xref: /openbmc/qemu/hw/intc/slavio_intctl.c (revision 4a66d3bf)
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 "hw/sparc/sun4m.h"
26 #include "monitor/monitor.h"
27 #include "hw/sysbus.h"
28 #include "trace.h"
29 
30 //#define DEBUG_IRQ_COUNT
31 
32 /*
33  * Registers of interrupt controller in sun4m.
34  *
35  * This is the interrupt controller part of chip STP2001 (Slave I/O), also
36  * produced as NCR89C105. See
37  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C105.txt
38  *
39  * There is a system master controller and one for each cpu.
40  *
41  */
42 
43 #define MAX_CPUS 16
44 #define MAX_PILS 16
45 
46 struct SLAVIO_INTCTLState;
47 
48 typedef struct SLAVIO_CPUINTCTLState {
49     MemoryRegion iomem;
50     struct SLAVIO_INTCTLState *master;
51     uint32_t intreg_pending;
52     uint32_t cpu;
53     uint32_t irl_out;
54 } SLAVIO_CPUINTCTLState;
55 
56 #define TYPE_SLAVIO_INTCTL "slavio_intctl"
57 #define SLAVIO_INTCTL(obj) \
58     OBJECT_CHECK(SLAVIO_INTCTLState, (obj), TYPE_SLAVIO_INTCTL)
59 
60 typedef struct SLAVIO_INTCTLState {
61     SysBusDevice parent_obj;
62 
63     MemoryRegion iomem;
64 #ifdef DEBUG_IRQ_COUNT
65     uint64_t irq_count[32];
66 #endif
67     qemu_irq cpu_irqs[MAX_CPUS][MAX_PILS];
68     SLAVIO_CPUINTCTLState slaves[MAX_CPUS];
69     uint32_t intregm_pending;
70     uint32_t intregm_disabled;
71     uint32_t target_cpu;
72 } SLAVIO_INTCTLState;
73 
74 #define INTCTL_MAXADDR 0xf
75 #define INTCTL_SIZE (INTCTL_MAXADDR + 1)
76 #define INTCTLM_SIZE 0x14
77 #define MASTER_IRQ_MASK ~0x0fa2007f
78 #define MASTER_DISABLE 0x80000000
79 #define CPU_SOFTIRQ_MASK 0xfffe0000
80 #define CPU_IRQ_INT15_IN (1 << 15)
81 #define CPU_IRQ_TIMER_IN (1 << 14)
82 
83 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs);
84 
85 // per-cpu interrupt controller
86 static uint64_t slavio_intctl_mem_readl(void *opaque, hwaddr addr,
87                                         unsigned size)
88 {
89     SLAVIO_CPUINTCTLState *s = opaque;
90     uint32_t saddr, ret;
91 
92     saddr = addr >> 2;
93     switch (saddr) {
94     case 0:
95         ret = s->intreg_pending;
96         break;
97     default:
98         ret = 0;
99         break;
100     }
101     trace_slavio_intctl_mem_readl(s->cpu, addr, ret);
102 
103     return ret;
104 }
105 
106 static void slavio_intctl_mem_writel(void *opaque, hwaddr addr,
107                                      uint64_t val, unsigned size)
108 {
109     SLAVIO_CPUINTCTLState *s = opaque;
110     uint32_t saddr;
111 
112     saddr = addr >> 2;
113     trace_slavio_intctl_mem_writel(s->cpu, addr, val);
114     switch (saddr) {
115     case 1: // clear pending softints
116         val &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN;
117         s->intreg_pending &= ~val;
118         slavio_check_interrupts(s->master, 1);
119         trace_slavio_intctl_mem_writel_clear(s->cpu, val, s->intreg_pending);
120         break;
121     case 2: // set softint
122         val &= CPU_SOFTIRQ_MASK;
123         s->intreg_pending |= val;
124         slavio_check_interrupts(s->master, 1);
125         trace_slavio_intctl_mem_writel_set(s->cpu, val, s->intreg_pending);
126         break;
127     default:
128         break;
129     }
130 }
131 
132 static const MemoryRegionOps slavio_intctl_mem_ops = {
133     .read = slavio_intctl_mem_readl,
134     .write = slavio_intctl_mem_writel,
135     .endianness = DEVICE_NATIVE_ENDIAN,
136     .valid = {
137         .min_access_size = 4,
138         .max_access_size = 4,
139     },
140 };
141 
142 // master system interrupt controller
143 static uint64_t slavio_intctlm_mem_readl(void *opaque, hwaddr addr,
144                                          unsigned size)
145 {
146     SLAVIO_INTCTLState *s = opaque;
147     uint32_t saddr, ret;
148 
149     saddr = addr >> 2;
150     switch (saddr) {
151     case 0:
152         ret = s->intregm_pending & ~MASTER_DISABLE;
153         break;
154     case 1:
155         ret = s->intregm_disabled & MASTER_IRQ_MASK;
156         break;
157     case 4:
158         ret = s->target_cpu;
159         break;
160     default:
161         ret = 0;
162         break;
163     }
164     trace_slavio_intctlm_mem_readl(addr, ret);
165 
166     return ret;
167 }
168 
169 static void slavio_intctlm_mem_writel(void *opaque, hwaddr addr,
170                                       uint64_t val, unsigned size)
171 {
172     SLAVIO_INTCTLState *s = opaque;
173     uint32_t saddr;
174 
175     saddr = addr >> 2;
176     trace_slavio_intctlm_mem_writel(addr, val);
177     switch (saddr) {
178     case 2: // clear (enable)
179         // Force clear unused bits
180         val &= MASTER_IRQ_MASK;
181         s->intregm_disabled &= ~val;
182         trace_slavio_intctlm_mem_writel_enable(val, s->intregm_disabled);
183         slavio_check_interrupts(s, 1);
184         break;
185     case 3: // set (disable; doesn't affect pending)
186         // Force clear unused bits
187         val &= MASTER_IRQ_MASK;
188         s->intregm_disabled |= val;
189         slavio_check_interrupts(s, 1);
190         trace_slavio_intctlm_mem_writel_disable(val, s->intregm_disabled);
191         break;
192     case 4:
193         s->target_cpu = val & (MAX_CPUS - 1);
194         slavio_check_interrupts(s, 1);
195         trace_slavio_intctlm_mem_writel_target(s->target_cpu);
196         break;
197     default:
198         break;
199     }
200 }
201 
202 static const MemoryRegionOps slavio_intctlm_mem_ops = {
203     .read = slavio_intctlm_mem_readl,
204     .write = slavio_intctlm_mem_writel,
205     .endianness = DEVICE_NATIVE_ENDIAN,
206     .valid = {
207         .min_access_size = 4,
208         .max_access_size = 4,
209     },
210 };
211 
212 void slavio_pic_info(Monitor *mon, DeviceState *dev)
213 {
214     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(dev);
215     int i;
216 
217     for (i = 0; i < MAX_CPUS; i++) {
218         monitor_printf(mon, "per-cpu %d: pending 0x%08x\n", i,
219                        s->slaves[i].intreg_pending);
220     }
221     monitor_printf(mon, "master: pending 0x%08x, disabled 0x%08x\n",
222                    s->intregm_pending, s->intregm_disabled);
223 }
224 
225 void slavio_irq_info(Monitor *mon, DeviceState *dev)
226 {
227 #ifndef DEBUG_IRQ_COUNT
228     monitor_printf(mon, "irq statistic code not compiled.\n");
229 #else
230     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(dev);
231     int i;
232     int64_t count;
233 
234     s = SLAVIO_INTCTL(dev);
235     monitor_printf(mon, "IRQ statistics:\n");
236     for (i = 0; i < 32; i++) {
237         count = s->irq_count[i];
238         if (count > 0)
239             monitor_printf(mon, "%2d: %" PRId64 "\n", i, count);
240     }
241 #endif
242 }
243 
244 static const uint32_t intbit_to_level[] = {
245     2, 3, 5, 7, 9, 11, 13, 2,   3, 5, 7, 9, 11, 13, 12, 12,
246     6, 13, 4, 10, 8, 9, 11, 0,  0, 0, 0, 15, 15, 15, 15, 0,
247 };
248 
249 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs)
250 {
251     uint32_t pending = s->intregm_pending, pil_pending;
252     unsigned int i, j;
253 
254     pending &= ~s->intregm_disabled;
255 
256     trace_slavio_check_interrupts(pending, s->intregm_disabled);
257     for (i = 0; i < MAX_CPUS; i++) {
258         pil_pending = 0;
259 
260         /* If we are the current interrupt target, get hard interrupts */
261         if (pending && !(s->intregm_disabled & MASTER_DISABLE) &&
262             (i == s->target_cpu)) {
263             for (j = 0; j < 32; j++) {
264                 if ((pending & (1 << j)) && intbit_to_level[j]) {
265                     pil_pending |= 1 << intbit_to_level[j];
266                 }
267             }
268         }
269 
270         /* Calculate current pending hard interrupts for display */
271         s->slaves[i].intreg_pending &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN |
272             CPU_IRQ_TIMER_IN;
273         if (i == s->target_cpu) {
274             for (j = 0; j < 32; j++) {
275                 if ((s->intregm_pending & (1U << j)) && intbit_to_level[j]) {
276                     s->slaves[i].intreg_pending |= 1 << intbit_to_level[j];
277                 }
278             }
279         }
280 
281         /* Level 15 and CPU timer interrupts are only masked when
282            the MASTER_DISABLE bit is set */
283         if (!(s->intregm_disabled & MASTER_DISABLE)) {
284             pil_pending |= s->slaves[i].intreg_pending &
285                 (CPU_IRQ_INT15_IN | CPU_IRQ_TIMER_IN);
286         }
287 
288         /* Add soft interrupts */
289         pil_pending |= (s->slaves[i].intreg_pending & CPU_SOFTIRQ_MASK) >> 16;
290 
291         if (set_irqs) {
292             /* Since there is not really an interrupt 0 (and pil_pending
293              * and irl_out bit zero are thus always zero) there is no need
294              * to do anything with cpu_irqs[i][0] and it is OK not to do
295              * the j=0 iteration of this loop.
296              */
297             for (j = MAX_PILS-1; j > 0; j--) {
298                 if (pil_pending & (1 << j)) {
299                     if (!(s->slaves[i].irl_out & (1 << j))) {
300                         qemu_irq_raise(s->cpu_irqs[i][j]);
301                     }
302                 } else {
303                     if (s->slaves[i].irl_out & (1 << j)) {
304                         qemu_irq_lower(s->cpu_irqs[i][j]);
305                     }
306                 }
307             }
308         }
309         s->slaves[i].irl_out = pil_pending;
310     }
311 }
312 
313 /*
314  * "irq" here is the bit number in the system interrupt register to
315  * separate serial and keyboard interrupts sharing a level.
316  */
317 static void slavio_set_irq(void *opaque, int irq, int level)
318 {
319     SLAVIO_INTCTLState *s = opaque;
320     uint32_t mask = 1 << irq;
321     uint32_t pil = intbit_to_level[irq];
322     unsigned int i;
323 
324     trace_slavio_set_irq(s->target_cpu, irq, pil, level);
325     if (pil > 0) {
326         if (level) {
327 #ifdef DEBUG_IRQ_COUNT
328             s->irq_count[pil]++;
329 #endif
330             s->intregm_pending |= mask;
331             if (pil == 15) {
332                 for (i = 0; i < MAX_CPUS; i++) {
333                     s->slaves[i].intreg_pending |= 1 << pil;
334                 }
335             }
336         } else {
337             s->intregm_pending &= ~mask;
338             if (pil == 15) {
339                 for (i = 0; i < MAX_CPUS; i++) {
340                     s->slaves[i].intreg_pending &= ~(1 << pil);
341                 }
342             }
343         }
344         slavio_check_interrupts(s, 1);
345     }
346 }
347 
348 static void slavio_set_timer_irq_cpu(void *opaque, int cpu, int level)
349 {
350     SLAVIO_INTCTLState *s = opaque;
351 
352     trace_slavio_set_timer_irq_cpu(cpu, level);
353 
354     if (level) {
355         s->slaves[cpu].intreg_pending |= CPU_IRQ_TIMER_IN;
356     } else {
357         s->slaves[cpu].intreg_pending &= ~CPU_IRQ_TIMER_IN;
358     }
359 
360     slavio_check_interrupts(s, 1);
361 }
362 
363 static void slavio_set_irq_all(void *opaque, int irq, int level)
364 {
365     if (irq < 32) {
366         slavio_set_irq(opaque, irq, level);
367     } else {
368         slavio_set_timer_irq_cpu(opaque, irq - 32, level);
369     }
370 }
371 
372 static int vmstate_intctl_post_load(void *opaque, int version_id)
373 {
374     SLAVIO_INTCTLState *s = opaque;
375 
376     slavio_check_interrupts(s, 0);
377     return 0;
378 }
379 
380 static const VMStateDescription vmstate_intctl_cpu = {
381     .name ="slavio_intctl_cpu",
382     .version_id = 1,
383     .minimum_version_id = 1,
384     .minimum_version_id_old = 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     .minimum_version_id_old = 1,
396     .post_load = vmstate_intctl_post_load,
397     .fields      = (VMStateField []) {
398         VMSTATE_STRUCT_ARRAY(slaves, SLAVIO_INTCTLState, MAX_CPUS, 1,
399                              vmstate_intctl_cpu, SLAVIO_CPUINTCTLState),
400         VMSTATE_UINT32(intregm_pending, SLAVIO_INTCTLState),
401         VMSTATE_UINT32(intregm_disabled, SLAVIO_INTCTLState),
402         VMSTATE_UINT32(target_cpu, SLAVIO_INTCTLState),
403         VMSTATE_END_OF_LIST()
404     }
405 };
406 
407 static void slavio_intctl_reset(DeviceState *d)
408 {
409     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(d);
410     int i;
411 
412     for (i = 0; i < MAX_CPUS; i++) {
413         s->slaves[i].intreg_pending = 0;
414         s->slaves[i].irl_out = 0;
415     }
416     s->intregm_disabled = ~MASTER_IRQ_MASK;
417     s->intregm_pending = 0;
418     s->target_cpu = 0;
419     slavio_check_interrupts(s, 0);
420 }
421 
422 static int slavio_intctl_init1(SysBusDevice *sbd)
423 {
424     DeviceState *dev = DEVICE(sbd);
425     SLAVIO_INTCTLState *s = SLAVIO_INTCTL(dev);
426     unsigned int i, j;
427     char slave_name[45];
428 
429     qdev_init_gpio_in(dev, slavio_set_irq_all, 32 + MAX_CPUS);
430     memory_region_init_io(&s->iomem, OBJECT(s), &slavio_intctlm_mem_ops, s,
431                           "master-interrupt-controller", INTCTLM_SIZE);
432     sysbus_init_mmio(sbd, &s->iomem);
433 
434     for (i = 0; i < MAX_CPUS; i++) {
435         snprintf(slave_name, sizeof(slave_name),
436                  "slave-interrupt-controller-%i", i);
437         for (j = 0; j < MAX_PILS; j++) {
438             sysbus_init_irq(sbd, &s->cpu_irqs[i][j]);
439         }
440         memory_region_init_io(&s->slaves[i].iomem, OBJECT(s),
441                               &slavio_intctl_mem_ops,
442                               &s->slaves[i], slave_name, INTCTL_SIZE);
443         sysbus_init_mmio(sbd, &s->slaves[i].iomem);
444         s->slaves[i].cpu = i;
445         s->slaves[i].master = s;
446     }
447 
448     return 0;
449 }
450 
451 static void slavio_intctl_class_init(ObjectClass *klass, void *data)
452 {
453     DeviceClass *dc = DEVICE_CLASS(klass);
454     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
455 
456     k->init = slavio_intctl_init1;
457     dc->reset = slavio_intctl_reset;
458     dc->vmsd = &vmstate_intctl;
459 }
460 
461 static const TypeInfo slavio_intctl_info = {
462     .name          = TYPE_SLAVIO_INTCTL,
463     .parent        = TYPE_SYS_BUS_DEVICE,
464     .instance_size = sizeof(SLAVIO_INTCTLState),
465     .class_init    = slavio_intctl_class_init,
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