xref: /openbmc/qemu/hw/intc/exynos4210_combiner.c (revision 9c4888c9)
1 /*
2  * Samsung exynos4210 Interrupt Combiner
3  *
4  * Copyright (c) 2000 - 2011 Samsung Electronics Co., Ltd.
5  * All rights reserved.
6  *
7  * Evgeny Voevodin <e.voevodin@samsung.com>
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License as published by the
11  * Free Software Foundation; either version 2 of the License, or (at your
12  * option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
17  * See the GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, see <http://www.gnu.org/licenses/>.
21  */
22 
23 /*
24  * Exynos4210 Combiner represents an OR gate for SOC's IRQ lines. It combines
25  * IRQ sources into groups and provides signal output to GIC from each group. It
26  * is driven by common mask and enable/disable logic. Take a note that not all
27  * IRQs are passed to GIC through Combiner.
28  */
29 
30 #include "qemu/osdep.h"
31 #include "hw/sysbus.h"
32 #include "migration/vmstate.h"
33 #include "qemu/module.h"
34 #include "hw/intc/exynos4210_combiner.h"
35 #include "hw/arm/exynos4210.h"
36 #include "hw/hw.h"
37 #include "hw/irq.h"
38 #include "hw/qdev-properties.h"
39 #include "qom/object.h"
40 
41 //#define DEBUG_COMBINER
42 
43 #ifdef DEBUG_COMBINER
44 #define DPRINTF(fmt, ...) \
45         do { fprintf(stdout, "COMBINER: [%s:%d] " fmt, __func__ , __LINE__, \
46                 ## __VA_ARGS__); } while (0)
47 #else
48 #define DPRINTF(fmt, ...) do {} while (0)
49 #endif
50 
51 #define IIC_REGION_SIZE    0x108         /* Size of memory mapped region */
52 
53 static const VMStateDescription vmstate_exynos4210_combiner_group_state = {
54     .name = "exynos4210.combiner.groupstate",
55     .version_id = 1,
56     .minimum_version_id = 1,
57     .fields = (VMStateField[]) {
58         VMSTATE_UINT8(src_mask, CombinerGroupState),
59         VMSTATE_UINT8(src_pending, CombinerGroupState),
60         VMSTATE_END_OF_LIST()
61     }
62 };
63 
64 static const VMStateDescription vmstate_exynos4210_combiner = {
65     .name = "exynos4210.combiner",
66     .version_id = 1,
67     .minimum_version_id = 1,
68     .fields = (VMStateField[]) {
69         VMSTATE_STRUCT_ARRAY(group, Exynos4210CombinerState, IIC_NGRP, 0,
70                 vmstate_exynos4210_combiner_group_state, CombinerGroupState),
71         VMSTATE_UINT32_ARRAY(reg_set, Exynos4210CombinerState,
72                 IIC_REGSET_SIZE),
73         VMSTATE_UINT32_ARRAY(icipsr, Exynos4210CombinerState, 2),
74         VMSTATE_UINT32(external, Exynos4210CombinerState),
75         VMSTATE_END_OF_LIST()
76     }
77 };
78 
79 static uint64_t
80 exynos4210_combiner_read(void *opaque, hwaddr offset, unsigned size)
81 {
82     struct Exynos4210CombinerState *s =
83             (struct Exynos4210CombinerState *)opaque;
84     uint32_t req_quad_base_n;    /* Base of registers quad. Multiply it by 4 and
85                                    get a start of corresponding group quad */
86     uint32_t grp_quad_base_n;    /* Base of group quad */
87     uint32_t reg_n;              /* Register number inside the quad */
88     uint32_t val;
89 
90     req_quad_base_n = offset >> 4;
91     grp_quad_base_n = req_quad_base_n << 2;
92     reg_n = (offset - (req_quad_base_n << 4)) >> 2;
93 
94     if (req_quad_base_n >= IIC_NGRP) {
95         /* Read of ICIPSR register */
96         return s->icipsr[reg_n];
97     }
98 
99     val = 0;
100 
101     switch (reg_n) {
102     /* IISTR */
103     case 2:
104         val |= s->group[grp_quad_base_n].src_pending;
105         val |= s->group[grp_quad_base_n + 1].src_pending << 8;
106         val |= s->group[grp_quad_base_n + 2].src_pending << 16;
107         val |= s->group[grp_quad_base_n + 3].src_pending << 24;
108         break;
109     /* IIMSR */
110     case 3:
111         val |= s->group[grp_quad_base_n].src_mask &
112         s->group[grp_quad_base_n].src_pending;
113         val |= (s->group[grp_quad_base_n + 1].src_mask &
114                 s->group[grp_quad_base_n + 1].src_pending) << 8;
115         val |= (s->group[grp_quad_base_n + 2].src_mask &
116                 s->group[grp_quad_base_n + 2].src_pending) << 16;
117         val |= (s->group[grp_quad_base_n + 3].src_mask &
118                 s->group[grp_quad_base_n + 3].src_pending) << 24;
119         break;
120     default:
121         if (offset >> 2 >= IIC_REGSET_SIZE) {
122             hw_error("exynos4210.combiner: overflow of reg_set by 0x"
123                     TARGET_FMT_plx "offset\n", offset);
124         }
125         val = s->reg_set[offset >> 2];
126     }
127     return val;
128 }
129 
130 static void exynos4210_combiner_update(void *opaque, uint8_t group_n)
131 {
132     struct Exynos4210CombinerState *s =
133             (struct Exynos4210CombinerState *)opaque;
134 
135     /* Send interrupt if needed */
136     if (s->group[group_n].src_mask & s->group[group_n].src_pending) {
137 #ifdef DEBUG_COMBINER
138         if (group_n != 26) {
139             /* skip uart */
140             DPRINTF("%s raise IRQ[%d]\n", s->external ? "EXT" : "INT", group_n);
141         }
142 #endif
143 
144         /* Set Combiner interrupt pending status after masking */
145         if (group_n >= 32) {
146             s->icipsr[1] |= 1 << (group_n - 32);
147         } else {
148             s->icipsr[0] |= 1 << group_n;
149         }
150 
151         qemu_irq_raise(s->output_irq[group_n]);
152     } else {
153 #ifdef DEBUG_COMBINER
154         if (group_n != 26) {
155             /* skip uart */
156             DPRINTF("%s lower IRQ[%d]\n", s->external ? "EXT" : "INT", group_n);
157         }
158 #endif
159 
160         /* Set Combiner interrupt pending status after masking */
161         if (group_n >= 32) {
162             s->icipsr[1] &= ~(1 << (group_n - 32));
163         } else {
164             s->icipsr[0] &= ~(1 << group_n);
165         }
166 
167         qemu_irq_lower(s->output_irq[group_n]);
168     }
169 }
170 
171 static void exynos4210_combiner_write(void *opaque, hwaddr offset,
172         uint64_t val, unsigned size)
173 {
174     struct Exynos4210CombinerState *s =
175             (struct Exynos4210CombinerState *)opaque;
176     uint32_t req_quad_base_n;    /* Base of registers quad. Multiply it by 4 and
177                                    get a start of corresponding group quad */
178     uint32_t grp_quad_base_n;    /* Base of group quad */
179     uint32_t reg_n;              /* Register number inside the quad */
180 
181     req_quad_base_n = offset >> 4;
182     grp_quad_base_n = req_quad_base_n << 2;
183     reg_n = (offset - (req_quad_base_n << 4)) >> 2;
184 
185     if (req_quad_base_n >= IIC_NGRP) {
186         hw_error("exynos4210.combiner: unallowed write access at offset 0x"
187                 TARGET_FMT_plx "\n", offset);
188         return;
189     }
190 
191     if (reg_n > 1) {
192         hw_error("exynos4210.combiner: unallowed write access at offset 0x"
193                 TARGET_FMT_plx "\n", offset);
194         return;
195     }
196 
197     if (offset >> 2 >= IIC_REGSET_SIZE) {
198         hw_error("exynos4210.combiner: overflow of reg_set by 0x"
199                 TARGET_FMT_plx "offset\n", offset);
200     }
201     s->reg_set[offset >> 2] = val;
202 
203     switch (reg_n) {
204     /* IIESR */
205     case 0:
206         /* FIXME: what if irq is pending, allowed by mask, and we allow it
207          * again. Interrupt will rise again! */
208 
209         DPRINTF("%s enable IRQ for groups %d, %d, %d, %d\n",
210                 s->external ? "EXT" : "INT",
211                 grp_quad_base_n,
212                 grp_quad_base_n + 1,
213                 grp_quad_base_n + 2,
214                 grp_quad_base_n + 3);
215 
216         /* Enable interrupt sources */
217         s->group[grp_quad_base_n].src_mask |= val & 0xFF;
218         s->group[grp_quad_base_n + 1].src_mask |= (val & 0xFF00) >> 8;
219         s->group[grp_quad_base_n + 2].src_mask |= (val & 0xFF0000) >> 16;
220         s->group[grp_quad_base_n + 3].src_mask |= (val & 0xFF000000) >> 24;
221 
222         exynos4210_combiner_update(s, grp_quad_base_n);
223         exynos4210_combiner_update(s, grp_quad_base_n + 1);
224         exynos4210_combiner_update(s, grp_quad_base_n + 2);
225         exynos4210_combiner_update(s, grp_quad_base_n + 3);
226         break;
227         /* IIECR */
228     case 1:
229         DPRINTF("%s disable IRQ for groups %d, %d, %d, %d\n",
230                 s->external ? "EXT" : "INT",
231                 grp_quad_base_n,
232                 grp_quad_base_n + 1,
233                 grp_quad_base_n + 2,
234                 grp_quad_base_n + 3);
235 
236         /* Disable interrupt sources */
237         s->group[grp_quad_base_n].src_mask &= ~(val & 0xFF);
238         s->group[grp_quad_base_n + 1].src_mask &= ~((val & 0xFF00) >> 8);
239         s->group[grp_quad_base_n + 2].src_mask &= ~((val & 0xFF0000) >> 16);
240         s->group[grp_quad_base_n + 3].src_mask &= ~((val & 0xFF000000) >> 24);
241 
242         exynos4210_combiner_update(s, grp_quad_base_n);
243         exynos4210_combiner_update(s, grp_quad_base_n + 1);
244         exynos4210_combiner_update(s, grp_quad_base_n + 2);
245         exynos4210_combiner_update(s, grp_quad_base_n + 3);
246         break;
247     default:
248         hw_error("exynos4210.combiner: unallowed write access at offset 0x"
249                 TARGET_FMT_plx "\n", offset);
250         break;
251     }
252 }
253 
254 /* Get combiner group and bit from irq number */
255 static uint8_t get_combiner_group_and_bit(int irq, uint8_t *bit)
256 {
257     *bit = irq - ((irq >> 3) << 3);
258     return irq >> 3;
259 }
260 
261 /* Process a change in an external IRQ input.  */
262 static void exynos4210_combiner_handler(void *opaque, int irq, int level)
263 {
264     struct Exynos4210CombinerState *s =
265             (struct Exynos4210CombinerState *)opaque;
266     uint8_t bit_n, group_n;
267 
268     group_n = get_combiner_group_and_bit(irq, &bit_n);
269 
270     if (s->external && group_n >= EXYNOS4210_MAX_EXT_COMBINER_OUT_IRQ) {
271         DPRINTF("%s unallowed IRQ group 0x%x\n", s->external ? "EXT" : "INT"
272                 , group_n);
273         return;
274     }
275 
276     if (level) {
277         s->group[group_n].src_pending |= 1 << bit_n;
278     } else {
279         s->group[group_n].src_pending &= ~(1 << bit_n);
280     }
281 
282     exynos4210_combiner_update(s, group_n);
283 }
284 
285 static void exynos4210_combiner_reset(DeviceState *d)
286 {
287     struct Exynos4210CombinerState *s = (struct Exynos4210CombinerState *)d;
288 
289     memset(&s->group, 0, sizeof(s->group));
290     memset(&s->reg_set, 0, sizeof(s->reg_set));
291 
292     s->reg_set[0xC0 >> 2] = 0x01010101;
293     s->reg_set[0xC4 >> 2] = 0x01010101;
294     s->reg_set[0xD0 >> 2] = 0x01010101;
295     s->reg_set[0xD4 >> 2] = 0x01010101;
296 }
297 
298 static const MemoryRegionOps exynos4210_combiner_ops = {
299     .read = exynos4210_combiner_read,
300     .write = exynos4210_combiner_write,
301     .endianness = DEVICE_NATIVE_ENDIAN,
302 };
303 
304 /*
305  * Internal Combiner initialization.
306  */
307 static void exynos4210_combiner_init(Object *obj)
308 {
309     DeviceState *dev = DEVICE(obj);
310     Exynos4210CombinerState *s = EXYNOS4210_COMBINER(obj);
311     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
312     unsigned int i;
313 
314     /* Allocate general purpose input signals and connect a handler to each of
315      * them */
316     qdev_init_gpio_in(dev, exynos4210_combiner_handler, IIC_NIRQ);
317 
318     /* Connect SysBusDev irqs to device specific irqs */
319     for (i = 0; i < IIC_NGRP; i++) {
320         sysbus_init_irq(sbd, &s->output_irq[i]);
321     }
322 
323     memory_region_init_io(&s->iomem, obj, &exynos4210_combiner_ops, s,
324                           "exynos4210-combiner", IIC_REGION_SIZE);
325     sysbus_init_mmio(sbd, &s->iomem);
326 }
327 
328 static Property exynos4210_combiner_properties[] = {
329     DEFINE_PROP_UINT32("external", Exynos4210CombinerState, external, 0),
330     DEFINE_PROP_END_OF_LIST(),
331 };
332 
333 static void exynos4210_combiner_class_init(ObjectClass *klass, void *data)
334 {
335     DeviceClass *dc = DEVICE_CLASS(klass);
336 
337     dc->reset = exynos4210_combiner_reset;
338     device_class_set_props(dc, exynos4210_combiner_properties);
339     dc->vmsd = &vmstate_exynos4210_combiner;
340 }
341 
342 static const TypeInfo exynos4210_combiner_info = {
343     .name          = TYPE_EXYNOS4210_COMBINER,
344     .parent        = TYPE_SYS_BUS_DEVICE,
345     .instance_size = sizeof(Exynos4210CombinerState),
346     .instance_init = exynos4210_combiner_init,
347     .class_init    = exynos4210_combiner_class_init,
348 };
349 
350 static void exynos4210_combiner_register_types(void)
351 {
352     type_register_static(&exynos4210_combiner_info);
353 }
354 
355 type_init(exynos4210_combiner_register_types)
356