xref: /openbmc/qemu/hw/intc/ioapic.c (revision 56c4bfb3)
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 static void ioapic_service(IOAPICCommonState *s)
40 {
41     uint8_t i;
42     uint8_t trig_mode;
43     uint8_t vector;
44     uint8_t delivery_mode;
45     uint32_t mask;
46     uint64_t entry;
47     uint8_t dest;
48     uint8_t dest_mode;
49 
50     for (i = 0; i < IOAPIC_NUM_PINS; i++) {
51         mask = 1 << i;
52         if (s->irr & mask) {
53             entry = s->ioredtbl[i];
54             if (!(entry & IOAPIC_LVT_MASKED)) {
55                 trig_mode = ((entry >> IOAPIC_LVT_TRIGGER_MODE_SHIFT) & 1);
56                 dest = entry >> IOAPIC_LVT_DEST_SHIFT;
57                 dest_mode = (entry >> IOAPIC_LVT_DEST_MODE_SHIFT) & 1;
58                 delivery_mode =
59                     (entry >> IOAPIC_LVT_DELIV_MODE_SHIFT) & IOAPIC_DM_MASK;
60                 if (trig_mode == IOAPIC_TRIGGER_EDGE) {
61                     s->irr &= ~mask;
62                 } else {
63                     s->ioredtbl[i] |= IOAPIC_LVT_REMOTE_IRR;
64                 }
65                 if (delivery_mode == IOAPIC_DM_EXTINT) {
66                     vector = pic_read_irq(isa_pic);
67                 } else {
68                     vector = entry & IOAPIC_VECTOR_MASK;
69                 }
70                 apic_deliver_irq(dest, dest_mode, delivery_mode,
71                                  vector, trig_mode);
72             }
73         }
74     }
75 }
76 
77 static void ioapic_set_irq(void *opaque, int vector, int level)
78 {
79     IOAPICCommonState *s = opaque;
80 
81     /* ISA IRQs map to GSI 1-1 except for IRQ0 which maps
82      * to GSI 2.  GSI maps to ioapic 1-1.  This is not
83      * the cleanest way of doing it but it should work. */
84 
85     DPRINTF("%s: %s vec %x\n", __func__, level ? "raise" : "lower", vector);
86     if (vector == 0) {
87         vector = 2;
88     }
89     if (vector >= 0 && vector < IOAPIC_NUM_PINS) {
90         uint32_t mask = 1 << vector;
91         uint64_t entry = s->ioredtbl[vector];
92 
93         if (entry & (1 << IOAPIC_LVT_POLARITY_SHIFT)) {
94             level = !level;
95         }
96         if (((entry >> IOAPIC_LVT_TRIGGER_MODE_SHIFT) & 1) ==
97             IOAPIC_TRIGGER_LEVEL) {
98             /* level triggered */
99             if (level) {
100                 s->irr |= mask;
101                 ioapic_service(s);
102             } else {
103                 s->irr &= ~mask;
104             }
105         } else {
106             /* According to the 82093AA manual, we must ignore edge requests
107              * if the input pin is masked. */
108             if (level && !(entry & IOAPIC_LVT_MASKED)) {
109                 s->irr |= mask;
110                 ioapic_service(s);
111             }
112         }
113     }
114 }
115 
116 void ioapic_eoi_broadcast(int vector)
117 {
118     IOAPICCommonState *s;
119     uint64_t entry;
120     int i, n;
121 
122     for (i = 0; i < MAX_IOAPICS; i++) {
123         s = ioapics[i];
124         if (!s) {
125             continue;
126         }
127         for (n = 0; n < IOAPIC_NUM_PINS; n++) {
128             entry = s->ioredtbl[n];
129             if ((entry & IOAPIC_LVT_REMOTE_IRR)
130                 && (entry & IOAPIC_VECTOR_MASK) == vector) {
131                 s->ioredtbl[n] = entry & ~IOAPIC_LVT_REMOTE_IRR;
132                 if (!(entry & IOAPIC_LVT_MASKED) && (s->irr & (1 << n))) {
133                     ioapic_service(s);
134                 }
135             }
136         }
137     }
138 }
139 
140 static uint64_t
141 ioapic_mem_read(void *opaque, hwaddr addr, unsigned int size)
142 {
143     IOAPICCommonState *s = opaque;
144     int index;
145     uint32_t val = 0;
146 
147     switch (addr & 0xff) {
148     case IOAPIC_IOREGSEL:
149         val = s->ioregsel;
150         break;
151     case IOAPIC_IOWIN:
152         if (size != 4) {
153             break;
154         }
155         switch (s->ioregsel) {
156         case IOAPIC_REG_ID:
157             val = s->id << IOAPIC_ID_SHIFT;
158             break;
159         case IOAPIC_REG_VER:
160             val = IOAPIC_VERSION |
161                 ((IOAPIC_NUM_PINS - 1) << IOAPIC_VER_ENTRIES_SHIFT);
162             break;
163         case IOAPIC_REG_ARB:
164             val = 0;
165             break;
166         default:
167             index = (s->ioregsel - IOAPIC_REG_REDTBL_BASE) >> 1;
168             if (index >= 0 && index < IOAPIC_NUM_PINS) {
169                 if (s->ioregsel & 1) {
170                     val = s->ioredtbl[index] >> 32;
171                 } else {
172                     val = s->ioredtbl[index] & 0xffffffff;
173                 }
174             }
175         }
176         DPRINTF("read: %08x = %08x\n", s->ioregsel, val);
177         break;
178     }
179     return val;
180 }
181 
182 static void
183 ioapic_mem_write(void *opaque, hwaddr addr, uint64_t val,
184                  unsigned int size)
185 {
186     IOAPICCommonState *s = opaque;
187     int index;
188 
189     switch (addr & 0xff) {
190     case IOAPIC_IOREGSEL:
191         s->ioregsel = val;
192         break;
193     case IOAPIC_IOWIN:
194         if (size != 4) {
195             break;
196         }
197         DPRINTF("write: %08x = %08" PRIx64 "\n", s->ioregsel, val);
198         switch (s->ioregsel) {
199         case IOAPIC_REG_ID:
200             s->id = (val >> IOAPIC_ID_SHIFT) & IOAPIC_ID_MASK;
201             break;
202         case IOAPIC_REG_VER:
203         case IOAPIC_REG_ARB:
204             break;
205         default:
206             index = (s->ioregsel - IOAPIC_REG_REDTBL_BASE) >> 1;
207             if (index >= 0 && index < IOAPIC_NUM_PINS) {
208                 if (s->ioregsel & 1) {
209                     s->ioredtbl[index] &= 0xffffffff;
210                     s->ioredtbl[index] |= (uint64_t)val << 32;
211                 } else {
212                     s->ioredtbl[index] &= ~0xffffffffULL;
213                     s->ioredtbl[index] |= val;
214                 }
215                 ioapic_service(s);
216             }
217         }
218         break;
219     }
220 }
221 
222 static const MemoryRegionOps ioapic_io_ops = {
223     .read = ioapic_mem_read,
224     .write = ioapic_mem_write,
225     .endianness = DEVICE_NATIVE_ENDIAN,
226 };
227 
228 static void ioapic_init(IOAPICCommonState *s, int instance_no)
229 {
230     memory_region_init_io(&s->io_memory, OBJECT(s), &ioapic_io_ops, s,
231                           "ioapic", 0x1000);
232 
233     qdev_init_gpio_in(DEVICE(s), ioapic_set_irq, IOAPIC_NUM_PINS);
234 
235     ioapics[instance_no] = s;
236 }
237 
238 static void ioapic_class_init(ObjectClass *klass, void *data)
239 {
240     IOAPICCommonClass *k = IOAPIC_COMMON_CLASS(klass);
241     DeviceClass *dc = DEVICE_CLASS(klass);
242 
243     k->init = ioapic_init;
244     dc->reset = ioapic_reset_common;
245 }
246 
247 static const TypeInfo ioapic_info = {
248     .name          = "ioapic",
249     .parent        = TYPE_IOAPIC_COMMON,
250     .instance_size = sizeof(IOAPICCommonState),
251     .class_init    = ioapic_class_init,
252 };
253 
254 static void ioapic_register_types(void)
255 {
256     type_register_static(&ioapic_info);
257 }
258 
259 type_init(ioapic_register_types)
260