tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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_emulate.h>
23#include <asm/kvm_hyp.h>
24
25static void __hyp_text save_elrsr(struct kvm_vcpu *vcpu, 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 elrsr0, elrsr1;
30
31 elrsr0 = readl_relaxed(base + GICH_ELRSR0);
32 if (unlikely(nr_lr > 32))
33 elrsr1 = readl_relaxed(base + GICH_ELRSR1);
34 else
35 elrsr1 = 0;
36
37#ifdef CONFIG_CPU_BIG_ENDIAN
38 cpu_if->vgic_elrsr = ((u64)elrsr0 << 32) | elrsr1;
39#else
40 cpu_if->vgic_elrsr = ((u64)elrsr1 << 32) | elrsr0;
41#endif
42}
43
44static void __hyp_text save_lrs(struct kvm_vcpu *vcpu, void __iomem *base)
45{
46 struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
47 int i;
48 u64 used_lrs = vcpu->arch.vgic_cpu.used_lrs;
49
50 for (i = 0; i < used_lrs; i++) {
51 if (cpu_if->vgic_elrsr & (1UL << i))
52 cpu_if->vgic_lr[i] &= ~GICH_LR_STATE;
53 else
54 cpu_if->vgic_lr[i] = readl_relaxed(base + GICH_LR0 + (i * 4));
55
56 writel_relaxed(0, base + GICH_LR0 + (i * 4));
57 }
58}
59
60/* vcpu is already in the HYP VA space */
61void __hyp_text __vgic_v2_save_state(struct kvm_vcpu *vcpu)
62{
63 struct kvm *kvm = kern_hyp_va(vcpu->kvm);
64 struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
65 struct vgic_dist *vgic = &kvm->arch.vgic;
66 void __iomem *base = kern_hyp_va(vgic->vctrl_base);
67 u64 used_lrs = vcpu->arch.vgic_cpu.used_lrs;
68
69 if (!base)
70 return;
71
72 if (used_lrs) {
73 cpu_if->vgic_apr = readl_relaxed(base + GICH_APR);
74
75 save_elrsr(vcpu, base);
76 save_lrs(vcpu, base);
77
78 writel_relaxed(0, base + GICH_HCR);
79 } else {
80 cpu_if->vgic_elrsr = ~0UL;
81 cpu_if->vgic_apr = 0;
82 }
83}
84
85/* vcpu is already in the HYP VA space */
86void __hyp_text __vgic_v2_restore_state(struct kvm_vcpu *vcpu)
87{
88 struct kvm *kvm = kern_hyp_va(vcpu->kvm);
89 struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
90 struct vgic_dist *vgic = &kvm->arch.vgic;
91 void __iomem *base = kern_hyp_va(vgic->vctrl_base);
92 int i;
93 u64 used_lrs = vcpu->arch.vgic_cpu.used_lrs;
94
95 if (!base)
96 return;
97
98 if (used_lrs) {
99 writel_relaxed(cpu_if->vgic_hcr, base + GICH_HCR);
100 writel_relaxed(cpu_if->vgic_apr, base + GICH_APR);
101 for (i = 0; i < used_lrs; i++) {
102 writel_relaxed(cpu_if->vgic_lr[i],
103 base + GICH_LR0 + (i * 4));
104 }
105 }
106}
107
108#ifdef CONFIG_ARM64
109/*
110 * __vgic_v2_perform_cpuif_access -- perform a GICV access on behalf of the
111 * guest.
112 *
113 * @vcpu: the offending vcpu
114 *
115 * Returns:
116 * 1: GICV access successfully performed
117 * 0: Not a GICV access
118 * -1: Illegal GICV access
119 */
120int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
121{
122 struct kvm *kvm = kern_hyp_va(vcpu->kvm);
123 struct vgic_dist *vgic = &kvm->arch.vgic;
124 phys_addr_t fault_ipa;
125 void __iomem *addr;
126 int rd;
127
128 /* Build the full address */
129 fault_ipa = kvm_vcpu_get_fault_ipa(vcpu);
130 fault_ipa |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0);
131
132 /* If not for GICV, move on */
133 if (fault_ipa < vgic->vgic_cpu_base ||
134 fault_ipa >= (vgic->vgic_cpu_base + KVM_VGIC_V2_CPU_SIZE))
135 return 0;
136
137 /* Reject anything but a 32bit access */
138 if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32))
139 return -1;
140
141 /* Not aligned? Don't bother */
142 if (fault_ipa & 3)
143 return -1;
144
145 rd = kvm_vcpu_dabt_get_rd(vcpu);
146 addr = kern_hyp_va((kern_hyp_va(&kvm_vgic_global_state))->vcpu_base_va);
147 addr += fault_ipa - vgic->vgic_cpu_base;
148
149 if (kvm_vcpu_dabt_iswrite(vcpu)) {
150 u32 data = vcpu_data_guest_to_host(vcpu,
151 vcpu_get_reg(vcpu, rd),
152 sizeof(u32));
153 writel_relaxed(data, addr);
154 } else {
155 u32 data = readl_relaxed(addr);
156 vcpu_set_reg(vcpu, rd, vcpu_data_host_to_guest(vcpu, data,
157 sizeof(u32)));
158 }
159
160 return 1;
161}
162#endif