arm/arm64: KVM: Fix unaligned access bug on gicv2 access
[deliverable/linux.git] / virt / kvm / arm / vgic-v2.c
1 /*
2 * Copyright (C) 2012,2013 ARM Limited, All Rights Reserved.
3 * Author: Marc Zyngier <marc.zyngier@arm.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 */
17
18 #include <linux/cpu.h>
19 #include <linux/kvm.h>
20 #include <linux/kvm_host.h>
21 #include <linux/interrupt.h>
22 #include <linux/io.h>
23 #include <linux/of.h>
24 #include <linux/of_address.h>
25 #include <linux/of_irq.h>
26
27 #include <linux/irqchip/arm-gic.h>
28
29 #include <asm/kvm_emulate.h>
30 #include <asm/kvm_arm.h>
31 #include <asm/kvm_mmu.h>
32
33 static struct vgic_lr vgic_v2_get_lr(const struct kvm_vcpu *vcpu, int lr)
34 {
35 struct vgic_lr lr_desc;
36 u32 val = vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr];
37
38 lr_desc.irq = val & GICH_LR_VIRTUALID;
39 if (lr_desc.irq <= 15)
40 lr_desc.source = (val >> GICH_LR_PHYSID_CPUID_SHIFT) & 0x7;
41 else
42 lr_desc.source = 0;
43 lr_desc.state = 0;
44
45 if (val & GICH_LR_PENDING_BIT)
46 lr_desc.state |= LR_STATE_PENDING;
47 if (val & GICH_LR_ACTIVE_BIT)
48 lr_desc.state |= LR_STATE_ACTIVE;
49 if (val & GICH_LR_EOI)
50 lr_desc.state |= LR_EOI_INT;
51
52 return lr_desc;
53 }
54
55 static void vgic_v2_set_lr(struct kvm_vcpu *vcpu, int lr,
56 struct vgic_lr lr_desc)
57 {
58 u32 lr_val = (lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT) | lr_desc.irq;
59
60 if (lr_desc.state & LR_STATE_PENDING)
61 lr_val |= GICH_LR_PENDING_BIT;
62 if (lr_desc.state & LR_STATE_ACTIVE)
63 lr_val |= GICH_LR_ACTIVE_BIT;
64 if (lr_desc.state & LR_EOI_INT)
65 lr_val |= GICH_LR_EOI;
66
67 vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr] = lr_val;
68 }
69
70 static void vgic_v2_sync_lr_elrsr(struct kvm_vcpu *vcpu, int lr,
71 struct vgic_lr lr_desc)
72 {
73 if (!(lr_desc.state & LR_STATE_MASK))
74 __set_bit(lr, (unsigned long *)vcpu->arch.vgic_cpu.vgic_v2.vgic_elrsr);
75 }
76
77 static u64 vgic_v2_get_elrsr(const struct kvm_vcpu *vcpu)
78 {
79 u64 val;
80
81 #if BITS_PER_LONG == 64
82 val = vcpu->arch.vgic_cpu.vgic_v2.vgic_elrsr[1];
83 val <<= 32;
84 val |= vcpu->arch.vgic_cpu.vgic_v2.vgic_elrsr[0];
85 #else
86 val = *(u64 *)vcpu->arch.vgic_cpu.vgic_v2.vgic_elrsr;
87 #endif
88 return val;
89 }
90
91 static u64 vgic_v2_get_eisr(const struct kvm_vcpu *vcpu)
92 {
93 u64 val;
94
95 #if BITS_PER_LONG == 64
96 val = vcpu->arch.vgic_cpu.vgic_v2.vgic_eisr[1];
97 val <<= 32;
98 val |= vcpu->arch.vgic_cpu.vgic_v2.vgic_eisr[0];
99 #else
100 val = *(u64 *)vcpu->arch.vgic_cpu.vgic_v2.vgic_eisr;
101 #endif
102 return val;
103 }
104
105 static u32 vgic_v2_get_interrupt_status(const struct kvm_vcpu *vcpu)
106 {
107 u32 misr = vcpu->arch.vgic_cpu.vgic_v2.vgic_misr;
108 u32 ret = 0;
109
110 if (misr & GICH_MISR_EOI)
111 ret |= INT_STATUS_EOI;
112 if (misr & GICH_MISR_U)
113 ret |= INT_STATUS_UNDERFLOW;
114
115 return ret;
116 }
117
118 static void vgic_v2_enable_underflow(struct kvm_vcpu *vcpu)
119 {
120 vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr |= GICH_HCR_UIE;
121 }
122
123 static void vgic_v2_disable_underflow(struct kvm_vcpu *vcpu)
124 {
125 vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr &= ~GICH_HCR_UIE;
126 }
127
128 static void vgic_v2_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
129 {
130 u32 vmcr = vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr;
131
132 vmcrp->ctlr = (vmcr & GICH_VMCR_CTRL_MASK) >> GICH_VMCR_CTRL_SHIFT;
133 vmcrp->abpr = (vmcr & GICH_VMCR_ALIAS_BINPOINT_MASK) >> GICH_VMCR_ALIAS_BINPOINT_SHIFT;
134 vmcrp->bpr = (vmcr & GICH_VMCR_BINPOINT_MASK) >> GICH_VMCR_BINPOINT_SHIFT;
135 vmcrp->pmr = (vmcr & GICH_VMCR_PRIMASK_MASK) >> GICH_VMCR_PRIMASK_SHIFT;
136 }
137
138 static void vgic_v2_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
139 {
140 u32 vmcr;
141
142 vmcr = (vmcrp->ctlr << GICH_VMCR_CTRL_SHIFT) & GICH_VMCR_CTRL_MASK;
143 vmcr |= (vmcrp->abpr << GICH_VMCR_ALIAS_BINPOINT_SHIFT) & GICH_VMCR_ALIAS_BINPOINT_MASK;
144 vmcr |= (vmcrp->bpr << GICH_VMCR_BINPOINT_SHIFT) & GICH_VMCR_BINPOINT_MASK;
145 vmcr |= (vmcrp->pmr << GICH_VMCR_PRIMASK_SHIFT) & GICH_VMCR_PRIMASK_MASK;
146
147 vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = vmcr;
148 }
149
150 static void vgic_v2_enable(struct kvm_vcpu *vcpu)
151 {
152 /*
153 * By forcing VMCR to zero, the GIC will restore the binary
154 * points to their reset values. Anything else resets to zero
155 * anyway.
156 */
157 vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = 0;
158
159 /* Get the show on the road... */
160 vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr = GICH_HCR_EN;
161 }
162
163 static const struct vgic_ops vgic_v2_ops = {
164 .get_lr = vgic_v2_get_lr,
165 .set_lr = vgic_v2_set_lr,
166 .sync_lr_elrsr = vgic_v2_sync_lr_elrsr,
167 .get_elrsr = vgic_v2_get_elrsr,
168 .get_eisr = vgic_v2_get_eisr,
169 .get_interrupt_status = vgic_v2_get_interrupt_status,
170 .enable_underflow = vgic_v2_enable_underflow,
171 .disable_underflow = vgic_v2_disable_underflow,
172 .get_vmcr = vgic_v2_get_vmcr,
173 .set_vmcr = vgic_v2_set_vmcr,
174 .enable = vgic_v2_enable,
175 };
176
177 static struct vgic_params vgic_v2_params;
178
179 /**
180 * vgic_v2_probe - probe for a GICv2 compatible interrupt controller in DT
181 * @node: pointer to the DT node
182 * @ops: address of a pointer to the GICv2 operations
183 * @params: address of a pointer to HW-specific parameters
184 *
185 * Returns 0 if a GICv2 has been found, with the low level operations
186 * in *ops and the HW parameters in *params. Returns an error code
187 * otherwise.
188 */
189 int vgic_v2_probe(struct device_node *vgic_node,
190 const struct vgic_ops **ops,
191 const struct vgic_params **params)
192 {
193 int ret;
194 struct resource vctrl_res;
195 struct resource vcpu_res;
196 struct vgic_params *vgic = &vgic_v2_params;
197
198 vgic->maint_irq = irq_of_parse_and_map(vgic_node, 0);
199 if (!vgic->maint_irq) {
200 kvm_err("error getting vgic maintenance irq from DT\n");
201 ret = -ENXIO;
202 goto out;
203 }
204
205 ret = of_address_to_resource(vgic_node, 2, &vctrl_res);
206 if (ret) {
207 kvm_err("Cannot obtain GICH resource\n");
208 goto out;
209 }
210
211 vgic->vctrl_base = of_iomap(vgic_node, 2);
212 if (!vgic->vctrl_base) {
213 kvm_err("Cannot ioremap GICH\n");
214 ret = -ENOMEM;
215 goto out;
216 }
217
218 vgic->nr_lr = readl_relaxed(vgic->vctrl_base + GICH_VTR);
219 vgic->nr_lr = (vgic->nr_lr & 0x3f) + 1;
220
221 ret = create_hyp_io_mappings(vgic->vctrl_base,
222 vgic->vctrl_base + resource_size(&vctrl_res),
223 vctrl_res.start);
224 if (ret) {
225 kvm_err("Cannot map VCTRL into hyp\n");
226 goto out_unmap;
227 }
228
229 if (of_address_to_resource(vgic_node, 3, &vcpu_res)) {
230 kvm_err("Cannot obtain GICV resource\n");
231 ret = -ENXIO;
232 goto out_unmap;
233 }
234
235 if (!PAGE_ALIGNED(vcpu_res.start)) {
236 kvm_err("GICV physical address 0x%llx not page aligned\n",
237 (unsigned long long)vcpu_res.start);
238 ret = -ENXIO;
239 goto out_unmap;
240 }
241
242 if (!PAGE_ALIGNED(resource_size(&vcpu_res))) {
243 kvm_err("GICV size 0x%llx not a multiple of page size 0x%lx\n",
244 (unsigned long long)resource_size(&vcpu_res),
245 PAGE_SIZE);
246 ret = -ENXIO;
247 goto out_unmap;
248 }
249
250 vgic->vcpu_base = vcpu_res.start;
251
252 kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
253 vctrl_res.start, vgic->maint_irq);
254
255 vgic->type = VGIC_V2;
256 *ops = &vgic_v2_ops;
257 *params = vgic;
258 goto out;
259
260 out_unmap:
261 iounmap(vgic->vctrl_base);
262 out:
263 of_node_put(vgic_node);
264 return ret;
265 }
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