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_emulate.h>
  23 #include <asm/kvm_hyp.h>
  24
  25 static 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
  44 static 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 */
  61 void __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 */
  86 void __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  */
 120 int __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