aboutsummaryrefslogtreecommitdiff
path: root/hw/intc/ioapic.c
blob: b6896ac4ce262049e4db3e98b50fd9ea75efd44c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
/*
 *  ioapic.c IOAPIC emulation logic
 *
 *  Copyright (c) 2004-2005 Fabrice Bellard
 *
 *  Split the ioapic logic from apic.c
 *  Xiantao Zhang <xiantao.zhang@intel.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */

#include "qemu/osdep.h"
#include "qemu/error-report.h"
#include "monitor/monitor.h"
#include "hw/hw.h"
#include "hw/i386/pc.h"
#include "hw/i386/apic.h"
#include "hw/i386/ioapic.h"
#include "hw/i386/ioapic_internal.h"
#include "hw/pci/msi.h"
#include "sysemu/kvm.h"
#include "hw/i386/apic-msidef.h"
#include "hw/i386/x86-iommu.h"
#include "trace.h"

#define APIC_DELIVERY_MODE_SHIFT 8
#define APIC_POLARITY_SHIFT 14
#define APIC_TRIG_MODE_SHIFT 15

static IOAPICCommonState *ioapics[MAX_IOAPICS];

/* global variable from ioapic_common.c */
extern int ioapic_no;

struct ioapic_entry_info {
    /* fields parsed from IOAPIC entries */
    uint8_t masked;
    uint8_t trig_mode;
    uint16_t dest_idx;
    uint8_t dest_mode;
    uint8_t delivery_mode;
    uint8_t vector;

    /* MSI message generated from above parsed fields */
    uint32_t addr;
    uint32_t data;
};

static void ioapic_entry_parse(uint64_t entry, struct ioapic_entry_info *info)
{
    memset(info, 0, sizeof(*info));
    info->masked = (entry >> IOAPIC_LVT_MASKED_SHIFT) & 1;
    info->trig_mode = (entry >> IOAPIC_LVT_TRIGGER_MODE_SHIFT) & 1;
    /*
     * By default, this would be dest_id[8] + reserved[8]. When IR
     * is enabled, this would be interrupt_index[15] +
     * interrupt_format[1]. This field never means anything, but
     * only used to generate corresponding MSI.
     */
    info->dest_idx = (entry >> IOAPIC_LVT_DEST_IDX_SHIFT) & 0xffff;
    info->dest_mode = (entry >> IOAPIC_LVT_DEST_MODE_SHIFT) & 1;
    info->delivery_mode = (entry >> IOAPIC_LVT_DELIV_MODE_SHIFT) \
        & IOAPIC_DM_MASK;
    if (info->delivery_mode == IOAPIC_DM_EXTINT) {
        info->vector = pic_read_irq(isa_pic);
    } else {
        info->vector = entry & IOAPIC_VECTOR_MASK;
    }

    info->addr = APIC_DEFAULT_ADDRESS | \
        (info->dest_idx << MSI_ADDR_DEST_IDX_SHIFT) | \
        (info->dest_mode << MSI_ADDR_DEST_MODE_SHIFT);
    info->data = (info->vector << MSI_DATA_VECTOR_SHIFT) | \
        (info->trig_mode << MSI_DATA_TRIGGER_SHIFT) | \
        (info->delivery_mode << MSI_DATA_DELIVERY_MODE_SHIFT);
}

static void ioapic_service(IOAPICCommonState *s)
{
    AddressSpace *ioapic_as = PC_MACHINE(qdev_get_machine())->ioapic_as;
    struct ioapic_entry_info info;
    uint8_t i;
    uint32_t mask;
    uint64_t entry;

    for (i = 0; i < IOAPIC_NUM_PINS; i++) {
        mask = 1 << i;
        if (s->irr & mask) {
            int coalesce = 0;

            entry = s->ioredtbl[i];
            ioapic_entry_parse(entry, &info);
            if (!info.masked) {
                if (info.trig_mode == IOAPIC_TRIGGER_EDGE) {
                    s->irr &= ~mask;
                } else {
                    coalesce = s->ioredtbl[i] & IOAPIC_LVT_REMOTE_IRR;
                    trace_ioapic_set_remote_irr(i);
                    s->ioredtbl[i] |= IOAPIC_LVT_REMOTE_IRR;
                }

                if (coalesce) {
                    /* We are level triggered interrupts, and the
                     * guest should be still working on previous one,
                     * so skip it. */
                    continue;
                }

#ifdef CONFIG_KVM
                if (kvm_irqchip_is_split()) {
                    if (info.trig_mode == IOAPIC_TRIGGER_EDGE) {
                        kvm_set_irq(kvm_state, i, 1);
                        kvm_set_irq(kvm_state, i, 0);
                    } else {
                        kvm_set_irq(kvm_state, i, 1);
                    }
                    continue;
                }
#endif

                /* No matter whether IR is enabled, we translate
                 * the IOAPIC message into a MSI one, and its
                 * address space will decide whether we need a
                 * translation. */
                stl_le_phys(ioapic_as, info.addr, info.data);
            }
        }
    }
}

static void ioapic_set_irq(void *opaque, int vector, int level)
{
    IOAPICCommonState *s = opaque;

    /* ISA IRQs map to GSI 1-1 except for IRQ0 which maps
     * to GSI 2.  GSI maps to ioapic 1-1.  This is not
     * the cleanest way of doing it but it should work. */

    trace_ioapic_set_irq(vector, level);
    ioapic_stat_update_irq(s, vector, level);
    if (vector == 0) {
        vector = 2;
    }
    if (vector < IOAPIC_NUM_PINS) {
        uint32_t mask = 1 << vector;
        uint64_t entry = s->ioredtbl[vector];

        if (((entry >> IOAPIC_LVT_TRIGGER_MODE_SHIFT) & 1) ==
            IOAPIC_TRIGGER_LEVEL) {
            /* level triggered */
            if (level) {
                s->irr |= mask;
                if (!(entry & IOAPIC_LVT_REMOTE_IRR)) {
                    ioapic_service(s);
                }
            } else {
                s->irr &= ~mask;
            }
        } else {
            /* According to the 82093AA manual, we must ignore edge requests
             * if the input pin is masked. */
            if (level && !(entry & IOAPIC_LVT_MASKED)) {
                s->irr |= mask;
                ioapic_service(s);
            }
        }
    }
}

static void ioapic_update_kvm_routes(IOAPICCommonState *s)
{
#ifdef CONFIG_KVM
    int i;

    if (kvm_irqchip_is_split()) {
        for (i = 0; i < IOAPIC_NUM_PINS; i++) {
            MSIMessage msg;
            struct ioapic_entry_info info;
            ioapic_entry_parse(s->ioredtbl[i], &info);
            msg.address = info.addr;
            msg.data = info.data;
            kvm_irqchip_update_msi_route(kvm_state, i, msg, NULL);
        }
        kvm_irqchip_commit_routes(kvm_state);
    }
#endif
}

#ifdef CONFIG_KVM
static void ioapic_iec_notifier(void *private, bool global,
                                uint32_t index, uint32_t mask)
{
    IOAPICCommonState *s = (IOAPICCommonState *)private;
    /* For simplicity, we just update all the routes */
    ioapic_update_kvm_routes(s);
}
#endif

void ioapic_eoi_broadcast(int vector)
{
    IOAPICCommonState *s;
    uint64_t entry;
    int i, n;

    trace_ioapic_eoi_broadcast(vector);

    for (i = 0; i < MAX_IOAPICS; i++) {
        s = ioapics[i];
        if (!s) {
            continue;
        }
        for (n = 0; n < IOAPIC_NUM_PINS; n++) {
            entry = s->ioredtbl[n];
            if ((entry & IOAPIC_LVT_REMOTE_IRR)
                && (entry & IOAPIC_VECTOR_MASK) == vector) {
                trace_ioapic_clear_remote_irr(n, vector);
                s->ioredtbl[n] = entry & ~IOAPIC_LVT_REMOTE_IRR;
                if (!(entry & IOAPIC_LVT_MASKED) && (s->irr & (1 << n))) {
                    ioapic_service(s);
                }
            }
        }
    }
}

static uint64_t
ioapic_mem_read(void *opaque, hwaddr addr, unsigned int size)
{
    IOAPICCommonState *s = opaque;
    int index;
    uint32_t val = 0;

    addr &= 0xff;

    switch (addr) {
    case IOAPIC_IOREGSEL:
        val = s->ioregsel;
        break;
    case IOAPIC_IOWIN:
        if (size != 4) {
            break;
        }
        switch (s->ioregsel) {
        case IOAPIC_REG_ID:
        case IOAPIC_REG_ARB:
            val = s->id << IOAPIC_ID_SHIFT;
            break;
        case IOAPIC_REG_VER:
            val = s->version |
                ((IOAPIC_NUM_PINS - 1) << IOAPIC_VER_ENTRIES_SHIFT);
            break;
        default:
            index = (s->ioregsel - IOAPIC_REG_REDTBL_BASE) >> 1;
            if (index >= 0 && index < IOAPIC_NUM_PINS) {
                if (s->ioregsel & 1) {
                    val = s->ioredtbl[index] >> 32;
                } else {
                    val = s->ioredtbl[index] & 0xffffffff;
                }
            }
        }
        break;
    }

    trace_ioapic_mem_read(addr, s->ioregsel, size, val);

    return val;
}

/*
 * This is to satisfy the hack in Linux kernel. One hack of it is to
 * simulate clearing the Remote IRR bit of IOAPIC entry using the
 * following:
 *
 * "For IO-APIC's with EOI register, we use that to do an explicit EOI.
 * Otherwise, we simulate the EOI message manually by changing the trigger
 * mode to edge and then back to level, with RTE being masked during
 * this."
 *
 * (See linux kernel __eoi_ioapic_pin() comment in commit c0205701)
 *
 * This is based on the assumption that, Remote IRR bit will be
 * cleared by IOAPIC hardware when configured as edge-triggered
 * interrupts.
 *
 * Without this, level-triggered interrupts in IR mode might fail to
 * work correctly.
 */
static inline void
ioapic_fix_edge_remote_irr(uint64_t *entry)
{
    if (!(*entry & IOAPIC_LVT_TRIGGER_MODE)) {
        /* Edge-triggered interrupts, make sure remote IRR is zero */
        *entry &= ~((uint64_t)IOAPIC_LVT_REMOTE_IRR);
    }
}

static void
ioapic_mem_write(void *opaque, hwaddr addr, uint64_t val,
                 unsigned int size)
{
    IOAPICCommonState *s = opaque;
    int index;

    addr &= 0xff;
    trace_ioapic_mem_write(addr, s->ioregsel, size, val);

    switch (addr) {
    case IOAPIC_IOREGSEL:
        s->ioregsel = val;
        break;
    case IOAPIC_IOWIN:
        if (size != 4) {
            break;
        }
        switch (s->ioregsel) {
        case IOAPIC_REG_ID:
            s->id = (val >> IOAPIC_ID_SHIFT) & IOAPIC_ID_MASK;
            break;
        case IOAPIC_REG_VER:
        case IOAPIC_REG_ARB:
            break;
        default:
            index = (s->ioregsel - IOAPIC_REG_REDTBL_BASE) >> 1;
            if (index >= 0 && index < IOAPIC_NUM_PINS) {
                uint64_t ro_bits = s->ioredtbl[index] & IOAPIC_RO_BITS;
                if (s->ioregsel & 1) {
                    s->ioredtbl[index] &= 0xffffffff;
                    s->ioredtbl[index] |= (uint64_t)val << 32;
                } else {
                    s->ioredtbl[index] &= ~0xffffffffULL;
                    s->ioredtbl[index] |= val;
                }
                /* restore RO bits */
                s->ioredtbl[index] &= IOAPIC_RW_BITS;
                s->ioredtbl[index] |= ro_bits;
                ioapic_fix_edge_remote_irr(&s->ioredtbl[index]);
                ioapic_service(s);
            }
        }
        break;
    case IOAPIC_EOI:
        /* Explicit EOI is only supported for IOAPIC version 0x20 */
        if (size != 4 || s->version != 0x20) {
            break;
        }
        ioapic_eoi_broadcast(val);
        break;
    }

    ioapic_update_kvm_routes(s);
}

static const MemoryRegionOps ioapic_io_ops = {
    .read = ioapic_mem_read,
    .write = ioapic_mem_write,
    .endianness = DEVICE_NATIVE_ENDIAN,
};

static void ioapic_machine_done_notify(Notifier *notifier, void *data)
{
#ifdef CONFIG_KVM
    IOAPICCommonState *s = container_of(notifier, IOAPICCommonState,
                                        machine_done);

    if (kvm_irqchip_is_split()) {
        X86IOMMUState *iommu = x86_iommu_get_default();
        if (iommu) {
            /* Register this IOAPIC with IOMMU IEC notifier, so that
             * when there are IR invalidates, we can be notified to
             * update kernel IR cache. */
            x86_iommu_iec_register_notifier(iommu, ioapic_iec_notifier, s);
        }
    }
#endif
}

#define IOAPIC_VER_DEF 0x20

static void ioapic_realize(DeviceState *dev, Error **errp)
{
    IOAPICCommonState *s = IOAPIC_COMMON(dev);

    if (s->version != 0x11 && s->version != 0x20) {
        error_report("IOAPIC only supports version 0x11 or 0x20 "
                     "(default: 0x%x).", IOAPIC_VER_DEF);
        exit(1);
    }

    memory_region_init_io(&s->io_memory, OBJECT(s), &ioapic_io_ops, s,
                          "ioapic", 0x1000);

    qdev_init_gpio_in(dev, ioapic_set_irq, IOAPIC_NUM_PINS);

    ioapics[ioapic_no] = s;
    s->machine_done.notify = ioapic_machine_done_notify;
    qemu_add_machine_init_done_notifier(&s->machine_done);
}

static Property ioapic_properties[] = {
    DEFINE_PROP_UINT8("version", IOAPICCommonState, version, IOAPIC_VER_DEF),
    DEFINE_PROP_END_OF_LIST(),
};

static void ioapic_class_init(ObjectClass *klass, void *data)
{
    IOAPICCommonClass *k = IOAPIC_COMMON_CLASS(klass);
    DeviceClass *dc = DEVICE_CLASS(klass);

    k->realize = ioapic_realize;
    /*
     * If APIC is in kernel, we need to update the kernel cache after
     * migration, otherwise first 24 gsi routes will be invalid.
     */
    k->post_load = ioapic_update_kvm_routes;
    dc->reset = ioapic_reset_common;
    dc->props = ioapic_properties;
}

static const TypeInfo ioapic_info = {
    .name          = "ioapic",
    .parent        = TYPE_IOAPIC_COMMON,
    .instance_size = sizeof(IOAPICCommonState),
    .class_init    = ioapic_class_init,
};

static void ioapic_register_types(void)
{
    type_register_static(&ioapic_info);
}

type_init(ioapic_register_types)