summaryrefslogtreecommitdiffstats
path: root/virt/kvm/arm/vgic/vgic-v3.c
blob: df1503650300767f774e711fcadf98037f60fcfd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/irqchip/arm-gic-v3.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <kvm/arm_vgic.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_asm.h>

#include "vgic.h"

void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
{
	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;

	cpuif->vgic_hcr |= ICH_HCR_UIE;
}

static bool lr_signals_eoi_mi(u64 lr_val)
{
	return !(lr_val & ICH_LR_STATE) && (lr_val & ICH_LR_EOI) &&
	       !(lr_val & ICH_LR_HW);
}

void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
{
	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
	struct vgic_v3_cpu_if *cpuif = &vgic_cpu->vgic_v3;
	u32 model = vcpu->kvm->arch.vgic.vgic_model;
	int lr;

	cpuif->vgic_hcr &= ~ICH_HCR_UIE;

	for (lr = 0; lr < vgic_cpu->used_lrs; lr++) {
		u64 val = cpuif->vgic_lr[lr];
		u32 intid;
		struct vgic_irq *irq;

		if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
			intid = val & ICH_LR_VIRTUAL_ID_MASK;
		else
			intid = val & GICH_LR_VIRTUALID;

		/* Notify fds when the guest EOI'ed a level-triggered IRQ */
		if (lr_signals_eoi_mi(val) && vgic_valid_spi(vcpu->kvm, intid))
			kvm_notify_acked_irq(vcpu->kvm, 0,
					     intid - VGIC_NR_PRIVATE_IRQS);

		irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
		if (!irq)	/* An LPI could have been unmapped. */
			continue;

		spin_lock(&irq->irq_lock);

		/* Always preserve the active bit */
		irq->active = !!(val & ICH_LR_ACTIVE_BIT);

		/* Edge is the only case where we preserve the pending bit */
		if (irq->config == VGIC_CONFIG_EDGE &&
		    (val & ICH_LR_PENDING_BIT)) {
			irq->pending_latch = true;

			if (vgic_irq_is_sgi(intid) &&
			    model == KVM_DEV_TYPE_ARM_VGIC_V2) {
				u32 cpuid = val & GICH_LR_PHYSID_CPUID;

				cpuid >>= GICH_LR_PHYSID_CPUID_SHIFT;
				irq->source |= (1 << cpuid);
			}
		}

		/*
		 * Clear soft pending state when level irqs have been acked.
		 * Always regenerate the pending state.
		 */
		if (irq->config == VGIC_CONFIG_LEVEL) {
			if (!(val & ICH_LR_PENDING_BIT))
				irq->pending_latch = false;
		}

		spin_unlock(&irq->irq_lock);
		vgic_put_irq(vcpu->kvm, irq);
	}

	vgic_cpu->used_lrs = 0;
}

/* Requires the irq to be locked already */
void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
{
	u32 model = vcpu->kvm->arch.vgic.vgic_model;
	u64 val = irq->intid;

	if (irq_is_pending(irq)) {
		val |= ICH_LR_PENDING_BIT;

		if (irq->config == VGIC_CONFIG_EDGE)
			irq->pending_latch = false;

		if (vgic_irq_is_sgi(irq->intid) &&
		    model == KVM_DEV_TYPE_ARM_VGIC_V2) {
			u32 src = ffs(irq->source);

			BUG_ON(!src);
			val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT;
			irq->source &= ~(1 << (src - 1));
			if (irq->source)
				irq->pending_latch = true;
		}
	}

	if (irq->active)
		val |= ICH_LR_ACTIVE_BIT;

	if (irq->hw) {
		val |= ICH_LR_HW;
		val |= ((u64)irq->hwintid) << ICH_LR_PHYS_ID_SHIFT;
	} else {
		if (irq->config == VGIC_CONFIG_LEVEL)
			val |= ICH_LR_EOI;
	}

	/*
	 * We currently only support Group1 interrupts, which is a
	 * known defect. This needs to be addressed at some point.
	 */
	if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
		val |= ICH_LR_GROUP;

	val |= (u64)irq->priority << ICH_LR_PRIORITY_SHIFT;

	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = val;
}

void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
{
	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = 0;
}

void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
{
	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
	u32 vmcr;

	/*
	 * Ignore the FIQen bit, because GIC emulation always implies
	 * SRE=1 which means the vFIQEn bit is also RES1.
	 */
	vmcr = ((vmcrp->ctlr >> ICC_CTLR_EL1_EOImode_SHIFT) <<
		 ICH_VMCR_EOIM_SHIFT) & ICH_VMCR_EOIM_MASK;
	vmcr |= (vmcrp->ctlr << ICH_VMCR_CBPR_SHIFT) & ICH_VMCR_CBPR_MASK;
	vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
	vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
	vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
	vmcr |= (vmcrp->grpen0 << ICH_VMCR_ENG0_SHIFT) & ICH_VMCR_ENG0_MASK;
	vmcr |= (vmcrp->grpen1 << ICH_VMCR_ENG1_SHIFT) & ICH_VMCR_ENG1_MASK;

	cpu_if->vgic_vmcr = vmcr;
}

void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
{
	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
	u32 vmcr;

	vmcr = cpu_if->vgic_vmcr;

	/*
	 * Ignore the FIQen bit, because GIC emulation always implies
	 * SRE=1 which means the vFIQEn bit is also RES1.
	 */
	vmcrp->ctlr = ((vmcr >> ICH_VMCR_EOIM_SHIFT) <<
			ICC_CTLR_EL1_EOImode_SHIFT) & ICC_CTLR_EL1_EOImode_MASK;
	vmcrp->ctlr |= (vmcr & ICH_VMCR_CBPR_MASK) >> ICH_VMCR_CBPR_SHIFT;
	vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
	vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
	vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
	vmcrp->grpen0 = (vmcr & ICH_VMCR_ENG0_MASK) >> ICH_VMCR_ENG0_SHIFT;
	vmcrp->grpen1 = (vmcr & ICH_VMCR_ENG1_MASK) >> ICH_VMCR_ENG1_SHIFT;
}

#define INITIAL_PENDBASER_VALUE						  \
	(GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, RaWb)		| \
	GIC_BASER_CACHEABILITY(GICR_PENDBASER, OUTER, SameAsInner)	| \
	GIC_BASER_SHAREABILITY(GICR_PENDBASER, InnerShareable))

void vgic_v3_enable(struct kvm_vcpu *vcpu)
{
	struct vgic_v3_cpu_if *vgic_v3 = &vcpu->arch.vgic_cpu.vgic_v3;

	/*
	 * By forcing VMCR to zero, the GIC will restore the binary
	 * points to their reset values. Anything else resets to zero
	 * anyway.
	 */
	vgic_v3->vgic_vmcr = 0;
	vgic_v3->vgic_elrsr = ~0;

	/*
	 * If we are emulating a GICv3, we do it in an non-GICv2-compatible
	 * way, so we force SRE to 1 to demonstrate this to the guest.
	 * Also, we don't support any form of IRQ/FIQ bypass.
	 * This goes with the spec allowing the value to be RAO/WI.
	 */
	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
		vgic_v3->vgic_sre = (ICC_SRE_EL1_DIB |
				     ICC_SRE_EL1_DFB |
				     ICC_SRE_EL1_SRE);
		vcpu->arch.vgic_cpu.pendbaser = INITIAL_PENDBASER_VALUE;
	} else {
		vgic_v3->vgic_sre = 0;
	}

	vcpu->arch.vgic_cpu.num_id_bits = (kvm_vgic_global_state.ich_vtr_el2 &
					   ICH_VTR_ID_BITS_MASK) >>
					   ICH_VTR_ID_BITS_SHIFT;
	vcpu->arch.vgic_cpu.num_pri_bits = ((kvm_vgic_global_state.ich_vtr_el2 &
					    ICH_VTR_PRI_BITS_MASK) >>
					    ICH_VTR_PRI_BITS_SHIFT) + 1;

	/* Get the show on the road... */
	vgic_v3->vgic_hcr = ICH_HCR_EN;
}

/* check for overlapping regions and for regions crossing the end of memory */
static bool vgic_v3_check_base(struct kvm *kvm)
{
	struct vgic_dist *d = &kvm->arch.vgic;
	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;

	redist_size *= atomic_read(&kvm->online_vcpus);

	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
		return false;
	if (d->vgic_redist_base + redist_size < d->vgic_redist_base)
		return false;

	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= d->vgic_redist_base)
		return true;
	if (d->vgic_redist_base + redist_size <= d->vgic_dist_base)
		return true;

	return false;
}

int vgic_v3_map_resources(struct kvm *kvm)
{
	int ret = 0;
	struct vgic_dist *dist = &kvm->arch.vgic;

	if (vgic_ready(kvm))
		goto out;

	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
	    IS_VGIC_ADDR_UNDEF(dist->vgic_redist_base)) {
		kvm_err("Need to set vgic distributor addresses first\n");
		ret = -ENXIO;
		goto out;
	}

	if (!vgic_v3_check_base(kvm)) {
		kvm_err("VGIC redist and dist frames overlap\n");
		ret = -EINVAL;
		goto out;
	}

	/*
	 * For a VGICv3 we require the userland to explicitly initialize
	 * the VGIC before we need to use it.
	 */
	if (!vgic_initialized(kvm)) {
		ret = -EBUSY;
		goto out;
	}

	ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V3);
	if (ret) {
		kvm_err("Unable to register VGICv3 dist MMIO regions\n");
		goto out;
	}

	ret = vgic_register_redist_iodevs(kvm, dist->vgic_redist_base);
	if (ret) {
		kvm_err("Unable to register VGICv3 redist MMIO regions\n");
		goto out;
	}

	if (vgic_has_its(kvm)) {
		ret = vgic_register_its_iodevs(kvm);
		if (ret) {
			kvm_err("Unable to register VGIC ITS MMIO regions\n");
			goto out;
		}
	}

	dist->ready = true;

out:
	return ret;
}

/**
 * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
 * @node:	pointer to the DT node
 *
 * Returns 0 if a GICv3 has been found, returns an error code otherwise
 */
int vgic_v3_probe(const struct gic_kvm_info *info)
{
	u32 ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
	int ret;

	/*
	 * The ListRegs field is 5 bits, but there is a architectural
	 * maximum of 16 list registers. Just ignore bit 4...
	 */
	kvm_vgic_global_state.nr_lr = (ich_vtr_el2 & 0xf) + 1;
	kvm_vgic_global_state.can_emulate_gicv2 = false;
	kvm_vgic_global_state.ich_vtr_el2 = ich_vtr_el2;

	if (!info->vcpu.start) {
		kvm_info("GICv3: no GICV resource entry\n");
		kvm_vgic_global_state.vcpu_base = 0;
	} else if (!PAGE_ALIGNED(info->vcpu.start)) {
		pr_warn("GICV physical address 0x%llx not page aligned\n",
			(unsigned long long)info->vcpu.start);
		kvm_vgic_global_state.vcpu_base = 0;
	} else if (!PAGE_ALIGNED(resource_size(&info->vcpu))) {
		pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
			(unsigned long long)resource_size(&info->vcpu),
			PAGE_SIZE);
		kvm_vgic_global_state.vcpu_base = 0;
	} else {
		kvm_vgic_global_state.vcpu_base = info->vcpu.start;
		kvm_vgic_global_state.can_emulate_gicv2 = true;
		ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
		if (ret) {
			kvm_err("Cannot register GICv2 KVM device.\n");
			return ret;
		}
		kvm_info("vgic-v2@%llx\n", info->vcpu.start);
	}
	ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V3);
	if (ret) {
		kvm_err("Cannot register GICv3 KVM device.\n");
		kvm_unregister_device_ops(KVM_DEV_TYPE_ARM_VGIC_V2);
		return ret;
	}

	if (kvm_vgic_global_state.vcpu_base == 0)
		kvm_info("disabling GICv2 emulation\n");

	kvm_vgic_global_state.vctrl_base = NULL;
	kvm_vgic_global_state.type = VGIC_V3;
	kvm_vgic_global_state.max_gic_vcpus = VGIC_V3_MAX_CPUS;

	return 0;
}

void vgic_v3_load(struct kvm_vcpu *vcpu)
{
	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;

	/*
	 * If dealing with a GICv2 emulation on GICv3, VMCR_EL2.VFIQen
	 * is dependent on ICC_SRE_EL1.SRE, and we have to perform the
	 * VMCR_EL2 save/restore in the world switch.
	 */
	if (likely(cpu_if->vgic_sre))
		kvm_call_hyp(__vgic_v3_write_vmcr, cpu_if->vgic_vmcr);
}

void vgic_v3_put(struct kvm_vcpu *vcpu)
{
	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;

	if (likely(cpu_if->vgic_sre))
		cpu_if->vgic_vmcr = kvm_call_hyp(__vgic_v3_read_vmcr);
}
OpenPOWER on IntegriCloud