xref: /openbmc/qemu/hw/intc/loongarch_ipi.c (revision 6b504a01)
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/sysbus.h"
10 #include "hw/intc/loongarch_ipi.h"
11 #include "hw/irq.h"
12 #include "hw/qdev-properties.h"
13 #include "qapi/error.h"
14 #include "qemu/log.h"
15 #include "exec/address-spaces.h"
16 #include "hw/loongarch/virt.h"
17 #include "migration/vmstate.h"
18 #include "target/loongarch/internals.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     if (cpuid >= LOONGARCH_MAX_CPUS) {
126         trace_loongarch_ipi_unsupported_cpuid("IOCSR_MAIL_SEND", cpuid);
127         return MEMTX_DECODE_ERROR;
128     }
129 
130     cs = ipi_getcpu(cpuid);
131     if (cs == NULL) {
132         return MEMTX_DECODE_ERROR;
133     }
134 
135     /* override requester_id */
136     addr = SMP_IPI_MAILBOX + CORE_BUF_20 + (val & 0x1c);
137     attrs.requester_id = cs->cpu_index;
138     send_ipi_data(&LOONGARCH_CPU(cs)->env, val, addr, attrs);
139     return MEMTX_OK;
140 }
141 
142 static MemTxResult any_send(uint64_t val, MemTxAttrs attrs)
143 {
144     uint32_t cpuid;
145     hwaddr addr;
146     CPUState *cs;
147 
148     cpuid = extract32(val, 16, 10);
149     if (cpuid >= LOONGARCH_MAX_CPUS) {
150         trace_loongarch_ipi_unsupported_cpuid("IOCSR_ANY_SEND", cpuid);
151         return MEMTX_DECODE_ERROR;
152     }
153 
154     cs = ipi_getcpu(cpuid);
155     if (cs == NULL) {
156         return MEMTX_DECODE_ERROR;
157     }
158 
159     /* override requester_id */
160     addr = val & 0xffff;
161     attrs.requester_id = cs->cpu_index;
162     send_ipi_data(&LOONGARCH_CPU(cs)->env, val, addr, attrs);
163     return MEMTX_OK;
164 }
165 
166 static MemTxResult loongarch_ipi_writel(void *opaque, hwaddr addr, uint64_t val,
167                                         unsigned size, MemTxAttrs attrs)
168 {
169     LoongArchIPI *ipi = opaque;
170     IPICore *s;
171     int index = 0;
172     uint32_t cpuid;
173     uint8_t vector;
174     CPUState *cs;
175 
176     s = &ipi->cpu[attrs.requester_id];
177     addr &= 0xff;
178     trace_loongarch_ipi_write(size, (uint64_t)addr, val);
179     switch (addr) {
180     case CORE_STATUS_OFF:
181         qemu_log_mask(LOG_GUEST_ERROR, "can not be written");
182         break;
183     case CORE_EN_OFF:
184         s->en = val;
185         break;
186     case CORE_SET_OFF:
187         s->status |= val;
188         if (s->status != 0 && (s->status & s->en) != 0) {
189             qemu_irq_raise(s->irq);
190         }
191         break;
192     case CORE_CLEAR_OFF:
193         s->status &= ~val;
194         if (s->status == 0 && s->en != 0) {
195             qemu_irq_lower(s->irq);
196         }
197         break;
198     case CORE_BUF_20 ... CORE_BUF_38 + 4:
199         index = (addr - CORE_BUF_20) >> 2;
200         s->buf[index] = val;
201         break;
202     case IOCSR_IPI_SEND:
203         cpuid = extract32(val, 16, 10);
204         if (cpuid >= LOONGARCH_MAX_CPUS) {
205             trace_loongarch_ipi_unsupported_cpuid("IOCSR_IPI_SEND", cpuid);
206             return MEMTX_DECODE_ERROR;
207         }
208 
209         /* IPI status vector */
210         vector = extract8(val, 0, 5);
211         cs = ipi_getcpu(cpuid);
212         if (cs == NULL) {
213             return MEMTX_DECODE_ERROR;
214         }
215 
216         /* override requester_id */
217         attrs.requester_id = cs->cpu_index;
218         loongarch_ipi_writel(ipi, CORE_SET_OFF, BIT(vector), 4, attrs);
219         break;
220     default:
221         qemu_log_mask(LOG_UNIMP, "invalid write: %x", (uint32_t)addr);
222         break;
223     }
224 
225     return MEMTX_OK;
226 }
227 
228 static const MemoryRegionOps loongarch_ipi_ops = {
229     .read_with_attrs = loongarch_ipi_readl,
230     .write_with_attrs = loongarch_ipi_writel,
231     .impl.min_access_size = 4,
232     .impl.max_access_size = 4,
233     .valid.min_access_size = 4,
234     .valid.max_access_size = 8,
235     .endianness = DEVICE_LITTLE_ENDIAN,
236 };
237 
238 /* mail send and any send only support writeq */
239 static MemTxResult loongarch_ipi_writeq(void *opaque, hwaddr addr, uint64_t val,
240                                         unsigned size, MemTxAttrs attrs)
241 {
242     MemTxResult ret = MEMTX_OK;
243 
244     addr &= 0xfff;
245     switch (addr) {
246     case MAIL_SEND_OFFSET:
247         ret = mail_send(val, attrs);
248         break;
249     case ANY_SEND_OFFSET:
250         ret = any_send(val, attrs);
251         break;
252     default:
253        break;
254     }
255 
256     return ret;
257 }
258 
259 static const MemoryRegionOps loongarch_ipi64_ops = {
260     .write_with_attrs = loongarch_ipi_writeq,
261     .impl.min_access_size = 8,
262     .impl.max_access_size = 8,
263     .valid.min_access_size = 8,
264     .valid.max_access_size = 8,
265     .endianness = DEVICE_LITTLE_ENDIAN,
266 };
267 
268 static void loongarch_ipi_realize(DeviceState *dev, Error **errp)
269 {
270     LoongArchIPI *s = LOONGARCH_IPI(dev);
271     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
272     int i;
273 
274     if (s->num_cpu == 0) {
275         error_setg(errp, "num-cpu must be at least 1");
276         return;
277     }
278 
279     memory_region_init_io(&s->ipi_iocsr_mem, OBJECT(dev), &loongarch_ipi_ops,
280                           s, "loongarch_ipi_iocsr", 0x48);
281 
282     /* loongarch_ipi_iocsr performs re-entrant IO through ipi_send */
283     s->ipi_iocsr_mem.disable_reentrancy_guard = true;
284 
285     sysbus_init_mmio(sbd, &s->ipi_iocsr_mem);
286 
287     memory_region_init_io(&s->ipi64_iocsr_mem, OBJECT(dev),
288                           &loongarch_ipi64_ops,
289                           s, "loongarch_ipi64_iocsr", 0x118);
290     sysbus_init_mmio(sbd, &s->ipi64_iocsr_mem);
291 
292     s->cpu = g_new0(IPICore, s->num_cpu);
293     if (s->cpu == NULL) {
294         error_setg(errp, "Memory allocation for ExtIOICore faile");
295         return;
296     }
297 
298     for (i = 0; i < s->num_cpu; i++) {
299         qdev_init_gpio_out(dev, &s->cpu[i].irq, 1);
300     }
301 }
302 
303 static const VMStateDescription vmstate_ipi_core = {
304     .name = "ipi-single",
305     .version_id = 2,
306     .minimum_version_id = 2,
307     .fields = (const VMStateField[]) {
308         VMSTATE_UINT32(status, IPICore),
309         VMSTATE_UINT32(en, IPICore),
310         VMSTATE_UINT32(set, IPICore),
311         VMSTATE_UINT32(clear, IPICore),
312         VMSTATE_UINT32_ARRAY(buf, IPICore, IPI_MBX_NUM * 2),
313         VMSTATE_END_OF_LIST()
314     }
315 };
316 
317 static const VMStateDescription vmstate_loongarch_ipi = {
318     .name = TYPE_LOONGARCH_IPI,
319     .version_id = 2,
320     .minimum_version_id = 2,
321     .fields = (const VMStateField[]) {
322         VMSTATE_STRUCT_VARRAY_POINTER_UINT32(cpu, LoongArchIPI, num_cpu,
323                          vmstate_ipi_core, IPICore),
324         VMSTATE_END_OF_LIST()
325     }
326 };
327 
328 static Property ipi_properties[] = {
329     DEFINE_PROP_UINT32("num-cpu", LoongArchIPI, num_cpu, 1),
330     DEFINE_PROP_END_OF_LIST(),
331 };
332 
333 static void loongarch_ipi_class_init(ObjectClass *klass, void *data)
334 {
335     DeviceClass *dc = DEVICE_CLASS(klass);
336 
337     dc->realize = loongarch_ipi_realize;
338     device_class_set_props(dc, ipi_properties);
339     dc->vmsd = &vmstate_loongarch_ipi;
340 }
341 
342 static void loongarch_ipi_finalize(Object *obj)
343 {
344     LoongArchIPI *s = LOONGARCH_IPI(obj);
345 
346     g_free(s->cpu);
347 }
348 
349 static const TypeInfo loongarch_ipi_info = {
350     .name          = TYPE_LOONGARCH_IPI,
351     .parent        = TYPE_SYS_BUS_DEVICE,
352     .instance_size = sizeof(LoongArchIPI),
353     .class_init    = loongarch_ipi_class_init,
354     .instance_finalize = loongarch_ipi_finalize,
355 };
356 
357 static void loongarch_ipi_register_types(void)
358 {
359     type_register_static(&loongarch_ipi_info);
360 }
361 
362 type_init(loongarch_ipi_register_types)
363