xref: /qemu/hw/intc/xilinx_intc.c (revision f64766976d39fbf2b81a25b5c5f043180383d408)
1  /*
2   * QEMU Xilinx OPB Interrupt Controller.
3   *
4   * Copyright (c) 2009 Edgar E. Iglesias.
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/sysbus.h"
27  #include "qemu/module.h"
28  #include "hw/irq.h"
29  #include "hw/qdev-properties.h"
30  #include "qom/object.h"
31  
32  #define D(x)
33  
34  #define R_ISR       0
35  #define R_IPR       1
36  #define R_IER       2
37  #define R_IAR       3
38  #define R_SIE       4
39  #define R_CIE       5
40  #define R_IVR       6
41  #define R_MER       7
42  #define R_MAX       8
43  
44  #define TYPE_XILINX_INTC "xlnx.xps-intc"
45  DECLARE_INSTANCE_CHECKER(struct xlx_pic, XILINX_INTC,
46                           TYPE_XILINX_INTC)
47  
48  struct xlx_pic
49  {
50      SysBusDevice parent_obj;
51  
52      MemoryRegion mmio;
53      qemu_irq parent_irq;
54  
55      /* Configuration reg chosen at synthesis-time. QEMU populates
56         the bits at board-setup.  */
57      uint32_t c_kind_of_intr;
58  
59      /* Runtime control registers.  */
60      uint32_t regs[R_MAX];
61      /* state of the interrupt input pins */
62      uint32_t irq_pin_state;
63  };
64  
65  static void update_irq(struct xlx_pic *p)
66  {
67      uint32_t i;
68  
69      /* level triggered interrupt */
70      if (p->regs[R_MER] & 2) {
71          p->regs[R_ISR] |= p->irq_pin_state & ~p->c_kind_of_intr;
72      }
73  
74      /* Update the pending register.  */
75      p->regs[R_IPR] = p->regs[R_ISR] & p->regs[R_IER];
76  
77      /* Update the vector register.  */
78      for (i = 0; i < 32; i++) {
79          if (p->regs[R_IPR] & (1U << i)) {
80              break;
81          }
82      }
83      if (i == 32)
84          i = ~0;
85  
86      p->regs[R_IVR] = i;
87      qemu_set_irq(p->parent_irq, (p->regs[R_MER] & 1) && p->regs[R_IPR]);
88  }
89  
90  static uint64_t
91  pic_read(void *opaque, hwaddr addr, unsigned int size)
92  {
93      struct xlx_pic *p = opaque;
94      uint32_t r = 0;
95  
96      addr >>= 2;
97      switch (addr)
98      {
99          default:
100              if (addr < ARRAY_SIZE(p->regs))
101                  r = p->regs[addr];
102              break;
103  
104      }
105      D(printf("%s %x=%x\n", __func__, addr * 4, r));
106      return r;
107  }
108  
109  static void
110  pic_write(void *opaque, hwaddr addr,
111            uint64_t val64, unsigned int size)
112  {
113      struct xlx_pic *p = opaque;
114      uint32_t value = val64;
115  
116      addr >>= 2;
117      D(qemu_log("%s addr=%x val=%x\n", __func__, addr * 4, value));
118      switch (addr)
119      {
120          case R_IAR:
121              p->regs[R_ISR] &= ~value; /* ACK.  */
122              break;
123          case R_SIE:
124              p->regs[R_IER] |= value;  /* Atomic set ie.  */
125              break;
126          case R_CIE:
127              p->regs[R_IER] &= ~value; /* Atomic clear ie.  */
128              break;
129          case R_MER:
130              p->regs[R_MER] = value & 0x3;
131              break;
132          case R_ISR:
133              if ((p->regs[R_MER] & 2)) {
134                  break;
135              }
136              /* fallthrough */
137          default:
138              if (addr < ARRAY_SIZE(p->regs))
139                  p->regs[addr] = value;
140              break;
141      }
142      update_irq(p);
143  }
144  
145  static const MemoryRegionOps pic_ops = {
146      .read = pic_read,
147      .write = pic_write,
148      .endianness = DEVICE_NATIVE_ENDIAN,
149      .valid = {
150          .min_access_size = 4,
151          .max_access_size = 4
152      }
153  };
154  
155  static void irq_handler(void *opaque, int irq, int level)
156  {
157      struct xlx_pic *p = opaque;
158  
159      /* edge triggered interrupt */
160      if (p->c_kind_of_intr & (1 << irq) && p->regs[R_MER] & 2) {
161          p->regs[R_ISR] |= (level << irq);
162      }
163  
164      p->irq_pin_state &= ~(1 << irq);
165      p->irq_pin_state |= level << irq;
166      update_irq(p);
167  }
168  
169  static void xilinx_intc_init(Object *obj)
170  {
171      struct xlx_pic *p = XILINX_INTC(obj);
172  
173      qdev_init_gpio_in(DEVICE(obj), irq_handler, 32);
174      sysbus_init_irq(SYS_BUS_DEVICE(obj), &p->parent_irq);
175  
176      memory_region_init_io(&p->mmio, obj, &pic_ops, p, "xlnx.xps-intc",
177                            R_MAX * 4);
178      sysbus_init_mmio(SYS_BUS_DEVICE(obj), &p->mmio);
179  }
180  
181  static Property xilinx_intc_properties[] = {
182      DEFINE_PROP_UINT32("kind-of-intr", struct xlx_pic, c_kind_of_intr, 0),
183      DEFINE_PROP_END_OF_LIST(),
184  };
185  
186  static void xilinx_intc_class_init(ObjectClass *klass, void *data)
187  {
188      DeviceClass *dc = DEVICE_CLASS(klass);
189  
190      device_class_set_props(dc, xilinx_intc_properties);
191  }
192  
193  static const TypeInfo xilinx_intc_info = {
194      .name          = TYPE_XILINX_INTC,
195      .parent        = TYPE_SYS_BUS_DEVICE,
196      .instance_size = sizeof(struct xlx_pic),
197      .instance_init = xilinx_intc_init,
198      .class_init    = xilinx_intc_class_init,
199  };
200  
201  static void xilinx_intc_register_types(void)
202  {
203      type_register_static(&xilinx_intc_info);
204  }
205  
206  type_init(xilinx_intc_register_types)
207