Archipelago » qemu

/*

 * QEMU ESP emulation

 * 

 * Copyright (c) 2005-2006 Fabrice Bellard

 * 

 * 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 "vl.h"

/* debug ESP card */

//#define DEBUG_ESP

#ifdef DEBUG_ESP

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

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

#define pic_set_irq(irq, level) \

do { printf("ESP: set_irq(%d): %d\n", (irq), (level)); pic_set_irq((irq),(level));} while (0)

#else

#define DPRINTF(fmt, args...)

#endif

#define ESPDMA_REGS 4

#define ESPDMA_MAXADDR (ESPDMA_REGS * 4 - 1)

#define ESP_MAXREG 0x3f

#define TI_BUFSZ 32

#define DMA_VER 0xa0000000

#define DMA_INTR 1

#define DMA_INTREN 0x10

#define DMA_WRITE_MEM 0x100

#define DMA_LOADED 0x04000000

typedef struct ESPState ESPState;

struct ESPState {

    BlockDriverState **bd;

    uint8_t rregs[ESP_MAXREG];

    uint8_t wregs[ESP_MAXREG];

    int irq;

    uint32_t espdmaregs[ESPDMA_REGS];

    uint32_t ti_size;

    uint32_t ti_rptr, ti_wptr;

    uint8_t ti_buf[TI_BUFSZ];

    int dma;

    SCSIDevice *scsi_dev[MAX_DISKS];

    SCSIDevice *current_dev;

};

#define STAT_DO 0x00

#define STAT_DI 0x01

#define STAT_CD 0x02

#define STAT_ST 0x03

#define STAT_MI 0x06

#define STAT_MO 0x07

#define STAT_TC 0x10

#define STAT_IN 0x80

#define INTR_FC 0x08

#define INTR_BS 0x10

#define INTR_DC 0x20

#define INTR_RST 0x80

#define SEQ_0 0x0

#define SEQ_CD 0x4

static void handle_satn(ESPState *s)

{

    uint8_t buf[32];

    uint32_t dmaptr, dmalen;

    int target;

    int32_t datalen;

    dmalen = s->wregs[0] | (s->wregs[1] << 8);

    target = s->wregs[4] & 7;

    DPRINTF("Select with ATN len %d target %d\n", dmalen, target);

    if (s->dma) {

        dmaptr = iommu_translate(s->espdmaregs[1]);

        DPRINTF("DMA Direction: %c, addr 0x%8.8x\n",

                s->espdmaregs[0] & DMA_WRITE_MEM ? 'w': 'r', dmaptr);

        cpu_physical_memory_read(dmaptr, buf, dmalen);

    } else {

        buf[0] = 0;

        memcpy(&buf[1], s->ti_buf, dmalen);

        dmalen++;

    }

    s->ti_size = 0;

    s->ti_rptr = 0;

    s->ti_wptr = 0;

    if (target >= 4 || !s->scsi_dev[target]) {

        // No such drive

        s->rregs[4] = STAT_IN;

        s->rregs[5] = INTR_DC;

        s->rregs[6] = SEQ_0;

        s->espdmaregs[0] |= DMA_INTR;

        pic_set_irq(s->irq, 1);

        return;

    }

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

    datalen = scsi_send_command(s->current_dev, 0, &buf[1]);

    if (datalen == 0) {

        s->ti_size = 0;

    } else {

        s->rregs[4] = STAT_IN | STAT_TC;

        if (datalen > 0) {

            s->rregs[4] |= STAT_DI;

            s->ti_size = datalen;

        } else {

            s->rregs[4] |= STAT_DO;

            s->ti_size = -datalen;

        }

    }

    s->rregs[5] = INTR_BS | INTR_FC;

    s->rregs[6] = SEQ_CD;

    s->espdmaregs[0] |= DMA_INTR;

    pic_set_irq(s->irq, 1);

}

static void dma_write(ESPState *s, const uint8_t *buf, uint32_t len)

{

    uint32_t dmaptr;

    DPRINTF("Transfer status len %d\n", len);

    if (s->dma) {

        dmaptr = iommu_translate(s->espdmaregs[1]);

        DPRINTF("DMA Direction: %c\n",

                s->espdmaregs[0] & DMA_WRITE_MEM ? 'w': 'r');

        cpu_physical_memory_write(dmaptr, buf, len);

        s->rregs[4] = STAT_IN | STAT_TC | STAT_ST;

        s->rregs[5] = INTR_BS | INTR_FC;

        s->rregs[6] = SEQ_CD;

    } else {

        memcpy(s->ti_buf, buf, len);

        s->ti_size = len;

        s->ti_rptr = 0;

        s->ti_wptr = 0;

        s->rregs[7] = len;

    }

    s->espdmaregs[0] |= DMA_INTR;

    pic_set_irq(s->irq, 1);

}

static const uint8_t okbuf[] = {0, 0};

static void esp_command_complete(void *opaque, uint32_t tag, int fail)

{

    ESPState *s = (ESPState *)opaque;

    DPRINTF("SCSI Command complete\n");

    if (s->ti_size != 0)

        DPRINTF("SCSI command completed unexpectedly\n");

    s->ti_size = 0;

    /* ??? Report failures.  */

    if (fail)

        DPRINTF("Command failed\n");

    s->rregs[4] = STAT_IN | STAT_TC | STAT_ST;

}

static void handle_ti(ESPState *s)

{

    uint32_t dmaptr, dmalen, minlen, len, from, to;

    unsigned int i;

    int to_device;

    uint8_t buf[TARGET_PAGE_SIZE];

    dmalen = s->wregs[0] | (s->wregs[1] << 8);

    if (dmalen==0) {

      dmalen=0x10000;

    }

    minlen = (dmalen < s->ti_size) ? dmalen : s->ti_size;

    DPRINTF("Transfer Information len %d\n", minlen);

    if (s->dma) {

        dmaptr = iommu_translate(s->espdmaregs[1]);

        /* Check if the transfer writes to to reads from the device.  */

        to_device = (s->espdmaregs[0] & DMA_WRITE_MEM) == 0;

        DPRINTF("DMA Direction: %c, addr 0x%8.8x %08x\n",

                to_device ? 'r': 'w', dmaptr, s->ti_size);

        from = s->espdmaregs[1];

        to = from + minlen;

        for (i = 0; i < minlen; i += len, from += len) {

            dmaptr = iommu_translate(s->espdmaregs[1] + i);

            if ((from & TARGET_PAGE_MASK) != (to & TARGET_PAGE_MASK)) {

               len = TARGET_PAGE_SIZE - (from & ~TARGET_PAGE_MASK);

            } else {

               len = to - from;

            }

            DPRINTF("DMA address p %08x v %08x len %08x, from %08x, to %08x\n", dmaptr, s->espdmaregs[1] + i, len, from, to);

            s->ti_size -= len;

            if (to_device) {

                cpu_physical_memory_read(dmaptr, buf, len);

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

            } else {

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

                cpu_physical_memory_write(dmaptr, buf, len);

            }

        }

        if (s->ti_size) {

            s->rregs[4] = STAT_IN | STAT_TC | (to_device ? STAT_DO : STAT_DI);

        }

        s->rregs[5] = INTR_BS;

        s->rregs[6] = 0;

        s->rregs[7] = 0;

        s->espdmaregs[0] |= DMA_INTR;

    }        

    pic_set_irq(s->irq, 1);

}

static void esp_reset(void *opaque)

{

    ESPState *s = opaque;

    memset(s->rregs, 0, ESP_MAXREG);

    memset(s->wregs, 0, ESP_MAXREG);

    s->rregs[0x0e] = 0x4; // Indicate fas100a

    memset(s->espdmaregs, 0, ESPDMA_REGS * 4);

    s->ti_size = 0;

    s->ti_rptr = 0;

    s->ti_wptr = 0;

    s->dma = 0;

}

static uint32_t esp_mem_readb(void *opaque, target_phys_addr_t addr)

{

    ESPState *s = opaque;

    uint32_t saddr;

    saddr = (addr & ESP_MAXREG) >> 2;

    DPRINTF("read reg[%d]: 0x%2.2x\n", saddr, s->rregs[saddr]);

    switch (saddr) {

    case 2:

        // FIFO

        if (s->ti_size > 0) {

            s->ti_size--;

            if ((s->rregs[4] & 6) == 0) {

                /* Data in/out.  */

                scsi_read_data(s->current_dev, &s->rregs[2], 0);

            } else {

                s->rregs[2] = s->ti_buf[s->ti_rptr++];

            }

            pic_set_irq(s->irq, 1);

        }

        if (s->ti_size == 0) {

            s->ti_rptr = 0;

            s->ti_wptr = 0;

        }

        break;

    case 5:

        // interrupt

        // Clear status bits except TC

        s->rregs[4] &= STAT_TC;

        pic_set_irq(s->irq, 0);

        s->espdmaregs[0] &= ~DMA_INTR;

        break;

    default:

        break;

    }

    return s->rregs[saddr];

}

static void esp_mem_writeb(void *opaque, target_phys_addr_t addr, uint32_t val)

{

    ESPState *s = opaque;

    uint32_t saddr;

    saddr = (addr & ESP_MAXREG) >> 2;

    DPRINTF("write reg[%d]: 0x%2.2x -> 0x%2.2x\n", saddr, s->wregs[saddr], val);

    switch (saddr) {

    case 0:

    case 1:

        s->rregs[saddr] = val;

        break;

    case 2:

        // FIFO

        if ((s->rregs[4] & 6) == 0) {

            uint8_t buf;

            buf = val & 0xff;

            s->ti_size--;

            scsi_write_data(s->current_dev, &buf, 0);

        } else {

            s->ti_size++;

            s->ti_buf[s->ti_wptr++] = val & 0xff;

        }

        break;

    case 3:

        s->rregs[saddr] = val;

        // Command

        if (val & 0x80) {

            s->dma = 1;

        } else {

            s->dma = 0;

        }

        switch(val & 0x7f) {

        case 0:

            DPRINTF("NOP (%2.2x)\n", val);

            break;

        case 1:

            DPRINTF("Flush FIFO (%2.2x)\n", val);

            //s->ti_size = 0;

            s->rregs[5] = INTR_FC;

            s->rregs[6] = 0;

            break;

        case 2:

            DPRINTF("Chip reset (%2.2x)\n", val);

            esp_reset(s);

            break;

        case 3:

            DPRINTF("Bus reset (%2.2x)\n", val);

            s->rregs[5] = INTR_RST;

            if (!(s->wregs[8] & 0x40)) {

                s->espdmaregs[0] |= DMA_INTR;

                pic_set_irq(s->irq, 1);

            }

            break;

        case 0x10:

            handle_ti(s);

            break;

        case 0x11:

            DPRINTF("Initiator Command Complete Sequence (%2.2x)\n", val);

            dma_write(s, okbuf, 2);

            break;

        case 0x12:

            DPRINTF("Message Accepted (%2.2x)\n", val);

            dma_write(s, okbuf, 2);

            s->rregs[5] = INTR_DC;

            s->rregs[6] = 0;

            break;

        case 0x1a:

            DPRINTF("Set ATN (%2.2x)\n", val);

            break;

        case 0x42:

            handle_satn(s);

            break;

        case 0x43:

            DPRINTF("Set ATN & stop (%2.2x)\n", val);

            handle_satn(s);

            break;

        default:

            DPRINTF("Unhandled ESP command (%2.2x)\n", val);

            break;

        }

        break;

    case 4 ... 7:

        break;

    case 8:

        s->rregs[saddr] = val;

        break;

    case 9 ... 10:

        break;

    case 11:

        s->rregs[saddr] = val & 0x15;

        break;

    case 12 ... 15:

        s->rregs[saddr] = val;

        break;

    default:

        break;

    }

    s->wregs[saddr] = val;

}

static CPUReadMemoryFunc *esp_mem_read[3] = {

    esp_mem_readb,

    esp_mem_readb,

    esp_mem_readb,

};

static CPUWriteMemoryFunc *esp_mem_write[3] = {

    esp_mem_writeb,

    esp_mem_writeb,

    esp_mem_writeb,

};

static uint32_t espdma_mem_readl(void *opaque, target_phys_addr_t addr)

{

    ESPState *s = opaque;

    uint32_t saddr;

    saddr = (addr & ESPDMA_MAXADDR) >> 2;

    DPRINTF("read dmareg[%d]: 0x%8.8x\n", saddr, s->espdmaregs[saddr]);

    return s->espdmaregs[saddr];

}

static void espdma_mem_writel(void *opaque, target_phys_addr_t addr, uint32_t val)

{

    ESPState *s = opaque;

    uint32_t saddr;

    saddr = (addr & ESPDMA_MAXADDR) >> 2;

    DPRINTF("write dmareg[%d]: 0x%8.8x -> 0x%8.8x\n", saddr, s->espdmaregs[saddr], val);

    switch (saddr) {

    case 0:

        if (!(val & DMA_INTREN))

            pic_set_irq(s->irq, 0);

        if (val & 0x80) {

            esp_reset(s);

        } else if (val & 0x40) {

            val &= ~0x40;

        } else if (val == 0)

            val = 0x40;

        val &= 0x0fffffff;

        val |= DMA_VER;

        break;

    case 1:

        s->espdmaregs[0] |= DMA_LOADED;

        break;

    default:

        break;

    }

    s->espdmaregs[saddr] = val;

}

static CPUReadMemoryFunc *espdma_mem_read[3] = {

    espdma_mem_readl,

    espdma_mem_readl,

    espdma_mem_readl,

};

static CPUWriteMemoryFunc *espdma_mem_write[3] = {

    espdma_mem_writel,

    espdma_mem_writel,

    espdma_mem_writel,

};

static void esp_save(QEMUFile *f, void *opaque)

{

    ESPState *s = opaque;

    unsigned int i;

    qemu_put_buffer(f, s->rregs, ESP_MAXREG);

    qemu_put_buffer(f, s->wregs, ESP_MAXREG);

    qemu_put_be32s(f, &s->irq);

    for (i = 0; i < ESPDMA_REGS; i++)

        qemu_put_be32s(f, &s->espdmaregs[i]);

    qemu_put_be32s(f, &s->ti_size);

    qemu_put_be32s(f, &s->ti_rptr);

    qemu_put_be32s(f, &s->ti_wptr);

    qemu_put_buffer(f, s->ti_buf, TI_BUFSZ);

    qemu_put_be32s(f, &s->dma);

}

static int esp_load(QEMUFile *f, void *opaque, int version_id)

{

    ESPState *s = opaque;

    unsigned int i;

    if (version_id != 1)

        return -EINVAL;

    qemu_get_buffer(f, s->rregs, ESP_MAXREG);

    qemu_get_buffer(f, s->wregs, ESP_MAXREG);

    qemu_get_be32s(f, &s->irq);

    for (i = 0; i < ESPDMA_REGS; i++)

        qemu_get_be32s(f, &s->espdmaregs[i]);

    qemu_get_be32s(f, &s->ti_size);

    qemu_get_be32s(f, &s->ti_rptr);

    qemu_get_be32s(f, &s->ti_wptr);

    qemu_get_buffer(f, s->ti_buf, TI_BUFSZ);

    qemu_get_be32s(f, &s->dma);

    return 0;

}

void esp_init(BlockDriverState **bd, int irq, uint32_t espaddr, uint32_t espdaddr)

{

    ESPState *s;

    int esp_io_memory, espdma_io_memory;

    int i;

    s = qemu_mallocz(sizeof(ESPState));

    if (!s)

        return;

    s->bd = bd;

    s->irq = irq;

    esp_io_memory = cpu_register_io_memory(0, esp_mem_read, esp_mem_write, s);

    cpu_register_physical_memory(espaddr, ESP_MAXREG*4, esp_io_memory);

    espdma_io_memory = cpu_register_io_memory(0, espdma_mem_read, espdma_mem_write, s);

    cpu_register_physical_memory(espdaddr, 16, espdma_io_memory);

    esp_reset(s);

    register_savevm("esp", espaddr, 1, esp_save, esp_load, s);

    qemu_register_reset(esp_reset, s);

    for (i = 0; i < MAX_DISKS; i++) {

        if (bs_table[i]) {

            s->scsi_dev[i] =

                scsi_disk_init(bs_table[i], esp_command_complete, s);

        }

    }

}