hw/pm_smbus.c

   1 /*
   2  * PC SMBus implementation
   3  * splitted from acpi.c
   4  *
   5  * Copyright (c) 2006 Fabrice Bellard
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License version 2 as published by the Free Software Foundation.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA  02110-1301 USA
  19  */
  20 #include "hw.h"
  21 #include "pc.h"
  22 #include "pm_smbus.h"
  23 #include "pci.h"
  24 #include "qemu-timer.h"
  25 #include "sysemu.h"
  26 #include "i2c.h"
  27 #include "smbus.h"
  28 #include "kvm.h"
  29
  30 /* no save/load? */
  31
  32 #define SMBHSTSTS       0x00
  33 #define SMBHSTCNT       0x02
  34 #define SMBHSTCMD       0x03
  35 #define SMBHSTADD       0x04
  36 #define SMBHSTDAT0      0x05
  37 #define SMBHSTDAT1      0x06
  38 #define SMBBLKDAT       0x07
  39
  40 static void smb_transaction(PMSMBus *s)
  41 {
  42     uint8_t prot = (s->smb_ctl >> 2) & 0x07;
  43     uint8_t read = s->smb_addr & 0x01;
  44     uint8_t cmd = s->smb_cmd;
  45     uint8_t addr = s->smb_addr >> 1;
  46     i2c_bus *bus = s->smbus;
  47
  48 #ifdef DEBUG
  49     printf("SMBus trans addr=0x%02x prot=0x%02x\n", addr, prot);
  50 #endif
  51     switch(prot) {
  52     case 0x0:
  53         smbus_quick_command(bus, addr, read);
  54         break;
  55     case 0x1:
  56         if (read) {
  57             s->smb_data0 = smbus_receive_byte(bus, addr);
  58         } else {
  59             smbus_send_byte(bus, addr, cmd);
  60         }
  61         break;
  62     case 0x2:
  63         if (read) {
  64             s->smb_data0 = smbus_read_byte(bus, addr, cmd);
  65         } else {
  66             smbus_write_byte(bus, addr, cmd, s->smb_data0);
  67         }
  68         break;
  69     case 0x3:
  70         if (read) {
  71             uint16_t val;
  72             val = smbus_read_word(bus, addr, cmd);
  73             s->smb_data0 = val;
  74             s->smb_data1 = val >> 8;
  75         } else {
  76             smbus_write_word(bus, addr, cmd, (s->smb_data1 << 8) | s->smb_data0);
  77         }
  78         break;
  79     case 0x5:
  80         if (read) {
  81             s->smb_data0 = smbus_read_block(bus, addr, cmd, s->smb_data);
  82         } else {
  83             smbus_write_block(bus, addr, cmd, s->smb_data, s->smb_data0);
  84         }
  85         break;
  86     default:
  87         goto error;
  88     }
  89     return;
  90
  91   error:
  92     s->smb_stat |= 0x04;
  93 }
  94
  95 void smb_ioport_writeb(void *opaque, uint32_t addr, uint32_t val)
  96 {
  97     PMSMBus *s = opaque;
  98     addr &= 0x3f;
  99 #ifdef DEBUG
 100     printf("SMB writeb port=0x%04x val=0x%02x\n", addr, val);
 101 #endif
 102     switch(addr) {
 103     case SMBHSTSTS:
 104         s->smb_stat = 0;
 105         s->smb_index = 0;
 106         break;
 107     case SMBHSTCNT:
 108         s->smb_ctl = val;
 109         if (val & 0x40)
 110             smb_transaction(s);
 111         break;
 112     case SMBHSTCMD:
 113         s->smb_cmd = val;
 114         break;
 115     case SMBHSTADD:
 116         s->smb_addr = val;
 117         break;
 118     case SMBHSTDAT0:
 119         s->smb_data0 = val;
 120         break;
 121     case SMBHSTDAT1:
 122         s->smb_data1 = val;
 123         break;
 124     case SMBBLKDAT:
 125         s->smb_data[s->smb_index++] = val;
 126         if (s->smb_index > 31)
 127             s->smb_index = 0;
 128         break;
 129     default:
 130         break;
 131     }
 132 }
 133
 134 uint32_t smb_ioport_readb(void *opaque, uint32_t addr)
 135 {
 136     PMSMBus *s = opaque;
 137     uint32_t val;
 138
 139     addr &= 0x3f;
 140     switch(addr) {
 141     case SMBHSTSTS:
 142         val = s->smb_stat;
 143         break;
 144     case SMBHSTCNT:
 145         s->smb_index = 0;
 146         val = s->smb_ctl & 0x1f;
 147         break;
 148     case SMBHSTCMD:
 149         val = s->smb_cmd;
 150         break;
 151     case SMBHSTADD:
 152         val = s->smb_addr;
 153         break;
 154     case SMBHSTDAT0:
 155         val = s->smb_data0;
 156         break;
 157     case SMBHSTDAT1:
 158         val = s->smb_data1;
 159         break;
 160     case SMBBLKDAT:
 161         val = s->smb_data[s->smb_index++];
 162         if (s->smb_index > 31)
 163             s->smb_index = 0;
 164         break;
 165     default:
 166         val = 0;
 167         break;
 168     }
 169 #ifdef DEBUG
 170     printf("SMB readb port=0x%04x val=0x%02x\n", addr, val);
 171 #endif
 172     return val;
 173 }
 174
 175 void pm_smbus_init(DeviceState *parent, PMSMBus *smb)
 176 {
 177     smb->smbus = i2c_init_bus(parent, "i2c");
 178 }