xref: /openbmc/qemu/hw/intc/slavio_intctl.c (revision 4921d0a7)
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 "migration/vmstate.h"
27 #include "monitor/monitor.h"
28 #include "qemu/module.h"
29 #include "hw/sysbus.h"
30 #include "hw/intc/intc.h"
31 #include "hw/irq.h"
32 #include "trace.h"
33 #include "qom/object.h"
34 
35 //#define DEBUG_IRQ_COUNT
36 
37 /*
38  * Registers of interrupt controller in sun4m.
39  *
40  * This is the interrupt controller part of chip STP2001 (Slave I/O), also
41  * produced as NCR89C105. See
42  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C105.txt
43  *
44  * There is a system master controller and one for each cpu.
45  *
46  */
47 
48 #define MAX_CPUS 16
49 #define MAX_PILS 16
50 
51 struct SLAVIO_INTCTLState;
52 
53 typedef struct SLAVIO_CPUINTCTLState {
54     MemoryRegion iomem;
55     struct SLAVIO_INTCTLState *master;
56     uint32_t intreg_pending;
57     uint32_t cpu;
58     uint32_t irl_out;
59 } SLAVIO_CPUINTCTLState;
60 
61 #define TYPE_SLAVIO_INTCTL "slavio_intctl"
62 OBJECT_DECLARE_SIMPLE_TYPE(SLAVIO_INTCTLState, SLAVIO_INTCTL)
63 
64 struct SLAVIO_INTCTLState {
65     SysBusDevice parent_obj;
66 
67     MemoryRegion iomem;
68 #ifdef DEBUG_IRQ_COUNT
69     uint64_t irq_count[32];
70 #endif
71     qemu_irq cpu_irqs[MAX_CPUS][MAX_PILS];
72     SLAVIO_CPUINTCTLState slaves[MAX_CPUS];
73     uint32_t intregm_pending;
74     uint32_t intregm_disabled;
75     uint32_t target_cpu;
76 };
77 
78 #define INTCTL_MAXADDR 0xf
79 #define INTCTL_SIZE (INTCTL_MAXADDR + 1)
80 #define INTCTLM_SIZE 0x14
81 #define MASTER_IRQ_MASK ~0x0fa2007f
82 #define MASTER_DISABLE 0x80000000
83 #define CPU_SOFTIRQ_MASK 0xfffe0000
84 #define CPU_IRQ_INT15_IN (1 << 15)
85 #define CPU_IRQ_TIMER_IN (1 << 14)
86 
87 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs);
88 
89 // per-cpu interrupt controller
90 static uint64_t slavio_intctl_mem_readl(void *opaque, hwaddr addr,
91                                         unsigned size)
92 {
93     SLAVIO_CPUINTCTLState *s = opaque;
94     uint32_t saddr, ret;
95 
96     saddr = addr >> 2;
97     switch (saddr) {
98     case 0:
99         ret = s->intreg_pending;
100         break;
101     default:
102         ret = 0;
103         break;
104     }
105     trace_slavio_intctl_mem_readl(s->cpu, addr, ret);
106 
107     return ret;
108 }
109 
110 static void slavio_intctl_mem_writel(void *opaque, hwaddr addr,
111                                      uint64_t val, unsigned size)
112 {
113     SLAVIO_CPUINTCTLState *s = opaque;
114     uint32_t saddr;
115 
116     saddr = addr >> 2;
117     trace_slavio_intctl_mem_writel(s->cpu, addr, val);
118     switch (saddr) {
119     case 1: // clear pending softints
120         val &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN;
121         s->intreg_pending &= ~val;
122         slavio_check_interrupts(s->master, 1);
123         trace_slavio_intctl_mem_writel_clear(s->cpu, val, s->intreg_pending);
124         break;
125     case 2: // set softint
126         val &= CPU_SOFTIRQ_MASK;
127         s->intreg_pending |= val;
128         slavio_check_interrupts(s->master, 1);
129         trace_slavio_intctl_mem_writel_set(s->cpu, val, s->intreg_pending);
130         break;
131     default:
132         break;
133     }
134 }
135 
136 static const MemoryRegionOps slavio_intctl_mem_ops = {
137     .read = slavio_intctl_mem_readl,
138     .write = slavio_intctl_mem_writel,
139     .endianness = DEVICE_NATIVE_ENDIAN,
140     .valid = {
141         .min_access_size = 4,
142         .max_access_size = 4,
143     },
144 };
145 
146 // master system interrupt controller
147 static uint64_t slavio_intctlm_mem_readl(void *opaque, hwaddr addr,
148                                          unsigned size)
149 {
150     SLAVIO_INTCTLState *s = opaque;
151     uint32_t saddr, ret;
152 
153     saddr = addr >> 2;
154     switch (saddr) {
155     case 0:
156         ret = s->intregm_pending & ~MASTER_DISABLE;
157         break;
158     case 1:
159         ret = s->intregm_disabled & MASTER_IRQ_MASK;
160         break;
161     case 4:
162         ret = s->target_cpu;
163         break;
164     default:
165         ret = 0;
166         break;
167     }
168     trace_slavio_intctlm_mem_readl(addr, ret);
169 
170     return ret;
171 }
172 
173 static void slavio_intctlm_mem_writel(void *opaque, hwaddr addr,
174                                       uint64_t val, unsigned size)
175 {
176     SLAVIO_INTCTLState *s = opaque;
177     uint32_t saddr;
178 
179     saddr = addr >> 2;
180     trace_slavio_intctlm_mem_writel(addr, val);
181     switch (saddr) {
182     case 2: // clear (enable)
183         // Force clear unused bits
184         val &= MASTER_IRQ_MASK;
185         s->intregm_disabled &= ~val;
186         trace_slavio_intctlm_mem_writel_enable(val, s->intregm_disabled);
187         slavio_check_interrupts(s, 1);
188         break;
189     case 3: // set (disable; doesn't affect pending)
190         // Force clear unused bits
191         val &= MASTER_IRQ_MASK;
192         s->intregm_disabled |= val;
193         slavio_check_interrupts(s, 1);
194         trace_slavio_intctlm_mem_writel_disable(val, s->intregm_disabled);
195         break;
196     case 4:
197         s->target_cpu = val & (MAX_CPUS - 1);
198         slavio_check_interrupts(s, 1);
199         trace_slavio_intctlm_mem_writel_target(s->target_cpu);
200         break;
201     default:
202         break;
203     }
204 }
205 
206 static const MemoryRegionOps slavio_intctlm_mem_ops = {
207     .read = slavio_intctlm_mem_readl,
208     .write = slavio_intctlm_mem_writel,
209     .endianness = DEVICE_NATIVE_ENDIAN,
210     .valid = {
211         .min_access_size = 4,
212         .max_access_size = 4,
213     },
214 };
215 
216 static const uint32_t intbit_to_level[] = {
217     2, 3, 5, 7, 9, 11, 13, 2,   3, 5, 7, 9, 11, 13, 12, 12,
218     6, 13, 4, 10, 8, 9, 11, 0,  0, 0, 0, 15, 15, 15, 15, 0,
219 };
220 
221 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs)
222 {
223     uint32_t pending = s->intregm_pending, pil_pending;
224     unsigned int i, j;
225 
226     pending &= ~s->intregm_disabled;
227 
228     trace_slavio_check_interrupts(pending, s->intregm_disabled);
229     for (i = 0; i < MAX_CPUS; i++) {
230         pil_pending = 0;
231 
232         /* If we are the current interrupt target, get hard interrupts */
233         if (pending && !(s->intregm_disabled & MASTER_DISABLE) &&
234             (i == s->target_cpu)) {
235             for (j = 0; j < 32; j++) {
236                 if ((pending & (1 << j)) && intbit_to_level[j]) {
237                     pil_pending |= 1 << intbit_to_level[j];
238                 }
239             }
240         }
241 
242         /* Calculate current pending hard interrupts for display */
243         s->slaves[i].intreg_pending &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN |
244             CPU_IRQ_TIMER_IN;
245         if (i == s->target_cpu) {
246             for (j = 0; j < 32; j++) {
247                 if ((s->intregm_pending & (1U << j)) && intbit_to_level[j]) {
248                     s->slaves[i].intreg_pending |= 1 << intbit_to_level[j];
249                 }
250             }
251         }
252 
253         /* Level 15 and CPU timer interrupts are only masked when
254            the MASTER_DISABLE bit is set */
255         if (!(s->intregm_disabled & MASTER_DISABLE)) {
256             pil_pending |= s->slaves[i].intreg_pending &
257                 (CPU_IRQ_INT15_IN | CPU_IRQ_TIMER_IN);
258         }
259 
260         /* Add soft interrupts */
261         pil_pending |= (s->slaves[i].intreg_pending & CPU_SOFTIRQ_MASK) >> 16;
262 
263         if (set_irqs) {
264             /* Since there is not really an interrupt 0 (and pil_pending
265              * and irl_out bit zero are thus always zero) there is no need
266              * to do anything with cpu_irqs[i][0] and it is OK not to do
267              * the j=0 iteration of this loop.
268              */
269             for (j = MAX_PILS-1; j > 0; j--) {
270                 if (pil_pending & (1 << j)) {
271                     if (!(s->slaves[i].irl_out & (1 << j))) {
272                         qemu_irq_raise(s->cpu_irqs[i][j]);
273                     }
274                 } else {
275                     if (s->slaves[i].irl_out & (1 << j)) {
276                         qemu_irq_lower(s->cpu_irqs[i][j]);
277                     }
278                 }
279             }
280         }
281         s->slaves[i].irl_out = pil_pending;
282     }
283 }
284 
285 /*
286  * "irq" here is the bit number in the system interrupt register to
287  * separate serial and keyboard interrupts sharing a level.
288  */
289 static void slavio_set_irq(void *opaque, int irq, int level)
290 {
291     SLAVIO_INTCTLState *s = opaque;
292     uint32_t mask = 1 << irq;
293     uint32_t pil = intbit_to_level[irq];
294     unsigned int i;
295 
296     trace_slavio_set_irq(s->target_cpu, irq, pil, level);
297     if (pil > 0) {
298         if (level) {
299 #ifdef DEBUG_IRQ_COUNT
300             s->irq_count[pil]++;
301 #endif
302             s->intregm_pending |= mask;
303             if (pil == 15) {
304                 for (i = 0; i < MAX_CPUS; i++) {
305                     s->slaves[i].intreg_pending |= 1 << pil;
306                 }
307             }
308         } else {
309             s->intregm_pending &= ~mask;
310             if (pil == 15) {
311                 for (i = 0; i < MAX_CPUS; i++) {
312                     s->slaves[i].intreg_pending &= ~(1 << pil);
313                 }
314             }
315         }
316         slavio_check_interrupts(s, 1);
317     }
318 }
319 
320 static void slavio_set_timer_irq_cpu(void *opaque, int cpu, int level)
321 {
322     SLAVIO_INTCTLState *s = opaque;
323 
324     trace_slavio_set_timer_irq_cpu(cpu, level);
325 
326     if (level) {
327         s->slaves[cpu].intreg_pending |= CPU_IRQ_TIMER_IN;
328     } else {
329         s->slaves[cpu].intreg_pending &= ~CPU_IRQ_TIMER_IN;
330     }
331 
332     slavio_check_interrupts(s, 1);
333 }
334 
335 static void slavio_set_irq_all(void *opaque, int irq, int level)
336 {
337     if (irq < 32) {
338         slavio_set_irq(opaque, irq, level);
339     } else {
340         slavio_set_timer_irq_cpu(opaque, irq - 32, level);
341     }
342 }
343 
344 static int vmstate_intctl_post_load(void *opaque, int version_id)
345 {
346     SLAVIO_INTCTLState *s = opaque;
347 
348     slavio_check_interrupts(s, 0);
349     return 0;
350 }
351 
352 static const VMStateDescription vmstate_intctl_cpu = {
353     .name ="slavio_intctl_cpu",
354     .version_id = 1,
355     .minimum_version_id = 1,
356     .fields = (const VMStateField[]) {
357         VMSTATE_UINT32(intreg_pending, SLAVIO_CPUINTCTLState),
358         VMSTATE_END_OF_LIST()
359     }
360 };
361 
362 static const VMStateDescription vmstate_intctl = {
363     .name ="slavio_intctl",
364     .version_id = 1,
365     .minimum_version_id = 1,
366     .post_load = vmstate_intctl_post_load,
367     .fields = (const VMStateField[]) {
368         VMSTATE_STRUCT_ARRAY(slaves, SLAVIO_INTCTLState, MAX_CPUS, 1,
369                              vmstate_intctl_cpu, SLAVIO_CPUINTCTLState),
370         VMSTATE_UINT32(intregm_pending, SLAVIO_INTCTLState),
371         VMSTATE_UINT32(intregm_disabled, SLAVIO_INTCTLState),
372         VMSTATE_UINT32(target_cpu, SLAVIO_INTCTLState),
373         VMSTATE_END_OF_LIST()
374     }
375 };
376 
377 static void slavio_intctl_reset(DeviceState *d)
378 {
379     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(d);
380     int i;
381 
382     for (i = 0; i < MAX_CPUS; i++) {
383         s->slaves[i].intreg_pending = 0;
384         s->slaves[i].irl_out = 0;
385     }
386     s->intregm_disabled = ~MASTER_IRQ_MASK;
387     s->intregm_pending = 0;
388     s->target_cpu = 0;
389     slavio_check_interrupts(s, 0);
390 }
391 
392 #ifdef DEBUG_IRQ_COUNT
393 static bool slavio_intctl_get_statistics(InterruptStatsProvider *obj,
394                                          uint64_t **irq_counts,
395                                          unsigned int *nb_irqs)
396 {
397     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(obj);
398     *irq_counts = s->irq_count;
399     *nb_irqs = ARRAY_SIZE(s->irq_count);
400     return true;
401 }
402 #endif
403 
404 static void slavio_intctl_print_info(InterruptStatsProvider *obj, Monitor *mon)
405 {
406     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(obj);
407     int i;
408 
409     for (i = 0; i < MAX_CPUS; i++) {
410         monitor_printf(mon, "per-cpu %d: pending 0x%08x\n", i,
411                        s->slaves[i].intreg_pending);
412     }
413     monitor_printf(mon, "master: pending 0x%08x, disabled 0x%08x\n",
414                    s->intregm_pending, s->intregm_disabled);
415 }
416 
417 static void slavio_intctl_init(Object *obj)
418 {
419     DeviceState *dev = DEVICE(obj);
420     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(obj);
421     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
422     unsigned int i, j;
423     char slave_name[45];
424 
425     qdev_init_gpio_in(dev, slavio_set_irq_all, 32 + MAX_CPUS);
426     memory_region_init_io(&s->iomem, obj, &slavio_intctlm_mem_ops, s,
427                           "master-interrupt-controller", INTCTLM_SIZE);
428     sysbus_init_mmio(sbd, &s->iomem);
429 
430     for (i = 0; i < MAX_CPUS; i++) {
431         snprintf(slave_name, sizeof(slave_name),
432                  "slave-interrupt-controller-%i", i);
433         for (j = 0; j < MAX_PILS; j++) {
434             sysbus_init_irq(sbd, &s->cpu_irqs[i][j]);
435         }
436         memory_region_init_io(&s->slaves[i].iomem, OBJECT(s),
437                               &slavio_intctl_mem_ops,
438                               &s->slaves[i], slave_name, INTCTL_SIZE);
439         sysbus_init_mmio(sbd, &s->slaves[i].iomem);
440         s->slaves[i].cpu = i;
441         s->slaves[i].master = s;
442     }
443 }
444 
445 static void slavio_intctl_class_init(ObjectClass *klass, void *data)
446 {
447     DeviceClass *dc = DEVICE_CLASS(klass);
448     InterruptStatsProviderClass *ic = INTERRUPT_STATS_PROVIDER_CLASS(klass);
449 
450     dc->reset = slavio_intctl_reset;
451     dc->vmsd = &vmstate_intctl;
452 #ifdef DEBUG_IRQ_COUNT
453     ic->get_statistics = slavio_intctl_get_statistics;
454 #endif
455     ic->print_info = slavio_intctl_print_info;
456 }
457 
458 static const TypeInfo slavio_intctl_info = {
459     .name          = TYPE_SLAVIO_INTCTL,
460     .parent        = TYPE_SYS_BUS_DEVICE,
461     .instance_size = sizeof(SLAVIO_INTCTLState),
462     .instance_init = slavio_intctl_init,
463     .class_init    = slavio_intctl_class_init,
464     .interfaces = (InterfaceInfo[]) {
465         { TYPE_INTERRUPT_STATS_PROVIDER },
466         { }
467     },
468 };
469 
470 static void slavio_intctl_register_types(void)
471 {
472     type_register_static(&slavio_intctl_info);
473 }
474 
475 type_init(slavio_intctl_register_types)
476