xref: /openbmc/qemu/hw/intc/slavio_intctl.c (revision 4a09d0bb)
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 "hw/intc/intc.h"
30 #include "trace.h"
31 
32 //#define DEBUG_IRQ_COUNT
33 
34 /*
35  * Registers of interrupt controller in sun4m.
36  *
37  * This is the interrupt controller part of chip STP2001 (Slave I/O), also
38  * produced as NCR89C105. See
39  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C105.txt
40  *
41  * There is a system master controller and one for each cpu.
42  *
43  */
44 
45 #define MAX_CPUS 16
46 #define MAX_PILS 16
47 
48 struct SLAVIO_INTCTLState;
49 
50 typedef struct SLAVIO_CPUINTCTLState {
51     MemoryRegion iomem;
52     struct SLAVIO_INTCTLState *master;
53     uint32_t intreg_pending;
54     uint32_t cpu;
55     uint32_t irl_out;
56 } SLAVIO_CPUINTCTLState;
57 
58 #define TYPE_SLAVIO_INTCTL "slavio_intctl"
59 #define SLAVIO_INTCTL(obj) \
60     OBJECT_CHECK(SLAVIO_INTCTLState, (obj), TYPE_SLAVIO_INTCTL)
61 
62 typedef struct SLAVIO_INTCTLState {
63     SysBusDevice parent_obj;
64 
65     MemoryRegion iomem;
66 #ifdef DEBUG_IRQ_COUNT
67     uint64_t irq_count[32];
68 #endif
69     qemu_irq cpu_irqs[MAX_CPUS][MAX_PILS];
70     SLAVIO_CPUINTCTLState slaves[MAX_CPUS];
71     uint32_t intregm_pending;
72     uint32_t intregm_disabled;
73     uint32_t target_cpu;
74 } SLAVIO_INTCTLState;
75 
76 #define INTCTL_MAXADDR 0xf
77 #define INTCTL_SIZE (INTCTL_MAXADDR + 1)
78 #define INTCTLM_SIZE 0x14
79 #define MASTER_IRQ_MASK ~0x0fa2007f
80 #define MASTER_DISABLE 0x80000000
81 #define CPU_SOFTIRQ_MASK 0xfffe0000
82 #define CPU_IRQ_INT15_IN (1 << 15)
83 #define CPU_IRQ_TIMER_IN (1 << 14)
84 
85 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs);
86 
87 // per-cpu interrupt controller
88 static uint64_t slavio_intctl_mem_readl(void *opaque, hwaddr addr,
89                                         unsigned size)
90 {
91     SLAVIO_CPUINTCTLState *s = opaque;
92     uint32_t saddr, ret;
93 
94     saddr = addr >> 2;
95     switch (saddr) {
96     case 0:
97         ret = s->intreg_pending;
98         break;
99     default:
100         ret = 0;
101         break;
102     }
103     trace_slavio_intctl_mem_readl(s->cpu, addr, ret);
104 
105     return ret;
106 }
107 
108 static void slavio_intctl_mem_writel(void *opaque, hwaddr addr,
109                                      uint64_t val, unsigned size)
110 {
111     SLAVIO_CPUINTCTLState *s = opaque;
112     uint32_t saddr;
113 
114     saddr = addr >> 2;
115     trace_slavio_intctl_mem_writel(s->cpu, addr, val);
116     switch (saddr) {
117     case 1: // clear pending softints
118         val &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN;
119         s->intreg_pending &= ~val;
120         slavio_check_interrupts(s->master, 1);
121         trace_slavio_intctl_mem_writel_clear(s->cpu, val, s->intreg_pending);
122         break;
123     case 2: // set softint
124         val &= CPU_SOFTIRQ_MASK;
125         s->intreg_pending |= val;
126         slavio_check_interrupts(s->master, 1);
127         trace_slavio_intctl_mem_writel_set(s->cpu, val, s->intreg_pending);
128         break;
129     default:
130         break;
131     }
132 }
133 
134 static const MemoryRegionOps slavio_intctl_mem_ops = {
135     .read = slavio_intctl_mem_readl,
136     .write = slavio_intctl_mem_writel,
137     .endianness = DEVICE_NATIVE_ENDIAN,
138     .valid = {
139         .min_access_size = 4,
140         .max_access_size = 4,
141     },
142 };
143 
144 // master system interrupt controller
145 static uint64_t slavio_intctlm_mem_readl(void *opaque, hwaddr addr,
146                                          unsigned size)
147 {
148     SLAVIO_INTCTLState *s = opaque;
149     uint32_t saddr, ret;
150 
151     saddr = addr >> 2;
152     switch (saddr) {
153     case 0:
154         ret = s->intregm_pending & ~MASTER_DISABLE;
155         break;
156     case 1:
157         ret = s->intregm_disabled & MASTER_IRQ_MASK;
158         break;
159     case 4:
160         ret = s->target_cpu;
161         break;
162     default:
163         ret = 0;
164         break;
165     }
166     trace_slavio_intctlm_mem_readl(addr, ret);
167 
168     return ret;
169 }
170 
171 static void slavio_intctlm_mem_writel(void *opaque, hwaddr addr,
172                                       uint64_t val, unsigned size)
173 {
174     SLAVIO_INTCTLState *s = opaque;
175     uint32_t saddr;
176 
177     saddr = addr >> 2;
178     trace_slavio_intctlm_mem_writel(addr, val);
179     switch (saddr) {
180     case 2: // clear (enable)
181         // Force clear unused bits
182         val &= MASTER_IRQ_MASK;
183         s->intregm_disabled &= ~val;
184         trace_slavio_intctlm_mem_writel_enable(val, s->intregm_disabled);
185         slavio_check_interrupts(s, 1);
186         break;
187     case 3: // set (disable; doesn't affect pending)
188         // Force clear unused bits
189         val &= MASTER_IRQ_MASK;
190         s->intregm_disabled |= val;
191         slavio_check_interrupts(s, 1);
192         trace_slavio_intctlm_mem_writel_disable(val, s->intregm_disabled);
193         break;
194     case 4:
195         s->target_cpu = val & (MAX_CPUS - 1);
196         slavio_check_interrupts(s, 1);
197         trace_slavio_intctlm_mem_writel_target(s->target_cpu);
198         break;
199     default:
200         break;
201     }
202 }
203 
204 static const MemoryRegionOps slavio_intctlm_mem_ops = {
205     .read = slavio_intctlm_mem_readl,
206     .write = slavio_intctlm_mem_writel,
207     .endianness = DEVICE_NATIVE_ENDIAN,
208     .valid = {
209         .min_access_size = 4,
210         .max_access_size = 4,
211     },
212 };
213 
214 static const uint32_t intbit_to_level[] = {
215     2, 3, 5, 7, 9, 11, 13, 2,   3, 5, 7, 9, 11, 13, 12, 12,
216     6, 13, 4, 10, 8, 9, 11, 0,  0, 0, 0, 15, 15, 15, 15, 0,
217 };
218 
219 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs)
220 {
221     uint32_t pending = s->intregm_pending, pil_pending;
222     unsigned int i, j;
223 
224     pending &= ~s->intregm_disabled;
225 
226     trace_slavio_check_interrupts(pending, s->intregm_disabled);
227     for (i = 0; i < MAX_CPUS; i++) {
228         pil_pending = 0;
229 
230         /* If we are the current interrupt target, get hard interrupts */
231         if (pending && !(s->intregm_disabled & MASTER_DISABLE) &&
232             (i == s->target_cpu)) {
233             for (j = 0; j < 32; j++) {
234                 if ((pending & (1 << j)) && intbit_to_level[j]) {
235                     pil_pending |= 1 << intbit_to_level[j];
236                 }
237             }
238         }
239 
240         /* Calculate current pending hard interrupts for display */
241         s->slaves[i].intreg_pending &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN |
242             CPU_IRQ_TIMER_IN;
243         if (i == s->target_cpu) {
244             for (j = 0; j < 32; j++) {
245                 if ((s->intregm_pending & (1U << j)) && intbit_to_level[j]) {
246                     s->slaves[i].intreg_pending |= 1 << intbit_to_level[j];
247                 }
248             }
249         }
250 
251         /* Level 15 and CPU timer interrupts are only masked when
252            the MASTER_DISABLE bit is set */
253         if (!(s->intregm_disabled & MASTER_DISABLE)) {
254             pil_pending |= s->slaves[i].intreg_pending &
255                 (CPU_IRQ_INT15_IN | CPU_IRQ_TIMER_IN);
256         }
257 
258         /* Add soft interrupts */
259         pil_pending |= (s->slaves[i].intreg_pending & CPU_SOFTIRQ_MASK) >> 16;
260 
261         if (set_irqs) {
262             /* Since there is not really an interrupt 0 (and pil_pending
263              * and irl_out bit zero are thus always zero) there is no need
264              * to do anything with cpu_irqs[i][0] and it is OK not to do
265              * the j=0 iteration of this loop.
266              */
267             for (j = MAX_PILS-1; j > 0; j--) {
268                 if (pil_pending & (1 << j)) {
269                     if (!(s->slaves[i].irl_out & (1 << j))) {
270                         qemu_irq_raise(s->cpu_irqs[i][j]);
271                     }
272                 } else {
273                     if (s->slaves[i].irl_out & (1 << j)) {
274                         qemu_irq_lower(s->cpu_irqs[i][j]);
275                     }
276                 }
277             }
278         }
279         s->slaves[i].irl_out = pil_pending;
280     }
281 }
282 
283 /*
284  * "irq" here is the bit number in the system interrupt register to
285  * separate serial and keyboard interrupts sharing a level.
286  */
287 static void slavio_set_irq(void *opaque, int irq, int level)
288 {
289     SLAVIO_INTCTLState *s = opaque;
290     uint32_t mask = 1 << irq;
291     uint32_t pil = intbit_to_level[irq];
292     unsigned int i;
293 
294     trace_slavio_set_irq(s->target_cpu, irq, pil, level);
295     if (pil > 0) {
296         if (level) {
297 #ifdef DEBUG_IRQ_COUNT
298             s->irq_count[pil]++;
299 #endif
300             s->intregm_pending |= mask;
301             if (pil == 15) {
302                 for (i = 0; i < MAX_CPUS; i++) {
303                     s->slaves[i].intreg_pending |= 1 << pil;
304                 }
305             }
306         } else {
307             s->intregm_pending &= ~mask;
308             if (pil == 15) {
309                 for (i = 0; i < MAX_CPUS; i++) {
310                     s->slaves[i].intreg_pending &= ~(1 << pil);
311                 }
312             }
313         }
314         slavio_check_interrupts(s, 1);
315     }
316 }
317 
318 static void slavio_set_timer_irq_cpu(void *opaque, int cpu, int level)
319 {
320     SLAVIO_INTCTLState *s = opaque;
321 
322     trace_slavio_set_timer_irq_cpu(cpu, level);
323 
324     if (level) {
325         s->slaves[cpu].intreg_pending |= CPU_IRQ_TIMER_IN;
326     } else {
327         s->slaves[cpu].intreg_pending &= ~CPU_IRQ_TIMER_IN;
328     }
329 
330     slavio_check_interrupts(s, 1);
331 }
332 
333 static void slavio_set_irq_all(void *opaque, int irq, int level)
334 {
335     if (irq < 32) {
336         slavio_set_irq(opaque, irq, level);
337     } else {
338         slavio_set_timer_irq_cpu(opaque, irq - 32, level);
339     }
340 }
341 
342 static int vmstate_intctl_post_load(void *opaque, int version_id)
343 {
344     SLAVIO_INTCTLState *s = opaque;
345 
346     slavio_check_interrupts(s, 0);
347     return 0;
348 }
349 
350 static const VMStateDescription vmstate_intctl_cpu = {
351     .name ="slavio_intctl_cpu",
352     .version_id = 1,
353     .minimum_version_id = 1,
354     .fields = (VMStateField[]) {
355         VMSTATE_UINT32(intreg_pending, SLAVIO_CPUINTCTLState),
356         VMSTATE_END_OF_LIST()
357     }
358 };
359 
360 static const VMStateDescription vmstate_intctl = {
361     .name ="slavio_intctl",
362     .version_id = 1,
363     .minimum_version_id = 1,
364     .post_load = vmstate_intctl_post_load,
365     .fields = (VMStateField[]) {
366         VMSTATE_STRUCT_ARRAY(slaves, SLAVIO_INTCTLState, MAX_CPUS, 1,
367                              vmstate_intctl_cpu, SLAVIO_CPUINTCTLState),
368         VMSTATE_UINT32(intregm_pending, SLAVIO_INTCTLState),
369         VMSTATE_UINT32(intregm_disabled, SLAVIO_INTCTLState),
370         VMSTATE_UINT32(target_cpu, SLAVIO_INTCTLState),
371         VMSTATE_END_OF_LIST()
372     }
373 };
374 
375 static void slavio_intctl_reset(DeviceState *d)
376 {
377     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(d);
378     int i;
379 
380     for (i = 0; i < MAX_CPUS; i++) {
381         s->slaves[i].intreg_pending = 0;
382         s->slaves[i].irl_out = 0;
383     }
384     s->intregm_disabled = ~MASTER_IRQ_MASK;
385     s->intregm_pending = 0;
386     s->target_cpu = 0;
387     slavio_check_interrupts(s, 0);
388 }
389 
390 #ifdef DEBUG_IRQ_COUNT
391 static bool slavio_intctl_get_statistics(InterruptStatsProvider *obj,
392                                          uint64_t **irq_counts,
393                                          unsigned int *nb_irqs)
394 {
395     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(obj);
396     *irq_counts = s->irq_count;
397     *nb_irqs = ARRAY_SIZE(s->irq_count);
398     return true;
399 }
400 #endif
401 
402 static void slavio_intctl_print_info(InterruptStatsProvider *obj, Monitor *mon)
403 {
404     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(obj);
405     int i;
406 
407     for (i = 0; i < MAX_CPUS; i++) {
408         monitor_printf(mon, "per-cpu %d: pending 0x%08x\n", i,
409                        s->slaves[i].intreg_pending);
410     }
411     monitor_printf(mon, "master: pending 0x%08x, disabled 0x%08x\n",
412                    s->intregm_pending, s->intregm_disabled);
413 }
414 
415 static void slavio_intctl_init(Object *obj)
416 {
417     DeviceState *dev = DEVICE(obj);
418     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(obj);
419     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
420     unsigned int i, j;
421     char slave_name[45];
422 
423     qdev_init_gpio_in(dev, slavio_set_irq_all, 32 + MAX_CPUS);
424     memory_region_init_io(&s->iomem, obj, &slavio_intctlm_mem_ops, s,
425                           "master-interrupt-controller", INTCTLM_SIZE);
426     sysbus_init_mmio(sbd, &s->iomem);
427 
428     for (i = 0; i < MAX_CPUS; i++) {
429         snprintf(slave_name, sizeof(slave_name),
430                  "slave-interrupt-controller-%i", i);
431         for (j = 0; j < MAX_PILS; j++) {
432             sysbus_init_irq(sbd, &s->cpu_irqs[i][j]);
433         }
434         memory_region_init_io(&s->slaves[i].iomem, OBJECT(s),
435                               &slavio_intctl_mem_ops,
436                               &s->slaves[i], slave_name, INTCTL_SIZE);
437         sysbus_init_mmio(sbd, &s->slaves[i].iomem);
438         s->slaves[i].cpu = i;
439         s->slaves[i].master = s;
440     }
441 }
442 
443 static void slavio_intctl_class_init(ObjectClass *klass, void *data)
444 {
445     DeviceClass *dc = DEVICE_CLASS(klass);
446     InterruptStatsProviderClass *ic = INTERRUPT_STATS_PROVIDER_CLASS(klass);
447 
448     dc->reset = slavio_intctl_reset;
449     dc->vmsd = &vmstate_intctl;
450 #ifdef DEBUG_IRQ_COUNT
451     ic->get_statistics = slavio_intctl_get_statistics;
452 #endif
453     ic->print_info = slavio_intctl_print_info;
454 }
455 
456 static const TypeInfo slavio_intctl_info = {
457     .name          = TYPE_SLAVIO_INTCTL,
458     .parent        = TYPE_SYS_BUS_DEVICE,
459     .instance_size = sizeof(SLAVIO_INTCTLState),
460     .instance_init = slavio_intctl_init,
461     .class_init    = slavio_intctl_class_init,
462     .interfaces = (InterfaceInfo[]) {
463         { TYPE_INTERRUPT_STATS_PROVIDER },
464         { }
465     },
466 };
467 
468 static void slavio_intctl_register_types(void)
469 {
470     type_register_static(&slavio_intctl_info);
471 }
472 
473 type_init(slavio_intctl_register_types)
474