Archipelago » qemu

/*

 * PC SMBus implementation

 * splitted from acpi.c

 *

 * Copyright (c) 2006 Fabrice Bellard

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License version 2 as published by the Free Software Foundation.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, see

 * <http://www.gnu.org/licenses/>.

 */

#include "hw/hw.h"

#include "hw/i386/pc.h"

#include "hw/i2c/pm_smbus.h"

#include "hw/i2c/smbus.h"

/* no save/load? */

#define SMBHSTSTS       0x00

#define SMBHSTCNT       0x02

#define SMBHSTCMD       0x03

#define SMBHSTADD       0x04

#define SMBHSTDAT0      0x05

#define SMBHSTDAT1      0x06

#define SMBBLKDAT       0x07

//#define DEBUG

#ifdef DEBUG

# define SMBUS_DPRINTF(format, ...)     printf(format, ## __VA_ARGS__)

#else

# define SMBUS_DPRINTF(format, ...)     do { } while (0)

#endif

static void smb_transaction(PMSMBus *s)

{

    uint8_t prot = (s->smb_ctl >> 2) & 0x07;

    uint8_t read = s->smb_addr & 0x01;

    uint8_t cmd = s->smb_cmd;

    uint8_t addr = s->smb_addr >> 1;

    i2c_bus *bus = s->smbus;

    SMBUS_DPRINTF("SMBus trans addr=0x%02x prot=0x%02x\n", addr, prot);

    switch(prot) {

    case 0x0:

        smbus_quick_command(bus, addr, read);

        break;

    case 0x1:

        if (read) {

            s->smb_data0 = smbus_receive_byte(bus, addr);

        } else {

            smbus_send_byte(bus, addr, cmd);

        }

        break;

    case 0x2:

        if (read) {

            s->smb_data0 = smbus_read_byte(bus, addr, cmd);

        } else {

            smbus_write_byte(bus, addr, cmd, s->smb_data0);

        }

        break;

    case 0x3:

        if (read) {

            uint16_t val;

            val = smbus_read_word(bus, addr, cmd);

            s->smb_data0 = val;

            s->smb_data1 = val >> 8;

        } else {

            smbus_write_word(bus, addr, cmd, (s->smb_data1 << 8) | s->smb_data0);

        }

        break;

    case 0x5:

        if (read) {

            s->smb_data0 = smbus_read_block(bus, addr, cmd, s->smb_data);

        } else {

            smbus_write_block(bus, addr, cmd, s->smb_data, s->smb_data0);

        }

        break;

    default:

        goto error;

    }

    return;

  error:

    s->smb_stat |= 0x04;

}

static void smb_ioport_writeb(void *opaque, hwaddr addr, uint64_t val,

                              unsigned width)

{

    PMSMBus *s = opaque;

    SMBUS_DPRINTF("SMB writeb port=0x%04x val=0x%02x\n", addr, val);

    switch(addr) {

    case SMBHSTSTS:

        s->smb_stat = 0;

        s->smb_index = 0;

        break;

    case SMBHSTCNT:

        s->smb_ctl = val;

        if (val & 0x40)

            smb_transaction(s);

        break;

    case SMBHSTCMD:

        s->smb_cmd = val;

        break;

    case SMBHSTADD:

        s->smb_addr = val;

        break;

    case SMBHSTDAT0:

        s->smb_data0 = val;

        break;

    case SMBHSTDAT1:

        s->smb_data1 = val;

        break;

    case SMBBLKDAT:

        s->smb_data[s->smb_index++] = val;

        if (s->smb_index > 31)

            s->smb_index = 0;

        break;

    default:

        break;

    }

}

static uint64_t smb_ioport_readb(void *opaque, hwaddr addr, unsigned width)

{

    PMSMBus *s = opaque;

    uint32_t val;

    switch(addr) {

    case SMBHSTSTS:

        val = s->smb_stat;

        break;

    case SMBHSTCNT:

        s->smb_index = 0;

        val = s->smb_ctl & 0x1f;

        break;

    case SMBHSTCMD:

        val = s->smb_cmd;

        break;

    case SMBHSTADD:

        val = s->smb_addr;

        break;

    case SMBHSTDAT0:

        val = s->smb_data0;

        break;

    case SMBHSTDAT1:

        val = s->smb_data1;

        break;

    case SMBBLKDAT:

        val = s->smb_data[s->smb_index++];

        if (s->smb_index > 31)

            s->smb_index = 0;

        break;

    default:

        val = 0;

        break;

    }

    SMBUS_DPRINTF("SMB readb port=0x%04x val=0x%02x\n", addr, val);

    return val;

}

static const MemoryRegionOps pm_smbus_ops = {

    .read = smb_ioport_readb,

    .write = smb_ioport_writeb,

    .valid.min_access_size = 1,

    .valid.max_access_size = 1,

    .endianness = DEVICE_LITTLE_ENDIAN,

};

void pm_smbus_init(DeviceState *parent, PMSMBus *smb)

{

    smb->smbus = i2c_init_bus(parent, "i2c");

    memory_region_init_io(&smb->io, &pm_smbus_ops, smb, "pm-smbus", 64);

}