arm64: KVM: vgic-v2: Add the GICV emulation infrastructure
[cascardo/linux.git] / virt / kvm / arm / hyp / vgic-v2-sr.c
1 /*
2  * Copyright (C) 2012-2015 - ARM Ltd
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/compiler.h>
19 #include <linux/irqchip/arm-gic.h>
20 #include <linux/kvm_host.h>
21
22 #include <asm/kvm_hyp.h>
23
24 static void __hyp_text save_maint_int_state(struct kvm_vcpu *vcpu,
25                                             void __iomem *base)
26 {
27         struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
28         int nr_lr = (kern_hyp_va(&kvm_vgic_global_state))->nr_lr;
29         u32 eisr0, eisr1;
30         int i;
31         bool expect_mi;
32
33         expect_mi = !!(cpu_if->vgic_hcr & GICH_HCR_UIE);
34
35         for (i = 0; i < nr_lr; i++) {
36                 if (!(vcpu->arch.vgic_cpu.live_lrs & (1UL << i)))
37                                 continue;
38
39                 expect_mi |= (!(cpu_if->vgic_lr[i] & GICH_LR_HW) &&
40                               (cpu_if->vgic_lr[i] & GICH_LR_EOI));
41         }
42
43         if (expect_mi) {
44                 cpu_if->vgic_misr = readl_relaxed(base + GICH_MISR);
45
46                 if (cpu_if->vgic_misr & GICH_MISR_EOI) {
47                         eisr0  = readl_relaxed(base + GICH_EISR0);
48                         if (unlikely(nr_lr > 32))
49                                 eisr1  = readl_relaxed(base + GICH_EISR1);
50                         else
51                                 eisr1 = 0;
52                 } else {
53                         eisr0 = eisr1 = 0;
54                 }
55         } else {
56                 cpu_if->vgic_misr = 0;
57                 eisr0 = eisr1 = 0;
58         }
59
60 #ifdef CONFIG_CPU_BIG_ENDIAN
61         cpu_if->vgic_eisr = ((u64)eisr0 << 32) | eisr1;
62 #else
63         cpu_if->vgic_eisr = ((u64)eisr1 << 32) | eisr0;
64 #endif
65 }
66
67 static void __hyp_text save_elrsr(struct kvm_vcpu *vcpu, void __iomem *base)
68 {
69         struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
70         int nr_lr = (kern_hyp_va(&kvm_vgic_global_state))->nr_lr;
71         u32 elrsr0, elrsr1;
72
73         elrsr0 = readl_relaxed(base + GICH_ELRSR0);
74         if (unlikely(nr_lr > 32))
75                 elrsr1 = readl_relaxed(base + GICH_ELRSR1);
76         else
77                 elrsr1 = 0;
78
79 #ifdef CONFIG_CPU_BIG_ENDIAN
80         cpu_if->vgic_elrsr = ((u64)elrsr0 << 32) | elrsr1;
81 #else
82         cpu_if->vgic_elrsr = ((u64)elrsr1 << 32) | elrsr0;
83 #endif
84 }
85
86 static void __hyp_text save_lrs(struct kvm_vcpu *vcpu, void __iomem *base)
87 {
88         struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
89         int nr_lr = (kern_hyp_va(&kvm_vgic_global_state))->nr_lr;
90         int i;
91
92         for (i = 0; i < nr_lr; i++) {
93                 if (!(vcpu->arch.vgic_cpu.live_lrs & (1UL << i)))
94                         continue;
95
96                 if (cpu_if->vgic_elrsr & (1UL << i))
97                         cpu_if->vgic_lr[i] &= ~GICH_LR_STATE;
98                 else
99                         cpu_if->vgic_lr[i] = readl_relaxed(base + GICH_LR0 + (i * 4));
100
101                 writel_relaxed(0, base + GICH_LR0 + (i * 4));
102         }
103 }
104
105 /* vcpu is already in the HYP VA space */
106 void __hyp_text __vgic_v2_save_state(struct kvm_vcpu *vcpu)
107 {
108         struct kvm *kvm = kern_hyp_va(vcpu->kvm);
109         struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
110         struct vgic_dist *vgic = &kvm->arch.vgic;
111         void __iomem *base = kern_hyp_va(vgic->vctrl_base);
112
113         if (!base)
114                 return;
115
116         cpu_if->vgic_vmcr = readl_relaxed(base + GICH_VMCR);
117
118         if (vcpu->arch.vgic_cpu.live_lrs) {
119                 cpu_if->vgic_apr = readl_relaxed(base + GICH_APR);
120
121                 save_maint_int_state(vcpu, base);
122                 save_elrsr(vcpu, base);
123                 save_lrs(vcpu, base);
124
125                 writel_relaxed(0, base + GICH_HCR);
126
127                 vcpu->arch.vgic_cpu.live_lrs = 0;
128         } else {
129                 cpu_if->vgic_eisr = 0;
130                 cpu_if->vgic_elrsr = ~0UL;
131                 cpu_if->vgic_misr = 0;
132                 cpu_if->vgic_apr = 0;
133         }
134 }
135
136 /* vcpu is already in the HYP VA space */
137 void __hyp_text __vgic_v2_restore_state(struct kvm_vcpu *vcpu)
138 {
139         struct kvm *kvm = kern_hyp_va(vcpu->kvm);
140         struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
141         struct vgic_dist *vgic = &kvm->arch.vgic;
142         void __iomem *base = kern_hyp_va(vgic->vctrl_base);
143         int nr_lr = (kern_hyp_va(&kvm_vgic_global_state))->nr_lr;
144         int i;
145         u64 live_lrs = 0;
146
147         if (!base)
148                 return;
149
150
151         for (i = 0; i < nr_lr; i++)
152                 if (cpu_if->vgic_lr[i] & GICH_LR_STATE)
153                         live_lrs |= 1UL << i;
154
155         if (live_lrs) {
156                 writel_relaxed(cpu_if->vgic_hcr, base + GICH_HCR);
157                 writel_relaxed(cpu_if->vgic_apr, base + GICH_APR);
158                 for (i = 0; i < nr_lr; i++) {
159                         if (!(live_lrs & (1UL << i)))
160                                 continue;
161
162                         writel_relaxed(cpu_if->vgic_lr[i],
163                                        base + GICH_LR0 + (i * 4));
164                 }
165         }
166
167         writel_relaxed(cpu_if->vgic_vmcr, base + GICH_VMCR);
168         vcpu->arch.vgic_cpu.live_lrs = live_lrs;
169 }
170
171 #ifdef CONFIG_ARM64
172 bool __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
173 {
174                 return false;
175 }
176 #endif