hw/intc/arm_gic_kvm.c

   1 /*
   2  * ARM Generic Interrupt Controller using KVM in-kernel support
   3  *
   4  * Copyright (c) 2012 Linaro Limited
   5  * Written by Peter Maydell
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "hw/sysbus.h"
  22 #include "sysemu/kvm.h"
  23 #include "kvm_arm.h"
  24 #include "gic_internal.h"
  25
  26 #define TYPE_KVM_ARM_GIC "kvm-arm-gic"
  27 #define KVM_ARM_GIC(obj) \
  28      OBJECT_CHECK(GICState, (obj), TYPE_KVM_ARM_GIC)
  29 #define KVM_ARM_GIC_CLASS(klass) \
  30      OBJECT_CLASS_CHECK(KVMARMGICClass, (klass), TYPE_KVM_ARM_GIC)
  31 #define KVM_ARM_GIC_GET_CLASS(obj) \
  32      OBJECT_GET_CLASS(KVMARMGICClass, (obj), TYPE_KVM_ARM_GIC)
  33
  34 typedef struct KVMARMGICClass {
  35     ARMGICCommonClass parent_class;
  36     DeviceRealize parent_realize;
  37     void (*parent_reset)(DeviceState *dev);
  38 } KVMARMGICClass;
  39
  40 static void kvm_arm_gic_set_irq(void *opaque, int irq, int level)
  41 {
  42     /* Meaning of the 'irq' parameter:
  43      *  [0..N-1] : external interrupts
  44      *  [N..N+31] : PPI (internal) interrupts for CPU 0
  45      *  [N+32..N+63] : PPI (internal interrupts for CPU 1
  46      *  ...
  47      * Convert this to the kernel's desired encoding, which
  48      * has separate fields in the irq number for type,
  49      * CPU number and interrupt number.
  50      */
  51     GICState *s = (GICState *)opaque;
  52     int kvm_irq, irqtype, cpu;
  53
  54     if (irq < (s->num_irq - GIC_INTERNAL)) {
  55         /* External interrupt. The kernel numbers these like the GIC
  56          * hardware, with external interrupt IDs starting after the
  57          * internal ones.
  58          */
  59         irqtype = KVM_ARM_IRQ_TYPE_SPI;
  60         cpu = 0;
  61         irq += GIC_INTERNAL;
  62     } else {
  63         /* Internal interrupt: decode into (cpu, interrupt id) */
  64         irqtype = KVM_ARM_IRQ_TYPE_PPI;
  65         irq -= (s->num_irq - GIC_INTERNAL);
  66         cpu = irq / GIC_INTERNAL;
  67         irq %= GIC_INTERNAL;
  68     }
  69     kvm_irq = (irqtype << KVM_ARM_IRQ_TYPE_SHIFT)
  70         | (cpu << KVM_ARM_IRQ_VCPU_SHIFT) | irq;
  71
  72     kvm_set_irq(kvm_state, kvm_irq, !!level);
  73 }
  74
  75 static void kvm_arm_gic_put(GICState *s)
  76 {
  77     /* TODO: there isn't currently a kernel interface to set the GIC state */
  78 }
  79
  80 static void kvm_arm_gic_get(GICState *s)
  81 {
  82     /* TODO: there isn't currently a kernel interface to get the GIC state */
  83 }
  84
  85 static void kvm_arm_gic_reset(DeviceState *dev)
  86 {
  87     GICState *s = ARM_GIC_COMMON(dev);
  88     KVMARMGICClass *kgc = KVM_ARM_GIC_GET_CLASS(s);
  89
  90     kgc->parent_reset(dev);
  91     kvm_arm_gic_put(s);
  92 }
  93
  94 static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
  95 {
  96     int i;
  97     GICState *s = KVM_ARM_GIC(dev);
  98     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
  99     KVMARMGICClass *kgc = KVM_ARM_GIC_GET_CLASS(s);
 100
 101     kgc->parent_realize(dev, errp);
 102     if (error_is_set(errp)) {
 103         return;
 104     }
 105
 106     i = s->num_irq - GIC_INTERNAL;
 107     /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
 108      * GPIO array layout is thus:
 109      *  [0..N-1] SPIs
 110      *  [N..N+31] PPIs for CPU 0
 111      *  [N+32..N+63] PPIs for CPU 1
 112      *   ...
 113      */
 114     i += (GIC_INTERNAL * s->num_cpu);
 115     qdev_init_gpio_in(dev, kvm_arm_gic_set_irq, i);
 116     /* We never use our outbound IRQ lines but provide them so that
 117      * we maintain the same interface as the non-KVM GIC.
 118      */
 119     for (i = 0; i < s->num_cpu; i++) {
 120         sysbus_init_irq(sbd, &s->parent_irq[i]);
 121     }
 122     /* Distributor */
 123     memory_region_init_reservation(&s->iomem, "kvm-gic_dist", 0x1000);
 124     sysbus_init_mmio(sbd, &s->iomem);
 125     kvm_arm_register_device(&s->iomem,
 126                             (KVM_ARM_DEVICE_VGIC_V2 << KVM_ARM_DEVICE_ID_SHIFT)
 127                             | KVM_VGIC_V2_ADDR_TYPE_DIST);
 128     /* CPU interface for current core. Unlike arm_gic, we don't
 129      * provide the "interface for core #N" memory regions, because
 130      * cores with a VGIC don't have those.
 131      */
 132     memory_region_init_reservation(&s->cpuiomem[0], "kvm-gic_cpu", 0x1000);
 133     sysbus_init_mmio(sbd, &s->cpuiomem[0]);
 134     kvm_arm_register_device(&s->cpuiomem[0],
 135                             (KVM_ARM_DEVICE_VGIC_V2 << KVM_ARM_DEVICE_ID_SHIFT)
 136                             | KVM_VGIC_V2_ADDR_TYPE_CPU);
 137 }
 138
 139 static void kvm_arm_gic_class_init(ObjectClass *klass, void *data)
 140 {
 141     DeviceClass *dc = DEVICE_CLASS(klass);
 142     ARMGICCommonClass *agcc = ARM_GIC_COMMON_CLASS(klass);
 143     KVMARMGICClass *kgc = KVM_ARM_GIC_CLASS(klass);
 144
 145     agcc->pre_save = kvm_arm_gic_get;
 146     agcc->post_load = kvm_arm_gic_put;
 147     kgc->parent_realize = dc->realize;
 148     kgc->parent_reset = dc->reset;
 149     dc->realize = kvm_arm_gic_realize;
 150     dc->reset = kvm_arm_gic_reset;
 151     dc->no_user = 1;
 152 }
 153
 154 static const TypeInfo kvm_arm_gic_info = {
 155     .name = TYPE_KVM_ARM_GIC,
 156     .parent = TYPE_ARM_GIC_COMMON,
 157     .instance_size = sizeof(GICState),
 158     .class_init = kvm_arm_gic_class_init,
 159     .class_size = sizeof(KVMARMGICClass),
 160 };
 161
 162 static void kvm_arm_gic_register_types(void)
 163 {
 164     type_register_static(&kvm_arm_gic_info);
 165 }
 166
 167 type_init(kvm_arm_gic_register_types)