virt/kvm/ioapic.c

   1 /*
   2  *  Copyright (C) 2001  MandrakeSoft S.A.
   3  *
   4  *    MandrakeSoft S.A.
   5  *    43, rue d'Aboukir
   6  *    75002 Paris - France
   7  *    http://www.linux-mandrake.com/
   8  *    http://www.mandrakesoft.com/
   9  *
  10  *  This library is free software; you can redistribute it and/or
  11  *  modify it under the terms of the GNU Lesser General Public
  12  *  License as published by the Free Software Foundation; either
  13  *  version 2 of the License, or (at your option) any later version.
  14  *
  15  *  This library is distributed in the hope that it will be useful,
  16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  Lesser General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU Lesser General Public
  21  *  License along with this library; if not, write to the Free Software
  22  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  23  *
  24  *  Yunhong Jiang <yunhong.jiang@intel.com>
  25  *  Yaozu (Eddie) Dong <eddie.dong@intel.com>
  26  *  Based on Xen 3.1 code.
  27  */
  28
  29 #include <linux/kvm_host.h>
  30 #include <linux/kvm.h>
  31 #include <linux/mm.h>
  32 #include <linux/highmem.h>
  33 #include <linux/smp.h>
  34 #include <linux/hrtimer.h>
  35 #include <linux/io.h>
  36 #include <asm/processor.h>
  37 #include <asm/page.h>
  38 #include <asm/current.h>
  39
  40 #include "ioapic.h"
  41 #include "lapic.h"
  42 #include "irq.h"
  43
  44 #if 0
  45 #define ioapic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg)
  46 #else
  47 #define ioapic_debug(fmt, arg...)
  48 #endif
  49 static int ioapic_deliver(struct kvm_ioapic *vioapic, int irq);
  50
  51 static unsigned long ioapic_read_indirect(struct kvm_ioapic *ioapic,
  52                                           unsigned long addr,
  53                                           unsigned long length)
  54 {
  55         unsigned long result = 0;
  56
  57         switch (ioapic->ioregsel) {
  58         case IOAPIC_REG_VERSION:
  59                 result = ((((IOAPIC_NUM_PINS - 1) & 0xff) << 16)
  60                           | (IOAPIC_VERSION_ID & 0xff));
  61                 break;
  62
  63         case IOAPIC_REG_APIC_ID:
  64         case IOAPIC_REG_ARB_ID:
  65                 result = ((ioapic->id & 0xf) << 24);
  66                 break;
  67
  68         default:
  69                 {
  70                         u32 redir_index = (ioapic->ioregsel - 0x10) >> 1;
  71                         u64 redir_content;
  72
  73                         ASSERT(redir_index < IOAPIC_NUM_PINS);
  74
  75                         redir_content = ioapic->redirtbl[redir_index].bits;
  76                         result = (ioapic->ioregsel & 0x1) ?
  77                             (redir_content >> 32) & 0xffffffff :
  78                             redir_content & 0xffffffff;
  79                         break;
  80                 }
  81         }
  82
  83         return result;
  84 }
  85
  86 static int ioapic_service(struct kvm_ioapic *ioapic, unsigned int idx)
  87 {
  88         union kvm_ioapic_redirect_entry *pent;
  89         int injected = -1;
  90
  91         pent = &ioapic->redirtbl[idx];
  92
  93         if (!pent->fields.mask) {
  94                 injected = ioapic_deliver(ioapic, idx);
  95                 if (injected && pent->fields.trig_mode == IOAPIC_LEVEL_TRIG)
  96                         pent->fields.remote_irr = 1;
  97         }
  98         if (!pent->fields.trig_mode)
  99                 ioapic->irr &= ~(1 << idx);
 100
 101         return injected;
 102 }
 103
 104 static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
 105 {
 106         unsigned index;
 107         bool mask_before, mask_after;
 108
 109         switch (ioapic->ioregsel) {
 110         case IOAPIC_REG_VERSION:
 111                 /* Writes are ignored. */
 112                 break;
 113
 114         case IOAPIC_REG_APIC_ID:
 115                 ioapic->id = (val >> 24) & 0xf;
 116                 break;
 117
 118         case IOAPIC_REG_ARB_ID:
 119                 break;
 120
 121         default:
 122                 index = (ioapic->ioregsel - 0x10) >> 1;
 123
 124                 ioapic_debug("change redir index %x val %x\n", index, val);
 125                 if (index >= IOAPIC_NUM_PINS)
 126                         return;
 127                 mask_before = ioapic->redirtbl[index].fields.mask;
 128                 if (ioapic->ioregsel & 1) {
 129                         ioapic->redirtbl[index].bits &= 0xffffffff;
 130                         ioapic->redirtbl[index].bits |= (u64) val << 32;
 131                 } else {
 132                         ioapic->redirtbl[index].bits &= ~0xffffffffULL;
 133                         ioapic->redirtbl[index].bits |= (u32) val;
 134                         ioapic->redirtbl[index].fields.remote_irr = 0;
 135                 }
 136                 mask_after = ioapic->redirtbl[index].fields.mask;
 137                 if (mask_before != mask_after)
 138                         kvm_fire_mask_notifiers(ioapic->kvm, index, mask_after);
 139                 if (ioapic->irr & (1 << index))
 140                         ioapic_service(ioapic, index);
 141                 break;
 142         }
 143 }
 144
 145 int ioapic_deliver_entry(struct kvm *kvm, union kvm_ioapic_redirect_entry *e)
 146 {
 147         DECLARE_BITMAP(deliver_bitmask, KVM_MAX_VCPUS);
 148         int i, r = -1;
 149
 150         kvm_get_intr_delivery_bitmask(kvm, e, deliver_bitmask);
 151
 152         if (find_first_bit(deliver_bitmask, KVM_MAX_VCPUS) >= KVM_MAX_VCPUS) {
 153                 ioapic_debug("no target on destination\n");
 154                 return r;
 155         }
 156
 157         while ((i = find_first_bit(deliver_bitmask, KVM_MAX_VCPUS))
 158                         < KVM_MAX_VCPUS) {
 159                 struct kvm_vcpu *vcpu = kvm->vcpus[i];
 160                 __clear_bit(i, deliver_bitmask);
 161                 if (vcpu) {
 162                         if (r < 0)
 163                                 r = 0;
 164                         r += kvm_apic_set_irq(vcpu, e->fields.vector,
 165                                         e->fields.delivery_mode,
 166                                         e->fields.trig_mode);
 167                 } else
 168                         ioapic_debug("null destination vcpu: "
 169                                      "mask=%x vector=%x delivery_mode=%x\n",
 170                                      e->fields.deliver_bitmask,
 171                                      e->fields.vector, e->fields.delivery_mode);
 172         }
 173         return r;
 174 }
 175
 176 static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq)
 177 {
 178         union kvm_ioapic_redirect_entry entry = ioapic->redirtbl[irq];
 179
 180         ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
 181                      "vector=%x trig_mode=%x\n",
 182                      entry.fields.dest, entry.fields.dest_mode,
 183                      entry.fields.delivery_mode, entry.fields.vector,
 184                      entry.fields.trig_mode);
 185
 186 #ifdef CONFIG_X86
 187         /* Always delivery PIT interrupt to vcpu 0 */
 188         if (irq == 0) {
 189                 entry.fields.dest_mode = 0; /* Physical mode. */
 190                 entry.fields.dest_id = ioapic->kvm->vcpus[0]->vcpu_id;
 191         }
 192 #endif
 193         return ioapic_deliver_entry(ioapic->kvm, &entry);
 194 }
 195
 196 int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
 197 {
 198         u32 old_irr = ioapic->irr;
 199         u32 mask = 1 << irq;
 200         union kvm_ioapic_redirect_entry entry;
 201         int ret = 1;
 202
 203         if (irq >= 0 && irq < IOAPIC_NUM_PINS) {
 204                 entry = ioapic->redirtbl[irq];
 205                 level ^= entry.fields.polarity;
 206                 if (!level)
 207                         ioapic->irr &= ~mask;
 208                 else {
 209                         ioapic->irr |= mask;
 210                         if ((!entry.fields.trig_mode && old_irr != ioapic->irr)
 211                             || !entry.fields.remote_irr)
 212                                 ret = ioapic_service(ioapic, irq);
 213                 }
 214         }
 215         return ret;
 216 }
 217
 218 static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int pin,
 219                                     int trigger_mode)
 220 {
 221         union kvm_ioapic_redirect_entry *ent;
 222
 223         ent = &ioapic->redirtbl[pin];
 224
 225         kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, pin);
 226
 227         if (trigger_mode == IOAPIC_LEVEL_TRIG) {
 228                 ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
 229                 ent->fields.remote_irr = 0;
 230                 if (!ent->fields.mask && (ioapic->irr & (1 << pin)))
 231                         ioapic_service(ioapic, pin);
 232         }
 233 }
 234
 235 void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode)
 236 {
 237         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
 238         int i;
 239
 240         for (i = 0; i < IOAPIC_NUM_PINS; i++)
 241                 if (ioapic->redirtbl[i].fields.vector == vector)
 242                         __kvm_ioapic_update_eoi(ioapic, i, trigger_mode);
 243 }
 244
 245 static int ioapic_in_range(struct kvm_io_device *this, gpa_t addr,
 246                            int len, int is_write)
 247 {
 248         struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private;
 249
 250         return ((addr >= ioapic->base_address &&
 251                  (addr < ioapic->base_address + IOAPIC_MEM_LENGTH)));
 252 }
 253
 254 static void ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
 255                              void *val)
 256 {
 257         struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private;
 258         u32 result;
 259
 260         ioapic_debug("addr %lx\n", (unsigned long)addr);
 261         ASSERT(!(addr & 0xf));  /* check alignment */
 262
 263         addr &= 0xff;
 264         switch (addr) {
 265         case IOAPIC_REG_SELECT:
 266                 result = ioapic->ioregsel;
 267                 break;
 268
 269         case IOAPIC_REG_WINDOW:
 270                 result = ioapic_read_indirect(ioapic, addr, len);
 271                 break;
 272
 273         default:
 274                 result = 0;
 275                 break;
 276         }
 277         switch (len) {
 278         case 8:
 279                 *(u64 *) val = result;
 280                 break;
 281         case 1:
 282         case 2:
 283         case 4:
 284                 memcpy(val, (char *)&result, len);
 285                 break;
 286         default:
 287                 printk(KERN_WARNING "ioapic: wrong length %d\n", len);
 288         }
 289 }
 290
 291 static void ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
 292                               const void *val)
 293 {
 294         struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private;
 295         u32 data;
 296
 297         ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
 298                      (void*)addr, len, val);
 299         ASSERT(!(addr & 0xf));  /* check alignment */
 300         if (len == 4 || len == 8)
 301                 data = *(u32 *) val;
 302         else {
 303                 printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
 304                 return;
 305         }
 306
 307         addr &= 0xff;
 308         switch (addr) {
 309         case IOAPIC_REG_SELECT:
 310                 ioapic->ioregsel = data;
 311                 break;
 312
 313         case IOAPIC_REG_WINDOW:
 314                 ioapic_write_indirect(ioapic, data);
 315                 break;
 316 #ifdef  CONFIG_IA64
 317         case IOAPIC_REG_EOI:
 318                 kvm_ioapic_update_eoi(ioapic->kvm, data, IOAPIC_LEVEL_TRIG);
 319                 break;
 320 #endif
 321
 322         default:
 323                 break;
 324         }
 325 }
 326
 327 void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
 328 {
 329         int i;
 330
 331         for (i = 0; i < IOAPIC_NUM_PINS; i++)
 332                 ioapic->redirtbl[i].fields.mask = 1;
 333         ioapic->base_address = IOAPIC_DEFAULT_BASE_ADDRESS;
 334         ioapic->ioregsel = 0;
 335         ioapic->irr = 0;
 336         ioapic->id = 0;
 337 }
 338
 339 int kvm_ioapic_init(struct kvm *kvm)
 340 {
 341         struct kvm_ioapic *ioapic;
 342
 343         ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);
 344         if (!ioapic)
 345                 return -ENOMEM;
 346         kvm->arch.vioapic = ioapic;
 347         kvm_ioapic_reset(ioapic);
 348         ioapic->dev.read = ioapic_mmio_read;
 349         ioapic->dev.write = ioapic_mmio_write;
 350         ioapic->dev.in_range = ioapic_in_range;
 351         ioapic->dev.private = ioapic;
 352         ioapic->kvm = kvm;
 353         kvm_io_bus_register_dev(&kvm->mmio_bus, &ioapic->dev);
 354         return 0;
 355 }
 356