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/* 

 * QEMU LSI53C895A SCSI Host Bus Adapter emulation

 *

 * Copyright (c) 2006 CodeSourcery.

 * Written by Paul Brook

 *

 * This code is licenced under the LGPL.

 */

/* ??? Need to check if the {read,write}[wl] routines work properly on

   big-endian targets.  */

#include "vl.h"

//#define DEBUG_LSI

//#define DEBUG_LSI_REG

#ifdef DEBUG_LSI

#define DPRINTF(fmt, args...) \

do { printf("lsi_scsi: " fmt , ##args); } while (0)

#define BADF(fmt, args...) \

do { fprintf(stderr, "lsi_scsi: " fmt , ##args); exit(1);} while (0)

#else

#define DPRINTF(fmt, args...) do {} while(0)

#define BADF(fmt, args...) \

do { fprintf(stderr, "lsi_scsi: " fmt , ##args); } while (0)

#endif

#define LSI_SCNTL0_TRG    0x01

#define LSI_SCNTL0_AAP    0x02

#define LSI_SCNTL0_EPC    0x08

#define LSI_SCNTL0_WATN   0x10

#define LSI_SCNTL0_START  0x20

#define LSI_SCNTL1_SST    0x01

#define LSI_SCNTL1_IARB   0x02

#define LSI_SCNTL1_AESP   0x04

#define LSI_SCNTL1_RST    0x08

#define LSI_SCNTL1_CON    0x10

#define LSI_SCNTL1_DHP    0x20

#define LSI_SCNTL1_ADB    0x40

#define LSI_SCNTL1_EXC    0x80

#define LSI_SCNTL2_WSR    0x01

#define LSI_SCNTL2_VUE0   0x02

#define LSI_SCNTL2_VUE1   0x04

#define LSI_SCNTL2_WSS    0x08

#define LSI_SCNTL2_SLPHBEN 0x10

#define LSI_SCNTL2_SLPMD  0x20

#define LSI_SCNTL2_CHM    0x40

#define LSI_SCNTL2_SDU    0x80

#define LSI_ISTAT0_DIP    0x01

#define LSI_ISTAT0_SIP    0x02

#define LSI_ISTAT0_INTF   0x04

#define LSI_ISTAT0_CON    0x08

#define LSI_ISTAT0_SEM    0x10

#define LSI_ISTAT0_SIGP   0x20

#define LSI_ISTAT0_SRST   0x40

#define LSI_ISTAT0_ABRT   0x80

#define LSI_ISTAT1_SI     0x01

#define LSI_ISTAT1_SRUN   0x02

#define LSI_ISTAT1_FLSH   0x04

#define LSI_SSTAT0_SDP0   0x01

#define LSI_SSTAT0_RST    0x02

#define LSI_SSTAT0_WOA    0x04

#define LSI_SSTAT0_LOA    0x08

#define LSI_SSTAT0_AIP    0x10

#define LSI_SSTAT0_OLF    0x20

#define LSI_SSTAT0_ORF    0x40

#define LSI_SSTAT0_ILF    0x80

#define LSI_SIST0_PAR     0x01

#define LSI_SIST0_RST     0x02

#define LSI_SIST0_UDC     0x04

#define LSI_SIST0_SGE     0x08

#define LSI_SIST0_RSL     0x10

#define LSI_SIST0_SEL     0x20

#define LSI_SIST0_CMP     0x40

#define LSI_SIST0_MA      0x80

#define LSI_SIST1_HTH     0x01

#define LSI_SIST1_GEN     0x02

#define LSI_SIST1_STO     0x04

#define LSI_SIST1_SBMC    0x10

#define LSI_SOCL_IO       0x01

#define LSI_SOCL_CD       0x02

#define LSI_SOCL_MSG      0x04

#define LSI_SOCL_ATN      0x08

#define LSI_SOCL_SEL      0x10

#define LSI_SOCL_BSY      0x20

#define LSI_SOCL_ACK      0x40

#define LSI_SOCL_REQ      0x80

#define LSI_DSTAT_IID     0x01

#define LSI_DSTAT_SIR     0x04

#define LSI_DSTAT_SSI     0x08

#define LSI_DSTAT_ABRT    0x10

#define LSI_DSTAT_BF      0x20

#define LSI_DSTAT_MDPE    0x40

#define LSI_DSTAT_DFE     0x80

#define LSI_DCNTL_COM     0x01

#define LSI_DCNTL_IRQD    0x02

#define LSI_DCNTL_STD     0x04

#define LSI_DCNTL_IRQM    0x08

#define LSI_DCNTL_SSM     0x10

#define LSI_DCNTL_PFEN    0x20

#define LSI_DCNTL_PFF     0x40

#define LSI_DCNTL_CLSE    0x80

#define LSI_DMODE_MAN     0x01

#define LSI_DMODE_BOF     0x02

#define LSI_DMODE_ERMP    0x04

#define LSI_DMODE_ERL     0x08

#define LSI_DMODE_DIOM    0x10

#define LSI_DMODE_SIOM    0x20

#define LSI_CTEST2_DACK   0x01

#define LSI_CTEST2_DREQ   0x02

#define LSI_CTEST2_TEOP   0x04

#define LSI_CTEST2_PCICIE 0x08

#define LSI_CTEST2_CM     0x10

#define LSI_CTEST2_CIO    0x20

#define LSI_CTEST2_SIGP   0x40

#define LSI_CTEST2_DDIR   0x80

#define LSI_CTEST5_BL2    0x04

#define LSI_CTEST5_DDIR   0x08

#define LSI_CTEST5_MASR   0x10

#define LSI_CTEST5_DFSN   0x20

#define LSI_CTEST5_BBCK   0x40

#define LSI_CTEST5_ADCK   0x80

#define LSI_CCNTL0_DILS   0x01

#define LSI_CCNTL0_DISFC  0x10

#define LSI_CCNTL0_ENNDJ  0x20

#define LSI_CCNTL0_PMJCTL 0x40

#define LSI_CCNTL0_ENPMJ  0x80

#define PHASE_DO          0

#define PHASE_DI          1

#define PHASE_CMD         2

#define PHASE_ST          3

#define PHASE_MO          6

#define PHASE_MI          7

#define PHASE_MASK        7

/* The HBA is ID 7, so for simplicitly limit to 7 devices.  */

#define LSI_MAX_DEVS      7

typedef struct {

    PCIDevice pci_dev;

    int mmio_io_addr;

    int ram_io_addr;

    uint32_t script_ram_base;

    uint32_t data_len;

    int carry; /* ??? Should this be an a visible register somewhere?  */

    int sense;

    uint8_t msg;

    /* Nonzero if a Wait Reselect instruction has been issued.  */

    int waiting;

    SCSIDevice *scsi_dev[LSI_MAX_DEVS];

    SCSIDevice *current_dev;

    int current_lun;

    uint32_t dsa;

    uint32_t temp;

    uint32_t dnad;

    uint32_t dbc;

    uint8_t istat0;

    uint8_t istat1;

    uint8_t dcmd;

    uint8_t dstat;

    uint8_t dien;

    uint8_t sist0;

    uint8_t sist1;

    uint8_t sien0;

    uint8_t sien1;

    uint8_t mbox0;

    uint8_t mbox1;

    uint8_t dfifo;

    uint8_t ctest3;

    uint8_t ctest4;

    uint8_t ctest5;

    uint8_t ccntl0;

    uint8_t ccntl1;

    uint32_t dsp;

    uint32_t dsps;

    uint8_t dmode;

    uint8_t dcntl;

    uint8_t scntl0;

    uint8_t scntl1;

    uint8_t scntl2;

    uint8_t scntl3;

    uint8_t sstat0;

    uint8_t sstat1;

    uint8_t scid;

    uint8_t sxfer;

    uint8_t socl;

    uint8_t sdid;

    uint8_t sfbr;

    uint8_t stest1;

    uint8_t stest2;

    uint8_t stest3;

    uint8_t stime0;

    uint8_t respid0;

    uint8_t respid1;

    uint32_t mmrs;

    uint32_t mmws;

    uint32_t sfs;

    uint32_t drs;

    uint32_t sbms;

    uint32_t dmbs;

    uint32_t dnad64;

    uint32_t pmjad1;

    uint32_t pmjad2;

    uint32_t rbc;

    uint32_t ua;

    uint32_t ia;

    uint32_t sbc;

    uint32_t csbc;

    uint32_t scratch[13]; /* SCRATCHA-SCRATCHR */

    /* Script ram is stored as 32-bit words in host byteorder.  */

    uint32_t script_ram[2048];

} LSIState;

static void lsi_soft_reset(LSIState *s)

{

    DPRINTF("Reset\n");

    s->carry = 0;

    s->waiting = 0;

    s->dsa = 0;

    s->dnad = 0;

    s->dbc = 0;

    s->temp = 0;

    memset(s->scratch, 0, sizeof(s->scratch));

    s->istat0 = 0;

    s->istat1 = 0;

    s->dcmd = 0;

    s->dstat = 0;

    s->dien = 0;

    s->sist0 = 0;

    s->sist1 = 0;

    s->sien0 = 0;

    s->sien1 = 0;

    s->mbox0 = 0;

    s->mbox1 = 0;

    s->dfifo = 0;

    s->ctest3 = 0;

    s->ctest4 = 0;

    s->ctest5 = 0;

    s->ccntl0 = 0;

    s->ccntl1 = 0;

    s->dsp = 0;

    s->dsps = 0;

    s->dmode = 0;

    s->dcntl = 0;

    s->scntl0 = 0xc0;

    s->scntl1 = 0;

    s->scntl2 = 0;

    s->scntl3 = 0;

    s->sstat0 = 0;

    s->sstat1 = 0;

    s->scid = 7;

    s->sxfer = 0;

    s->socl = 0;

    s->stest1 = 0;

    s->stest2 = 0;

    s->stest3 = 0;

    s->stime0 = 0;

    s->respid0 = 0x80;

    s->respid1 = 0;

    s->mmrs = 0;

    s->mmws = 0;

    s->sfs = 0;

    s->drs = 0;

    s->sbms = 0;

    s->dmbs = 0;

    s->dnad64 = 0;

    s->pmjad1 = 0;

    s->pmjad2 = 0;

    s->rbc = 0;

    s->ua = 0;

    s->ia = 0;

    s->sbc = 0;

    s->csbc = 0;

}

static uint8_t lsi_reg_readb(LSIState *s, int offset);

static void lsi_reg_writeb(LSIState *s, int offset, uint8_t val);

static inline uint32_t read_dword(LSIState *s, uint32_t addr)

{

    uint32_t buf;

    /* Optimize reading from SCRIPTS RAM.  */

    if ((addr & 0xffffe000) == s->script_ram_base) {

        return s->script_ram[(addr & 0x1fff) >> 2];

    }

    cpu_physical_memory_read(addr, (uint8_t *)&buf, 4);

    return cpu_to_le32(buf);

}

static void lsi_stop_script(LSIState *s)

{

    s->istat1 &= ~LSI_ISTAT1_SRUN;

}

static void lsi_update_irq(LSIState *s)

{

    int level;

    static int last_level;

    /* It's unclear whether the DIP/SIP bits should be cleared when the

       Interrupt Status Registers are cleared or when istat0 is read.

       We currently do the formwer, which seems to work.  */

    level = 0;

    if (s->dstat) {

        if (s->dstat & s->dien)

            level = 1;

        s->istat0 |= LSI_ISTAT0_DIP;

    } else {

        s->istat0 &= ~LSI_ISTAT0_DIP;

    }

    if (s->sist0 || s->sist1) {

        if ((s->sist0 & s->sien0) || (s->sist1 & s->sien1))

            level = 1;

        s->istat0 |= LSI_ISTAT0_SIP;

    } else {

        s->istat0 &= ~LSI_ISTAT0_SIP;

    }

    if (s->istat0 & LSI_ISTAT0_INTF)

        level = 1;

    if (level != last_level) {

        DPRINTF("Update IRQ level %d dstat %02x sist %02x%02x\n",

                level, s->dstat, s->sist1, s->sist0);

        last_level = level;

    }

    pci_set_irq(&s->pci_dev, 0, level);

}

/* Stop SCRIPTS execution and raise a SCSI interrupt.  */

static void lsi_script_scsi_interrupt(LSIState *s, int stat0, int stat1)

{

    uint32_t mask0;

    uint32_t mask1;

    DPRINTF("SCSI Interrupt 0x%02x%02x prev 0x%02x%02x\n",

            stat1, stat0, s->sist1, s->sist0);

    s->sist0 |= stat0;

    s->sist1 |= stat1;

    /* Stop processor on fatal or unmasked interrupt.  As a special hack

       we don't stop processing when raising STO.  Instead continue

       execution and stop at the next insn that accesses the SCSI bus.  */

    mask0 = s->sien0 | ~(LSI_SIST0_CMP | LSI_SIST0_SEL | LSI_SIST0_RSL);

    mask1 = s->sien1 | ~(LSI_SIST1_GEN | LSI_SIST1_HTH);

    mask1 &= ~LSI_SIST1_STO;

    if (s->sist0 & mask0 || s->sist1 & mask1) {

        lsi_stop_script(s);

    }

    lsi_update_irq(s);

}

/* Stop SCRIPTS execution and raise a DMA interrupt.  */

static void lsi_script_dma_interrupt(LSIState *s, int stat)

{

    DPRINTF("DMA Interrupt 0x%x prev 0x%x\n", stat, s->dstat);

    s->dstat |= stat;

    lsi_update_irq(s);

    lsi_stop_script(s);

}

static inline void lsi_set_phase(LSIState *s, int phase)

{

    s->sstat1 = (s->sstat1 & ~PHASE_MASK) | phase;

}

static void lsi_bad_phase(LSIState *s, int out, int new_phase)

{

    /* Trigger a phase mismatch.  */

    if (s->ccntl0 & LSI_CCNTL0_ENPMJ) {

        if ((s->ccntl0 & LSI_CCNTL0_PMJCTL) || out) {

            s->dsp = s->pmjad1;

        } else {

            s->dsp = s->pmjad2;

        }

        DPRINTF("Data phase mismatch jump to %08x\n", s->dsp);

    } else {

        DPRINTF("Phase mismatch interrupt\n");

        lsi_script_scsi_interrupt(s, LSI_SIST0_MA, 0);

        lsi_stop_script(s);

    }

    lsi_set_phase(s, new_phase);

}

static void lsi_do_dma(LSIState *s, int out)

{

    uint8_t buf[TARGET_PAGE_SIZE];

    uint32_t addr;

    uint32_t count;

    int n;

    count = s->dbc;

    addr = s->dnad;

    DPRINTF("DMA %s addr=0x%08x len=%d avail=%d\n", out ? "out" : "in",

            addr, count, s->data_len);

    /* ??? Too long transfers are truncated. Don't know if this is the

       correct behavior.  */

    if (count > s->data_len) {

        /* If the DMA length is greater then the device data length then

           a phase mismatch will occur.  */

        count = s->data_len;

        s->dbc = count;

        lsi_bad_phase(s, out, PHASE_ST);

    }

    s->csbc += count;

    /* ??? Set SFBR to first data byte.  */

    while (count) {

        n = (count > TARGET_PAGE_SIZE) ? TARGET_PAGE_SIZE : count;

        if (out) {

            cpu_physical_memory_read(addr, buf, n);

            scsi_write_data(s->current_dev, buf, n);

        } else {

            scsi_read_data(s->current_dev, buf, n);

            cpu_physical_memory_write(addr, buf, n);

        }

        addr += n;

        count -= n;

    }

}

static void lsi_do_command(LSIState *s)

{

    uint8_t buf[16];

    int n;

    DPRINTF("Send command len=%d\n", s->dbc);

    if (s->dbc > 16)

        s->dbc = 16;

    cpu_physical_memory_read(s->dnad, buf, s->dbc);

    s->sfbr = buf[0];

    n = scsi_send_command(s->current_dev, 0, buf, s->current_lun);

    if (n > 0) {

        s->data_len = n;

        lsi_set_phase(s, PHASE_DI);

    } else if (n < 0) {

        s->data_len = -n;

        lsi_set_phase(s, PHASE_DO);

    }

}

static void lsi_command_complete(void *opaque, uint32_t tag, int sense)

{

    LSIState *s = (LSIState *)opaque;

    DPRINTF("Command complete sense=%d\n", sense);

    s->sense = sense;

    lsi_set_phase(s, PHASE_ST);

}

static void lsi_do_status(LSIState *s)

{

    DPRINTF("Get status len=%d sense=%d\n", s->dbc, s->sense);

    if (s->dbc != 1)

        BADF("Bad Status move\n");

    s->dbc = 1;

    s->msg = s->sense;

    cpu_physical_memory_write(s->dnad, &s->msg, 1);

    s->sfbr = s->msg;

    lsi_set_phase(s, PHASE_MI);

    s->msg = 0; /* COMMAND COMPLETE */

}

static void lsi_disconnect(LSIState *s)

{

    s->scntl1 &= ~LSI_SCNTL1_CON;

    s->sstat1 &= ~PHASE_MASK;

}

static void lsi_do_msgin(LSIState *s)

{

    DPRINTF("Message in len=%d\n", s->dbc);

    s->dbc = 1;

    s->sfbr = s->msg;

    cpu_physical_memory_write(s->dnad, &s->msg, 1);

    if (s->msg == 0) {

        lsi_disconnect(s);

    } else {

        /* ??? Check if ATN (not yet implemented) is asserted and maybe

           switch to PHASE_MO.  */

        lsi_set_phase(s, PHASE_CMD);

    }

}

static void lsi_do_msgout(LSIState *s)

{

    uint8_t msg;

    DPRINTF("MSG out len=%d\n", s->dbc);

    if (s->dbc != 1) {

        /* Multibyte messages not implemented.  */

        s->msg = 7; /* MESSAGE REJECT */

        //s->dbc = 1;

        //lsi_bad_phase(s, 1, PHASE_MI);

        lsi_set_phase(s, PHASE_MI);

        return;

    }

    cpu_physical_memory_read(s->dnad, &msg, 1);

    s->sfbr = msg;

    s->dnad++;

    switch (msg) {

    case 0x00:

        DPRINTF("Got Disconnect\n");

        lsi_disconnect(s);

        return;

    case 0x08:

        DPRINTF("Got No Operation\n");

        lsi_set_phase(s, PHASE_CMD);

        return;

    }

    if ((msg & 0x80) == 0) {

        DPRINTF("Unimplemented message 0x%d\n", msg);

        s->msg = 7; /* MESSAGE REJECT */

        lsi_bad_phase(s, 1, PHASE_MI);

        return;

    }

    s->current_lun = msg & 7;

    DPRINTF("Select LUN %d\n", s->current_lun);

    lsi_set_phase(s, PHASE_CMD);

}

/* Sign extend a 24-bit value.  */

static inline int32_t sxt24(int32_t n)

{

    return (n << 8) >> 8;

}

static void lsi_memcpy(LSIState *s, uint32_t dest, uint32_t src, int count)

{

    int n;

    uint8_t buf[TARGET_PAGE_SIZE];

    DPRINTF("memcpy dest 0x%08x src 0x%08x count %d\n", dest, src, count);

    while (count) {

        n = (count > TARGET_PAGE_SIZE) ? TARGET_PAGE_SIZE : count;

        cpu_physical_memory_read(src, buf, n);

        cpu_physical_memory_write(dest, buf, n);

        src += n;

        dest += n;

        count -= n;

    }

}

static void lsi_execute_script(LSIState *s)

{

    uint32_t insn;

    uint32_t addr;

    int opcode;

    s->istat1 |= LSI_ISTAT1_SRUN;

again:

    insn = read_dword(s, s->dsp);

    addr = read_dword(s, s->dsp + 4);

    DPRINTF("SCRIPTS dsp=%08x opcode %08x arg %08x\n", s->dsp, insn, addr);

    s->dsps = addr;

    s->dcmd = insn >> 24;

    s->dsp += 8;

    switch (insn >> 30) {

    case 0: /* Block move.  */

        if (s->sist1 & LSI_SIST1_STO) {

            DPRINTF("Delayed select timeout\n");

            lsi_stop_script(s);

            break;

        }

        s->dbc = insn & 0xffffff;

        s->rbc = s->dbc;

        if (insn & (1 << 29)) {

            /* Indirect addressing.  */

            addr = read_dword(s, addr);

        } else if (insn & (1 << 28)) {

            uint32_t buf[2];

            int32_t offset;

            /* Table indirect addressing.  */

            offset = sxt24(addr);

            cpu_physical_memory_read(s->dsa + offset, (uint8_t *)buf, 8);

            s->dbc = cpu_to_le32(buf[0]);

            addr = cpu_to_le32(buf[1]);

        }

        if ((s->sstat1 & PHASE_MASK) != ((insn >> 24) & 7)) {

            DPRINTF("Wrong phase got %d expected %d\n",

                    s->sstat1 & PHASE_MASK, (insn >> 24) & 7);

            lsi_script_scsi_interrupt(s, LSI_SIST0_MA, 0);

            break;

        }

        s->dnad = addr;

        switch (s->sstat1 & 0x7) {

        case PHASE_DO:

            lsi_do_dma(s, 1);

            break;

        case PHASE_DI:

            lsi_do_dma(s, 0);

            break;

        case PHASE_CMD:

            lsi_do_command(s);

            break;

        case PHASE_ST:

            lsi_do_status(s);

            break;

        case PHASE_MO:

            lsi_do_msgout(s);

            break;

        case PHASE_MI:

            lsi_do_msgin(s);

            break;

        default:

            BADF("Unimplemented phase %d\n", s->sstat1 & PHASE_MASK);

            exit(1);

        }

        s->dfifo = s->dbc & 0xff;

        s->ctest5 = (s->ctest5 & 0xfc) | ((s->dbc >> 8) & 3);

        s->sbc = s->dbc;

        s->rbc -= s->dbc;

        s->ua = addr + s->dbc;

        /* ??? Set ESA.  */

        s->ia = s->dsp - 8;

        break;

    case 1: /* IO or Read/Write instruction.  */

        opcode = (insn >> 27) & 7;

        if (opcode < 5) {

            uint32_t id;

            if (insn & (1 << 25)) {

                id = read_dword(s, s->dsa + sxt24(insn));

            } else {

                id = addr;

            }

            id = (id >> 16) & 0xf;

            if (insn & (1 << 26)) {

                addr = s->dsp + sxt24(addr);

            }

            s->dnad = addr;

            switch (opcode) {

            case 0: /* Select */

                s->sstat0 |= LSI_SSTAT0_WOA;

                s->scntl1 &= ~LSI_SCNTL1_IARB;

                s->sdid = id;

                if (id >= LSI_MAX_DEVS || !s->scsi_dev[id]) {

                    DPRINTF("Selected absent target %d\n", id);

                    lsi_script_scsi_interrupt(s, 0, LSI_SIST1_STO);

                    lsi_disconnect(s);

                    break;

                }

                DPRINTF("Selected target %d%s\n",

                        id, insn & (1 << 3) ? " ATN" : "");

                /* ??? Linux drivers compain when this is set.  Maybe

                   it only applies in low-level mode (unimplemented).

                lsi_script_scsi_interrupt(s, LSI_SIST0_CMP, 0); */

                s->current_dev = s->scsi_dev[id];

                s->scntl1 |= LSI_SCNTL1_CON;

                if (insn & (1 << 3)) {

                    s->socl |= LSI_SOCL_ATN;

                }

                lsi_set_phase(s, PHASE_MO);

                break;

            case 1: /* Disconnect */

                DPRINTF("Wait Disconect\n");

                s->scntl1 &= ~LSI_SCNTL1_CON;

                break;

            case 2: /* Wait Reselect */

                DPRINTF("Wait Reselect\n");

                s->waiting = 1;

                break;

            case 3: /* Set */

                DPRINTF("Set%s%s%s%s\n",

                        insn & (1 << 3) ? " ATN" : "",

                        insn & (1 << 6) ? " ACK" : "",

                        insn & (1 << 9) ? " TM" : "",

                        insn & (1 << 10) ? " CC" : "");

                if (insn & (1 << 3)) {

                    s->socl |= LSI_SOCL_ATN;

                    lsi_set_phase(s, PHASE_MO);

                }

                if (insn & (1 << 9)) {

                    BADF("Target mode not implemented\n");

                    exit(1);

                }

                if (insn & (1 << 10))

                    s->carry = 1;

                break;

            case 4: /* Clear */

                DPRINTF("Clear%s%s%s%s\n",

                        insn & (1 << 3) ? " ATN" : "",

                        insn & (1 << 6) ? " ACK" : "",

                        insn & (1 << 9) ? " TM" : "",

                        insn & (1 << 10) ? " CC" : "");

                if (insn & (1 << 3)) {

                    s->socl &= ~LSI_SOCL_ATN;

                }

                if (insn & (1 << 10))

                    s->carry = 0;

                break;

            }

        } else {

            uint8_t op0;

            uint8_t op1;

            uint8_t data8;

            int reg;

            int operator;

#ifdef DEBUG_LSI

            static const char *opcode_names[3] =

                {"Write", "Read", "Read-Modify-Write"};

            static const char *operator_names[8] =

                {"MOV", "SHL", "OR", "XOR", "AND", "SHR", "ADD", "ADC"};

#endif

            reg = ((insn >> 16) & 0x7f) | (insn & 0x80);

            data8 = (insn >> 8) & 0xff;

            opcode = (insn >> 27) & 7;

            operator = (insn >> 24) & 7;

            DPRINTF("%s reg 0x%x %s data8 %d%s\n",

                    opcode_names[opcode - 5], reg,

                    operator_names[operator], data8,

                    (insn & (1 << 23)) ? " SFBR" : "");

            op0 = op1 = 0;

            switch (opcode) {

            case 5: /* From SFBR */

                op0 = s->sfbr;

                op1 = data8;

                break;

            case 6: /* To SFBR */

                if (operator)

                    op0 = lsi_reg_readb(s, reg);

                op1 = data8;

                break;

            case 7: /* Read-modify-write */

                if (operator)

                    op0 = lsi_reg_readb(s, reg);

                if (insn & (1 << 23)) {

                    op1 = s->sfbr;

                } else {

                    op1 = data8;

                }

                break;

            }

            switch (operator) {

            case 0: /* move */

                op0 = op1;

                break;

            case 1: /* Shift left */

                op1 = op0 >> 7;

                op0 = (op0 << 1) | s->carry;

                s->carry = op1;

                break;

            case 2: /* OR */

                op0 |= op1;

                break;

            case 3: /* XOR */

                op0 |= op1;

                break;

            case 4: /* AND */

                op0 &= op1;

                break;

            case 5: /* SHR */

                op1 = op0 & 1;

                op0 = (op0 >> 1) | (s->carry << 7);

                break;

            case 6: /* ADD */

                op0 += op1;

                s->carry = op0 < op1;

                break;

            case 7: /* ADC */

                op0 += op1 + s->carry;

                if (s->carry)

                    s->carry = op0 <= op1;

                else

                    s->carry = op0 < op1;

                break;

            }

            switch (opcode) {

            case 5: /* From SFBR */

            case 7: /* Read-modify-write */

                lsi_reg_writeb(s, reg, op0);

                break;

            case 6: /* To SFBR */

                s->sfbr = op0;

                break;

            }

        }

        break;

    case 2: /* Transfer Control.  */

        {

            int cond;

            int jmp;

            if ((insn & 0x002e0000) == 0) {

                DPRINTF("NOP\n");

                break;

            }

            if (s->sist1 & LSI_SIST1_STO) {

                DPRINTF("Delayed select timeout\n");

                lsi_stop_script(s);

                break;

            }

            cond = jmp = (insn & (1 << 19)) != 0;

            if (cond == jmp && (insn & (1 << 21))) {

                DPRINTF("Compare carry %d\n", s->carry == jmp);

                cond = s->carry != 0;

            }

            if (cond == jmp && (insn & (1 << 17))) {

                DPRINTF("Compare phase %d %c= %d\n",

                        (s->sstat1 & PHASE_MASK),

                        jmp ? '=' : '!',

                        ((insn >> 24) & 7));

                cond = (s->sstat1 & PHASE_MASK) == ((insn >> 24) & 7);

            }

            if (cond == jmp && (insn & (1 << 18))) {

                uint8_t mask;

                mask = (~insn >> 8) & 0xff;

                DPRINTF("Compare data 0x%x & 0x%x %c= 0x%x\n",

                        s->sfbr, mask, jmp ? '=' : '!', insn & mask);

                cond = (s->sfbr & mask) == (insn & mask);

            }

            if (cond == jmp) {

                if (insn & (1 << 23)) {

                    /* Relative address.  */

                    addr = s->dsp + sxt24(addr);

                }

                switch ((insn >> 27) & 7) {

                case 0: /* Jump */

                    DPRINTF("Jump to 0x%08x\n", addr);

                    s->dsp = addr;

                    break;

                case 1: /* Call */

                    DPRINTF("Call 0x%08x\n", addr);

                    s->temp = s->dsp;

                    s->dsp = addr;