ide.c

qemu虚拟机代码

static inline void cpu_to_ube16(uint8_t *buf, int val)
{
    buf[0] = val >> 8;
    buf[1] = val;
}

static inline void cpu_to_ube32(uint8_t *buf, unsigned int val)
{
    buf[0] = val >> 24;
    buf[1] = val >> 16;
    buf[2] = val >> 8;
    buf[3] = val;
}

static inline int ube16_to_cpu(const uint8_t *buf)
{
    return (buf[0] << 8) | buf[1];
}

static inline int ube32_to_cpu(const uint8_t *buf)
{
    return (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
}

static void lba_to_msf(uint8_t *buf, int lba)
{
    lba += 150;
    buf[0] = (lba / 75) / 60;
    buf[1] = (lba / 75) % 60;
    buf[2] = lba % 75;
}

static void cd_read_sector(BlockDriverState *bs, int lba, uint8_t *buf, 
                           int sector_size)
{
    switch(sector_size) {
    case 2048:
        bdrv_read(bs, (int64_t)lba << 2, buf, 4);
        break;
    case 2352:
        /* sync bytes */
        buf[0] = 0x00;
        memset(buf + 1, 0xff, 10);
        buf[11] = 0x00;
        buf += 12;
        /* MSF */
        lba_to_msf(buf, lba);
        buf[3] = 0x01; /* mode 1 data */
        buf += 4;
        /* data */
        bdrv_read(bs, (int64_t)lba << 2, buf, 4);
        buf += 2048;
        /* ECC */
        memset(buf, 0, 288);
        break;
    default:
        break;
    }
}

/* The whole ATAPI transfer logic is handled in this function */
static void ide_atapi_cmd_reply_end(IDEState *s)
{
    int byte_count_limit, size;
#ifdef DEBUG_IDE_ATAPI
    printf("reply: tx_size=%d elem_tx_size=%d index=%d\n", 
           s->packet_transfer_size,
           s->elementary_transfer_size,
           s->io_buffer_index);
#endif
    if (s->packet_transfer_size <= 0) {
        /* end of transfer */
        ide_transfer_stop(s);
        s->status = READY_STAT;
        s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
        ide_set_irq(s);
#ifdef DEBUG_IDE_ATAPI
        printf("status=0x%x\n", s->status);
#endif
    } else {
        /* see if a new sector must be read */
        if (s->lba != -1 && s->io_buffer_index >= s->cd_sector_size) {
            cd_read_sector(s->bs, s->lba, s->io_buffer, s->cd_sector_size);
            s->lba++;
            s->io_buffer_index = 0;
        }
        if (s->elementary_transfer_size > 0) {
            /* there are some data left to transmit in this elementary
               transfer */
            size = s->cd_sector_size - s->io_buffer_index;
            if (size > s->elementary_transfer_size)
                size = s->elementary_transfer_size;
            ide_transfer_start(s, s->io_buffer + s->io_buffer_index, 
                               size, ide_atapi_cmd_reply_end);
            s->packet_transfer_size -= size;
            s->elementary_transfer_size -= size;
            s->io_buffer_index += size;
        } else {
            /* a new transfer is needed */
            s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO;
            byte_count_limit = s->lcyl | (s->hcyl << 8);
#ifdef DEBUG_IDE_ATAPI
            printf("byte_count_limit=%d\n", byte_count_limit);
#endif
            if (byte_count_limit == 0xffff)
                byte_count_limit--;
            size = s->packet_transfer_size;
            if (size > byte_count_limit) {
                /* byte count limit must be even if this case */
                if (byte_count_limit & 1)
                    byte_count_limit--;
                size = byte_count_limit;
            }
            s->lcyl = size;
            s->hcyl = size >> 8;
            s->elementary_transfer_size = size;
            /* we cannot transmit more than one sector at a time */
            if (s->lba != -1) {
                if (size > (s->cd_sector_size - s->io_buffer_index))
                    size = (s->cd_sector_size - s->io_buffer_index);
            }
            ide_transfer_start(s, s->io_buffer + s->io_buffer_index, 
                               size, ide_atapi_cmd_reply_end);
            s->packet_transfer_size -= size;
            s->elementary_transfer_size -= size;
            s->io_buffer_index += size;
            ide_set_irq(s);
#ifdef DEBUG_IDE_ATAPI
            printf("status=0x%x\n", s->status);
#endif
        }
    }
}

/* send a reply of 'size' bytes in s->io_buffer to an ATAPI command */
static void ide_atapi_cmd_reply(IDEState *s, int size, int max_size)
{
    if (size > max_size)
        size = max_size;
    s->lba = -1; /* no sector read */
    s->packet_transfer_size = size;
    s->elementary_transfer_size = 0;
    s->io_buffer_index = 0;

    s->status = READY_STAT;
    ide_atapi_cmd_reply_end(s);
}

/* start a CD-CDROM read command */
static void ide_atapi_cmd_read_pio(IDEState *s, int lba, int nb_sectors,
                                   int sector_size)
{
    s->lba = lba;
    s->packet_transfer_size = nb_sectors * sector_size;
    s->elementary_transfer_size = 0;
    s->io_buffer_index = sector_size;
    s->cd_sector_size = sector_size;

    s->status = READY_STAT;
    ide_atapi_cmd_reply_end(s);
}

/* ATAPI DMA support */
static int ide_atapi_cmd_read_dma_cb(IDEState *s, 
                                     target_phys_addr_t phys_addr, 
                                     int transfer_size1)
{
    int len, transfer_size;
    
    transfer_size = transfer_size1;
    while (transfer_size > 0) {
#ifdef DEBUG_IDE_ATAPI
        printf("transfer_size: %d phys_addr=%08x\n", transfer_size, phys_addr);
#endif
        if (s->packet_transfer_size <= 0)
            break;
        len = s->cd_sector_size - s->io_buffer_index;
        if (len <= 0) {
            /* transfert next data */
            cd_read_sector(s->bs, s->lba, s->io_buffer, s->cd_sector_size);
            s->lba++;
            s->io_buffer_index = 0;
            len = s->cd_sector_size;
        }
        if (len > transfer_size)
            len = transfer_size;
        cpu_physical_memory_write(phys_addr, 
                                  s->io_buffer + s->io_buffer_index, len);
        s->packet_transfer_size -= len;
        s->io_buffer_index += len;
        transfer_size -= len;
        phys_addr += len;
    }
    if (s->packet_transfer_size <= 0) {
        s->status = READY_STAT;
        s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
        ide_set_irq(s);
#ifdef DEBUG_IDE_ATAPI
        printf("dma status=0x%x\n", s->status);
#endif
        return 0;
    }
    return transfer_size1 - transfer_size;
}

/* start a CD-CDROM read command with DMA */
/* XXX: test if DMA is available */
static void ide_atapi_cmd_read_dma(IDEState *s, int lba, int nb_sectors,
                                   int sector_size)
{
    s->lba = lba;
    s->packet_transfer_size = nb_sectors * sector_size;
    s->io_buffer_index = sector_size;
    s->cd_sector_size = sector_size;

    s->status = READY_STAT | DRQ_STAT;
    ide_dma_start(s, ide_atapi_cmd_read_dma_cb);
}

static void ide_atapi_cmd_read(IDEState *s, int lba, int nb_sectors, 
                               int sector_size)
{
#ifdef DEBUG_IDE_ATAPI
    printf("read: LBA=%d nb_sectors=%d\n", lba, nb_sectors);
#endif
    if (s->atapi_dma) {
        ide_atapi_cmd_read_dma(s, lba, nb_sectors, sector_size);
    } else {
        ide_atapi_cmd_read_pio(s, lba, nb_sectors, sector_size);
    }
}

/* same toc as bochs. Return -1 if error or the toc length */
/* XXX: check this */
static int cdrom_read_toc(IDEState *s, uint8_t *buf, int msf, int start_track)
{
    uint8_t *q;
    int nb_sectors, len;
    
    if (start_track > 1 && start_track != 0xaa)
        return -1;
    q = buf + 2;
    *q++ = 1; /* first session */
    *q++ = 1; /* last session */
    if (start_track <= 1) {
        *q++ = 0; /* reserved */
        *q++ = 0x14; /* ADR, control */
        *q++ = 1;    /* track number */
        *q++ = 0; /* reserved */
        if (msf) {
            *q++ = 0; /* reserved */
            lba_to_msf(q, 0);
            q += 3;
        } else {
            /* sector 0 */
            cpu_to_ube32(q, 0);
            q += 4;
        }
    }
    /* lead out track */
    *q++ = 0; /* reserved */
    *q++ = 0x16; /* ADR, control */
    *q++ = 0xaa; /* track number */
    *q++ = 0; /* reserved */
    nb_sectors = s->nb_sectors >> 2;
    if (msf) {
        *q++ = 0; /* reserved */
        lba_to_msf(q, nb_sectors);
        q += 3;
    } else {
        cpu_to_ube32(q, nb_sectors);
        q += 4;
    }
    len = q - buf;
    cpu_to_ube16(buf, len - 2);
    return len;
}

/* mostly same info as PearPc */
static int cdrom_read_toc_raw(IDEState *s, uint8_t *buf, int msf, 
                              int session_num)
{
    uint8_t *q;
    int nb_sectors, len;
    
    q = buf + 2;
    *q++ = 1; /* first session */
    *q++ = 1; /* last session */

    *q++ = 1; /* session number */
    *q++ = 0x14; /* data track */
    *q++ = 0; /* track number */
    *q++ = 0xa0; /* lead-in */
    *q++ = 0; /* min */
    *q++ = 0; /* sec */
    *q++ = 0; /* frame */
    *q++ = 0;
    *q++ = 1; /* first track */
    *q++ = 0x00; /* disk type */
    *q++ = 0x00;
    
    *q++ = 1; /* session number */
    *q++ = 0x14; /* data track */
    *q++ = 0; /* track number */
    *q++ = 0xa1;
    *q++ = 0; /* min */
    *q++ = 0; /* sec */
    *q++ = 0; /* frame */
    *q++ = 0;
    *q++ = 1; /* last track */
    *q++ = 0x00;
    *q++ = 0x00;
    
    *q++ = 1; /* session number */
    *q++ = 0x14; /* data track */
    *q++ = 0; /* track number */
    *q++ = 0xa2; /* lead-out */
    *q++ = 0; /* min */
    *q++ = 0; /* sec */
    *q++ = 0; /* frame */
    nb_sectors = s->nb_sectors >> 2;
    if (msf) {
        *q++ = 0; /* reserved */
        lba_to_msf(q, nb_sectors);
        q += 3;
    } else {
        cpu_to_ube32(q, nb_sectors);
        q += 4;
    }

    *q++ = 1; /* session number */
    *q++ = 0x14; /* ADR, control */
    *q++ = 0;    /* track number */
    *q++ = 1;    /* point */
    *q++ = 0; /* min */
    *q++ = 0; /* sec */
    *q++ = 0; /* frame */
    if (msf) {
        *q++ = 0; 
        lba_to_msf(q, 0);
        q += 3;
    } else {
        *q++ = 0; 
        *q++ = 0; 
        *q++ = 0; 
        *q++ = 0; 
    }

    len = q - buf;
    cpu_to_ube16(buf, len - 2);
    return len;
}

static void ide_atapi_cmd(IDEState *s)
{
    const uint8_t *packet;
    uint8_t *buf;
    int max_len;

    packet = s->io_buffer;
    buf = s->io_buffer;
#ifdef DEBUG_IDE_ATAPI
    {
        int i;
        printf("ATAPI limit=0x%x packet:", s->lcyl | (s->hcyl << 8));
        for(i = 0; i < ATAPI_PACKET_SIZE; i++) {
            printf(" %02x", packet[i]);
        }
        printf("\n");
    }
#endif
    switch(s->io_buffer[0]) {
    case GPCMD_TEST_UNIT_READY:
        if (bdrv_is_inserted(s->bs)) {
            ide_atapi_cmd_ok(s);
        } else {
            ide_atapi_cmd_error(s, SENSE_NOT_READY, 
                                ASC_MEDIUM_NOT_PRESENT);
        }
        break;
    case GPCMD_MODE_SENSE_10:
        {
            int action, code;
            max_len = ube16_to_cpu(packet + 7);
            action = packet[2] >> 6;
            code = packet[2] & 0x3f;
            switch(action) {
            case 0: /* current values */
                switch(code) {
                case 0x01: /* error recovery */
                    cpu_to_ube16(&buf[0], 16 + 6);
                    buf[2] = 0x70;
                    buf[3] = 0;
                    buf[4] = 0;
                    buf[5] = 0;
                    buf[6] = 0;
                    buf[7] = 0;

                    buf[8] = 0x01;
                    buf[9] = 0x06;
                    buf[10] = 0x00;
                    buf[11] = 0x05;
                    buf[12] = 0x00;
                    buf[13] = 0x00;
                    buf[14] = 0x00;
                    buf[15] = 0x00;
                    ide_atapi_cmd_reply(s, 16, max_len);
                    break;
                case 0x2a:
                    cpu_to_ube16(&buf[0], 28 + 6);
                    buf[2] = 0x70;
                    buf[3] = 0;
                    buf[4] = 0;
                    buf[5] = 0;
                    buf[6] = 0;
                    buf[7] = 0;

                    buf[8] = 0x2a;
                    buf[9] = 0x12;
                    buf[10] = 0x00;
                    buf[11] = 0x00;
                    
                    buf[12] = 0x70;
                    buf[13] = 3 << 5;
                    buf[14] = (1 << 0) | (1 << 3) | (1 << 5);
                    if (bdrv_is_locked(s->bs))