hw/char/debugcon.c

   1 /*
   2  * QEMU Bochs-style debug console ("port E9") emulation
   3  *
   4  * Copyright (c) 2003-2004 Fabrice Bellard
   5  * Copyright (c) 2008 Citrix Systems, Inc.
   6  * Copyright (c) Intel Corporation; author: H. Peter Anvin
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  24  * THE SOFTWARE.
  25  */
  26
  27 #include "hw/hw.h"
  28 #include "sysemu/char.h"
  29 #include "hw/isa/isa.h"
  30 #include "hw/i386/pc.h"
  31
  32 #define TYPE_ISA_DEBUGCON_DEVICE "isa-debugcon"
  33 #define ISA_DEBUGCON_DEVICE(obj) \
  34      OBJECT_CHECK(ISADebugconState, (obj), TYPE_ISA_DEBUGCON_DEVICE)
  35
  36 //#define DEBUG_DEBUGCON
  37
  38 typedef struct DebugconState {
  39     MemoryRegion io;
  40     CharDriverState *chr;
  41     uint32_t readback;
  42 } DebugconState;
  43
  44 typedef struct ISADebugconState {
  45     ISADevice parent_obj;
  46
  47     uint32_t iobase;
  48     DebugconState state;
  49 } ISADebugconState;
  50
  51 static void debugcon_ioport_write(void *opaque, hwaddr addr, uint64_t val,
  52                                   unsigned width)
  53 {
  54     DebugconState *s = opaque;
  55     unsigned char ch = val;
  56
  57 #ifdef DEBUG_DEBUGCON
  58     printf(" [debugcon: write addr=0x%04" HWADDR_PRIx " val=0x%02" PRIx64 "]\n", addr, val);
  59 #endif
  60
  61     qemu_chr_fe_write(s->chr, &ch, 1);
  62 }
  63
  64
  65 static uint64_t debugcon_ioport_read(void *opaque, hwaddr addr, unsigned width)
  66 {
  67     DebugconState *s = opaque;
  68
  69 #ifdef DEBUG_DEBUGCON
  70     printf("debugcon: read addr=0x%04" HWADDR_PRIx "\n", addr);
  71 #endif
  72
  73     return s->readback;
  74 }
  75
  76 static const MemoryRegionOps debugcon_ops = {
  77     .read = debugcon_ioport_read,
  78     .write = debugcon_ioport_write,
  79     .valid.min_access_size = 1,
  80     .valid.max_access_size = 1,
  81     .endianness = DEVICE_LITTLE_ENDIAN,
  82 };
  83
  84 static void debugcon_realize_core(DebugconState *s, Error **errp)
  85 {
  86     if (!s->chr) {
  87         error_setg(errp, "Can't create debugcon device, empty char device");
  88         return;
  89     }
  90
  91     qemu_chr_add_handlers(s->chr, NULL, NULL, NULL, s);
  92 }
  93
  94 static void debugcon_isa_realizefn(DeviceState *dev, Error **errp)
  95 {
  96     ISADevice *d = ISA_DEVICE(dev);
  97     ISADebugconState *isa = ISA_DEBUGCON_DEVICE(dev);
  98     DebugconState *s = &isa->state;
  99     Error *err = NULL;
 100
 101     debugcon_realize_core(s, &err);
 102     if (err != NULL) {
 103         error_propagate(errp, err);
 104         return;
 105     }
 106     memory_region_init_io(&s->io, &debugcon_ops, s,
 107                           TYPE_ISA_DEBUGCON_DEVICE, 1);
 108     memory_region_add_subregion(isa_address_space_io(d),
 109                                 isa->iobase, &s->io);
 110 }
 111
 112 static Property debugcon_isa_properties[] = {
 113     DEFINE_PROP_HEX32("iobase", ISADebugconState, iobase, 0xe9),
 114     DEFINE_PROP_CHR("chardev",  ISADebugconState, state.chr),
 115     DEFINE_PROP_HEX32("readback", ISADebugconState, state.readback, 0xe9),
 116     DEFINE_PROP_END_OF_LIST(),
 117 };
 118
 119 static void debugcon_isa_class_initfn(ObjectClass *klass, void *data)
 120 {
 121     DeviceClass *dc = DEVICE_CLASS(klass);
 122
 123     dc->realize = debugcon_isa_realizefn;
 124     dc->props = debugcon_isa_properties;
 125 }
 126
 127 static const TypeInfo debugcon_isa_info = {
 128     .name          = TYPE_ISA_DEBUGCON_DEVICE,
 129     .parent        = TYPE_ISA_DEVICE,
 130     .instance_size = sizeof(ISADebugconState),
 131     .class_init    = debugcon_isa_class_initfn,
 132 };
 133
 134 static void debugcon_register_types(void)
 135 {
 136     type_register_static(&debugcon_isa_info);
 137 }
 138
 139 type_init(debugcon_register_types)