esp.c

qemu虚拟机代码

            switch(format) {
            case 0:
                len = cdrom_read_toc(nb_sectors, buf, msf, start_track);
                if (len < 0)
                    goto error_cmd;
                s->ti_size = len;
                break;
            case 1:
                /* multi session : only a single session defined */
                memset(buf, 0, 12);
                buf[1] = 0x0a;
                buf[2] = 0x01;
                buf[3] = 0x01;
                s->ti_size = 12;
                break;
            case 2:
                len = cdrom_read_toc_raw(nb_sectors, buf, msf, start_track);
                if (len < 0)
                    goto error_cmd;
                s->ti_size = len;
                break;
            default:
            error_cmd:
                DPRINTF("Read TOC error\n");
                // XXX error handling
                break;
            }
	    s->ti_dir = 1;
            break;
        }
    default:
	DPRINTF("Unknown SCSI command (%2.2x)\n", buf[1]);
	break;
    }
    s->rregs[4] = STAT_IN | STAT_TC | STAT_DI;
    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, dmalen;

    dmalen = s->wregs[0] | (s->wregs[1] << 8);
    DPRINTF("Transfer status len %d\n", dmalen);
    if (s->dma) {
	dmaptr = iommu_translate(s->espdmaregs[1]);
	DPRINTF("DMA Direction: %c\n", s->espdmaregs[0] & 0x100? '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 = dmalen;
	s->ti_rptr = 0;
	s->ti_wptr = 0;
	s->rregs[7] = dmalen;
    }
    s->espdmaregs[0] |= DMA_INTR;
    pic_set_irq(s->irq, 1);

}

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

static void handle_ti(ESPState *s)
{
    uint32_t dmaptr, dmalen;
    unsigned int i;

    dmalen = s->wregs[0] | (s->wregs[1] << 8);
    DPRINTF("Transfer Information len %d\n", dmalen);
    if (s->dma) {
	dmaptr = iommu_translate(s->espdmaregs[1]);
	DPRINTF("DMA Direction: %c, addr 0x%8.8x\n", s->espdmaregs[0] & 0x100? 'w': 'r', dmaptr);
	for (i = 0; i < s->ti_size; i++) {
	    dmaptr = iommu_translate(s->espdmaregs[1] + i);
	    if (s->ti_dir)
		cpu_physical_memory_write(dmaptr, &s->ti_buf[i], 1);
	    else
		cpu_physical_memory_read(dmaptr, &s->ti_buf[i], 1);
	}
        if (s->dma_cb) {
            s->dma_cb(s, s->espdmaregs[1], dmalen);
            s->dma_cb = NULL;
        }
	s->rregs[4] = STAT_IN | STAT_TC | STAT_ST;
	s->rregs[5] = INTR_BS;
	s->rregs[6] = 0;
	s->espdmaregs[0] |= DMA_INTR;
    } else {
	s->ti_size = dmalen;
	s->ti_rptr = 0;
	s->ti_wptr = 0;
	s->rregs[7] = dmalen;
    }	
    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->ti_dir = 0;
    s->dma = 0;
    s->dma_cb = NULL;
}

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--;
	    s->rregs[saddr] = 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
	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_be32s(f, &s->ti_dir);
    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_be32s(f, &s->ti_dir);
    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;

    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);
}