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_DEBUG
  30
  31 #define VMPORT_CMD_GETVERSION 0x0a
  32 #define VMPORT_CMD_GETRAMSIZE 0x14
  33
  34 #define VMPORT_ENTRIES 0x2c
  35 #define VMPORT_MAGIC   0x564D5868
  36
  37 typedef struct _VMPortState
  38 {
  39     IOPortReadFunc *func[VMPORT_ENTRIES];
  40     void *opaque[VMPORT_ENTRIES];
  41 } VMPortState;
  42
  43 static VMPortState port_state;
  44
  45 void vmport_register(unsigned char command, IOPortReadFunc *func, void *opaque)
  46 {
  47     if (command >= VMPORT_ENTRIES)
  48         return;
  49
  50     port_state.func[command] = func;
  51     port_state.opaque[command] = opaque;
  52 }
  53
  54 static uint32_t vmport_ioport_read(void *opaque, uint32_t addr)
  55 {
  56     VMPortState *s = opaque;
  57     CPUState *env = cpu_single_env;
  58     unsigned char command;
  59     uint32_t eax;
  60
  61     eax = env->regs[R_EAX];
  62     if (eax != VMPORT_MAGIC)
  63         return eax;
  64
  65     command = env->regs[R_ECX];
  66     if (command >= VMPORT_ENTRIES)
  67         return eax;
  68     if (!s->func[command])
  69     {
  70 #ifdef VMPORT_DEBUG
  71         fprintf(stderr, "vmport: unknown command %x\n", command);
  72 #endif
  73         return eax;
  74     }
  75
  76     return s->func[command](s->opaque[command], addr);
  77 }
  78
  79 static void vmport_ioport_write(void *opaque, uint32_t addr, uint32_t val)
  80 {
  81     CPUState *env = cpu_single_env;
  82
  83     env->regs[R_EAX] = vmport_ioport_read(opaque, addr);
  84 }
  85
  86 static uint32_t vmport_cmd_get_version(void *opaque, uint32_t addr)
  87 {
  88     CPUState *env = cpu_single_env;
  89     env->regs[R_EBX] = VMPORT_MAGIC;
  90     return 6;
  91 }
  92
  93 static uint32_t vmport_cmd_ram_size(void *opaque, uint32_t addr)
  94 {
  95     CPUState *env = cpu_single_env;
  96     env->regs[R_EBX] = 0x1177;
  97     return ram_size;
  98 }
  99
 100 void vmport_init(void)
 101 {
 102     register_ioport_read(0x5658, 1, 4, vmport_ioport_read, &port_state);
 103     register_ioport_write(0x5658, 1, 4, vmport_ioport_write, &port_state);
 104
 105     /* Register some generic port commands */
 106     vmport_register(VMPORT_CMD_GETVERSION, vmport_cmd_get_version, NULL);
 107     vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, NULL);
 108 }