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 //#define DEBUG
  41
  42 #ifdef DEBUG
  43 # define SMBUS_DPRINTF(format, ...)     printf(format, ## __VA_ARGS__)
  44 #else
  45 # define SMBUS_DPRINTF(format, ...)     do { } while (0)
  46 #endif
  47
  48
  49 static void smb_transaction(PMSMBus *s)
  50 {
  51     uint8_t prot = (s->smb_ctl >> 2) & 0x07;
  52     uint8_t read = s->smb_addr & 0x01;
  53     uint8_t cmd = s->smb_cmd;
  54     uint8_t addr = s->smb_addr >> 1;
  55     i2c_bus *bus = s->smbus;
  56
  57     SMBUS_DPRINTF("SMBus trans addr=0x%02x prot=0x%02x\n", addr, prot);
  58     switch(prot) {
  59     case 0x0:
  60         smbus_quick_command(bus, addr, read);
  61         break;
  62     case 0x1:
  63         if (read) {
  64             s->smb_data0 = smbus_receive_byte(bus, addr);
  65         } else {
  66             smbus_send_byte(bus, addr, cmd);
  67         }
  68         break;
  69     case 0x2:
  70         if (read) {
  71             s->smb_data0 = smbus_read_byte(bus, addr, cmd);
  72         } else {
  73             smbus_write_byte(bus, addr, cmd, s->smb_data0);
  74         }
  75         break;
  76     case 0x3:
  77         if (read) {
  78             uint16_t val;
  79             val = smbus_read_word(bus, addr, cmd);
  80             s->smb_data0 = val;
  81             s->smb_data1 = val >> 8;
  82         } else {
  83             smbus_write_word(bus, addr, cmd, (s->smb_data1 << 8) | s->smb_data0);
  84         }
  85         break;
  86     case 0x5:
  87         if (read) {
  88             s->smb_data0 = smbus_read_block(bus, addr, cmd, s->smb_data);
  89         } else {
  90             smbus_write_block(bus, addr, cmd, s->smb_data, s->smb_data0);
  91         }
  92         break;
  93     default:
  94         goto error;
  95     }
  96     return;
  97
  98   error:
  99     s->smb_stat |= 0x04;
 100 }
 101
 102 void smb_ioport_writeb(void *opaque, uint32_t addr, uint32_t val)
 103 {
 104     PMSMBus *s = opaque;
 105     addr &= 0x3f;
 106     SMBUS_DPRINTF("SMB writeb port=0x%04x val=0x%02x\n", addr, val);
 107     switch(addr) {
 108     case SMBHSTSTS:
 109         s->smb_stat = 0;
 110         s->smb_index = 0;
 111         break;
 112     case SMBHSTCNT:
 113         s->smb_ctl = val;
 114         if (val & 0x40)
 115             smb_transaction(s);
 116         break;
 117     case SMBHSTCMD:
 118         s->smb_cmd = val;
 119         break;
 120     case SMBHSTADD:
 121         s->smb_addr = val;
 122         break;
 123     case SMBHSTDAT0:
 124         s->smb_data0 = val;
 125         break;
 126     case SMBHSTDAT1:
 127         s->smb_data1 = val;
 128         break;
 129     case SMBBLKDAT:
 130         s->smb_data[s->smb_index++] = val;
 131         if (s->smb_index > 31)
 132             s->smb_index = 0;
 133         break;
 134     default:
 135         break;
 136     }
 137 }
 138
 139 uint32_t smb_ioport_readb(void *opaque, uint32_t addr)
 140 {
 141     PMSMBus *s = opaque;
 142     uint32_t val;
 143
 144     addr &= 0x3f;
 145     switch(addr) {
 146     case SMBHSTSTS:
 147         val = s->smb_stat;
 148         break;
 149     case SMBHSTCNT:
 150         s->smb_index = 0;
 151         val = s->smb_ctl & 0x1f;
 152         break;
 153     case SMBHSTCMD:
 154         val = s->smb_cmd;
 155         break;
 156     case SMBHSTADD:
 157         val = s->smb_addr;
 158         break;
 159     case SMBHSTDAT0:
 160         val = s->smb_data0;
 161         break;
 162     case SMBHSTDAT1:
 163         val = s->smb_data1;
 164         break;
 165     case SMBBLKDAT:
 166         val = s->smb_data[s->smb_index++];
 167         if (s->smb_index > 31)
 168             s->smb_index = 0;
 169         break;
 170     default:
 171         val = 0;
 172         break;
 173     }
 174     SMBUS_DPRINTF("SMB readb port=0x%04x val=0x%02x\n", addr, val);
 175     return val;
 176 }
 177
 178 void pm_smbus_init(DeviceState *parent, PMSMBus *smb)
 179 {
 180     smb->smbus = i2c_init_bus(parent, "i2c");
 181 }