xref: /openbmc/qemu/hw/intc/slavio_intctl.c (revision 9884abee)
1 /*
2  * QEMU Sparc SLAVIO interrupt controller emulation
3  *
4  * Copyright (c) 2003-2005 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "hw/sparc/sun4m.h"
27 #include "monitor/monitor.h"
28 #include "hw/sysbus.h"
29 #include "trace.h"
30 
31 //#define DEBUG_IRQ_COUNT
32 
33 /*
34  * Registers of interrupt controller in sun4m.
35  *
36  * This is the interrupt controller part of chip STP2001 (Slave I/O), also
37  * produced as NCR89C105. See
38  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C105.txt
39  *
40  * There is a system master controller and one for each cpu.
41  *
42  */
43 
44 #define MAX_CPUS 16
45 #define MAX_PILS 16
46 
47 struct SLAVIO_INTCTLState;
48 
49 typedef struct SLAVIO_CPUINTCTLState {
50     MemoryRegion iomem;
51     struct SLAVIO_INTCTLState *master;
52     uint32_t intreg_pending;
53     uint32_t cpu;
54     uint32_t irl_out;
55 } SLAVIO_CPUINTCTLState;
56 
57 #define TYPE_SLAVIO_INTCTL "slavio_intctl"
58 #define SLAVIO_INTCTL(obj) \
59     OBJECT_CHECK(SLAVIO_INTCTLState, (obj), TYPE_SLAVIO_INTCTL)
60 
61 typedef struct SLAVIO_INTCTLState {
62     SysBusDevice parent_obj;
63 
64     MemoryRegion iomem;
65 #ifdef DEBUG_IRQ_COUNT
66     uint64_t irq_count[32];
67 #endif
68     qemu_irq cpu_irqs[MAX_CPUS][MAX_PILS];
69     SLAVIO_CPUINTCTLState slaves[MAX_CPUS];
70     uint32_t intregm_pending;
71     uint32_t intregm_disabled;
72     uint32_t target_cpu;
73 } SLAVIO_INTCTLState;
74 
75 #define INTCTL_MAXADDR 0xf
76 #define INTCTL_SIZE (INTCTL_MAXADDR + 1)
77 #define INTCTLM_SIZE 0x14
78 #define MASTER_IRQ_MASK ~0x0fa2007f
79 #define MASTER_DISABLE 0x80000000
80 #define CPU_SOFTIRQ_MASK 0xfffe0000
81 #define CPU_IRQ_INT15_IN (1 << 15)
82 #define CPU_IRQ_TIMER_IN (1 << 14)
83 
84 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs);
85 
86 // per-cpu interrupt controller
87 static uint64_t slavio_intctl_mem_readl(void *opaque, hwaddr addr,
88                                         unsigned size)
89 {
90     SLAVIO_CPUINTCTLState *s = opaque;
91     uint32_t saddr, ret;
92 
93     saddr = addr >> 2;
94     switch (saddr) {
95     case 0:
96         ret = s->intreg_pending;
97         break;
98     default:
99         ret = 0;
100         break;
101     }
102     trace_slavio_intctl_mem_readl(s->cpu, addr, ret);
103 
104     return ret;
105 }
106 
107 static void slavio_intctl_mem_writel(void *opaque, hwaddr addr,
108                                      uint64_t val, unsigned size)
109 {
110     SLAVIO_CPUINTCTLState *s = opaque;
111     uint32_t saddr;
112 
113     saddr = addr >> 2;
114     trace_slavio_intctl_mem_writel(s->cpu, addr, val);
115     switch (saddr) {
116     case 1: // clear pending softints
117         val &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN;
118         s->intreg_pending &= ~val;
119         slavio_check_interrupts(s->master, 1);
120         trace_slavio_intctl_mem_writel_clear(s->cpu, val, s->intreg_pending);
121         break;
122     case 2: // set softint
123         val &= CPU_SOFTIRQ_MASK;
124         s->intreg_pending |= val;
125         slavio_check_interrupts(s->master, 1);
126         trace_slavio_intctl_mem_writel_set(s->cpu, val, s->intreg_pending);
127         break;
128     default:
129         break;
130     }
131 }
132 
133 static const MemoryRegionOps slavio_intctl_mem_ops = {
134     .read = slavio_intctl_mem_readl,
135     .write = slavio_intctl_mem_writel,
136     .endianness = DEVICE_NATIVE_ENDIAN,
137     .valid = {
138         .min_access_size = 4,
139         .max_access_size = 4,
140     },
141 };
142 
143 // master system interrupt controller
144 static uint64_t slavio_intctlm_mem_readl(void *opaque, hwaddr addr,
145                                          unsigned size)
146 {
147     SLAVIO_INTCTLState *s = opaque;
148     uint32_t saddr, ret;
149 
150     saddr = addr >> 2;
151     switch (saddr) {
152     case 0:
153         ret = s->intregm_pending & ~MASTER_DISABLE;
154         break;
155     case 1:
156         ret = s->intregm_disabled & MASTER_IRQ_MASK;
157         break;
158     case 4:
159         ret = s->target_cpu;
160         break;
161     default:
162         ret = 0;
163         break;
164     }
165     trace_slavio_intctlm_mem_readl(addr, ret);
166 
167     return ret;
168 }
169 
170 static void slavio_intctlm_mem_writel(void *opaque, hwaddr addr,
171                                       uint64_t val, unsigned size)
172 {
173     SLAVIO_INTCTLState *s = opaque;
174     uint32_t saddr;
175 
176     saddr = addr >> 2;
177     trace_slavio_intctlm_mem_writel(addr, val);
178     switch (saddr) {
179     case 2: // clear (enable)
180         // Force clear unused bits
181         val &= MASTER_IRQ_MASK;
182         s->intregm_disabled &= ~val;
183         trace_slavio_intctlm_mem_writel_enable(val, s->intregm_disabled);
184         slavio_check_interrupts(s, 1);
185         break;
186     case 3: // set (disable; doesn't affect pending)
187         // Force clear unused bits
188         val &= MASTER_IRQ_MASK;
189         s->intregm_disabled |= val;
190         slavio_check_interrupts(s, 1);
191         trace_slavio_intctlm_mem_writel_disable(val, s->intregm_disabled);
192         break;
193     case 4:
194         s->target_cpu = val & (MAX_CPUS - 1);
195         slavio_check_interrupts(s, 1);
196         trace_slavio_intctlm_mem_writel_target(s->target_cpu);
197         break;
198     default:
199         break;
200     }
201 }
202 
203 static const MemoryRegionOps slavio_intctlm_mem_ops = {
204     .read = slavio_intctlm_mem_readl,
205     .write = slavio_intctlm_mem_writel,
206     .endianness = DEVICE_NATIVE_ENDIAN,
207     .valid = {
208         .min_access_size = 4,
209         .max_access_size = 4,
210     },
211 };
212 
213 void slavio_pic_info(Monitor *mon, DeviceState *dev)
214 {
215     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(dev);
216     int i;
217 
218     for (i = 0; i < MAX_CPUS; i++) {
219         monitor_printf(mon, "per-cpu %d: pending 0x%08x\n", i,
220                        s->slaves[i].intreg_pending);
221     }
222     monitor_printf(mon, "master: pending 0x%08x, disabled 0x%08x\n",
223                    s->intregm_pending, s->intregm_disabled);
224 }
225 
226 void slavio_irq_info(Monitor *mon, DeviceState *dev)
227 {
228 #ifndef DEBUG_IRQ_COUNT
229     monitor_printf(mon, "irq statistic code not compiled.\n");
230 #else
231     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(dev);
232     int i;
233     int64_t count;
234 
235     s = SLAVIO_INTCTL(dev);
236     monitor_printf(mon, "IRQ statistics:\n");
237     for (i = 0; i < 32; i++) {
238         count = s->irq_count[i];
239         if (count > 0)
240             monitor_printf(mon, "%2d: %" PRId64 "\n", i, count);
241     }
242 #endif
243 }
244 
245 static const uint32_t intbit_to_level[] = {
246     2, 3, 5, 7, 9, 11, 13, 2,   3, 5, 7, 9, 11, 13, 12, 12,
247     6, 13, 4, 10, 8, 9, 11, 0,  0, 0, 0, 15, 15, 15, 15, 0,
248 };
249 
250 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs)
251 {
252     uint32_t pending = s->intregm_pending, pil_pending;
253     unsigned int i, j;
254 
255     pending &= ~s->intregm_disabled;
256 
257     trace_slavio_check_interrupts(pending, s->intregm_disabled);
258     for (i = 0; i < MAX_CPUS; i++) {
259         pil_pending = 0;
260 
261         /* If we are the current interrupt target, get hard interrupts */
262         if (pending && !(s->intregm_disabled & MASTER_DISABLE) &&
263             (i == s->target_cpu)) {
264             for (j = 0; j < 32; j++) {
265                 if ((pending & (1 << j)) && intbit_to_level[j]) {
266                     pil_pending |= 1 << intbit_to_level[j];
267                 }
268             }
269         }
270 
271         /* Calculate current pending hard interrupts for display */
272         s->slaves[i].intreg_pending &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN |
273             CPU_IRQ_TIMER_IN;
274         if (i == s->target_cpu) {
275             for (j = 0; j < 32; j++) {
276                 if ((s->intregm_pending & (1U << j)) && intbit_to_level[j]) {
277                     s->slaves[i].intreg_pending |= 1 << intbit_to_level[j];
278                 }
279             }
280         }
281 
282         /* Level 15 and CPU timer interrupts are only masked when
283            the MASTER_DISABLE bit is set */
284         if (!(s->intregm_disabled & MASTER_DISABLE)) {
285             pil_pending |= s->slaves[i].intreg_pending &
286                 (CPU_IRQ_INT15_IN | CPU_IRQ_TIMER_IN);
287         }
288 
289         /* Add soft interrupts */
290         pil_pending |= (s->slaves[i].intreg_pending & CPU_SOFTIRQ_MASK) >> 16;
291 
292         if (set_irqs) {
293             /* Since there is not really an interrupt 0 (and pil_pending
294              * and irl_out bit zero are thus always zero) there is no need
295              * to do anything with cpu_irqs[i][0] and it is OK not to do
296              * the j=0 iteration of this loop.
297              */
298             for (j = MAX_PILS-1; j > 0; j--) {
299                 if (pil_pending & (1 << j)) {
300                     if (!(s->slaves[i].irl_out & (1 << j))) {
301                         qemu_irq_raise(s->cpu_irqs[i][j]);
302                     }
303                 } else {
304                     if (s->slaves[i].irl_out & (1 << j)) {
305                         qemu_irq_lower(s->cpu_irqs[i][j]);
306                     }
307                 }
308             }
309         }
310         s->slaves[i].irl_out = pil_pending;
311     }
312 }
313 
314 /*
315  * "irq" here is the bit number in the system interrupt register to
316  * separate serial and keyboard interrupts sharing a level.
317  */
318 static void slavio_set_irq(void *opaque, int irq, int level)
319 {
320     SLAVIO_INTCTLState *s = opaque;
321     uint32_t mask = 1 << irq;
322     uint32_t pil = intbit_to_level[irq];
323     unsigned int i;
324 
325     trace_slavio_set_irq(s->target_cpu, irq, pil, level);
326     if (pil > 0) {
327         if (level) {
328 #ifdef DEBUG_IRQ_COUNT
329             s->irq_count[pil]++;
330 #endif
331             s->intregm_pending |= mask;
332             if (pil == 15) {
333                 for (i = 0; i < MAX_CPUS; i++) {
334                     s->slaves[i].intreg_pending |= 1 << pil;
335                 }
336             }
337         } else {
338             s->intregm_pending &= ~mask;
339             if (pil == 15) {
340                 for (i = 0; i < MAX_CPUS; i++) {
341                     s->slaves[i].intreg_pending &= ~(1 << pil);
342                 }
343             }
344         }
345         slavio_check_interrupts(s, 1);
346     }
347 }
348 
349 static void slavio_set_timer_irq_cpu(void *opaque, int cpu, int level)
350 {
351     SLAVIO_INTCTLState *s = opaque;
352 
353     trace_slavio_set_timer_irq_cpu(cpu, level);
354 
355     if (level) {
356         s->slaves[cpu].intreg_pending |= CPU_IRQ_TIMER_IN;
357     } else {
358         s->slaves[cpu].intreg_pending &= ~CPU_IRQ_TIMER_IN;
359     }
360 
361     slavio_check_interrupts(s, 1);
362 }
363 
364 static void slavio_set_irq_all(void *opaque, int irq, int level)
365 {
366     if (irq < 32) {
367         slavio_set_irq(opaque, irq, level);
368     } else {
369         slavio_set_timer_irq_cpu(opaque, irq - 32, level);
370     }
371 }
372 
373 static int vmstate_intctl_post_load(void *opaque, int version_id)
374 {
375     SLAVIO_INTCTLState *s = opaque;
376 
377     slavio_check_interrupts(s, 0);
378     return 0;
379 }
380 
381 static const VMStateDescription vmstate_intctl_cpu = {
382     .name ="slavio_intctl_cpu",
383     .version_id = 1,
384     .minimum_version_id = 1,
385     .fields = (VMStateField[]) {
386         VMSTATE_UINT32(intreg_pending, SLAVIO_CPUINTCTLState),
387         VMSTATE_END_OF_LIST()
388     }
389 };
390 
391 static const VMStateDescription vmstate_intctl = {
392     .name ="slavio_intctl",
393     .version_id = 1,
394     .minimum_version_id = 1,
395     .post_load = vmstate_intctl_post_load,
396     .fields = (VMStateField[]) {
397         VMSTATE_STRUCT_ARRAY(slaves, SLAVIO_INTCTLState, MAX_CPUS, 1,
398                              vmstate_intctl_cpu, SLAVIO_CPUINTCTLState),
399         VMSTATE_UINT32(intregm_pending, SLAVIO_INTCTLState),
400         VMSTATE_UINT32(intregm_disabled, SLAVIO_INTCTLState),
401         VMSTATE_UINT32(target_cpu, SLAVIO_INTCTLState),
402         VMSTATE_END_OF_LIST()
403     }
404 };
405 
406 static void slavio_intctl_reset(DeviceState *d)
407 {
408     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(d);
409     int i;
410 
411     for (i = 0; i < MAX_CPUS; i++) {
412         s->slaves[i].intreg_pending = 0;
413         s->slaves[i].irl_out = 0;
414     }
415     s->intregm_disabled = ~MASTER_IRQ_MASK;
416     s->intregm_pending = 0;
417     s->target_cpu = 0;
418     slavio_check_interrupts(s, 0);
419 }
420 
421 static int slavio_intctl_init1(SysBusDevice *sbd)
422 {
423     DeviceState *dev = DEVICE(sbd);
424     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(dev);
425     unsigned int i, j;
426     char slave_name[45];
427 
428     qdev_init_gpio_in(dev, slavio_set_irq_all, 32 + MAX_CPUS);
429     memory_region_init_io(&s->iomem, OBJECT(s), &slavio_intctlm_mem_ops, s,
430                           "master-interrupt-controller", INTCTLM_SIZE);
431     sysbus_init_mmio(sbd, &s->iomem);
432 
433     for (i = 0; i < MAX_CPUS; i++) {
434         snprintf(slave_name, sizeof(slave_name),
435                  "slave-interrupt-controller-%i", i);
436         for (j = 0; j < MAX_PILS; j++) {
437             sysbus_init_irq(sbd, &s->cpu_irqs[i][j]);
438         }
439         memory_region_init_io(&s->slaves[i].iomem, OBJECT(s),
440                               &slavio_intctl_mem_ops,
441                               &s->slaves[i], slave_name, INTCTL_SIZE);
442         sysbus_init_mmio(sbd, &s->slaves[i].iomem);
443         s->slaves[i].cpu = i;
444         s->slaves[i].master = s;
445     }
446 
447     return 0;
448 }
449 
450 static void slavio_intctl_class_init(ObjectClass *klass, void *data)
451 {
452     DeviceClass *dc = DEVICE_CLASS(klass);
453     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
454 
455     k->init = slavio_intctl_init1;
456     dc->reset = slavio_intctl_reset;
457     dc->vmsd = &vmstate_intctl;
458 }
459 
460 static const TypeInfo slavio_intctl_info = {
461     .name          = TYPE_SLAVIO_INTCTL,
462     .parent        = TYPE_SYS_BUS_DEVICE,
463     .instance_size = sizeof(SLAVIO_INTCTLState),
464     .class_init    = slavio_intctl_class_init,
465 };
466 
467 static void slavio_intctl_register_types(void)
468 {
469     type_register_static(&slavio_intctl_info);
470 }
471 
472 type_init(slavio_intctl_register_types)
473