virt/kvm/arm/vgic-v3.c

   1 /*
   2  * Copyright (C) 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-v3.h>
  28
  29 #include <asm/kvm_emulate.h>
  30 #include <asm/kvm_arm.h>
  31 #include <asm/kvm_mmu.h>
  32
  33 /* These are for GICv2 emulation only */
  34 #define GICH_LR_VIRTUALID               (0x3ffUL << 0)
  35 #define GICH_LR_PHYSID_CPUID_SHIFT      (10)
  36 #define GICH_LR_PHYSID_CPUID            (7UL << GICH_LR_PHYSID_CPUID_SHIFT)
  37
  38 /*
  39  * LRs are stored in reverse order in memory. make sure we index them
  40  * correctly.
  41  */
  42 #define LR_INDEX(lr)                    (VGIC_V3_MAX_LRS - 1 - lr)
  43
  44 static u32 ich_vtr_el2;
  45
  46 static struct vgic_lr vgic_v3_get_lr(const struct kvm_vcpu *vcpu, int lr)
  47 {
  48         struct vgic_lr lr_desc;
  49         u64 val = vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)];
  50
  51         lr_desc.irq     = val & GICH_LR_VIRTUALID;
  52         if (lr_desc.irq <= 15)
  53                 lr_desc.source  = (val >> GICH_LR_PHYSID_CPUID_SHIFT) & 0x7;
  54         else
  55                 lr_desc.source = 0;
  56         lr_desc.state   = 0;
  57
  58         if (val & ICH_LR_PENDING_BIT)
  59                 lr_desc.state |= LR_STATE_PENDING;
  60         if (val & ICH_LR_ACTIVE_BIT)
  61                 lr_desc.state |= LR_STATE_ACTIVE;
  62         if (val & ICH_LR_EOI)
  63                 lr_desc.state |= LR_EOI_INT;
  64
  65         return lr_desc;
  66 }
  67
  68 static void vgic_v3_set_lr(struct kvm_vcpu *vcpu, int lr,
  69                            struct vgic_lr lr_desc)
  70 {
  71         u64 lr_val = (((u32)lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT) |
  72                       lr_desc.irq);
  73
  74         if (lr_desc.state & LR_STATE_PENDING)
  75                 lr_val |= ICH_LR_PENDING_BIT;
  76         if (lr_desc.state & LR_STATE_ACTIVE)
  77                 lr_val |= ICH_LR_ACTIVE_BIT;
  78         if (lr_desc.state & LR_EOI_INT)
  79                 lr_val |= ICH_LR_EOI;
  80
  81         vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)] = lr_val;
  82 }
  83
  84 static void vgic_v3_sync_lr_elrsr(struct kvm_vcpu *vcpu, int lr,
  85                                   struct vgic_lr lr_desc)
  86 {
  87         if (!(lr_desc.state & LR_STATE_MASK))
  88                 vcpu->arch.vgic_cpu.vgic_v3.vgic_elrsr |= (1U << lr);
  89 }
  90
  91 static u64 vgic_v3_get_elrsr(const struct kvm_vcpu *vcpu)
  92 {
  93         return vcpu->arch.vgic_cpu.vgic_v3.vgic_elrsr;
  94 }
  95
  96 static u64 vgic_v3_get_eisr(const struct kvm_vcpu *vcpu)
  97 {
  98         return vcpu->arch.vgic_cpu.vgic_v3.vgic_eisr;
  99 }
 100
 101 static u32 vgic_v3_get_interrupt_status(const struct kvm_vcpu *vcpu)
 102 {
 103         u32 misr = vcpu->arch.vgic_cpu.vgic_v3.vgic_misr;
 104         u32 ret = 0;
 105
 106         if (misr & ICH_MISR_EOI)
 107                 ret |= INT_STATUS_EOI;
 108         if (misr & ICH_MISR_U)
 109                 ret |= INT_STATUS_UNDERFLOW;
 110
 111         return ret;
 112 }
 113
 114 static void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
 115 {
 116         u32 vmcr = vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr;
 117
 118         vmcrp->ctlr = (vmcr & ICH_VMCR_CTLR_MASK) >> ICH_VMCR_CTLR_SHIFT;
 119         vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
 120         vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
 121         vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
 122 }
 123
 124 static void vgic_v3_enable_underflow(struct kvm_vcpu *vcpu)
 125 {
 126         vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr |= ICH_HCR_UIE;
 127 }
 128
 129 static void vgic_v3_disable_underflow(struct kvm_vcpu *vcpu)
 130 {
 131         vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr &= ~ICH_HCR_UIE;
 132 }
 133
 134 static void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
 135 {
 136         u32 vmcr;
 137
 138         vmcr  = (vmcrp->ctlr << ICH_VMCR_CTLR_SHIFT) & ICH_VMCR_CTLR_MASK;
 139         vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
 140         vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
 141         vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
 142
 143         vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = vmcr;
 144 }
 145
 146 static void vgic_v3_enable(struct kvm_vcpu *vcpu)
 147 {
 148         /*
 149          * By forcing VMCR to zero, the GIC will restore the binary
 150          * points to their reset values. Anything else resets to zero
 151          * anyway.
 152          */
 153         vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = 0;
 154
 155         /* Get the show on the road... */
 156         vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr = ICH_HCR_EN;
 157 }
 158
 159 static const struct vgic_ops vgic_v3_ops = {
 160         .get_lr                 = vgic_v3_get_lr,
 161         .set_lr                 = vgic_v3_set_lr,
 162         .sync_lr_elrsr          = vgic_v3_sync_lr_elrsr,
 163         .get_elrsr              = vgic_v3_get_elrsr,
 164         .get_eisr               = vgic_v3_get_eisr,
 165         .get_interrupt_status   = vgic_v3_get_interrupt_status,
 166         .enable_underflow       = vgic_v3_enable_underflow,
 167         .disable_underflow      = vgic_v3_disable_underflow,
 168         .get_vmcr               = vgic_v3_get_vmcr,
 169         .set_vmcr               = vgic_v3_set_vmcr,
 170         .enable                 = vgic_v3_enable,
 171 };
 172
 173 static struct vgic_params vgic_v3_params;
 174
 175 /**
 176  * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
 177  * @node:       pointer to the DT node
 178  * @ops:        address of a pointer to the GICv3 operations
 179  * @params:     address of a pointer to HW-specific parameters
 180  *
 181  * Returns 0 if a GICv3 has been found, with the low level operations
 182  * in *ops and the HW parameters in *params. Returns an error code
 183  * otherwise.
 184  */
 185 int vgic_v3_probe(struct device_node *vgic_node,
 186                   const struct vgic_ops **ops,
 187                   const struct vgic_params **params)
 188 {
 189         int ret = 0;
 190         u32 gicv_idx;
 191         struct resource vcpu_res;
 192         struct vgic_params *vgic = &vgic_v3_params;
 193
 194         vgic->maint_irq = irq_of_parse_and_map(vgic_node, 0);
 195         if (!vgic->maint_irq) {
 196                 kvm_err("error getting vgic maintenance irq from DT\n");
 197                 ret = -ENXIO;
 198                 goto out;
 199         }
 200
 201         ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
 202
 203         /*
 204          * The ListRegs field is 5 bits, but there is a architectural
 205          * maximum of 16 list registers. Just ignore bit 4...
 206          */
 207         vgic->nr_lr = (ich_vtr_el2 & 0xf) + 1;
 208
 209         if (of_property_read_u32(vgic_node, "#redistributor-regions", &gicv_idx))
 210                 gicv_idx = 1;
 211
 212         gicv_idx += 3; /* Also skip GICD, GICC, GICH */
 213         if (of_address_to_resource(vgic_node, gicv_idx, &vcpu_res)) {
 214                 kvm_err("Cannot obtain GICV region\n");
 215                 ret = -ENXIO;
 216                 goto out;
 217         }
 218
 219         if (!PAGE_ALIGNED(vcpu_res.start)) {
 220                 kvm_err("GICV physical address 0x%llx not page aligned\n",
 221                         (unsigned long long)vcpu_res.start);
 222                 ret = -ENXIO;
 223                 goto out;
 224         }
 225
 226         if (!PAGE_ALIGNED(resource_size(&vcpu_res))) {
 227                 kvm_err("GICV size 0x%llx not a multiple of page size 0x%lx\n",
 228                         (unsigned long long)resource_size(&vcpu_res),
 229                         PAGE_SIZE);
 230                 ret = -ENXIO;
 231                 goto out;
 232         }
 233
 234         vgic->vcpu_base = vcpu_res.start;
 235         vgic->vctrl_base = NULL;
 236         vgic->type = VGIC_V3;
 237
 238         kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
 239                  vcpu_res.start, vgic->maint_irq);
 240
 241         *ops = &vgic_v3_ops;
 242         *params = vgic;
 243
 244 out:
 245         of_node_put(vgic_node);
 246         return ret;
 247 }