/*

 * QEMU Parallel PORT emulation

 *

 * Copyright (c) 2003-2005 Fabrice Bellard

 * Copyright (c) 2007 Marko Kohtala

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "hw.h"

#include "qemu-char.h"

#include "isa.h"

#include "pc.h"

//#define DEBUG_PARALLEL

#ifdef DEBUG_PARALLEL

#define pdebug(fmt, arg...) printf("pp: " fmt, ##arg)

#else

#define pdebug(fmt, arg...) ((void)0)

#endif

#define PARA_REG_DATA 0

#define PARA_REG_STS 1

#define PARA_REG_CTR 2

#define PARA_REG_EPP_ADDR 3

#define PARA_REG_EPP_DATA 4

/*

 * These are the definitions for the Printer Status Register

 */

#define PARA_STS_BUSY	0x80	/* Busy complement */

#define PARA_STS_ACK	0x40	/* Acknowledge */

#define PARA_STS_PAPER	0x20	/* Out of paper */

#define PARA_STS_ONLINE	0x10	/* Online */

#define PARA_STS_ERROR	0x08	/* Error complement */

#define PARA_STS_TMOUT	0x01	/* EPP timeout */

/*

 * These are the definitions for the Printer Control Register

 */

#define PARA_CTR_DIR	0x20	/* Direction (1=read, 0=write) */

#define PARA_CTR_INTEN	0x10	/* IRQ Enable */

#define PARA_CTR_SELECT	0x08	/* Select In complement */

#define PARA_CTR_INIT	0x04	/* Initialize Printer complement */

#define PARA_CTR_AUTOLF	0x02	/* Auto linefeed complement */

#define PARA_CTR_STROBE	0x01	/* Strobe complement */

#define PARA_CTR_SIGNAL (PARA_CTR_SELECT|PARA_CTR_INIT|PARA_CTR_AUTOLF|PARA_CTR_STROBE)

struct ParallelState {

    uint8_t dataw;

    uint8_t datar;

    uint8_t status;

    uint8_t control;

    qemu_irq irq;

    int irq_pending;

    CharDriverState *chr;

    int hw_driver;

    int epp_timeout;

    uint32_t last_read_offset; /* For debugging */

    /* Memory-mapped interface */

    int it_shift;

};

static void parallel_update_irq(ParallelState *s)

{

    if (s->irq_pending)

        qemu_irq_raise(s->irq);

    else

        qemu_irq_lower(s->irq);

}

static void

parallel_ioport_write_sw(void *opaque, uint32_t addr, uint32_t val)

{

    ParallelState *s = opaque;

    pdebug("write addr=0x%02x val=0x%02x\n", addr, val);

    addr &= 7;

    switch(addr) {

    case PARA_REG_DATA:

        s->dataw = val;

        parallel_update_irq(s);

        break;

    case PARA_REG_CTR:

        val |= 0xc0;

        if ((val & PARA_CTR_INIT) == 0 ) {

            s->status = PARA_STS_BUSY;

            s->status |= PARA_STS_ACK;

            s->status |= PARA_STS_ONLINE;

            s->status |= PARA_STS_ERROR;

        }

        else if (val & PARA_CTR_SELECT) {

            if (val & PARA_CTR_STROBE) {

                s->status &= ~PARA_STS_BUSY;

                if ((s->control & PARA_CTR_STROBE) == 0)

                    qemu_chr_write(s->chr, &s->dataw, 1);

            } else {

                if (s->control & PARA_CTR_INTEN) {

                    s->irq_pending = 1;

                }

            }

        }

        parallel_update_irq(s);

        s->control = val;

        break;

    }

}

static void parallel_ioport_write_hw(void *opaque, uint32_t addr, uint32_t val)

{

    ParallelState *s = opaque;

    uint8_t parm = val;

    int dir;

    /* Sometimes programs do several writes for timing purposes on old

       HW. Take care not to waste time on writes that do nothing. */

    s->last_read_offset = ~0U;

    addr &= 7;

    switch(addr) {

    case PARA_REG_DATA:

        if (s->dataw == val)

            return;

        pdebug("wd%02x\n", val);

        qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_WRITE_DATA, &parm);

        s->dataw = val;

        break;

    case PARA_REG_STS:

        pdebug("ws%02x\n", val);

        if (val & PARA_STS_TMOUT)

            s->epp_timeout = 0;

        break;

    case PARA_REG_CTR:

        val |= 0xc0;

        if (s->control == val)

            return;

        pdebug("wc%02x\n", val);

        if ((val & PARA_CTR_DIR) != (s->control & PARA_CTR_DIR)) {

            if (val & PARA_CTR_DIR) {

                dir = 1;

            } else {

                dir = 0;

            }

            qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_DATA_DIR, &dir);

            parm &= ~PARA_CTR_DIR;

        }

        qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_WRITE_CONTROL, &parm);

        s->control = val;

        break;

    case PARA_REG_EPP_ADDR:

        if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT)

            /* Controls not correct for EPP address cycle, so do nothing */

            pdebug("wa%02x s\n", val);

        else {

            struct ParallelIOArg ioarg = { .buffer = &parm, .count = 1 };

            if (qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_EPP_WRITE_ADDR, &ioarg)) {

                s->epp_timeout = 1;

                pdebug("wa%02x t\n", val);

            }

            else

                pdebug("wa%02x\n", val);

        }

        break;

    case PARA_REG_EPP_DATA:

        if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT)

            /* Controls not correct for EPP data cycle, so do nothing */

            pdebug("we%02x s\n", val);

        else {

            struct ParallelIOArg ioarg = { .buffer = &parm, .count = 1 };

            if (qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg)) {

                s->epp_timeout = 1;

                pdebug("we%02x t\n", val);

            }

            else

                pdebug("we%02x\n", val);

        }

        break;

    }

}

static void

parallel_ioport_eppdata_write_hw2(void *opaque, uint32_t addr, uint32_t val)

{

    ParallelState *s = opaque;

    uint16_t eppdata = cpu_to_le16(val);

    int err;

    struct ParallelIOArg ioarg = {

        .buffer = &eppdata, .count = sizeof(eppdata)

    };

    if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT) {

        /* Controls not correct for EPP data cycle, so do nothing */

        pdebug("we%04x s\n", val);

        return;

    }

    err = qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg);

    if (err) {

        s->epp_timeout = 1;

        pdebug("we%04x t\n", val);

    }

    else

        pdebug("we%04x\n", val);

}

static void

parallel_ioport_eppdata_write_hw4(void *opaque, uint32_t addr, uint32_t val)

{

    ParallelState *s = opaque;

    uint32_t eppdata = cpu_to_le32(val);

    int err;

    struct ParallelIOArg ioarg = {

        .buffer = &eppdata, .count = sizeof(eppdata)

    };

    if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT) {

        /* Controls not correct for EPP data cycle, so do nothing */

        pdebug("we%08x s\n", val);

        return;

    }

    err = qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg);

    if (err) {

        s->epp_timeout = 1;

        pdebug("we%08x t\n", val);

    }

    else

        pdebug("we%08x\n", val);

}

static uint32_t parallel_ioport_read_sw(void *opaque, uint32_t addr)

{

    ParallelState *s = opaque;

    uint32_t ret = 0xff;

    addr &= 7;

    switch(addr) {

    case PARA_REG_DATA:

        if (s->control & PARA_CTR_DIR)

            ret = s->datar;

        else

            ret = s->dataw;

        break;

    case PARA_REG_STS:

        ret = s->status;

        s->irq_pending = 0;

        if ((s->status & PARA_STS_BUSY) == 0 && (s->control & PARA_CTR_STROBE) == 0) {

            /* XXX Fixme: wait 5 microseconds */

            if (s->status & PARA_STS_ACK)

                s->status &= ~PARA_STS_ACK;

            else {

                /* XXX Fixme: wait 5 microseconds */

                s->status |= PARA_STS_ACK;

                s->status |= PARA_STS_BUSY;

            }

        }

        parallel_update_irq(s);

        break;

    case PARA_REG_CTR:

        ret = s->control;

        break;

    }

    pdebug("read addr=0x%02x val=0x%02x\n", addr, ret);

    return ret;

}

static uint32_t parallel_ioport_read_hw(void *opaque, uint32_t addr)

{

    ParallelState *s = opaque;

    uint8_t ret = 0xff;

    addr &= 7;

    switch(addr) {

    case PARA_REG_DATA:

        qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_READ_DATA, &ret);

        if (s->last_read_offset != addr || s->datar != ret)

            pdebug("rd%02x\n", ret);

        s->datar = ret;

        break;

    case PARA_REG_STS:

        qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_READ_STATUS, &ret);

        ret &= ~PARA_STS_TMOUT;

        if (s->epp_timeout)

            ret |= PARA_STS_TMOUT;

        if (s->last_read_offset != addr || s->status != ret)

            pdebug("rs%02x\n", ret);

        s->status = ret;

        break;

    case PARA_REG_CTR:

        /* s->control has some bits fixed to 1. It is zero only when

           it has not been yet written to.  */

        if (s->control == 0) {

            qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_READ_CONTROL, &ret);

            if (s->last_read_offset != addr)

                pdebug("rc%02x\n", ret);

            s->control = ret;

        }

        else {

            ret = s->control;

            if (s->last_read_offset != addr)

                pdebug("rc%02x\n", ret);

        }

        break;

    case PARA_REG_EPP_ADDR:

        if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != (PARA_CTR_DIR|PARA_CTR_INIT))

            /* Controls not correct for EPP addr cycle, so do nothing */

            pdebug("ra%02x s\n", ret);

        else {

            struct ParallelIOArg ioarg = { .buffer = &ret, .count = 1 };

            if (qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_EPP_READ_ADDR, &ioarg)) {

                s->epp_timeout = 1;

                pdebug("ra%02x t\n", ret);

            }

            else

                pdebug("ra%02x\n", ret);

        }

        break;

    case PARA_REG_EPP_DATA:

        if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != (PARA_CTR_DIR|PARA_CTR_INIT))

            /* Controls not correct for EPP data cycle, so do nothing */

            pdebug("re%02x s\n", ret);

        else {

            struct ParallelIOArg ioarg = { .buffer = &ret, .count = 1 };

            if (qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg)) {

                s->epp_timeout = 1;

                pdebug("re%02x t\n", ret);

            }

            else

                pdebug("re%02x\n", ret);

        }

        break;

    }

    s->last_read_offset = addr;

    return ret;

}

static uint32_t

parallel_ioport_eppdata_read_hw2(void *opaque, uint32_t addr)

{

    ParallelState *s = opaque;

    uint32_t ret;

    uint16_t eppdata = ~0;

    int err;

    struct ParallelIOArg ioarg = {

        .buffer = &eppdata, .count = sizeof(eppdata)

    };

    if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != (PARA_CTR_DIR|PARA_CTR_INIT)) {

        /* Controls not correct for EPP data cycle, so do nothing */

        pdebug("re%04x s\n", eppdata);

        return eppdata;

    }

    err = qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg);

    ret = le16_to_cpu(eppdata);

    if (err) {

        s->epp_timeout = 1;

        pdebug("re%04x t\n", ret);

    }

    else

        pdebug("re%04x\n", ret);

    return ret;

}

static uint32_t

parallel_ioport_eppdata_read_hw4(void *opaque, uint32_t addr)

{

    ParallelState *s = opaque;

    uint32_t ret;

    uint32_t eppdata = ~0U;

    int err;

    struct ParallelIOArg ioarg = {

        .buffer = &eppdata, .count = sizeof(eppdata)

    };

    if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != (PARA_CTR_DIR|PARA_CTR_INIT)) {

        /* Controls not correct for EPP data cycle, so do nothing */

        pdebug("re%08x s\n", eppdata);

        return eppdata;

    }

    err = qemu_chr_ioctl(s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg);

    ret = le32_to_cpu(eppdata);

    if (err) {

        s->epp_timeout = 1;

        pdebug("re%08x t\n", ret);

    }

    else

        pdebug("re%08x\n", ret);

    return ret;

}

static void parallel_ioport_ecp_write(void *opaque, uint32_t addr, uint32_t val)

{

    addr &= 7;

    pdebug("wecp%d=%02x\n", addr, val);

}

static uint32_t parallel_ioport_ecp_read(void *opaque, uint32_t addr)

{

    uint8_t ret = 0xff;

    addr &= 7;

    pdebug("recp%d:%02x\n", addr, ret);

    return ret;

}

static void parallel_reset(void *opaque)

{

    ParallelState *s = opaque;

    s->datar = ~0;

    s->dataw = ~0;

    s->status = PARA_STS_BUSY;

    s->status |= PARA_STS_ACK;

    s->status |= PARA_STS_ONLINE;

    s->status |= PARA_STS_ERROR;

    s->status |= PARA_STS_TMOUT;

    s->control = PARA_CTR_SELECT;

    s->control |= PARA_CTR_INIT;

    s->control |= 0xc0;

    s->irq_pending = 0;

    s->hw_driver = 0;

    s->epp_timeout = 0;

    s->last_read_offset = ~0U;

}

/* If fd is zero, it means that the parallel device uses the console */

ParallelState *parallel_init(int base, qemu_irq irq, CharDriverState *chr)

{

    ParallelState *s;

    uint8_t dummy;

    s = qemu_mallocz(sizeof(ParallelState));

    if (!s)

        return NULL;

    s->irq = irq;

    s->chr = chr;

    parallel_reset(s);

    qemu_register_reset(parallel_reset, s);

    if (qemu_chr_ioctl(chr, CHR_IOCTL_PP_READ_STATUS, &dummy) == 0) {

        s->hw_driver = 1;

        s->status = dummy;

    }

    if (s->hw_driver) {

        register_ioport_write(base, 8, 1, parallel_ioport_write_hw, s);

        register_ioport_read(base, 8, 1, parallel_ioport_read_hw, s);

        register_ioport_write(base+4, 1, 2, parallel_ioport_eppdata_write_hw2, s);

        register_ioport_read(base+4, 1, 2, parallel_ioport_eppdata_read_hw2, s);

        register_ioport_write(base+4, 1, 4, parallel_ioport_eppdata_write_hw4, s);

        register_ioport_read(base+4, 1, 4, parallel_ioport_eppdata_read_hw4, s);

        register_ioport_write(base+0x400, 8, 1, parallel_ioport_ecp_write, s);

        register_ioport_read(base+0x400, 8, 1, parallel_ioport_ecp_read, s);

    }

    else {

        register_ioport_write(base, 8, 1, parallel_ioport_write_sw, s);

        register_ioport_read(base, 8, 1, parallel_ioport_read_sw, s);

    }

    return s;

}

/* Memory mapped interface */

static uint32_t parallel_mm_readb (void *opaque, target_phys_addr_t addr)

{

    ParallelState *s = opaque;

    return parallel_ioport_read_sw(s, addr >> s->it_shift) & 0xFF;

}

static void parallel_mm_writeb (void *opaque,

                                target_phys_addr_t addr, uint32_t value)

{

    ParallelState *s = opaque;

    parallel_ioport_write_sw(s, addr >> s->it_shift, value & 0xFF);

}

static uint32_t parallel_mm_readw (void *opaque, target_phys_addr_t addr)

{

    ParallelState *s = opaque;

    return parallel_ioport_read_sw(s, addr >> s->it_shift) & 0xFFFF;

}

static void parallel_mm_writew (void *opaque,

                                target_phys_addr_t addr, uint32_t value)

{

    ParallelState *s = opaque;

    parallel_ioport_write_sw(s, addr >> s->it_shift, value & 0xFFFF);

}

static uint32_t parallel_mm_readl (void *opaque, target_phys_addr_t addr)

{

    ParallelState *s = opaque;

    return parallel_ioport_read_sw(s, addr >> s->it_shift);

}

static void parallel_mm_writel (void *opaque,

                                target_phys_addr_t addr, uint32_t value)

{

    ParallelState *s = opaque;

    parallel_ioport_write_sw(s, addr >> s->it_shift, value);

}

static CPUReadMemoryFunc *parallel_mm_read_sw[] = {

    &parallel_mm_readb,

    &parallel_mm_readw,

    &parallel_mm_readl,

};