_hcr &= ~ICH_HCR_UIE;
43 
44 	for (lr = 0; lr < cpuif->used_lrs; lr++) {
45 		u64 val = cpuif->vgic_lr[lr];
46 		u32 intid, cpuid;
47 		struct vgic_irq *irq;
48 		bool is_v2_sgi = false;
49 
50 		cpuid = val & GICH_LR_PHYSID_CPUID;
51 		cpuid >>= GICH_LR_PHYSID_CPUID_SHIFT;
52 
53 		if (model == KVM_DEV_TYPE_ARM_VGIC_V3) {
54 			intid = val & ICH_LR_VIRTUAL_ID_MASK;
55 		} else {
56 			intid = val & GICH_LR_VIRTUALID;
57 			is_v2_sgi = vgic_irq_is_sgi(intid);
58 		}
59 
60 		/* Notify fds when the guest EOI'ed a level-triggered IRQ */
61 		if (lr_signals_eoi_mi(val) && vgic_valid_spi(vcpu->kvm, intid))
62 			kvm_notify_acked_irq(vcpu->kvm, 0,
63 					     intid - VGIC_NR_PRIVATE_IRQS);
64 
65 		irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
66 		if (!irq)	/* An LPI could have been unmapped. */
67 			continue;
68 
69 		raw_spin_lock(&irq->irq_lock);
70 
71 		/* Always preserve the active bit */
72 		irq->active = !!(val & ICH_LR_ACTIVE_BIT);
73 
74 		if (irq->active && is_v2_sgi)
75 			irq->active_source = cpuid;
76 
77 		/* Edge is the only case where we preserve the pending bit */
78 		if (irq->config == VGIC_CONFIG_EDGE &&
79 		    (val & ICH_LR_PENDING_BIT)) {
80 			irq->pending_latch = true;
81 
82 			if (is_v2_sgi)
83 				irq->source |= (1 << cpuid);
84 		}
85 
86 		/*
87 		 * Clear soft pending state when level irqs have been acked.
88 		 */
89 		if (irq->config == VGIC_CONFIG_LEVEL && !(val & ICH_LR_STATE))
90 			irq->pending_latch = false;
91 
92 		/*
93 		 * Level-triggered mapped IRQs are special because we only
94 		 * observe rising edges as input to the VGIC.
95 		 *
96 		 * If the guest never acked the interrupt we have to sample
97 		 * the physical line and set the line level, because the
98 		 * device state could have changed or we simply need to
99 		 * process the still pending interrupt later.
100 		 *
101 		 * If this causes us to lower the level, we have to also clear
102 		 * the physical active state, since we will otherwise never be
103 		 * told when the interrupt becomes asserted again.
104 		 */
105 		if (vgic_irq_is_mapped_level(irq) && (val & ICH_LR_PENDING_BIT)) {
106 			irq->line_level = vgic_get_phys_line_level(irq);
107 
108 			if (!irq->line_level)
109 				vgic_irq_set_phys_active(irq, false);
110 		}
111 
112 		raw_spin_unlock(&irq->irq_lock);
113 		vgic_put_irq(vcpu->kvm, irq);
114 	}
115 
116 	cpuif->used_lrs = 0;
117 }
118 
119 /* Requires the irq to be locked already */
120 void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
121 {
122 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
123 	u64 val = irq->intid;
124 	bool allow_pending = true, is_v2_sgi;
125 
126 	is_v2_sgi = (vgic_irq_is_sgi(irq->intid) &&
127 		     model == KVM_DEV_TYPE_ARM_VGIC_V2);
128 
129 	if (irq->active) {
130 		val |= ICH_LR_ACTIVE_BIT;
131 		if (is_v2_sgi)
132 			val |= irq->active_source << GICH_LR_PHYSID_CPUID_SHIFT;
133 		if (vgic_irq_is_multi_sgi(irq)) {
134 			allow_pending = false;
135 			val |= ICH_LR_EOI;
136 		}
137 	}
138 
139 	if (irq->hw) {
140 		val |= ICH_LR_HW;
141 		val |= ((u64)irq->hwintid) << ICH_LR_PHYS_ID_SHIFT;
142 		/*
143 		 * Never set pending+active on a HW interrupt, as the
144 		 * pending state is kept at the physical distributor
145 		 * level.
146 		 */
147 		if (irq->active)
148 			allow_pending = false;
149 	} else {
150 		if (irq->config == VGIC_CONFIG_LEVEL) {
151 			val |= ICH_LR_EOI;
152 
153 			/*
154 			 * Software resampling doesn't work very well
155 			 * if we allow P+A, so let's not do that.
156 			 */
157 			if (irq->active)
158 				allow_pending = false;
159 		}
160 	}
161 
162 	if (allow_pending && irq_is_pending(irq)) {
163 		val |= ICH_LR_PENDING_BIT;
164 
165 		if (irq->config == VGIC_CONFIG_EDGE)
166 			irq->pending_latch = false;
167 
168 		if (vgic_irq_is_sgi(irq->intid) &&
169 		    model == KVM_DEV_TYPE_ARM_VGIC_V2) {
170 			u32 src = ffs(irq->source);
171 
172 			if (WARN_RATELIMIT(!src, "No SGI source for INTID %d\n",
173 					   irq->intid))
174 				return;
175 
176 			val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT;
177 			irq->source &= ~(1 << (src - 1));
178 			if (irq->source) {
179 				irq->pending_latch = true;
180 				val |= ICH_LR_EOI;
181 			}
182 		}
183 	}
184 
185 	/*
186 	 * Level-triggered mapped IRQs are special because we only observe
187 	 * rising edges as input to the VGIC.  We therefore lower the line
188 	 * level here, so that we can take new virtual IRQs.  See
189 	 * vgic_v3_fold_lr_state for more info.
190 	 */
191 	if (vgic_irq_is_mapped_level(irq) && (val & ICH_LR_PENDING_BIT))
192 		irq->line_level = false;
193 
194 	if (irq->group)
195 		val |= ICH_LR_GROUP;
196 
197 	val |= (u64)irq->priority << ICH_LR_PRIORITY_SHIFT;
198 
199 	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = val;
200 }
201 
202 void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
203 {
204 	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = 0;
205 }
206 
207 void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
208 {
209 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
210 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
211 	u32 vmcr;
212 
213 	if (model == KVM_DEV_TYPE_ARM_VGIC_V2) {
214 		vmcr = (vmcrp->ackctl << ICH_VMCR_ACK_CTL_SHIFT) &
215 			ICH_VMCR_ACK_CTL_MASK;
216 		vmcr |= (vmcrp->fiqen << ICH_VMCR_FIQ_EN_SHIFT) &
217 			ICH_VMCR_FIQ_EN_MASK;
218 	} else {
219 		/*
220 		 * When emulating GICv3 on GICv3 with SRE=1 on the
221 		 * VFIQEn bit is RES1 and the VAckCtl bit is RES0.
222 		 */
223 		vmcr = ICH_VMCR_FIQ_EN_MASK;
224 	}
225 
226 	vmcr |= (vmcrp->cbpr << ICH_VMCR_CBPR_SHIFT) & ICH_VMCR_CBPR_MASK;
227 	vmcr |= (vmcrp->eoim << ICH_VMCR_EOIM_SHIFT) & ICH_VMCR_EOIM_MASK;
228 	vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
229 	vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
230 	vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
231 	vmcr |= (vmcrp->grpen0 << ICH_VMCR_ENG0_SHIFT) & ICH_VMCR_ENG0_MASK;
232 	vmcr |= (vmcrp->grpen1 << ICH_VMCR_ENG1_SHIFT) & ICH_VMCR_ENG1_MASK;
233 
234 	cpu_if->vgic_vmcr = vmcr;
235 }
236 
237 void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
238 {
239 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
240 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
241 	u32 vmcr;
242 
243 	vmcr = cpu_if->vgic_vmcr;
244 
245 	if (model == KVM_DEV_TYPE_ARM_VGIC_V2) {
246 		vmcrp->ackctl = (vmcr & ICH_VMCR_ACK_CTL_MASK) >>
247 			ICH_VMCR_ACK_CTL_SHIFT;
248 		vmcrp->fiqen = (vmcr & ICH_VMCR_FIQ_EN_MASK) >>
249 			ICH_VMCR_FIQ_EN_SHIFT;
250 	} else {
251 		/*
252 		 * When emulating GICv3 on GICv3 with SRE=1 on the
253 		 * VFIQEn bit is RES1 and the VAckCtl bit is RES0.
254 		 */
255 		vmcrp->fiqen = 1;
256 		vmcrp->ackctl = 0;
257 	}
258 
259 	vmcrp->cbpr = (vmcr & ICH_VMCR_CBPR_MASK) >> ICH_VMCR_CBPR_SHIFT;
260 	vmcrp->eoim = (vmcr & ICH_VMCR_EOIM_MASK) >> ICH_VMCR_EOIM_SHIFT;
261 	vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
262 	vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
263 	vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
264 	vmcrp->grpen0 = (vmcr & ICH_VMCR_ENG0_MASK) >> ICH_VMCR_ENG0_SHIFT;
265 	vmcrp->grpen1 = (vmcr & ICH_VMCR_ENG1_MASK) >> ICH_VMCR_ENG1_SHIFT;
266 }
267 
268 #define INITIAL_PENDBASER_VALUE						  \
269 	(GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, RaWb)		| \
270 	GIC_BASER_CACHEABILITY(GICR_PENDBASER, OUTER, SameAsInner)	| \
271 	GIC_BASER_SHAREABILITY(GICR_PENDBASER, InnerShareable))
272 
273 void vgic_v3_enable(struct kvm_vcpu *vcpu)
274 {
275 	struct vgic_v3_cpu_if *vgic_v3 = &vcpu->arch.vgic_cpu.vgic_v3;
276 
277 	/*
278 	 * By forcing VMCR to zero, the GIC will restore the binary
279 	 * points to their reset values. Anything else resets to zero
280 	 * anyway.
281 	 */
282 	vgic_v3->vgic_vmcr = 0;
283 
284 	/*
285 	 * If we are emulating a GICv3, we do it in an non-GICv2-compatible
286 	 * way, so we force SRE to 1 to demonstrate this to the guest.
287 	 * Also, we don't support any form of IRQ/FIQ bypass.
288 	 * This goes with the spec allowing the value to be RAO/WI.
289 	 */
290 	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
291 		vgic_v3->vgic_sre = (ICC_SRE_EL1_DIB |
292 				     ICC_SRE_EL1_DFB |
293 				     ICC_SRE_EL1_SRE);
294 		vcpu->arch.vgic_cpu.pendbaser = INITIAL_PENDBASER_VALUE;
295 	} else {
296 		vgic_v3->vgic_sre = 0;
297 	}
298 
299 	vcpu->arch.vgic_cpu.num_id_bits = (kvm_vgic_global_state.ich_vtr_el2 &
300 					   ICH_VTR_ID_BITS_MASK) >>
301 					   ICH_VTR_ID_BITS_SHIFT;
302 	vcpu->arch.vgic_cpu.num_pri_bits = ((kvm_vgic_global_state.ich_vtr_el2 &
303 					    ICH_VTR_PRI_BITS_MASK) >>
304 					    ICH_VTR_PRI_BITS_SHIFT) + 1;
305 
306 	/* Get the show on the road... */
307 	vgic_v3->vgic_hcr = ICH_HCR_EN;
308 	if (group0_trap)
309 		vgic_v3->vgic_hcr |= ICH_HCR_TALL0;
310 	if (group1_trap)
311 		vgic_v3->vgic_hcr |= ICH_HCR_TALL1;
312 	if (common_trap)
313 		vgic_v3->vgic_hcr |= ICH_HCR_TC;
314 }
315 
316 int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq)
317 {
318 	struct kvm_vcpu *vcpu;
319 	int byte_offset, bit_nr;
320 	gpa_t pendbase, ptr;
321 	bool status;
322 	u8 val;
323 	int ret;
324 	unsigned long flags;
325 
326 retry:
327 	vcpu = irq->target_vcpu;
328 	if (!vcpu)
329 		return 0;
330 
331 	pendbase = GICR_PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);
332 
333 	byte_offset = irq->intid / BITS_PER_BYTE;
334 	bit_nr = irq->intid % BITS_PER_BYTE;
335 	ptr = pendbase + byte_offset;
336 
337 	ret = kvm_read_guest_lock(kvm, ptr, &val, 1);
338 	if (ret)
339 		return ret;
340 
341 	status = val & (1 << bit_nr);
342 
343 	raw_spin_lock_irqsave(&irq->irq_lock, flags);
344 	if (irq->target_vcpu != vcpu) {
345 		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
346 		goto retry;
347 	}
348 	irq->pending_latch = status;
349 	vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
350 
351 	if (status) {
352 		/* clear consumed data */
353 		val &= ~(1 << bit_nr);
354 		ret = kvm_write_guest_lock(kvm, ptr, &val, 1);
355 		if (ret)
356 			return ret;
357 	}
358 	return 0;
359 }
360 
361 /*
362  * The deactivation of the doorbell interrupt will trigger the
363  * unmapping of the associated vPE.
364  */
365 static void unmap_all_vpes(struct vgic_dist *dist)
366 {
367 	struct irq_desc *desc;
368 	int i;
369 
370 	for (i = 0; i < dist->its_vm.nr_vpes; i++) {
371 		desc = irq_to_desc(dist->its_vm.vpes[i]->irq);
372 		irq_domain_deactivate_irq(irq_desc_get_irq_data(desc));
373 	}
374 }
375 
376 static void map_all_vpes(struct vgic_dist *dist)
377 {
378 	struct irq_desc *desc;
379 	int i;
380 
381 	for (i = 0; i < dist->its_vm.nr_vpes; i++) {
382 		desc = irq_to_desc(dist->its_vm.vpes[i]->irq);
383 		irq_domain_activate_irq(irq_desc_get_irq_data(desc), false);
384 	}
385 }
386 
387 /**
388  * vgic_v3_save_pending_tables - Save the pending tables into guest RAM
389  * kvm lock and all vcpu lock must be held
390  */
391 int vgic_v3_save_pending_tables(struct kvm *kvm)
392 {
393 	struct vgic_dist *dist = &kvm->arch.vgic;
394 	struct vgic_irq *irq;
395 	gpa_t last_ptr = ~(gpa_t)0;
396 	bool vlpi_avail = false;
397 	int ret = 0;
398 	u8 val;
399 
400 	if (unlikely(!vgic_initialized(kvm)))
401 		return -ENXIO;
402 
403 	/*
404 	 * A preparation for getting any VLPI states.
405 	 * The above vgic initialized check also ensures that the allocation
406 	 * and enabling of the doorbells have already been done.
407 	 */
408 	if (kvm_vgic_global_state.has_gicv4_1) {
409 		unmap_all_vpes(dist);
410 		vlpi_avail = true;
411 	}
412 
413 	list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
414 		int byte_offset, bit_nr;
415 		struct kvm_vcpu *vcpu;
416 		gpa_t pendbase, ptr;
417 		bool is_pending;
418 		bool stored;
419 
420 		vcpu = irq->target_vcpu;
421 		if (!vcpu)
422 			continue;
423 
424 		pendbase = GICR_PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);
425 
426 		byte_offset = irq->intid / BITS_PER_BYTE;
427 		bit_nr = irq->intid % BITS_PER_BYTE;
428 		ptr = pendbase + byte_offset;
429 
430 		if (ptr != last_ptr) {
431 			ret = kvm_read_guest_lock(kvm, ptr, &val, 1);
432 			if (ret)
433 				goto out;
434 			last_ptr = ptr;
435 		}
436 
437 		stored = val & (1U << bit_nr);
438 
439 		is_pending = irq->pending_latch;
440 
441 		if (irq->hw && vlpi_avail)
442 			vgic_v4_get_vlpi_state(irq, &is_pending);
443 
444 		if (stored == is_pending)
445 			continue;
446 
447 		if (is_pending)
448 			val |= 1 << bit_nr;
449 		else
450 			val &= ~(1 << bit_nr);
451 
452 		ret = kvm_write_guest_lock(kvm, ptr, &val, 1);
453 		if (ret)
454 			goto out;
455 	}
456 
457 out:
458 	if (vlpi_avail)
459 		map_all_vpes(dist);
460 
461 	return ret;
462 }
463 
464 /**
465  * vgic_v3_rdist_overlap - check if a region overlaps with any
466  * existing redistributor region
467  *
468  * @kvm: kvm handle
469  * @base: base of the region
470  * @size: size of region
471  *
472  * Return: true if there is an overlap
473  */
474 bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size)
475 {
476 	struct vgic_dist *d = &kvm->arch.vgic;
477 	struct vgic_redist_region *rdreg;
478 
479 	list_for_each_entry(rdreg, &d->rd_regions, list) {
480 		if ((base + size > rdreg->base) &&
481 			(base < rdreg->base + vgic_v3_rd_region_size(kvm, rdreg)))
482 			return true;
483 	}
484 	return false;
485 }
486 
487 /*
488  * Check for overlapping regions and for regions crossing the end of memory
489  * for base addresses which have already been set.
490  */
491 bool vgic_v3_check_base(struct kvm *kvm)
492 {
493 	struct vgic_dist *d = &kvm->arch.vgic;
494 	struct vgic_redist_region *rdreg;
495 
496 	if (!IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) &&
497 	    d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
498 		return false;
499 
500 	list_for_each_entry(rdreg, &d->rd_regions, list) {
501 		if (rdreg->base + vgic_v3_rd_region_size(kvm, rdreg) <
502 			rdreg->base)
503 			return false;
504 	}
505 
506 	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base))
507 		return true;
508 
509 	return !vgic_v3_rdist_overlap(kvm, d->vgic_dist_base,
510 				      KVM_VGIC_V3_DIST_SIZE);
511 }
512 
513 /**
514  * vgic_v3_rdist_free_slot - Look up registered rdist regions and identify one
515  * which has free space to put a new rdist region.
516  *
517  * @rd_regions: redistributor region list head
518  *
519  * A redistributor regions maps n redistributors, n = region size / (2 x 64kB).
520  * Stride between redistributors is 0 and regions are filled in the index order.
521  *
522  * Return: the redist region handle, if any, that has space to map a new rdist
523  * region.
524  */
525 struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rd_regions)
526 {
527 	struct vgic_redist_region *rdreg;
528 
529 	list_for_each_entry(rdreg, rd_regions, list) {
530 		if (!vgic_v3_redist_region_full(rdreg))
531 			return rdreg;
532 	}
533 	return NULL;
534 }
535 
536 struct vgic_redist_region *vgic_v3_rdist_region_from_index(struct kvm *kvm,
537 							   u32 index)
538 {
539 	struct list_head *rd_regions = &kvm->arch.vgic.rd_regions;
540 	struct vgic_redist_region *rdreg;
541 
542 	list_for_each_entry(rdreg, rd_regions, list) {
543 		if (rdreg->index == index)
544 			return rdreg;
545 	}
546 	return NULL;
547 }
548 
549 
550 int vgic_v3_map_resources(struct kvm *kvm)
551 {
552 	struct vgic_dist *dist = &kvm->arch.vgic;
553 	struct kvm_vcpu *vcpu;
554 	int ret = 0;
555 	int c;
556 
557 	kvm_for_each_vcpu(c, vcpu, kvm) {
558 		struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
559 
560 		if (IS_VGIC_ADDR_UNDEF(vgic_cpu->rd_iodev.base_addr)) {
561 			kvm_debug("vcpu %d redistributor base not set\n", c);
562 			return -ENXIO;
563 		}
564 	}
565 
566 	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base)) {
567 		kvm_err("Need to set vgic distributor addresses first\n");
568 		return -ENXIO;
569 	}
570 
571 	if (!vgic_v3_check_base(kvm)) {
572 		kvm_err("VGIC redist and dist frames overlap\n");
573 		return -EINVAL;
574 	}
575 
576 	/*
577 	 * For a VGICv3 we require the userland to explicitly initialize
578 	 * the VGIC before we need to use it.
579 	 */
580 	if (!vgic_initialized(kvm)) {
581 		return -EBUSY;
582 	}
583 
584 	ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V3);
585 	if (ret) {
586 		kvm_err("Unable to register VGICv3 dist MMIO regions\n");
587 		return ret;
588 	}
589 
590 	if (kvm_vgic_global_state.has_gicv4_1)
591 		vgic_v4_configure_vsgis(kvm);
592 
593 	return 0;
594 }
595 
596 DEFINE_STATIC_KEY_FALSE(vgic_v3_cpuif_trap);
597 
598 static int __init early_group0_trap_cfg(char *buf)
599 {
600 	return strtobool(buf, &group0_trap);
601 }
602 early_param("kvm-arm.vgic_v3_group0_trap", early_group0_trap_cfg);
603 
604 static int __init early_group1_trap_cfg(char *buf)
605 {
606 	return strtobool(buf, &group1_trap);
607 }
608 early_param("kvm-arm.vgic_v3_group1_trap", early_group1_trap_cfg);
609 
610 static int __init early_common_trap_cfg(char *buf)
611 {
612 	return strtobool(buf, &common_trap);
613 }
614 early_param("kvm-arm.vgic_v3_common_trap", early_common_trap_cfg);
615 
616 static int __init early_gicv4_enable(char *buf)
617 {
618 	return strtobool(buf, &gicv4_enable);
619 }
620 early_param("kvm-arm.vgic_v4_enable", early_gicv4_enable);
621 
622 /**
623  * vgic_v3_probe - probe for a VGICv3 compatible interrupt controller
624  * @info:	pointer to the GIC description
625  *
626  * Returns 0 if the VGICv3 has been probed successfully, returns an error code
627  * otherwise
628  */
629 int vgic_v3_probe(const struct gic_kvm_info *info)
630 {
631 	u64 ich_vtr_el2 = kvm_call_hyp_ret(__vgic_v3_get_gic_config);
632 	bool has_v2;
633 	int ret;
634 
635 	has_v2 = ich_vtr_el2 >> 63;
636 	ich_vtr_el2 = (u32)ich_vtr_el2;
637 
638 	/*
639 	 * The ListRegs field is 5 bits, but there is an architectural
640 	 * maximum of 16 list registers. Just ignore bit 4...
641 	 */
642 	kvm_vgic_global_state.nr_lr = (ich_vtr_el2 & 0xf) + 1;
643 	kvm_vgic_global_state.can_emulate_gicv2 = false;
644 	kvm_vgic_global_state.ich_vtr_el2 = ich_vtr_el2;
645 
646 	/* GICv4 support? */
647 	if (info->has_v4) {
648 		kvm_vgic_global_state.has_gicv4 = gicv4_enable;
649 		kvm_vgic_global_state.has_gicv4_1 = info->has_v4_1 && gicv4_enable;
650 		kvm_info("GICv4%s support %sabled\n",
651 			 kvm_vgic_global_state.has_gicv4_1 ? ".1" : "",
652 			 gicv4_enable ? "en" : "dis");
653 	}
654 
655 	kvm_vgic_global_state.vcpu_base = 0;
656 
657 	if (!info->vcpu.start) {
658 		kvm_info("GICv3: no GICV resource entry\n");
659 	} else if (!has_v2) {
660 		pr_warn(FW_BUG "CPU interface incapable of MMIO access\n");
661 	} else if (!PAGE_ALIGNED(info->vcpu.start)) {
662 		pr_warn("GICV physical address 0x%llx not page aligned\n",
663 			(unsigned long long)info->vcpu.start);
664 	} else {
665 		kvm_vgic_global_state.vcpu_base = info->vcpu.start;
666 		kvm_vgic_global_state.can_emulate_gicv2 = true;
667 		ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
668 		if (ret) {
669 			kvm_err("Cannot register GICv2 KVM device.\n");
670 			return ret;
671 		}
672 		kvm_info("vgic-v2@%llx\n", info->vcpu.start);
673 	}
674 	ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V3);
675 	if (ret) {
676 		kvm_err("Cannot register GICv3 KVM device.\n");
677 		kvm_unregister_device_ops(KVM_DEV_TYPE_ARM_VGIC_V2);
678 		return ret;
679 	}
680 
681 	if (kvm_vgic_global_state.vcpu_base == 0)
682 		kvm_info("disabling GICv2 emulation\n");
683 
684 	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_30115)) {
685 		group0_trap = true;
686 		group1_trap = true;
687 	}
688 
689 	if (group0_trap || group1_trap || common_trap) {
690 		kvm_info("GICv3 sysreg trapping enabled ([%s%s%s], reduced performance)\n",
691 			 group0_trap ? "G0" : "",
692 			 group1_trap ? "G1" : "",
693 			 common_trap ? "C"  : "");
694 		static_branch_enable(&vgic_v3_cpuif_trap);
695 	}
696 
697 	kvm_vgic_global_state.vctrl_base = NULL;
698 	kvm_vgic_global_state.type = VGIC_V3;
699 	kvm_vgic_global_state.max_gic_vcpus = VGIC_V3_MAX_CPUS;
700 
701 	return 0;
702 }
703 
704 void vgic_v3_load(struct kvm_vcpu *vcpu)
705 {
706 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
707 
708 	/*
709 	 * If dealing with a GICv2 emulation on GICv3, VMCR_EL2.VFIQen
710 	 * is dependent on ICC_SRE_EL1.SRE, and we have to perform the
711 	 * VMCR_EL2 save/restore in the world switch.
712 	 */
713 	if (likely(cpu_if->vgic_sre))
714 		kvm_call_hyp(__vgic_v3_write_vmcr, cpu_if->vgic_vmcr);
715 
716 	kvm_call_hyp(__vgic_v3_restore_aprs, cpu_if);
717 
718 	if (has_vhe())
719 		__vgic_v3_activate_traps(cpu_if);
720 
721 	WARN_ON(vgic_v4_load(vcpu));
722 }
723 
724 void vgic_v3_vmcr_sync(struct kvm_vcpu *vcpu)
725 {
726 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
727 
728 	if (likely(cpu_if->vgic_sre))
729 		cpu_if->vgic_vmcr = kvm_call_hyp_ret(__vgic_v3_read_vmcr);
730 }
731 
732 void vgic_v3_put(struct kvm_vcpu *vcpu)
733 {
734 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
735 
736 	WARN_ON(vgic_v4_put(vcpu, false));
737 
738 	vgic_v3_vmcr_sync(vcpu);
739 
740 	kvm_call_hyp(__vgic_v3_save_aprs, cpu_if);
741 
742 	if (has_vhe())
743 		__vgic_v3_deactivate_traps(cpu_if);
744 }
745