xref: /openbmc/qemu/hw/intc/ioapic.c (revision b2c623a3)
1 /*
2  *  ioapic.c IOAPIC emulation logic
3  *
4  *  Copyright (c) 2004-2005 Fabrice Bellard
5  *
6  *  Split the ioapic logic from apic.c
7  *  Xiantao Zhang <xiantao.zhang@intel.com>
8  *
9  * This library is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2 of the License, or (at your option) any later version.
13  *
14  * This library is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
21  */
22 
23 #include "hw/hw.h"
24 #include "hw/i386/pc.h"
25 #include "hw/i386/ioapic.h"
26 #include "hw/i386/ioapic_internal.h"
27 
28 //#define DEBUG_IOAPIC
29 
30 #ifdef DEBUG_IOAPIC
31 #define DPRINTF(fmt, ...)                                       \
32     do { printf("ioapic: " fmt , ## __VA_ARGS__); } while (0)
33 #else
34 #define DPRINTF(fmt, ...)
35 #endif
36 
37 static IOAPICCommonState *ioapics[MAX_IOAPICS];
38 
39 /* global variable from ioapic_common.c */
40 extern int ioapic_no;
41 
42 static void ioapic_service(IOAPICCommonState *s)
43 {
44     uint8_t i;
45     uint8_t trig_mode;
46     uint8_t vector;
47     uint8_t delivery_mode;
48     uint32_t mask;
49     uint64_t entry;
50     uint8_t dest;
51     uint8_t dest_mode;
52 
53     for (i = 0; i < IOAPIC_NUM_PINS; i++) {
54         mask = 1 << i;
55         if (s->irr & mask) {
56             entry = s->ioredtbl[i];
57             if (!(entry & IOAPIC_LVT_MASKED)) {
58                 trig_mode = ((entry >> IOAPIC_LVT_TRIGGER_MODE_SHIFT) & 1);
59                 dest = entry >> IOAPIC_LVT_DEST_SHIFT;
60                 dest_mode = (entry >> IOAPIC_LVT_DEST_MODE_SHIFT) & 1;
61                 delivery_mode =
62                     (entry >> IOAPIC_LVT_DELIV_MODE_SHIFT) & IOAPIC_DM_MASK;
63                 if (trig_mode == IOAPIC_TRIGGER_EDGE) {
64                     s->irr &= ~mask;
65                 } else {
66                     s->ioredtbl[i] |= IOAPIC_LVT_REMOTE_IRR;
67                 }
68                 if (delivery_mode == IOAPIC_DM_EXTINT) {
69                     vector = pic_read_irq(isa_pic);
70                 } else {
71                     vector = entry & IOAPIC_VECTOR_MASK;
72                 }
73                 apic_deliver_irq(dest, dest_mode, delivery_mode,
74                                  vector, trig_mode);
75             }
76         }
77     }
78 }
79 
80 static void ioapic_set_irq(void *opaque, int vector, int level)
81 {
82     IOAPICCommonState *s = opaque;
83 
84     /* ISA IRQs map to GSI 1-1 except for IRQ0 which maps
85      * to GSI 2.  GSI maps to ioapic 1-1.  This is not
86      * the cleanest way of doing it but it should work. */
87 
88     DPRINTF("%s: %s vec %x\n", __func__, level ? "raise" : "lower", vector);
89     if (vector == 0) {
90         vector = 2;
91     }
92     if (vector >= 0 && vector < IOAPIC_NUM_PINS) {
93         uint32_t mask = 1 << vector;
94         uint64_t entry = s->ioredtbl[vector];
95 
96         if (entry & (1 << IOAPIC_LVT_POLARITY_SHIFT)) {
97             level = !level;
98         }
99         if (((entry >> IOAPIC_LVT_TRIGGER_MODE_SHIFT) & 1) ==
100             IOAPIC_TRIGGER_LEVEL) {
101             /* level triggered */
102             if (level) {
103                 s->irr |= mask;
104                 ioapic_service(s);
105             } else {
106                 s->irr &= ~mask;
107             }
108         } else {
109             /* According to the 82093AA manual, we must ignore edge requests
110              * if the input pin is masked. */
111             if (level && !(entry & IOAPIC_LVT_MASKED)) {
112                 s->irr |= mask;
113                 ioapic_service(s);
114             }
115         }
116     }
117 }
118 
119 void ioapic_eoi_broadcast(int vector)
120 {
121     IOAPICCommonState *s;
122     uint64_t entry;
123     int i, n;
124 
125     for (i = 0; i < MAX_IOAPICS; i++) {
126         s = ioapics[i];
127         if (!s) {
128             continue;
129         }
130         for (n = 0; n < IOAPIC_NUM_PINS; n++) {
131             entry = s->ioredtbl[n];
132             if ((entry & IOAPIC_LVT_REMOTE_IRR)
133                 && (entry & IOAPIC_VECTOR_MASK) == vector) {
134                 s->ioredtbl[n] = entry & ~IOAPIC_LVT_REMOTE_IRR;
135                 if (!(entry & IOAPIC_LVT_MASKED) && (s->irr & (1 << n))) {
136                     ioapic_service(s);
137                 }
138             }
139         }
140     }
141 }
142 
143 static uint64_t
144 ioapic_mem_read(void *opaque, hwaddr addr, unsigned int size)
145 {
146     IOAPICCommonState *s = opaque;
147     int index;
148     uint32_t val = 0;
149 
150     switch (addr & 0xff) {
151     case IOAPIC_IOREGSEL:
152         val = s->ioregsel;
153         break;
154     case IOAPIC_IOWIN:
155         if (size != 4) {
156             break;
157         }
158         switch (s->ioregsel) {
159         case IOAPIC_REG_ID:
160             val = s->id << IOAPIC_ID_SHIFT;
161             break;
162         case IOAPIC_REG_VER:
163             val = IOAPIC_VERSION |
164                 ((IOAPIC_NUM_PINS - 1) << IOAPIC_VER_ENTRIES_SHIFT);
165             break;
166         case IOAPIC_REG_ARB:
167             val = 0;
168             break;
169         default:
170             index = (s->ioregsel - IOAPIC_REG_REDTBL_BASE) >> 1;
171             if (index >= 0 && index < IOAPIC_NUM_PINS) {
172                 if (s->ioregsel & 1) {
173                     val = s->ioredtbl[index] >> 32;
174                 } else {
175                     val = s->ioredtbl[index] & 0xffffffff;
176                 }
177             }
178         }
179         DPRINTF("read: %08x = %08x\n", s->ioregsel, val);
180         break;
181     }
182     return val;
183 }
184 
185 static void
186 ioapic_mem_write(void *opaque, hwaddr addr, uint64_t val,
187                  unsigned int size)
188 {
189     IOAPICCommonState *s = opaque;
190     int index;
191 
192     switch (addr & 0xff) {
193     case IOAPIC_IOREGSEL:
194         s->ioregsel = val;
195         break;
196     case IOAPIC_IOWIN:
197         if (size != 4) {
198             break;
199         }
200         DPRINTF("write: %08x = %08" PRIx64 "\n", s->ioregsel, val);
201         switch (s->ioregsel) {
202         case IOAPIC_REG_ID:
203             s->id = (val >> IOAPIC_ID_SHIFT) & IOAPIC_ID_MASK;
204             break;
205         case IOAPIC_REG_VER:
206         case IOAPIC_REG_ARB:
207             break;
208         default:
209             index = (s->ioregsel - IOAPIC_REG_REDTBL_BASE) >> 1;
210             if (index >= 0 && index < IOAPIC_NUM_PINS) {
211                 if (s->ioregsel & 1) {
212                     s->ioredtbl[index] &= 0xffffffff;
213                     s->ioredtbl[index] |= (uint64_t)val << 32;
214                 } else {
215                     s->ioredtbl[index] &= ~0xffffffffULL;
216                     s->ioredtbl[index] |= val;
217                 }
218                 ioapic_service(s);
219             }
220         }
221         break;
222     }
223 }
224 
225 static const MemoryRegionOps ioapic_io_ops = {
226     .read = ioapic_mem_read,
227     .write = ioapic_mem_write,
228     .endianness = DEVICE_NATIVE_ENDIAN,
229 };
230 
231 static void ioapic_realize(DeviceState *dev, Error **errp)
232 {
233     IOAPICCommonState *s = IOAPIC_COMMON(dev);
234 
235     memory_region_init_io(&s->io_memory, OBJECT(s), &ioapic_io_ops, s,
236                           "ioapic", 0x1000);
237 
238     qdev_init_gpio_in(dev, ioapic_set_irq, IOAPIC_NUM_PINS);
239 
240     ioapics[ioapic_no] = s;
241 }
242 
243 static void ioapic_class_init(ObjectClass *klass, void *data)
244 {
245     IOAPICCommonClass *k = IOAPIC_COMMON_CLASS(klass);
246     DeviceClass *dc = DEVICE_CLASS(klass);
247 
248     k->realize = ioapic_realize;
249     dc->reset = ioapic_reset_common;
250 }
251 
252 static const TypeInfo ioapic_info = {
253     .name          = "ioapic",
254     .parent        = TYPE_IOAPIC_COMMON,
255     .instance_size = sizeof(IOAPICCommonState),
256     .class_init    = ioapic_class_init,
257 };
258 
259 static void ioapic_register_types(void)
260 {
261     type_register_static(&ioapic_info);
262 }
263 
264 type_init(ioapic_register_types)
265