xref: /openbmc/qemu/hw/intc/slavio_intctl.c (revision 56983463)
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 typedef struct SLAVIO_INTCTLState {
57     SysBusDevice busdev;
58     MemoryRegion iomem;
59 #ifdef DEBUG_IRQ_COUNT
60     uint64_t irq_count[32];
61 #endif
62     qemu_irq cpu_irqs[MAX_CPUS][MAX_PILS];
63     SLAVIO_CPUINTCTLState slaves[MAX_CPUS];
64     uint32_t intregm_pending;
65     uint32_t intregm_disabled;
66     uint32_t target_cpu;
67 } SLAVIO_INTCTLState;
68 
69 #define INTCTL_MAXADDR 0xf
70 #define INTCTL_SIZE (INTCTL_MAXADDR + 1)
71 #define INTCTLM_SIZE 0x14
72 #define MASTER_IRQ_MASK ~0x0fa2007f
73 #define MASTER_DISABLE 0x80000000
74 #define CPU_SOFTIRQ_MASK 0xfffe0000
75 #define CPU_IRQ_INT15_IN (1 << 15)
76 #define CPU_IRQ_TIMER_IN (1 << 14)
77 
78 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs);
79 
80 // per-cpu interrupt controller
81 static uint64_t slavio_intctl_mem_readl(void *opaque, hwaddr addr,
82                                         unsigned size)
83 {
84     SLAVIO_CPUINTCTLState *s = opaque;
85     uint32_t saddr, ret;
86 
87     saddr = addr >> 2;
88     switch (saddr) {
89     case 0:
90         ret = s->intreg_pending;
91         break;
92     default:
93         ret = 0;
94         break;
95     }
96     trace_slavio_intctl_mem_readl(s->cpu, addr, ret);
97 
98     return ret;
99 }
100 
101 static void slavio_intctl_mem_writel(void *opaque, hwaddr addr,
102                                      uint64_t val, unsigned size)
103 {
104     SLAVIO_CPUINTCTLState *s = opaque;
105     uint32_t saddr;
106 
107     saddr = addr >> 2;
108     trace_slavio_intctl_mem_writel(s->cpu, addr, val);
109     switch (saddr) {
110     case 1: // clear pending softints
111         val &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN;
112         s->intreg_pending &= ~val;
113         slavio_check_interrupts(s->master, 1);
114         trace_slavio_intctl_mem_writel_clear(s->cpu, val, s->intreg_pending);
115         break;
116     case 2: // set softint
117         val &= CPU_SOFTIRQ_MASK;
118         s->intreg_pending |= val;
119         slavio_check_interrupts(s->master, 1);
120         trace_slavio_intctl_mem_writel_set(s->cpu, val, s->intreg_pending);
121         break;
122     default:
123         break;
124     }
125 }
126 
127 static const MemoryRegionOps slavio_intctl_mem_ops = {
128     .read = slavio_intctl_mem_readl,
129     .write = slavio_intctl_mem_writel,
130     .endianness = DEVICE_NATIVE_ENDIAN,
131     .valid = {
132         .min_access_size = 4,
133         .max_access_size = 4,
134     },
135 };
136 
137 // master system interrupt controller
138 static uint64_t slavio_intctlm_mem_readl(void *opaque, hwaddr addr,
139                                          unsigned size)
140 {
141     SLAVIO_INTCTLState *s = opaque;
142     uint32_t saddr, ret;
143 
144     saddr = addr >> 2;
145     switch (saddr) {
146     case 0:
147         ret = s->intregm_pending & ~MASTER_DISABLE;
148         break;
149     case 1:
150         ret = s->intregm_disabled & MASTER_IRQ_MASK;
151         break;
152     case 4:
153         ret = s->target_cpu;
154         break;
155     default:
156         ret = 0;
157         break;
158     }
159     trace_slavio_intctlm_mem_readl(addr, ret);
160 
161     return ret;
162 }
163 
164 static void slavio_intctlm_mem_writel(void *opaque, hwaddr addr,
165                                       uint64_t val, unsigned size)
166 {
167     SLAVIO_INTCTLState *s = opaque;
168     uint32_t saddr;
169 
170     saddr = addr >> 2;
171     trace_slavio_intctlm_mem_writel(addr, val);
172     switch (saddr) {
173     case 2: // clear (enable)
174         // Force clear unused bits
175         val &= MASTER_IRQ_MASK;
176         s->intregm_disabled &= ~val;
177         trace_slavio_intctlm_mem_writel_enable(val, s->intregm_disabled);
178         slavio_check_interrupts(s, 1);
179         break;
180     case 3: // set (disable; doesn't affect pending)
181         // Force clear unused bits
182         val &= MASTER_IRQ_MASK;
183         s->intregm_disabled |= val;
184         slavio_check_interrupts(s, 1);
185         trace_slavio_intctlm_mem_writel_disable(val, s->intregm_disabled);
186         break;
187     case 4:
188         s->target_cpu = val & (MAX_CPUS - 1);
189         slavio_check_interrupts(s, 1);
190         trace_slavio_intctlm_mem_writel_target(s->target_cpu);
191         break;
192     default:
193         break;
194     }
195 }
196 
197 static const MemoryRegionOps slavio_intctlm_mem_ops = {
198     .read = slavio_intctlm_mem_readl,
199     .write = slavio_intctlm_mem_writel,
200     .endianness = DEVICE_NATIVE_ENDIAN,
201     .valid = {
202         .min_access_size = 4,
203         .max_access_size = 4,
204     },
205 };
206 
207 void slavio_pic_info(Monitor *mon, DeviceState *dev)
208 {
209     SysBusDevice *sd;
210     SLAVIO_INTCTLState *s;
211     int i;
212 
213     sd = SYS_BUS_DEVICE(dev);
214     s = FROM_SYSBUS(SLAVIO_INTCTLState, sd);
215     for (i = 0; i < MAX_CPUS; i++) {
216         monitor_printf(mon, "per-cpu %d: pending 0x%08x\n", i,
217                        s->slaves[i].intreg_pending);
218     }
219     monitor_printf(mon, "master: pending 0x%08x, disabled 0x%08x\n",
220                    s->intregm_pending, s->intregm_disabled);
221 }
222 
223 void slavio_irq_info(Monitor *mon, DeviceState *dev)
224 {
225 #ifndef DEBUG_IRQ_COUNT
226     monitor_printf(mon, "irq statistic code not compiled.\n");
227 #else
228     SysBusDevice *sd;
229     SLAVIO_INTCTLState *s;
230     int i;
231     int64_t count;
232 
233     sd = SYS_BUS_DEVICE(dev);
234     s = FROM_SYSBUS(SLAVIO_INTCTLState, sd);
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 & (1 << 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 = container_of(d, SLAVIO_INTCTLState, busdev.qdev);
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 *dev)
423 {
424     SLAVIO_INTCTLState *s = FROM_SYSBUS(SLAVIO_INTCTLState, dev);
425     unsigned int i, j;
426     char slave_name[45];
427 
428     qdev_init_gpio_in(&dev->qdev, 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(dev, &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(dev, &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(dev, &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          = "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