hw/vmport.c

   1 /*
   2  * QEMU VMPort emulation
   3  *
   4  * Copyright (C) 2007 Hervé Poussineau
   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 #include "hw.h"
  25 #include "isa.h"
  26 #include "pc.h"
  27 #include "sysemu.h"
  28
  29 #define VMPORT_CMD_GETVERSION 0x0a
  30 #define VMPORT_CMD_GETRAMSIZE 0x14
  31
  32 #define VMPORT_ENTRIES 0x2c
  33 #define VMPORT_MAGIC   0x564D5868
  34
  35 typedef struct _VMPortState
  36 {
  37     IOPortReadFunc *func[VMPORT_ENTRIES];
  38     void *opaque[VMPORT_ENTRIES];
  39 } VMPortState;
  40
  41 static VMPortState port_state;
  42
  43 void vmport_register(unsigned char command, IOPortReadFunc *func, void *opaque)
  44 {
  45     if (command >= VMPORT_ENTRIES)
  46         return;
  47
  48     port_state.func[command] = func;
  49     port_state.opaque[command] = opaque;
  50 }
  51
  52 static uint32_t vmport_ioport_read(void *opaque, uint32_t addr)
  53 {
  54     VMPortState *s = opaque;
  55     CPUState *env = cpu_single_env;
  56     unsigned char command;
  57     uint32_t eax;
  58
  59     eax = env->regs[R_EAX];
  60     if (eax != VMPORT_MAGIC)
  61         return eax;
  62
  63     command = env->regs[R_ECX];
  64     if (command >= VMPORT_ENTRIES)
  65         return eax;
  66     if (!s->func[command])
  67     {
  68         printf("vmport: unknown command %x\n", command);
  69         return eax;
  70     }
  71
  72     return s->func[command](s->opaque[command], addr);
  73 }
  74
  75 static uint32_t vmport_cmd_get_version(void *opaque, uint32_t addr)
  76 {
  77     CPUState *env = cpu_single_env;
  78     env->regs[R_EBX] = VMPORT_MAGIC;
  79     return 6;
  80 }
  81
  82 static uint32_t vmport_cmd_ram_size(void *opaque, uint32_t addr)
  83 {
  84     CPUState *env = cpu_single_env;
  85     env->regs[R_EBX] = 0x1177;
  86     return ram_size;
  87 }
  88
  89 void vmport_init(void)
  90 {
  91     register_ioport_read(0x5658, 1, 4, vmport_ioport_read, &port_state);
  92
  93     /* Register some generic port commands */
  94     vmport_register(VMPORT_CMD_GETVERSION, vmport_cmd_get_version, NULL);
  95     vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, NULL);
  96 }