xref: /openbmc/qemu/hw/intc/loongson_ipi.c (revision 7c08eefc)
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_core_readl(void *opaque, hwaddr addr,
27                                            uint64_t *data,
28                                            unsigned size, MemTxAttrs attrs)
29 {
30     IPICore *s = opaque;
31     uint64_t ret = 0;
32     int index = 0;
33 
34     addr &= 0xff;
35     switch (addr) {
36     case CORE_STATUS_OFF:
37         ret = s->status;
38         break;
39     case CORE_EN_OFF:
40         ret = s->en;
41         break;
42     case CORE_SET_OFF:
43         ret = 0;
44         break;
45     case CORE_CLEAR_OFF:
46         ret = 0;
47         break;
48     case CORE_BUF_20 ... CORE_BUF_38 + 4:
49         index = (addr - CORE_BUF_20) >> 2;
50         ret = s->buf[index];
51         break;
52     default:
53         qemu_log_mask(LOG_UNIMP, "invalid read: %x", (uint32_t)addr);
54         break;
55     }
56 
57     trace_loongson_ipi_read(size, (uint64_t)addr, ret);
58     *data = ret;
59     return MEMTX_OK;
60 }
61 
62 static MemTxResult loongson_ipi_iocsr_readl(void *opaque, hwaddr addr,
63                                             uint64_t *data,
64                                             unsigned size, MemTxAttrs attrs)
65 {
66     LoongsonIPI *ipi = opaque;
67     IPICore *s;
68 
69     if (attrs.requester_id >= ipi->num_cpu) {
70         return MEMTX_DECODE_ERROR;
71     }
72 
73     s = &ipi->cpu[attrs.requester_id];
74     return loongson_ipi_core_readl(s, addr, data, size, attrs);
75 }
76 
77 static AddressSpace *get_cpu_iocsr_as(CPUState *cpu)
78 {
79 #ifdef TARGET_LOONGARCH64
80     return LOONGARCH_CPU(cpu)->env.address_space_iocsr;
81 #endif
82 #ifdef TARGET_MIPS
83     if (ase_lcsr_available(&MIPS_CPU(cpu)->env)) {
84         return &MIPS_CPU(cpu)->env.iocsr.as;
85     }
86 #endif
87     return NULL;
88 }
89 
90 static MemTxResult send_ipi_data(CPUState *cpu, uint64_t val, hwaddr addr,
91                           MemTxAttrs attrs)
92 {
93     int i, mask = 0, data = 0;
94     AddressSpace *iocsr_as = get_cpu_iocsr_as(cpu);
95 
96     if (!iocsr_as) {
97         return MEMTX_DECODE_ERROR;
98     }
99 
100     /*
101      * bit 27-30 is mask for byte writing,
102      * if the mask is 0, we need not to do anything.
103      */
104     if ((val >> 27) & 0xf) {
105         data = address_space_ldl(iocsr_as, addr, attrs, NULL);
106         for (i = 0; i < 4; i++) {
107             /* get mask for byte writing */
108             if (val & (0x1 << (27 + i))) {
109                 mask |= 0xff << (i * 8);
110             }
111         }
112     }
113 
114     data &= mask;
115     data |= (val >> 32) & ~mask;
116     address_space_stl(iocsr_as, addr, data, attrs, NULL);
117 
118     return MEMTX_OK;
119 }
120 
121 static MemTxResult mail_send(uint64_t val, MemTxAttrs attrs)
122 {
123     uint32_t cpuid;
124     hwaddr addr;
125     CPUState *cs;
126 
127     cpuid = extract32(val, 16, 10);
128     cs = cpu_by_arch_id(cpuid);
129     if (cs == NULL) {
130         return MEMTX_DECODE_ERROR;
131     }
132 
133     /* override requester_id */
134     addr = SMP_IPI_MAILBOX + CORE_BUF_20 + (val & 0x1c);
135     attrs.requester_id = cs->cpu_index;
136     return send_ipi_data(cs, val, addr, attrs);
137 }
138 
139 static MemTxResult any_send(uint64_t val, MemTxAttrs attrs)
140 {
141     uint32_t cpuid;
142     hwaddr addr;
143     CPUState *cs;
144 
145     cpuid = extract32(val, 16, 10);
146     cs = cpu_by_arch_id(cpuid);
147     if (cs == NULL) {
148         return MEMTX_DECODE_ERROR;
149     }
150 
151     /* override requester_id */
152     addr = val & 0xffff;
153     attrs.requester_id = cs->cpu_index;
154     return send_ipi_data(cs, val, addr, attrs);
155 }
156 
157 static MemTxResult loongson_ipi_core_writel(void *opaque, hwaddr addr,
158                                             uint64_t val, unsigned size,
159                                             MemTxAttrs attrs)
160 {
161     IPICore *s = opaque;
162     LoongsonIPI *ipi = s->ipi;
163     int index = 0;
164     uint32_t cpuid;
165     uint8_t vector;
166     CPUState *cs;
167 
168     addr &= 0xff;
169     trace_loongson_ipi_write(size, (uint64_t)addr, val);
170     switch (addr) {
171     case CORE_STATUS_OFF:
172         qemu_log_mask(LOG_GUEST_ERROR, "can not be written");
173         break;
174     case CORE_EN_OFF:
175         s->en = val;
176         break;
177     case CORE_SET_OFF:
178         s->status |= val;
179         if (s->status != 0 && (s->status & s->en) != 0) {
180             qemu_irq_raise(s->irq);
181         }
182         break;
183     case CORE_CLEAR_OFF:
184         s->status &= ~val;
185         if (s->status == 0 && s->en != 0) {
186             qemu_irq_lower(s->irq);
187         }
188         break;
189     case CORE_BUF_20 ... CORE_BUF_38 + 4:
190         index = (addr - CORE_BUF_20) >> 2;
191         s->buf[index] = val;
192         break;
193     case IOCSR_IPI_SEND:
194         cpuid = extract32(val, 16, 10);
195         /* IPI status vector */
196         vector = extract8(val, 0, 5);
197         cs = cpu_by_arch_id(cpuid);
198         if (cs == NULL || cs->cpu_index >= ipi->num_cpu) {
199             return MEMTX_DECODE_ERROR;
200         }
201         loongson_ipi_core_writel(&ipi->cpu[cs->cpu_index], CORE_SET_OFF,
202                                  BIT(vector), 4, attrs);
203         break;
204     default:
205         qemu_log_mask(LOG_UNIMP, "invalid write: %x", (uint32_t)addr);
206         break;
207     }
208 
209     return MEMTX_OK;
210 }
211 
212 static MemTxResult loongson_ipi_iocsr_writel(void *opaque, hwaddr addr,
213                                             uint64_t val, unsigned size,
214                                             MemTxAttrs attrs)
215 {
216     LoongsonIPI *ipi = opaque;
217     IPICore *s;
218 
219     if (attrs.requester_id >= ipi->num_cpu) {
220         return MEMTX_DECODE_ERROR;
221     }
222 
223     s = &ipi->cpu[attrs.requester_id];
224     return loongson_ipi_core_writel(s, addr, val, size, attrs);
225 }
226 
227 static const MemoryRegionOps loongson_ipi_core_ops = {
228     .read_with_attrs = loongson_ipi_core_readl,
229     .write_with_attrs = loongson_ipi_core_writel,
230     .impl.min_access_size = 4,
231     .impl.max_access_size = 4,
232     .valid.min_access_size = 4,
233     .valid.max_access_size = 8,
234     .endianness = DEVICE_LITTLE_ENDIAN,
235 };
236 
237 static const MemoryRegionOps loongson_ipi_iocsr_ops = {
238     .read_with_attrs = loongson_ipi_iocsr_readl,
239     .write_with_attrs = loongson_ipi_iocsr_writel,
240     .impl.min_access_size = 4,
241     .impl.max_access_size = 4,
242     .valid.min_access_size = 4,
243     .valid.max_access_size = 8,
244     .endianness = DEVICE_LITTLE_ENDIAN,
245 };
246 
247 /* mail send and any send only support writeq */
248 static MemTxResult loongson_ipi_writeq(void *opaque, hwaddr addr, uint64_t val,
249                                         unsigned size, MemTxAttrs attrs)
250 {
251     MemTxResult ret = MEMTX_OK;
252 
253     addr &= 0xfff;
254     switch (addr) {
255     case MAIL_SEND_OFFSET:
256         ret = mail_send(val, attrs);
257         break;
258     case ANY_SEND_OFFSET:
259         ret = any_send(val, attrs);
260         break;
261     default:
262        break;
263     }
264 
265     return ret;
266 }
267 
268 static const MemoryRegionOps loongson_ipi64_ops = {
269     .write_with_attrs = loongson_ipi_writeq,
270     .impl.min_access_size = 8,
271     .impl.max_access_size = 8,
272     .valid.min_access_size = 8,
273     .valid.max_access_size = 8,
274     .endianness = DEVICE_LITTLE_ENDIAN,
275 };
276 
277 static void loongson_ipi_realize(DeviceState *dev, Error **errp)
278 {
279     LoongsonIPI *s = LOONGSON_IPI(dev);
280     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
281     int i;
282 
283     if (s->num_cpu == 0) {
284         error_setg(errp, "num-cpu must be at least 1");
285         return;
286     }
287 
288     memory_region_init_io(&s->ipi_iocsr_mem, OBJECT(dev),
289                           &loongson_ipi_iocsr_ops,
290                           s, "loongson_ipi_iocsr", 0x48);
291 
292     /* loongson_ipi_iocsr performs re-entrant IO through ipi_send */
293     s->ipi_iocsr_mem.disable_reentrancy_guard = true;
294 
295     sysbus_init_mmio(sbd, &s->ipi_iocsr_mem);
296 
297     memory_region_init_io(&s->ipi64_iocsr_mem, OBJECT(dev),
298                           &loongson_ipi64_ops,
299                           s, "loongson_ipi64_iocsr", 0x118);
300     sysbus_init_mmio(sbd, &s->ipi64_iocsr_mem);
301 
302     s->cpu = g_new0(IPICore, s->num_cpu);
303     if (s->cpu == NULL) {
304         error_setg(errp, "Memory allocation for IPICore faile");
305         return;
306     }
307 
308     for (i = 0; i < s->num_cpu; i++) {
309         s->cpu[i].ipi = s;
310         s->cpu[i].ipi_mmio_mem = g_new0(MemoryRegion, 1);
311         g_autofree char *name = g_strdup_printf("loongson_ipi_cpu%d_mmio", i);
312         memory_region_init_io(s->cpu[i].ipi_mmio_mem, OBJECT(dev),
313                               &loongson_ipi_core_ops, &s->cpu[i], name, 0x48);
314         sysbus_init_mmio(sbd, s->cpu[i].ipi_mmio_mem);
315 
316         qdev_init_gpio_out(dev, &s->cpu[i].irq, 1);
317     }
318 }
319 
320 static const VMStateDescription vmstate_ipi_core = {
321     .name = "ipi-single",
322     .version_id = 2,
323     .minimum_version_id = 2,
324     .fields = (const VMStateField[]) {
325         VMSTATE_UINT32(status, IPICore),
326         VMSTATE_UINT32(en, IPICore),
327         VMSTATE_UINT32(set, IPICore),
328         VMSTATE_UINT32(clear, IPICore),
329         VMSTATE_UINT32_ARRAY(buf, IPICore, IPI_MBX_NUM * 2),
330         VMSTATE_END_OF_LIST()
331     }
332 };
333 
334 static const VMStateDescription vmstate_loongson_ipi = {
335     .name = TYPE_LOONGSON_IPI,
336     .version_id = 2,
337     .minimum_version_id = 2,
338     .fields = (const VMStateField[]) {
339         VMSTATE_STRUCT_VARRAY_POINTER_UINT32(cpu, LoongsonIPI, num_cpu,
340                          vmstate_ipi_core, IPICore),
341         VMSTATE_END_OF_LIST()
342     }
343 };
344 
345 static Property ipi_properties[] = {
346     DEFINE_PROP_UINT32("num-cpu", LoongsonIPI, num_cpu, 1),
347     DEFINE_PROP_END_OF_LIST(),
348 };
349 
350 static void loongson_ipi_class_init(ObjectClass *klass, void *data)
351 {
352     DeviceClass *dc = DEVICE_CLASS(klass);
353 
354     dc->realize = loongson_ipi_realize;
355     device_class_set_props(dc, ipi_properties);
356     dc->vmsd = &vmstate_loongson_ipi;
357 }
358 
359 static void loongson_ipi_finalize(Object *obj)
360 {
361     LoongsonIPI *s = LOONGSON_IPI(obj);
362 
363     g_free(s->cpu);
364 }
365 
366 static const TypeInfo loongson_ipi_info = {
367     .name          = TYPE_LOONGSON_IPI,
368     .parent        = TYPE_SYS_BUS_DEVICE,
369     .instance_size = sizeof(LoongsonIPI),
370     .class_init    = loongson_ipi_class_init,
371     .instance_finalize = loongson_ipi_finalize,
372 };
373 
374 static void loongson_ipi_register_types(void)
375 {
376     type_register_static(&loongson_ipi_info);
377 }
378 
379 type_init(loongson_ipi_register_types)
380