hw/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.h"
  28 #include "qemu-char.h"
  29 #include "isa.h"
  30 #include "pc.h"
  31
  32 //#define DEBUG_DEBUGCON
  33
  34 typedef struct DebugconState {
  35     CharDriverState *chr;
  36     uint32_t readback;
  37 } DebugconState;
  38
  39 typedef struct ISADebugconState {
  40     ISADevice dev;
  41     uint32_t iobase;
  42     DebugconState state;
  43 } ISADebugconState;
  44
  45 static void debugcon_ioport_write(void *opaque, uint32_t addr, uint32_t val)
  46 {
  47     DebugconState *s = opaque;
  48     unsigned char ch = val;
  49
  50 #ifdef DEBUG_DEBUGCON
  51     printf("debugcon: write addr=0x%04x val=0x%02x\n", addr, val);
  52 #endif
  53
  54     qemu_chr_fe_write(s->chr, &ch, 1);
  55 }
  56
  57
  58 static uint32_t debugcon_ioport_read(void *opaque, uint32_t addr)
  59 {
  60     DebugconState *s = opaque;
  61
  62 #ifdef DEBUG_DEBUGCON
  63     printf("debugcon: read addr=0x%04x\n", addr);
  64 #endif
  65
  66     return s->readback;
  67 }
  68
  69 static void debugcon_init_core(DebugconState *s)
  70 {
  71     if (!s->chr) {
  72         fprintf(stderr, "Can't create debugcon device, empty char device\n");
  73         exit(1);
  74     }
  75
  76     qemu_chr_add_handlers(s->chr, NULL, NULL, NULL, s);
  77 }
  78
  79 static int debugcon_isa_initfn(ISADevice *dev)
  80 {
  81     ISADebugconState *isa = DO_UPCAST(ISADebugconState, dev, dev);
  82     DebugconState *s = &isa->state;
  83
  84     debugcon_init_core(s);
  85     register_ioport_write(isa->iobase, 1, 1, debugcon_ioport_write, s);
  86     register_ioport_read(isa->iobase, 1, 1, debugcon_ioport_read, s);
  87     return 0;
  88 }
  89
  90 static ISADeviceInfo debugcon_isa_info = {
  91     .qdev.name  = "isa-debugcon",
  92     .qdev.size  = sizeof(ISADebugconState),
  93     .init       = debugcon_isa_initfn,
  94     .qdev.props = (Property[]) {
  95         DEFINE_PROP_HEX32("iobase", ISADebugconState, iobase, 0xe9),
  96         DEFINE_PROP_CHR("chardev",  ISADebugconState, state.chr),
  97         DEFINE_PROP_HEX32("readback", ISADebugconState, state.readback, 0xe9),
  98         DEFINE_PROP_END_OF_LIST(),
  99     },
 100 };
 101
 102 static void debugcon_register_devices(void)
 103 {
 104     isa_qdev_register(&debugcon_isa_info);
 105 }
 106
 107 device_init(debugcon_register_devices)