xref: /openbmc/qemu/hw/intc/loongarch_ipi.c (revision 9b089d25)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * LoongArch ipi interrupt support
4  *
5  * Copyright (C) 2021 Loongson Technology Corporation Limited
6  */
7 
8 #include "qemu/osdep.h"
9 #include "hw/boards.h"
10 #include "hw/sysbus.h"
11 #include "hw/intc/loongarch_ipi.h"
12 #include "hw/irq.h"
13 #include "hw/qdev-properties.h"
14 #include "qapi/error.h"
15 #include "qemu/log.h"
16 #include "exec/address-spaces.h"
17 #include "migration/vmstate.h"
18 #include "target/loongarch/cpu.h"
19 #include "trace.h"
20 
21 static MemTxResult loongarch_ipi_readl(void *opaque, hwaddr addr,
22                                        uint64_t *data,
23                                        unsigned size, MemTxAttrs attrs)
24 {
25     IPICore *s;
26     LoongArchIPI *ipi = opaque;
27     uint64_t ret = 0;
28     int index = 0;
29 
30     s = &ipi->cpu[attrs.requester_id];
31     addr &= 0xff;
32     switch (addr) {
33     case CORE_STATUS_OFF:
34         ret = s->status;
35         break;
36     case CORE_EN_OFF:
37         ret = s->en;
38         break;
39     case CORE_SET_OFF:
40         ret = 0;
41         break;
42     case CORE_CLEAR_OFF:
43         ret = 0;
44         break;
45     case CORE_BUF_20 ... CORE_BUF_38 + 4:
46         index = (addr - CORE_BUF_20) >> 2;
47         ret = s->buf[index];
48         break;
49     default:
50         qemu_log_mask(LOG_UNIMP, "invalid read: %x", (uint32_t)addr);
51         break;
52     }
53 
54     trace_loongarch_ipi_read(size, (uint64_t)addr, ret);
55     *data = ret;
56     return MEMTX_OK;
57 }
58 
59 static void send_ipi_data(CPULoongArchState *env, uint64_t val, hwaddr addr,
60                           MemTxAttrs attrs)
61 {
62     int i, mask = 0, data = 0;
63 
64     /*
65      * bit 27-30 is mask for byte writing,
66      * if the mask is 0, we need not to do anything.
67      */
68     if ((val >> 27) & 0xf) {
69         data = address_space_ldl(env->address_space_iocsr, addr,
70                                  attrs, NULL);
71         for (i = 0; i < 4; i++) {
72             /* get mask for byte writing */
73             if (val & (0x1 << (27 + i))) {
74                 mask |= 0xff << (i * 8);
75             }
76         }
77     }
78 
79     data &= mask;
80     data |= (val >> 32) & ~mask;
81     address_space_stl(env->address_space_iocsr, addr,
82                       data, attrs, NULL);
83 }
84 
85 static int archid_cmp(const void *a, const void *b)
86 {
87    CPUArchId *archid_a = (CPUArchId *)a;
88    CPUArchId *archid_b = (CPUArchId *)b;
89 
90    return archid_a->arch_id - archid_b->arch_id;
91 }
92 
93 static CPUArchId *find_cpu_by_archid(MachineState *ms, uint32_t id)
94 {
95     CPUArchId apic_id, *found_cpu;
96 
97     apic_id.arch_id = id;
98     found_cpu = bsearch(&apic_id, ms->possible_cpus->cpus,
99         ms->possible_cpus->len, sizeof(*ms->possible_cpus->cpus),
100         archid_cmp);
101 
102     return found_cpu;
103 }
104 
105 static CPUState *ipi_getcpu(int arch_id)
106 {
107     MachineState *machine = MACHINE(qdev_get_machine());
108     CPUArchId *archid;
109 
110     archid = find_cpu_by_archid(machine, arch_id);
111     if (archid) {
112         return CPU(archid->cpu);
113     }
114 
115     return NULL;
116 }
117 
118 static MemTxResult mail_send(uint64_t val, MemTxAttrs attrs)
119 {
120     uint32_t cpuid;
121     hwaddr addr;
122     CPUState *cs;
123 
124     cpuid = extract32(val, 16, 10);
125     cs = ipi_getcpu(cpuid);
126     if (cs == NULL) {
127         return MEMTX_DECODE_ERROR;
128     }
129 
130     /* override requester_id */
131     addr = SMP_IPI_MAILBOX + CORE_BUF_20 + (val & 0x1c);
132     attrs.requester_id = cs->cpu_index;
133     send_ipi_data(&LOONGARCH_CPU(cs)->env, val, addr, attrs);
134     return MEMTX_OK;
135 }
136 
137 static MemTxResult any_send(uint64_t val, MemTxAttrs attrs)
138 {
139     uint32_t cpuid;
140     hwaddr addr;
141     CPUState *cs;
142 
143     cpuid = extract32(val, 16, 10);
144     cs = ipi_getcpu(cpuid);
145     if (cs == NULL) {
146         return MEMTX_DECODE_ERROR;
147     }
148 
149     /* override requester_id */
150     addr = val & 0xffff;
151     attrs.requester_id = cs->cpu_index;
152     send_ipi_data(&LOONGARCH_CPU(cs)->env, val, addr, attrs);
153     return MEMTX_OK;
154 }
155 
156 static MemTxResult loongarch_ipi_writel(void *opaque, hwaddr addr, uint64_t val,
157                                         unsigned size, MemTxAttrs attrs)
158 {
159     LoongArchIPI *ipi = opaque;
160     IPICore *s;
161     int index = 0;
162     uint32_t cpuid;
163     uint8_t vector;
164     CPUState *cs;
165 
166     s = &ipi->cpu[attrs.requester_id];
167     addr &= 0xff;
168     trace_loongarch_ipi_write(size, (uint64_t)addr, val);
169     switch (addr) {
170     case CORE_STATUS_OFF:
171         qemu_log_mask(LOG_GUEST_ERROR, "can not be written");
172         break;
173     case CORE_EN_OFF:
174         s->en = val;
175         break;
176     case CORE_SET_OFF:
177         s->status |= val;
178         if (s->status != 0 && (s->status & s->en) != 0) {
179             qemu_irq_raise(s->irq);
180         }
181         break;
182     case CORE_CLEAR_OFF:
183         s->status &= ~val;
184         if (s->status == 0 && s->en != 0) {
185             qemu_irq_lower(s->irq);
186         }
187         break;
188     case CORE_BUF_20 ... CORE_BUF_38 + 4:
189         index = (addr - CORE_BUF_20) >> 2;
190         s->buf[index] = val;
191         break;
192     case IOCSR_IPI_SEND:
193         cpuid = extract32(val, 16, 10);
194         /* IPI status vector */
195         vector = extract8(val, 0, 5);
196         cs = ipi_getcpu(cpuid);
197         if (cs == NULL) {
198             return MEMTX_DECODE_ERROR;
199         }
200 
201         /* override requester_id */
202         attrs.requester_id = cs->cpu_index;
203         loongarch_ipi_writel(ipi, CORE_SET_OFF, BIT(vector), 4, attrs);
204         break;
205     default:
206         qemu_log_mask(LOG_UNIMP, "invalid write: %x", (uint32_t)addr);
207         break;
208     }
209 
210     return MEMTX_OK;
211 }
212 
213 static const MemoryRegionOps loongarch_ipi_ops = {
214     .read_with_attrs = loongarch_ipi_readl,
215     .write_with_attrs = loongarch_ipi_writel,
216     .impl.min_access_size = 4,
217     .impl.max_access_size = 4,
218     .valid.min_access_size = 4,
219     .valid.max_access_size = 8,
220     .endianness = DEVICE_LITTLE_ENDIAN,
221 };
222 
223 /* mail send and any send only support writeq */
224 static MemTxResult loongarch_ipi_writeq(void *opaque, hwaddr addr, uint64_t val,
225                                         unsigned size, MemTxAttrs attrs)
226 {
227     MemTxResult ret = MEMTX_OK;
228 
229     addr &= 0xfff;
230     switch (addr) {
231     case MAIL_SEND_OFFSET:
232         ret = mail_send(val, attrs);
233         break;
234     case ANY_SEND_OFFSET:
235         ret = any_send(val, attrs);
236         break;
237     default:
238        break;
239     }
240 
241     return ret;
242 }
243 
244 static const MemoryRegionOps loongarch_ipi64_ops = {
245     .write_with_attrs = loongarch_ipi_writeq,
246     .impl.min_access_size = 8,
247     .impl.max_access_size = 8,
248     .valid.min_access_size = 8,
249     .valid.max_access_size = 8,
250     .endianness = DEVICE_LITTLE_ENDIAN,
251 };
252 
253 static void loongarch_ipi_realize(DeviceState *dev, Error **errp)
254 {
255     LoongArchIPI *s = LOONGARCH_IPI(dev);
256     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
257     int i;
258 
259     if (s->num_cpu == 0) {
260         error_setg(errp, "num-cpu must be at least 1");
261         return;
262     }
263 
264     memory_region_init_io(&s->ipi_iocsr_mem, OBJECT(dev), &loongarch_ipi_ops,
265                           s, "loongarch_ipi_iocsr", 0x48);
266 
267     /* loongarch_ipi_iocsr performs re-entrant IO through ipi_send */
268     s->ipi_iocsr_mem.disable_reentrancy_guard = true;
269 
270     sysbus_init_mmio(sbd, &s->ipi_iocsr_mem);
271 
272     memory_region_init_io(&s->ipi64_iocsr_mem, OBJECT(dev),
273                           &loongarch_ipi64_ops,
274                           s, "loongarch_ipi64_iocsr", 0x118);
275     sysbus_init_mmio(sbd, &s->ipi64_iocsr_mem);
276 
277     s->cpu = g_new0(IPICore, s->num_cpu);
278     if (s->cpu == NULL) {
279         error_setg(errp, "Memory allocation for ExtIOICore faile");
280         return;
281     }
282 
283     for (i = 0; i < s->num_cpu; i++) {
284         qdev_init_gpio_out(dev, &s->cpu[i].irq, 1);
285     }
286 }
287 
288 static const VMStateDescription vmstate_ipi_core = {
289     .name = "ipi-single",
290     .version_id = 2,
291     .minimum_version_id = 2,
292     .fields = (const VMStateField[]) {
293         VMSTATE_UINT32(status, IPICore),
294         VMSTATE_UINT32(en, IPICore),
295         VMSTATE_UINT32(set, IPICore),
296         VMSTATE_UINT32(clear, IPICore),
297         VMSTATE_UINT32_ARRAY(buf, IPICore, IPI_MBX_NUM * 2),
298         VMSTATE_END_OF_LIST()
299     }
300 };
301 
302 static const VMStateDescription vmstate_loongarch_ipi = {
303     .name = TYPE_LOONGARCH_IPI,
304     .version_id = 2,
305     .minimum_version_id = 2,
306     .fields = (const VMStateField[]) {
307         VMSTATE_STRUCT_VARRAY_POINTER_UINT32(cpu, LoongArchIPI, num_cpu,
308                          vmstate_ipi_core, IPICore),
309         VMSTATE_END_OF_LIST()
310     }
311 };
312 
313 static Property ipi_properties[] = {
314     DEFINE_PROP_UINT32("num-cpu", LoongArchIPI, num_cpu, 1),
315     DEFINE_PROP_END_OF_LIST(),
316 };
317 
318 static void loongarch_ipi_class_init(ObjectClass *klass, void *data)
319 {
320     DeviceClass *dc = DEVICE_CLASS(klass);
321 
322     dc->realize = loongarch_ipi_realize;
323     device_class_set_props(dc, ipi_properties);
324     dc->vmsd = &vmstate_loongarch_ipi;
325 }
326 
327 static void loongarch_ipi_finalize(Object *obj)
328 {
329     LoongArchIPI *s = LOONGARCH_IPI(obj);
330 
331     g_free(s->cpu);
332 }
333 
334 static const TypeInfo loongarch_ipi_info = {
335     .name          = TYPE_LOONGARCH_IPI,
336     .parent        = TYPE_SYS_BUS_DEVICE,
337     .instance_size = sizeof(LoongArchIPI),
338     .class_init    = loongarch_ipi_class_init,
339     .instance_finalize = loongarch_ipi_finalize,
340 };
341 
342 static void loongarch_ipi_register_types(void)
343 {
344     type_register_static(&loongarch_ipi_info);
345 }
346 
347 type_init(loongarch_ipi_register_types)
348