xref: /openbmc/qemu/hw/intc/loongson_ipi.c (revision ba379542)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Loongson 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/loongson_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 #ifdef TARGET_LOONGARCH64
19 #include "target/loongarch/cpu.h"
20 #endif
21 #ifdef TARGET_MIPS
22 #include "target/mips/cpu.h"
23 #endif
24 #include "trace.h"
25 
26 static MemTxResult loongson_ipi_readl(void *opaque, hwaddr addr,
27                                        uint64_t *data,
28                                        unsigned size, MemTxAttrs attrs)
29 {
30     IPICore *s;
31     LoongsonIPI *ipi = opaque;
32     uint64_t ret = 0;
33     int index = 0;
34 
35     s = &ipi->cpu[attrs.requester_id];
36     addr &= 0xff;
37     switch (addr) {
38     case CORE_STATUS_OFF:
39         ret = s->status;
40         break;
41     case CORE_EN_OFF:
42         ret = s->en;
43         break;
44     case CORE_SET_OFF:
45         ret = 0;
46         break;
47     case CORE_CLEAR_OFF:
48         ret = 0;
49         break;
50     case CORE_BUF_20 ... CORE_BUF_38 + 4:
51         index = (addr - CORE_BUF_20) >> 2;
52         ret = s->buf[index];
53         break;
54     default:
55         qemu_log_mask(LOG_UNIMP, "invalid read: %x", (uint32_t)addr);
56         break;
57     }
58 
59     trace_loongson_ipi_read(size, (uint64_t)addr, ret);
60     *data = ret;
61     return MEMTX_OK;
62 }
63 
64 static AddressSpace *get_cpu_iocsr_as(CPUState *cpu)
65 {
66 #ifdef TARGET_LOONGARCH64
67     return LOONGARCH_CPU(cpu)->env.address_space_iocsr;
68 #endif
69 #ifdef TARGET_MIPS
70     if (ase_lcsr_available(&MIPS_CPU(cpu)->env)) {
71         return &MIPS_CPU(cpu)->env.iocsr.as;
72     }
73 #endif
74     return NULL;
75 }
76 
77 static MemTxResult send_ipi_data(CPUState *cpu, uint64_t val, hwaddr addr,
78                           MemTxAttrs attrs)
79 {
80     int i, mask = 0, data = 0;
81     AddressSpace *iocsr_as = get_cpu_iocsr_as(cpu);
82 
83     if (!iocsr_as) {
84         return MEMTX_DECODE_ERROR;
85     }
86 
87     /*
88      * bit 27-30 is mask for byte writing,
89      * if the mask is 0, we need not to do anything.
90      */
91     if ((val >> 27) & 0xf) {
92         data = address_space_ldl(iocsr_as, addr, attrs, NULL);
93         for (i = 0; i < 4; i++) {
94             /* get mask for byte writing */
95             if (val & (0x1 << (27 + i))) {
96                 mask |= 0xff << (i * 8);
97             }
98         }
99     }
100 
101     data &= mask;
102     data |= (val >> 32) & ~mask;
103     address_space_stl(iocsr_as, addr, data, attrs, NULL);
104 
105     return MEMTX_OK;
106 }
107 
108 static int archid_cmp(const void *a, const void *b)
109 {
110    CPUArchId *archid_a = (CPUArchId *)a;
111    CPUArchId *archid_b = (CPUArchId *)b;
112 
113    return archid_a->arch_id - archid_b->arch_id;
114 }
115 
116 static CPUArchId *find_cpu_by_archid(MachineState *ms, uint32_t id)
117 {
118     CPUArchId apic_id, *found_cpu;
119 
120     apic_id.arch_id = id;
121     found_cpu = bsearch(&apic_id, ms->possible_cpus->cpus,
122         ms->possible_cpus->len, sizeof(*ms->possible_cpus->cpus),
123         archid_cmp);
124 
125     return found_cpu;
126 }
127 
128 static CPUState *ipi_getcpu(int arch_id)
129 {
130     MachineState *machine = MACHINE(qdev_get_machine());
131     CPUArchId *archid;
132 
133     archid = find_cpu_by_archid(machine, arch_id);
134     if (archid) {
135         return CPU(archid->cpu);
136     }
137 
138     return NULL;
139 }
140 
141 static MemTxResult mail_send(uint64_t val, MemTxAttrs attrs)
142 {
143     uint32_t cpuid;
144     hwaddr addr;
145     CPUState *cs;
146 
147     cpuid = extract32(val, 16, 10);
148     cs = ipi_getcpu(cpuid);
149     if (cs == NULL) {
150         return MEMTX_DECODE_ERROR;
151     }
152 
153     /* override requester_id */
154     addr = SMP_IPI_MAILBOX + CORE_BUF_20 + (val & 0x1c);
155     attrs.requester_id = cs->cpu_index;
156     return send_ipi_data(cs, val, addr, attrs);
157 }
158 
159 static MemTxResult any_send(uint64_t val, MemTxAttrs attrs)
160 {
161     uint32_t cpuid;
162     hwaddr addr;
163     CPUState *cs;
164 
165     cpuid = extract32(val, 16, 10);
166     cs = ipi_getcpu(cpuid);
167     if (cs == NULL) {
168         return MEMTX_DECODE_ERROR;
169     }
170 
171     /* override requester_id */
172     addr = val & 0xffff;
173     attrs.requester_id = cs->cpu_index;
174     return send_ipi_data(cs, val, addr, attrs);
175 }
176 
177 static MemTxResult loongson_ipi_writel(void *opaque, hwaddr addr, uint64_t val,
178                                         unsigned size, MemTxAttrs attrs)
179 {
180     LoongsonIPI *ipi = opaque;
181     IPICore *s;
182     int index = 0;
183     uint32_t cpuid;
184     uint8_t vector;
185     CPUState *cs;
186 
187     s = &ipi->cpu[attrs.requester_id];
188     addr &= 0xff;
189     trace_loongson_ipi_write(size, (uint64_t)addr, val);
190     switch (addr) {
191     case CORE_STATUS_OFF:
192         qemu_log_mask(LOG_GUEST_ERROR, "can not be written");
193         break;
194     case CORE_EN_OFF:
195         s->en = val;
196         break;
197     case CORE_SET_OFF:
198         s->status |= val;
199         if (s->status != 0 && (s->status & s->en) != 0) {
200             qemu_irq_raise(s->irq);
201         }
202         break;
203     case CORE_CLEAR_OFF:
204         s->status &= ~val;
205         if (s->status == 0 && s->en != 0) {
206             qemu_irq_lower(s->irq);
207         }
208         break;
209     case CORE_BUF_20 ... CORE_BUF_38 + 4:
210         index = (addr - CORE_BUF_20) >> 2;
211         s->buf[index] = val;
212         break;
213     case IOCSR_IPI_SEND:
214         cpuid = extract32(val, 16, 10);
215         /* IPI status vector */
216         vector = extract8(val, 0, 5);
217         cs = ipi_getcpu(cpuid);
218         if (cs == NULL) {
219             return MEMTX_DECODE_ERROR;
220         }
221 
222         /* override requester_id */
223         attrs.requester_id = cs->cpu_index;
224         loongson_ipi_writel(ipi, CORE_SET_OFF, BIT(vector), 4, attrs);
225         break;
226     default:
227         qemu_log_mask(LOG_UNIMP, "invalid write: %x", (uint32_t)addr);
228         break;
229     }
230 
231     return MEMTX_OK;
232 }
233 
234 static const MemoryRegionOps loongson_ipi_ops = {
235     .read_with_attrs = loongson_ipi_readl,
236     .write_with_attrs = loongson_ipi_writel,
237     .impl.min_access_size = 4,
238     .impl.max_access_size = 4,
239     .valid.min_access_size = 4,
240     .valid.max_access_size = 8,
241     .endianness = DEVICE_LITTLE_ENDIAN,
242 };
243 
244 /* mail send and any send only support writeq */
245 static MemTxResult loongson_ipi_writeq(void *opaque, hwaddr addr, uint64_t val,
246                                         unsigned size, MemTxAttrs attrs)
247 {
248     MemTxResult ret = MEMTX_OK;
249 
250     addr &= 0xfff;
251     switch (addr) {
252     case MAIL_SEND_OFFSET:
253         ret = mail_send(val, attrs);
254         break;
255     case ANY_SEND_OFFSET:
256         ret = any_send(val, attrs);
257         break;
258     default:
259        break;
260     }
261 
262     return ret;
263 }
264 
265 static const MemoryRegionOps loongson_ipi64_ops = {
266     .write_with_attrs = loongson_ipi_writeq,
267     .impl.min_access_size = 8,
268     .impl.max_access_size = 8,
269     .valid.min_access_size = 8,
270     .valid.max_access_size = 8,
271     .endianness = DEVICE_LITTLE_ENDIAN,
272 };
273 
274 static void loongson_ipi_realize(DeviceState *dev, Error **errp)
275 {
276     LoongsonIPI *s = LOONGSON_IPI(dev);
277     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
278     int i;
279 
280     if (s->num_cpu == 0) {
281         error_setg(errp, "num-cpu must be at least 1");
282         return;
283     }
284 
285     memory_region_init_io(&s->ipi_iocsr_mem, OBJECT(dev), &loongson_ipi_ops,
286                           s, "loongson_ipi_iocsr", 0x48);
287 
288     /* loongson_ipi_iocsr performs re-entrant IO through ipi_send */
289     s->ipi_iocsr_mem.disable_reentrancy_guard = true;
290 
291     sysbus_init_mmio(sbd, &s->ipi_iocsr_mem);
292 
293     memory_region_init_io(&s->ipi64_iocsr_mem, OBJECT(dev),
294                           &loongson_ipi64_ops,
295                           s, "loongson_ipi64_iocsr", 0x118);
296     sysbus_init_mmio(sbd, &s->ipi64_iocsr_mem);
297 
298     s->cpu = g_new0(IPICore, s->num_cpu);
299     if (s->cpu == NULL) {
300         error_setg(errp, "Memory allocation for ExtIOICore faile");
301         return;
302     }
303 
304     for (i = 0; i < s->num_cpu; i++) {
305         qdev_init_gpio_out(dev, &s->cpu[i].irq, 1);
306     }
307 }
308 
309 static const VMStateDescription vmstate_ipi_core = {
310     .name = "ipi-single",
311     .version_id = 2,
312     .minimum_version_id = 2,
313     .fields = (const VMStateField[]) {
314         VMSTATE_UINT32(status, IPICore),
315         VMSTATE_UINT32(en, IPICore),
316         VMSTATE_UINT32(set, IPICore),
317         VMSTATE_UINT32(clear, IPICore),
318         VMSTATE_UINT32_ARRAY(buf, IPICore, IPI_MBX_NUM * 2),
319         VMSTATE_END_OF_LIST()
320     }
321 };
322 
323 static const VMStateDescription vmstate_loongson_ipi = {
324     .name = TYPE_LOONGSON_IPI,
325     .version_id = 2,
326     .minimum_version_id = 2,
327     .fields = (const VMStateField[]) {
328         VMSTATE_STRUCT_VARRAY_POINTER_UINT32(cpu, LoongsonIPI, num_cpu,
329                          vmstate_ipi_core, IPICore),
330         VMSTATE_END_OF_LIST()
331     }
332 };
333 
334 static Property ipi_properties[] = {
335     DEFINE_PROP_UINT32("num-cpu", LoongsonIPI, num_cpu, 1),
336     DEFINE_PROP_END_OF_LIST(),
337 };
338 
339 static void loongson_ipi_class_init(ObjectClass *klass, void *data)
340 {
341     DeviceClass *dc = DEVICE_CLASS(klass);
342 
343     dc->realize = loongson_ipi_realize;
344     device_class_set_props(dc, ipi_properties);
345     dc->vmsd = &vmstate_loongson_ipi;
346 }
347 
348 static void loongson_ipi_finalize(Object *obj)
349 {
350     LoongsonIPI *s = LOONGSON_IPI(obj);
351 
352     g_free(s->cpu);
353 }
354 
355 static const TypeInfo loongson_ipi_info = {
356     .name          = TYPE_LOONGSON_IPI,
357     .parent        = TYPE_SYS_BUS_DEVICE,
358     .instance_size = sizeof(LoongsonIPI),
359     .class_init    = loongson_ipi_class_init,
360     .instance_finalize = loongson_ipi_finalize,
361 };
362 
363 static void loongson_ipi_register_types(void)
364 {
365     type_register_static(&loongson_ipi_info);
366 }
367 
368 type_init(loongson_ipi_register_types)
369